```

[Federal Register Volume 76, Number 179 (Thursday, September 15, 2011)]
[Rules and Regulations]
[Pages 57106-57513]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-20740]

[[Page 57105]]

Vol. 76

Thursday,

No. 179

September 15, 2011

Part II

Environmental Protection Agency

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40 CFR Parts 85, 86, 600, et al.

Department of Transportation

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National Highway Traffic Safety Administration

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49 CFR Parts 523, 534, and 535

Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for 
Medium- and Heavy-Duty Engines and Vehicles; Final Rule

Federal Register / Vol. 76, No. 179 / Thursday, September 15, 2011 / 
Rules and Regulations

[[Page 57106]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 85, 86, 600, 1033, 1036, 1037, 1039, 1065, 1066, and 
1068

DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Parts 523, 534, and 535

[EPA-HQ-OAR-2010-0162; NHTSA-2010-0079; FRL-9455-1]
RIN 2060-AP61; 2127-AK74

Greenhouse Gas Emissions Standards and Fuel Efficiency Standards 
for Medium- and Heavy-Duty Engines and Vehicles

AGENCY: Environmental Protection Agency (EPA) and National Highway 
Traffic Safety Administration (NHTSA), DOT.

ACTION: Final Rules.

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SUMMARY: EPA and NHTSA, on behalf of the Department of Transportation, 
are each finalizing rules to establish a comprehensive Heavy-Duty 
National Program that will reduce greenhouse gas emissions and fuel 
consumption for on-road heavy-duty vehicles, responding to the 
President's directive on May 21, 2010, to take coordinated steps to 
produce a new generation of clean vehicles. NHTSA's final fuel 
consumption standards and EPA's final carbon dioxide (CO2) 
emissions standards are tailored to each of three regulatory categories 
of heavy-duty vehicles: Combination Tractors; Heavy-duty Pickup Trucks 
and Vans; and Vocational Vehicles. The rules include separate standards 
for the engines that power combination tractors and vocational 
vehicles. Certain rules are exclusive to the EPA program. These include 
EPA's final hydrofluorocarbon standards to control leakage from air 
conditioning systems in combination tractors, and pickup trucks and 
vans. These also include EPA's final nitrous oxide (N2O) and 
methane (CH4) emissions standards that apply to all heavy-
duty engines, pickup trucks and vans.
    EPA's final greenhouse gas emission standards under the Clean Air 
Act will begin with model year 2014. NHTSA's final fuel consumption 
standards under the Energy Independence and Security Act of 2007 will 
be voluntary in model years 2014 and 2015, becoming mandatory with 
model year 2016 for most regulatory categories. Commercial trailers are 
not regulated in this phase of the Heavy-Duty National Program.
    The agencies estimate that the combined standards will reduce 
CO2 emissions by approximately 270 million metric tons and 
save 530 million barrels of oil over the life of vehicles sold during 
the 2014 through 2018 model years, providing over $7 billion in net 
societal benefits, and $49 billion in net societal benefits when 
private fuel savings are considered.
    EPA is also finalizing provisions allowing light-duty vehicle 
manufacturers to use CO2 credits to meet the light-duty 
vehicle N2O and CH4 standards, technical 
amendments to the fuel economy provisions for light-duty vehicles, and 
a technical amendment to the criteria pollutant emissions requirements 
for certain switch locomotives.

DATES: These final rules are effective on November 14, 2011. The 
incorporation by reference of certain publications listed in this 
regulation is approved by the Director of the Federal Register as of 
November 14, 2011.

ADDRESSES: EPA and NHTSA have established dockets for this action under 
Docket ID No. EPA-HQ-OAR-2010-0162 and NHTSA-2010-0079, respectively. 
All documents in the docket are listed on the http://www.regulations.gov Web site. Although listed in the index, some 
information is not publicly available, e.g., confidential business 
information or other information whose disclosure is restricted by 
statute. Certain other material, such as copyrighted material, is not 
placed on the Internet and will be publicly available only in hard copy 
form. Publicly available docket materials are available either 
electronically through http://www.regulations.gov or in hard copy at 
the following locations: EPA: EPA Docket Center, EPA/DC, EPA West 
Building, 1301 Constitution Ave., NW., Room 3334, Washington, DC. The 
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the Public 
Reading Room is (202) 566-1744, and the telephone number for the Air 
Docket is (202) 566-1742. NHTSA: Docket Management Facility, M-30, U.S. 
Department of Transportation, West Building, Ground Floor, Rm. W12-140, 
1200 New Jersey Avenue, SE., Washington, DC 20590. The Docket 
Management Facility is open between 9 a.m. and 5 p.m. Eastern Time, 
Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: NHTSA: Lily Smith, Office of Chief 
Counsel, National Highway Traffic Safety Administration, 1200 New 
Jersey Avenue, SE., Washington, DC 20590. Telephone: (202) 366-2992. 
EPA: Lauren Steele, Office of Transportation and Air Quality, 
Assessment and Standards Division (ASD), Environmental Protection 
Agency, 2000 Traverwood Drive, Ann Arbor, MI 48105; telephone number: 
(734) 214-4788; fax number: (734) 214-4816; e-mail address: 
steele.lauren@epa.gov, or contact the Office of Transportation and Air 
Quality at OTAQPUBLICWEB@epa.gov.

SUPPLEMENTARY INFORMATION: 

A. Does this action apply to me?

    This action affects companies that manufacture, sell, or import 
into the United States new heavy-duty engines and new Class 2b through 
8 trucks, including combination tractors, school and transit buses, 
vocational vehicles such as utility service trucks, as well as \3/4\-
ton and 1-ton pickup trucks and vans. The heavy-duty category 
incorporates all motor vehicles with a gross vehicle weight rating of 
8,500 pounds or greater, and the engines that power them, except for 
medium-duty passenger vehicles already covered by the greenhouse gas 
emissions standards and corporate average fuel economy standards issued 
for light-duty model year 2012-2016 vehicles. Regulated categories and 
entities include the following:

------------------------------------------------------------------------
                                                        Examples of
           Category              NAICS Code \a\    potentially affected
                                                         entities
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Industry......................            336111  Motor Vehicle
                                          336112   Manufacturers, Engine
                                                   and Truck
                                                   Manufacturers.
                                          336120
Industry......................            541514  Commercial Importers
                                          811112   of Vehicles and
                                                   Vehicle Components.
                                          811198
Industry......................            336111  Alternative Fuel
                                                   Vehicle Converters.
                                          336112

[[Page 57107]]

 
                                          422720
                                          454312
                                          541514
                                          541690
                                          811198
Industry......................            333618  Manufacturers,
                                          336510   remanufacturers and
                                                   importers of
                                                   locomotives and
                                                   locomotive engines.
------------------------------------------------------------------------
Note:
\a\ North American Industry Classification System (NAICS).

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely covered by these rules. 
This table lists the types of entities that the agencies are aware may 
be regulated by this action. Other types of entities not listed in the 
table could also be regulated. To determine whether your activities are 
regulated by this action, you should carefully examine the 
applicability criteria in the referenced regulations. You may direct 
questions regarding the applicability of this action to the persons 
listed in the preceding FOR FURTHER INFORMATION CONTACT section.

Table of Contents

A. Does this action apply to me?
I. Overview
    A. Introduction
    B. Building Blocks of the Heavy-Duty National Program
    C. Summary of the Final EPA and NHTSA HD National Program
    D. Summary of Costs and Benefits of the HD National Program
    E. Program Flexibilities
    F. EPA and NHTSA Statutory Authorities
    G. Future HD GHG and Fuel Consumption Rulemakings
II. Final GHG and Fuel Consumption Standards for Heavy-Duty Engines 
and Vehicles
    A. What vehicles will be affected?
    B. Class 7 and 8 Combination Tractors
    C. Heavy-Duty Pickup Trucks and Vans
    D. Class 2b-8 Vocational Vehicles
    E. Other Standards
III. Feasibility Assessments and Conclusions
    A. Class 7-8 Combination Tractor
    B. Heavy-Duty Pickup Trucks and Vans
    C. Class 2b-8 Vocational Vehicles
IV. Final Regulatory Flexibility Provisions
    A. Averaging, Banking, and Trading Program
    B. Additional Flexibility Provisions
V. NHTSA and EPA Compliance, Certification, and Enforcement 
Provisions
    A. Overview
    B. Heavy-Duty Pickup Trucks and Vans
    C. Heavy-Duty Engines
    D. Class 7 and 8 Combination Tractors
    E. Class 2b-8 Vocational Vehicles
    F. General Regulatory Provisions
    G. Penalties
VI. How will this program impact fuel consumption, GHG emissions, 
and climate change?
    A. What methodologies did the agencies use to project GHG 
emissions and fuel consumption impacts?
    B. MOVES Analysis
    C. What are the projected reductions in fuel consumption and GHG 
emissions?
    D. Overview of Climate Change Impacts From GHG Emissions
    E. Changes in Atmospheric CO2 Concentrations, Global 
Mean Temperature, Sea Level Rise, and Ocean pH Associated With the 
Program's GHG Emissions Reductions
VII. How will this final action impact non-ghg emissions and their 
associated effects?
    A. Emissions Inventory Impacts
    B. Health Effects of Non-GHG Pollutants
    C. Environmental Effects of Non-GHG Pollutants
    D. Air Quality Impacts of Non-GHG Pollutants
VIII. What are the agencies' estimated cost, economic, and other 
impacts of the final program?
    A. Conceptual Framework for Evaluating Impacts
    B. Costs Associated With the Final Program
    C. Indirect Cost Multipliers
    D. Cost per Ton of Emissions Reductions
    E. Impacts of Reduction in Fuel Consumption
    F. Class Shifting and Fleet Turnover Impacts
    G. Benefits of Reducing CO2 Emissions
    H. Non-GHG Health and Environmental Impacts
    I. Energy Security Impacts
    J. Other Impacts
    K. The Effect of Safety Standards and Voluntary Safety 
Improvements on Vehicle Weight
    L. Summary of Costs and Benefits
    M. Employment Impacts
IX. Analysis of the Alternatives
    A. What are the alternatives that the agencies considered?
    B. How do these alternatives compare in overall GHG emissions 
reductions and fuel efficiency and cost?
    C. What is the agencies' decision regarding trailer standards?
X. Public Participation
XI. NHTSA's Record of Decision
    A. The Agency's Decision
    B. Alternatives Considered by NHTSA in Reaching Its Decision, 
Including the Environmentally Preferable Alternative
    C. Factors Balanced by NHTSA in Making Its Decision
    D. How the Factors and Considerations Balanced by NHTSA Entered 
Into Its Decision
    E. The Agency's Preferences Among Alternatives Based on Relevant 
Factors, Including Economic and Technical Considerations and Agency 
Statutory Missions
    F. Mitigation
XII. Statutory and Executive Order Reviews
XIII. Statutory Provisions and Legal Authority
    A. EPA
    B. NHTSA

I. Overview

A. Introduction

    EPA and NHTSA (``the agencies'') are announcing a first-ever 
program to reduce greenhouse gas (GHG) emissions and fuel consumption 
in the heavy-duty highway vehicle sector. This broad sector--ranging 
from large pickups to sleeper-cab tractors--together represent the 
second largest contributor to oil consumption and GHG emissions from 
the mobile source sector, after light-duty passenger cars and trucks. 
These are the second joint rules issued by the agencies, following on 
the April 1, 2010 standards to sharply reduce GHG emissions and fuel 
consumption from MY 2012-2016 passenger cars and light trucks 
(published on May 7, 2010 at 75 FR 25324).
    In a May 21, 2010 memorandum to the Administrators of EPA and NHTSA 
(and the Secretaries of Transportation and Energy), the President 
stated that ``America has the opportunity to lead the world in the 
development of a new generation of clean cars and trucks through 
innovative technologies and manufacturing that will spur economic 
growth and create high-quality domestic jobs, enhance our energy 
security, and improve our environment.'' 1 2 In the

[[Page 57108]]

May 2010 memorandum, the President specifically requested the 
Administrators of EPA and NHTSA to ``immediately begin work on a joint 
rulemaking under the Clean Air Act (CAA) and the Energy Independence 
and Security Act of 2007 (EISA) to establish fuel efficiency and 
greenhouse gas emissions standards for commercial medium-and heavy-duty 
on-highway vehicles and work trucks beginning with the 2014 model year 
(MY).'' In this final rulemaking, each agency is addressing this 
Memorandum by adopting rules under its respective authority that 
together comprise a coordinated and comprehensive HD National Program 
designed to address the urgent and closely intertwined challenges of 
reduction of dependence on oil, achievement of energy security, and 
amelioration of global climate change.
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    \1\ Improving Energy Security, American Competitiveness and Job 
Creation, and Environmental Protection Through a Transformation of 
Our Nation's Fleet of Cars And Trucks,'' Issued May 21, 2010, 
published at 75 FR 29399, May 26, 2010.
    \2\ The May 2010 Presidential Memorandum also directed EPA and 
NHTSA, in close coordination with the California Air Resources 
Board, to build on the National Program for 2012-2016 MY light-duty 
vehicles by developing and proposing coordinated light-duty vehicle 
standards for MY 2017-2025. The agencies have taken an initial step 
in this process, releasing a Joint Notice of Intent and Initial 
Joint Technical Assessment Report in September 2010 (75 FR 62739), 
and a Supplemental Notice of Intent (75 FR 76337). The agencies plan 
to issue a full light-duty vehicle proposal to extend the National 
Program to MY 2017-2025 in September 2011.
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    At the same time, the final program will enhance American 
competitiveness and job creation, benefit consumers and businesses by 
reducing costs for transporting goods, and spur growth in the clean 
energy sector.
    The HD National Program the agencies are finalizing today reflects 
a collaborative effort between the agencies, a range of public interest 
nongovernmental organizations (NGOs), the state of California and the 
regulated industry. At the time of the President's announcement, a 
number of major HD truck and engine manufacturers representing the vast 
majority of this industry, and the California Air Resources Board 
(California ARB), sent letters to EPA and NHTSA supporting the creation 
of a HD National Program based on a common set of principles. In the 
letters, the stakeholders committed to working with the agencies and 
with other stakeholders toward a program consistent with common 
principles, including:
    Increased use of existing technologies to achieve significant GHG 
emissions and fuel consumption reductions;
    A program that starts in 2014 and is fully phased in by 2018;
    A program that works towards harmonization of methods for 
determining a vehicle's GHG and fuel efficiency, recognizing the global 
nature of the issues and the industry;
    Standards that recognize the commercial needs of the trucking 
industry; and
    Incentives leading to the early introduction of advanced 
technologies.
    The final rules adopted today reflect these principles. The final 
HD National Program also builds on many years of heavy-duty engine and 
vehicle technology development to achieve what the agencies believe is 
the greatest degree of fuel consumption and GHG emission reduction 
appropriate, technologically and economically feasible, and cost-
effective for model years 2014-2018. In addition to taking aggressive 
steps that are reasonably possible now, based on the technological 
opportunities and pathways that present themselves during these model 
years, the agencies and industry will also continue learning about 
emerging opportunities for this complex sector to further reduce fuel 
consumption and GHG emission through future regulatory steps.
    Similarly, the agencies will participate in efforts to improve our 
ability to accurately characterize the actual in-use fuel consumption 
and emissions of this complex sector. As technologies progress in the 
coming years and as the agencies improve the regulatory tools to 
evaluate real world vehicle performance, we expect that we will develop 
a second phase of regulations to reinforce these initial rules and 
achieve further reductions in GHG emissions and fuel consumption 
reduction for the mid- and longer-term time frame (beyond 2018). The 
agencies are committed to working with all interested stakeholders in 
this effort and to the extent possible working towards alignment with 
similar programs being developed in Canada, Mexico, Europe, China, and 
Japan. In doing so, we will continue to evaluate many of the structural 
and technical decisions we are making in today's final action in the 
context of new technologies and the new regulatory tools that we expect 
to realize in the future.
    The regulatory program we are finalizing today is largely unchanged 
from the proposal the agencies made on November 30, 2010 (See 75 FR 
741512). The structure of the program and the stringency of the 
standards are essentially the same as proposed. We have made a number 
of changes to the testing requirements and reporting requirements to 
provide greater regulatory certainty and better align the NHTSA and EPA 
portions of the program. In response to comments, we have also made 
some changes to the averaging, banking and trading (ABT) provisions of 
the program that will make implementation of this final program more 
flexible for manufacturers. We have added provisions to further 
encourage the development of advanced technologies and to provide a 
more straightforward mechanism to certify engines and vehicles using 
innovative technologies. Finally in response to comments, we have made 
some technical changes to our emissions compliance model that results 
in different numeric standards for both combination tractors and 
vocational vehicles to more accurately characterize emissions while 
maintaining the same overall stringency and therefore expected costs 
and benefits of the program.
    Heavy-duty vehicles move much of the nation's freight and carry out 
numerous other tasks, including utility work, concrete delivery, fire 
response, refuse collection, and many more. Heavy-duty vehicles are 
primarily powered by diesel engines, although about 37 percent of these 
vehicles are powered by gasoline engines.\3\ Heavy-duty trucks \4\ have 
long been an important part of the goods movement infrastructure in 
this country and have experienced significant growth over the last 
decade related to increased imports and exports of finished goods and 
increased shipping of finished goods to homes through Internet 
purchases.
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    \3\ References in this preamble to ``gasoline'' engines (and the 
vehicles powered by them) generally include other Otto-cycle engines 
as well, such as those fueled by ethanol and natural gas, except in 
contexts that are clearly gasoline-specific.
    \4\ In this rulemaking, EPA and NHTSA use the term ``truck'' in 
a general way, referring to all categories of regulated heavy-duty 
highway vehicles (including buses). As such, the term is generally 
interchangeable with ``heavy-duty vehicle.''
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    The heavy-duty sector is extremely diverse in several respects, 
including types of manufacturing companies involved, the range of sizes 
of trucks and engines they produce, the types of work the trucks are 
designed to perform, and the regulatory history of different 
subcategories of vehicles and engines. The current heavy-duty fleet 
encompasses vehicles from the ``18-wheeler'' combination tractors one 
sees on the highway to school and transit buses, to vocational vehicles 
such as utility service trucks, as well as the largest pickup trucks 
and vans.
    For purposes of this preamble, the term ``heavy-duty'' or ``HD'' is 
used to apply to all highway vehicles and engines that are not within 
the range of light-duty vehicles, light-duty trucks, and medium-duty 
passenger vehicles (MDPV) covered by the GHG and Corporate Average Fuel 
Economy (CAFE) standards issued for MY 2012-2016.\5\ It also does not 
include

[[Page 57109]]

motorcycles. Thus, in this rulemaking, unless specified otherwise, the 
heavy-duty category incorporates all vehicles with a gross vehicle 
weight rating above 8,500 pounds, and the engines that power them, 
except for MDPVs.\6\
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    \5\ Light-Duty Vehicle Greenhouse Gas Emission Standards and 
Corporate Average Fuel Economy Standards; Final Rule 75 FR 25323, 
May 7, 2010.
    \6\ The CAA defines heavy-duty as a truck, bus or other motor 
vehicles with a gross vehicle weight rating exceeding 6,000 pounds 
(CAA section 202(b)(3)). The term HD as used in this action refers 
to a subset of these vehicles and engines.
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    The agencies proposed to cover all segments of the heavy-duty 
category above, except with respect to recreational vehicles (RVs or 
motor homes). We note that the Energy Independence and Security Act of 
2007 requires NHTSA to set standards for ``commercial medium- and 
heavy-duty on-highway vehicles and work trucks.'' \7\ The standards 
that EPA is finalizing today cover recreational on-highway vehicles, 
while NHTSA proposed not to include recreational vehicles based on an 
interpretation of the term ``commercial medium- and heavy-duty on-
highway commercial'' vehicles. NHTSA stated in the NPRM that 
recreational vehicles are non-commercial, and therefore outside of the 
term and the scope of its rule.
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    \7\ 49 U.S.C. 32902(k)(2). ``Commercial medium- and heavy-duty 
on-highway vehicles'' are defined as on-highway vehicles with a 
gross vehicle weight rating of 10,000 pounds or more, while ``work 
trucks'' are defined as vehicles rated between 8,500 and 10,000 
pounds gross vehicle weight that are not MDPVs. See 49 U.S.C. 
32901(a)(7) and (a)(19).
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    Oshkosh Corporation commented that this interpretation did not 
match the statutory definition of the term in EISA, which defines 
``commercial medium- and heavy-duty on-highway vehicle'' by weight 
only,\8\ and that therefore the agency's interpretation of the term 
should be explicitly broadened to include all vehicles, and more than 
only vehicles that are not engaged in interstate commerce as defined by 
the Federal Motor Carrier Safety Administration in 49 CFR part 202. 
Alternatively, Oshkosh suggested that if NHTSA followed the definition 
provided in EISA, which makes no direct reference to the concept of 
``commercial,'' there would be no logical reason to exclude RVs based 
on that definition.
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    \8\ See 49 U.S.C. 32902(k)(2), Note 7 above.
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    NHTSA has considered Oshkosh's comment and reconsidered its 
interpretation that effectively read words into the statutory 
definition. Given the very wide variety of vehicles contained in the HD 
fleet, reading those words into the definition and thereby excluding 
certain types of vehicles could create illogical results, i.e., 
treating similar vehicles differently. Therefore, NHTSA will adhere to 
the statutory definition contained in EISA for this rulemaking. 
However, as RVs were not included by NHTSA in the proposed regulation 
in the NPRM, they are not within the scope and must be excluded in 
NHTSA's portion of the final program. Accordingly, NHTSA will address 
this issue in the next rulemaking. However, as noted, RVs are subject 
to the CO2 standards for vocational vehicles.
    Setting fuel consumption standards for the heavy-duty sector, 
pursuant to NHTSA's EISA authority, will also improve our energy and 
national security by reducing our dependence on foreign oil, which has 
been a national objective since the first oil price shocks in the 
1970s. Net petroleum imports now account for approximately 49-51 
percent of U.S. petroleum consumption. World crude oil production is 
highly concentrated, exacerbating the risks of supply disruptions and 
price shocks as the recent unrest in North Africa and the Persian Gulf 
highlights. Recently, oil prices have been over $100 per barrel, 
gasoline and diesel fuel prices in excess of $4 per gallon, causing 
financial hardship for many families and businesses. The export of U.S. 
assets in exchange for oil imports continues to be an important 
component of the historically unprecedented U.S. trade deficits. 
Transportation accounts for about 72 percent of U.S. petroleum 
consumption. Heavy-duty vehicles account for about 17 percent of 
transportation oil use, which means that they alone account for about 
12 percent of all U.S. oil consumption.\9\
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    \9\ In 2009 Source: EIA Annual Energy Outlook 2010 released May 
11, 2010.
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    Setting GHG emissions standards for the heavy-duty sector will help 
to ameliorate climate change. The EPA Administrator found after a 
thorough examination of the scientific evidence on the causes and 
impact of current and future climate change, and careful review of 
public comments, that the science compellingly supports a positive 
finding that atmospheric concentrations of six greenhouse gases taken 
in combination result in air pollution which may reasonably be 
anticipated to endanger both public health and welfare and that the 
combined emissions of these greenhouse gases from new motor vehicles 
and engines contributes to the greenhouse gas air pollution that 
endangers public health and welfare. In her finding, the Administrator 
carefully studied and relied heavily upon the major findings and 
conclusions from the recent assessments of the U.S. Climate Change 
Science Program and the U.N. Intergovernmental Panel on Climate Change. 
74 FR 66496, December 15, 2009. As summarized in the Technical Support 
Document for EPA's Endangerment and Cause or Contribute Findings under 
section 202(a) of the Clean Air Act, anthropogenic emissions of GHGs 
are very likely (a 90 to 99 percent probability) the cause of most of 
the observed global warming over the last 50 years.\10\ Primary GHGs of 
concern are carbon dioxide (CO2), methane (CH4), 
nitrous oxide (N2O), hydrofluorocarbons (HFCs), 
perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). 
Mobile sources emitted 31 percent of all U.S. GHGs in 2007 
(transportation sources, which do not include certain off-highway 
sources, account for 28 percent) and have been the fastest-growing 
source of U.S. GHGs since 1990.\11\ Mobile sources addressed in EPA's 
endangerment and contribution findings under CAA section 202(a)--light-
duty vehicles, heavy-duty trucks, buses, and motorcycles--accounted for 
23 percent of all U.S. GHG emissions in 2007.\12\ Heavy-duty vehicles 
emit CO2, CH4, N2O, and HFCs and are 
responsible for nearly 19 percent of all mobile source GHGs (nearly 6 
percent of all U.S. GHGs) and about 25 percent of section 202(a) mobile 
source GHGs. For heavy-duty vehicles in 2007, CO2 emissions 
represented more than 99 percent of all GHG emissions (including 
HFCs).\13\
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    \10\ U.S. EPA. (2009). ``Technical Support Document for 
Endangerment and Cause or Contribute Findings for Greenhouse Gases 
Under Section 202(a) of the Clean Air Act'' Washington, DC, 
available at Docket: EPA-HQ-OAR-2009-0171-11645, and at http://epa.gov/climatechange/endangerment.html.
    \11\ U.S. Environmental Protection Agency. 2009. Inventory of 
U.S. Greenhouse Gas Emissions and Sinks: 1990-2007. EPA 430-R-09-
004. Available at http://epa.gov/climatechange/emissions/downloads09/GHG2007entire_report-508.pdf.
    \12\ See Endangerment TSD, Note 10, above, at pp. 180-194.
    \13\ U.S. Environmental Protection Agency. 2009. Inventory of 
U.S. Greenhouse Gas Emissions and Sinks: See Note 11, above.
---------------------------------------------------------------------------

    In developing this HD National program, the agencies have worked 
with a large and diverse group of stakeholders representing truck and 
engine manufacturers, trucking fleets, environmental organizations, and 
states including the State of California.\14\ Further, it is our 
expectation based on our ongoing work with the State of California that 
the California ARB will

[[Page 57110]]

be able to adopt regulations equivalent in practice to those of this HD 
National Program, just as it has done for past EPA regulation of heavy-
duty trucks and engines. NHTSA and EPA have been working with 
California ARB to enable that outcome.
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    \14\ Pursuant to DOT Order 2100.2, NHTSA has docketed a 
memorandum recording those meetings that it attended and documents 
submitted by stakeholders which formed a basis for this action and 
which can be made publicly available in its docket for this 
rulemaking. DOT Order 2100.2 is available at http://www.reg-group.com/library/DOT2100-2.PDF.
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    In light of the industry's diversity, and consistent with the 
recommendations of the National Academy of Sciences (NAS) as discussed 
further below, the agencies are adopting a HD National Program that 
recognizes the different sizes and work requirements of this wide range 
of heavy-duty vehicles and their engines. NHTSA's final fuel 
consumption standards and EPA's final GHG standards apply to 
manufacturers of the following types of heavy-duty vehicles and their 
engines; the final provisions for each of these are described in more 
detail below in this section:
     Heavy-duty Pickup Trucks and Vans.
     Combination Tractors.
     Vocational Vehicles.
    As in the light-duty 2012-2016 MY vehicle rule, EPA's and NHTSA's 
final standards for the heavy-duty sector are largely harmonized with 
one another due to the close and direct relationship between improving 
the fuel efficiency of these vehicles and reducing their CO2 
tailpipe emissions. For all vehicles that consume carbon-based fuels, 
the amount of CO2 exhaust emissions is essentially constant 
per gallon for a given type of fuel that is consumed. The more 
efficient a heavy-duty truck is in completing its work, the lower its 
environmental impact will be, because the less fuel consumed to move 
cargo a given distance, the less CO2 that truck emits 
directly into the air. The technologies available for improving fuel 
efficiency, and therefore for reducing both CO2 emissions 
and fuel consumption, are one and the same.\15\ Because of this close 
technical relationship, NHTSA and EPA have been able to rely on 
jointly-developed assumptions, analyses, and analytical conclusions to 
support the standards and other provisions that NHTSA and EPA are 
adopting under our separate legal authorities.
---------------------------------------------------------------------------

    \15\ However, as discussed below, in addition to addressing 
CO2, the EPA's final standards also include provisions to 
address other GHGs (nitrous oxide, methane, and air conditioning 
refrigerant emissions). See Section II.
---------------------------------------------------------------------------

    This program is based on standards for direct exhaust emissions 
from engines and vehicles. In characterizing the overall emissions 
impacts, benefits and costs of the program, analyses of air pollutant 
emissions from upstream sources have been conducted. In this action, 
the agencies use the term upstream to include emissions from the 
production and distribution of fuel. A summary of the analysis of 
upstream emissions can be found in Section VI.C of this preamble, and 
further details are available in Chapter 5 of the RIA.
    The timelines for the implementation of the final NHTSA and EPA 
standards are also closely coordinated. EPA's final GHG emission 
standards will begin in model year 2014. In order to provide for the 
four full model years of regulatory lead time required by EISA, as 
discussed in Section 0 below, NHTSA's final fuel consumption standards 
will be voluntary in model years 2014 and 2015, becoming mandatory in 
model year 2016, except for diesel engine standards which will be 
voluntary in model years 2014, 2015 and 2016, becoming mandatory in 
model year 2017. Both agencies are also allowing for early compliance 
in model year 2013. A detailed discussion of how the final standards 
are consistent with each agency's respective statutory requirements and 
authorities is found later in this preamble.
    Allison Transmission stated that sufficient time must be taken 
before issuing the final rules in order to ensure that the standards 
are supportable. As explained in Sections II and III below, as well as 
in the RIA, the agencies believe there is sufficient lead time to meet 
all of the standards adopted in today's rules. For those areas for 
which the agencies have determined that insufficient time is available 
to develop appropriate standards, such as for trailers, the agencies 
are not including regulations as part of this initial program.
    NHTSA received several comments related to the timing of the 
implementation of its fuel consumption standards. The Engine 
Manufacturers Association (EMA), the National Automobile Dealers 
Association (NADA), The Volvo Group (Volvo), and Navistar argued that 
the timing of NHTSA's standards violated the lead time requirement of 
49 U.S.C. 32902(k)(3)(A), which states that standards under the new 
medium- and heavy-duty program shall have ``not less than 4 full model 
years of regulatory lead-time.'' The commenters seemed to interpret the 
voluntary program as the imposition of regulation upon industry. NADA 
described NHTSA's standards during the voluntary period as 
``mandates.''
    NHTSA has reviewed this issue and believes that the regulatory 
schedule is consistent with the lead time requirement of Section 
32902(k)(3). To clarify, NHTSA will not be imposing a mandatory 
regulatory program until 2016, and none of the voluntary standards will 
be ``mandates.'' As described in later sections, the voluntary 
standards would only apply to a manufacturer if it makes the voluntary 
and affirmative choice to opt-in to the program. \16\ Mandatory NHTSA 
standards will first come into effect in 2016, giving industry four 
full years of lead time with the NHTSA fuel consumption standards.
---------------------------------------------------------------------------

    \16\ Prior to or at the same time that a manufacturer submits 
its first application for a certificate of conformity; See Section V 
below.
---------------------------------------------------------------------------

    EMA, NADA, and Navistar also argued that the proposed standards 
would violate the stability requirement of 49 U.S.C. 32902(k)(3)(B), 
which states that they shall have ``not less than 3 full model years of 
regulatory stability.'' EMA stated that since there are HD emission 
standards taking effect in 2013, the 2014 implementation date for this 
rule would violate the stability requirements. NADA argued that the MY 
2014-2017/2018 phase-in period was inadequate to fulfill the stability 
requirement.
    Congress has not spoken directly to the meaning of the words 
``regulatory stability.'' NHTSA believes that the ``regulatory 
stability'' requirement exists to ensure that manufacturers will not be 
subject to new standards in repeated rulemakings too rapidly, given 
that Congress did not include a minimum duration period for the MD/HD 
standards.\17\ NHTSA further believes that standards, which as set 
provide for increasing stringency during the period that the standards 
are applicable under this rule to be the maximum feasible during the 
regulatory period, are within the meaning of the statute. In this 
statutory context, NHTSA interprets the phrase ``regulatory stability'' 
in Section 32902(k)(3)(B) as requiring that the standards remain in 
effect for three years before they may be increased by amendment. It 
does not prohibit standards which contain pre-determined stringency 
increases.
---------------------------------------------------------------------------

    \17\ In contrast, light-duty standards must remain in place for 
``at least 1, but not more than 5, model years.'' 23902(b)(3)(B).
---------------------------------------------------------------------------

    As laid out in Section II below, NHTSA's final standards follow 
different phase-in schedules based on differences between the 
regulatory categories. Consistent with NHTSA's statutory obligation to 
implement a program designed to achieve the maximum feasible fuel 
efficiency improvement, the standards increase in stringency based upon 
increasing fleet penetration rates for the available technologies. The 
NPRM proposed phase-in schedules aligned with EPA's,

[[Page 57111]]

some of which followed pre-determined stringency increases. The NPRM 
also noted that NHTSA was considering alternate standards that would 
not change in stringency during the time frame when the regulations are 
effective for those standards that increased throughout the mandatory 
program. As described in Section II below, the final rule includes the 
proposed alternate standards for those standards that follow such a 
stringency phase-in path. Therefore, NHTSA believes that the final rule 
provides ample stability for each standard.
    Each standard, associated phase-in schedule, and alternative 
standard implemented by this final rule was noticed in the NPRM. Those 
fuel consumption standards that become mandatory in 2017 will remain in 
effect through at least 2019. This further ensures that the fuel 
consumption standards in this rule will remain in effect for at least 
three years, providing the statutorily-mandated three full years of 
regulatory stability, and ensuring that manufacturers will not be 
subject to new or amended standards too rapidly. (The greenhouse gas 
emission standards remain in effect unless and until amended in all 
later model years in any case.) Therefore, NHTSA believes the 
commenters' concern about regulatory stability is addressed in the 
structure of the rule.
    Neither EPA nor NHTSA is adopting standards at this time for GHG 
emissions or fuel consumption, respectively, for heavy-duty commercial 
trailers or for vehicles or engines manufactured by small businesses. 
The agencies recognize that aerodynamic and tire rolling resistance 
improvements to trailers represent a significant opportunity to reduce 
fuel consumption and GHGs as evidenced, among other things, by the work 
of the EPA SmartWay program. While we are deferring action today on 
setting trailer standards, the agencies are committed to moving forward 
to create a regulatory program for trailers that would complement the 
current vehicle program. See Section IX for more details on the 
agencies' decisions regarding trailers, and Sections II and XII for 
more details on the agencies' decisions regarding small businesses.
    The agencies have analyzed in detail the projected costs, fuel 
savings, and benefits of the final GHG and fuel consumption standards. 
Table I-1 shows estimated lifetime discounted program costs (including 
technological outlays), fuel savings, and benefits for all heavy-duty 
vehicles projected to be sold in model years 2014-2018 over these 
vehicles' lives. Section I.D includes additional information about this 
analysis.

 Table I-1--Estimated Lifetime Discounted Costs, Fuel Savings, Benefits,
    and Net Benefits for 2014-2018 Model Year Heavy-Duty Vehicles a b
                            [Billions, 2009$]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
              Lifetime Present Value \c\--3% Discount Rate
------------------------------------------------------------------------
Program Costs..................................................     $8.1
Fuel Savings...................................................       50
Benefits.......................................................      7.3
Net Benefits\d\................................................       49
------------------------------------------------------------------------
                 Annualized Value \e\--3% Discount Rate
------------------------------------------------------------------------
Annualized Costs...............................................      0.4
Fuel Savings...................................................      2.2
Annualized Benefits............................................      0.4
Net Benefits \d\...............................................      2.2
------------------------------------------------------------------------
              Lifetime Present Value \c\--7% Discount Rate
------------------------------------------------------------------------
Program Costs..................................................      8.1
Fuel Savings...................................................       34
Benefits.......................................................      6.7
Net Benefits \d\...............................................       33
------------------------------------------------------------------------
                 Annualized Value \e\--7% Discount Rate
------------------------------------------------------------------------
Annualized Costs...............................................      0.6
Fuel Savings...................................................      2.6
Annualized Benefits............................................      0.5
Net Benefits \d\...............................................      2.5
------------------------------------------------------------------------
Notes:
a The agencies estimated the benefits associated with four different
  values of a one ton CO2 reduction (model average at 2.5% discount
  rate, 3%, and 5%; 95th percentile at 3%), which each increase over
  time. For the purposes of this overview presentation of estimated
  costs and benefits, however, we are showing the benefits associated
  with the marginal value deemed to be central by the interagency
  working group on this topic: the model average at 3% discount rate, in
  2009 dollars. Section VIII.F provides a complete list of values for
  the 4 estimates.
b Note that net present value of reduced GHG emissions is calculated
  differently than other benefits. The same discount rate used to
  discount the value of damages from future emissions (SCC at 5, 3, and
  2.5 percent) is used to calculate net present value of SCC for
  internal consistency. Refer to Section VIII.F for more detail.
c Present value is the total, aggregated amount that a series of
  monetized costs or benefits that occur over time is worth now (in year
  2009 dollar terms), discounting future values to the present.
d Net benefits reflect the fuel savings plus benefits minus costs.
e The annualized value is the constant annual value through a given time
  period (2012 through 2050 in this analysis) whose summed present value
  equals the present value from which it was derived.

B. Building Blocks of the Heavy-Duty National Program

    The standards that are being adopted in this notice represent the 
first time that NHTSA and EPA are regulating the heavy-duty sector for 
fuel consumption and GHG emissions, respectively. The HD National 
Program is rooted in EPA's prior regulatory history, the SmartWay[reg] 
Transport Partnership program, and extensive technical and engineering 
analyses done at the federal level. This section summarizes some of the 
most important of these precursors and foundations for this HD National 
Program.
(1) EPA's Traditional Heavy-Duty Regulatory Program
    Since the 1980s, EPA has acted several times to address tailpipe 
emissions of criteria pollutants and air toxics from heavy-duty 
vehicles and engines. During the last 18 years, these programs have 
primarily addressed emissions of particulate matter (PM) and the 
primary ozone precursors, hydrocarbons (HC) and oxides of nitrogen 
(NOX). These programs have successfully achieved significant 
and cost-effective reductions in emissions and associated health and 
welfare benefits to the nation. They have been structured in ways that 
account for the varying circumstances of the engine and truck 
industries. As required by the CAA, the emission standards implemented 
by these programs include standards that apply at the time that the 
vehicle or engine is sold as well as standards that apply in actual 
use. As a result of these programs, new vehicles meeting current 
emission standards will emit 98 percent less NOX and 99 
percent less PM than new trucks 20 years ago. The resulting emission 
reductions provide significant public health and welfare benefits. The 
most recent EPA regulations which were fully phased-in in 2010, the 
monetized health and welfare benefits alone are projected to be greater 
than $70 billion in 2030--benefits far exceeding compliance costs and 
not including the unmonetized benefits resulting from reductions in air 
toxics and ozone precursors (66 FR 5002, January 18, 2001).
    EPA's overall program goal has always been to achieve emissions 
reductions from the complete vehicles that operate on our roads. The 
agency has often accomplished this goal for many heavy-duty truck 
categories through the regulation of heavy-duty engine emissions. A key 
part of this success has been the development over many years of a 
well-established, representative, and robust set of engine

[[Page 57112]]

test procedures that industry and EPA now routinely use to measure 
emissions and determine compliance with emission standards. These test 
procedures in turn serve the overall compliance program that EPA 
implements to help ensure that emissions reductions are being achieved. 
By isolating the engine from the many variables involved when the 
engine is installed and operated in a HD vehicle, EPA has been able to 
accurately address the contribution of the engine alone to overall 
emissions. The agencies discuss below how the final program 
incorporates the existing engine-based approach used for criteria 
pollutant regulations, as well as new vehicle-based approaches.
(2) NHTSA's Responsibilities To Regulate Heavy-Duty Fuel Efficiency 
under EISA
    With the passage of the EISA in December 2007, Congress laid out a 
framework developing the first fuel efficiency regulations for HD 
vehicles. As codified at 49 U.S.C. 32902(k), EISA requires NHTSA to 
develop a regulatory system for the fuel efficiency of commercial 
medium-duty and heavy-duty on-highway vehicles and work trucks in three 
steps: a study by NAS, a study by NHTSA,\18\ and a rulemaking to 
develop the regulations themselves.
---------------------------------------------------------------------------

    \18\ Factors and Considerations for Establishing a Fuel 
Efficiency Regulatory Program for Commercial Medium- and Heavy-Duty 
Vehicles, October 2010, available at http://www.nhtsa.gov/staticfiles/rulemaking/pdf/cafe/NHTSA_Study_Trucks.pdf.
---------------------------------------------------------------------------

    Specifically, section 102 of EISA, codified at 49 U.S.C. 
32902(k)(2), states that not later than two years after completion of 
the NHTSA study, DOT (by delegation, NHTSA), in consultation with the 
Department of Energy (DOE) and EPA, shall develop a regulation to 
implement a ``commercial medium-duty and heavy-duty on-highway vehicle 
and work truck fuel efficiency improvement program designed to achieve 
the maximum feasible improvement.'' NHTSA interprets the timing 
requirements as permitting a regulation to be developed earlier, rather 
than as requiring the agency to wait a specified period of time.
    Congress specified that as part of the ``HD fuel efficiency 
improvement program designed to achieve the maximum feasible 
improvement,'' NHTSA must adopt and implement:
    Appropriate test methods;
    Measurement metrics;
    Fuel economy standards; \19\ and
---------------------------------------------------------------------------

    \19\ In the context of 49 U.S.C. 32902(k), NHTSA interprets 
``fuel economy standards'' as referring not specifically to miles 
per gallon, as in the light-duty vehicle context, but instead more 
broadly to account as accurately as possible for MD/HD fuel 
efficiency. While it is a metric that NHTSA considered for setting 
MD/HD fuel efficiency standards, the agency recognizes that miles 
per gallon may not be an appropriate metric given the work that MD/
HD vehicles are manufactured to do. NHTSA is thus finalizing 
alternative metrics as discussed further below.
---------------------------------------------------------------------------

    Compliance and enforcement protocols.
    Congress emphasized that the test methods, measurement metrics, 
standards, and compliance and enforcement protocols must all be 
appropriate, cost-effective, and technologically feasible for 
commercial medium-duty and heavy-duty on-highway vehicles and work 
trucks. NHTSA notes that these criteria are different from the ``four 
factors'' of 49 U.S.C. 32902(f) \20\ that have long governed NHTSA's 
setting of fuel economy standards for passenger cars and light trucks, 
although many of the same issues are considered under each of these 
provisions.
---------------------------------------------------------------------------

    \20\ 49 U.S.C. 32902(f) states that ``When deciding maximum 
feasible average fuel economy under this section, [NHTSA] shall 
consider technological feasibility, economic practicability, the 
effect of other motor vehicle standards of the Government on fuel 
economy, and the need of the United States to conserve energy.''
---------------------------------------------------------------------------

    Congress also stated that NHTSA may set separate standards for 
different classes of HD vehicles, which the agency interprets broadly 
to allow regulation of HD engines in addition to HD vehicles, and 
provided requirements new to 49 U.S.C. 32902 in terms of timing of 
regulations, stating that the standards adopted as a result of the 
agency's rulemaking shall provide not less than four full model years 
of regulatory lead time, and three full model years of regulatory 
stability.
(3) National Academy of Sciences Report on Heavy-Duty Technology
    In April 2010 as mandated by Congress in EISA, the National 
Research Council (NRC) under NAS issued a report to NHTSA and to 
Congress evaluating medium-duty and heavy-duty truck fuel efficiency 
improvement opportunities, titled ``Technologies and Approaches to 
Reducing the Fuel Consumption of Medium- and Heavy-duty Vehicles.'' 
\21\ This study covers the same universe of heavy-duty vehicles that is 
the focus of this final rulemaking--all highway vehicles that are not 
light-duty, MDPVs, or motorcycles. The agencies have carefully 
evaluated the research supporting this report and its recommendations 
and have incorporated them to the extent practicable in the development 
of this rulemaking.
---------------------------------------------------------------------------

    \21\ Committee to Assess Fuel Economy Technologies for Medium- 
and Heavy-Duty Vehicles; National Research Council; Transportation 
Research Board (2010). ``Technologies and Approaches to Reducing the 
Fuel Consumption of Medium- and Heavy-Duty Vehicles,'' (hereafter, 
``NAS Report''). Washington, DC, The National Academies Press. 
Available electronically from the National Academies Press Website 
at http://www.nap.edu/catalog.php?record_id=12845 (last accessed 
September 10, 2010).
---------------------------------------------------------------------------

    The NAS report is far reaching in its review of the technologies 
that are available and which may become available in the future to 
reduce fuel consumption from medium and heavy-duty vehicles. In 
presenting the full range of technical opportunities the report 
includes technologies which may not be available until 2020 or even 
further into the future. As such, the report provides not only a 
valuable list of off the shelf technologies from which the agencies 
have drawn in developing this near-term 2014-2018 program consistent 
with statutory authorities and with the set of principles set forth by 
the President, but the report also provides a road map the agencies can 
use as we look to develop future regulations for this sector. A review 
of the technologies in the NAS report makes clear that there are not 
only many technologies readily available today to achieve important 
reductions in fuel consumption, like the ones we used in developing the 
2014-2018 program, but there are also great opportunities for even 
larger reductions in the future through the development of advanced 
hybrid drive systems and sophisticated engine technologies such as 
Rankine waste heat recovery. The agencies will again make extensive use 
of this report when we move forward to develop the next phase of 
regulations for medium and heavy-duty vehicles.
    Allison Transmission commented that NHTSA (implicitly, both 
agencies) had improperly relied on the NAS report and failed to do 
sufficient independent analysis, which Allison claimed did not meet the 
statutory obligation to provide an adequate basis for the rule. First, 
an agency does not improperly delegate its authority or judgment merely 
by using work performed by outside parties as the factual basis for its 
decision making. See U.S. Telecom Ass'n v. FCC, 359 F.3d 554, 568 (DC 
Cir. 2004); United Steelworkers of Am. v. Marshall, 647 F.2d 1189, 
1216-17 (DC Cir. 1980). Here, although EPA and NHTSA carefully 
considered the NAS report, the agencies' consideration and use of the 
report was not uncritical and the agencies exercised reasonable 
independent judgment in developing the proposed and final rules. 
Consistent with EISA's direction, NAS submitted a report evaluating MD/
HD fuel economy standards to NHTSA in March of 2010.

[[Page 57113]]

Indeed, many commenters argued that the agencies should have adopted 
more of the NAS report recommendations. The agencies reviewed the 
findings and recommendations of the NAS report when developing the 
proposed rules, as was clearly intended by Congress, but also conducted 
an independent study, as described throughout the record to the 
proposal and summarized in Section X of the NPRM, 75 FR at 74351-56. In 
conducting its analysis of the NAS report, the agencies found that 
several key recommendations, such as the use of fuel efficiency 
metrics, were the best approach to implementing the new program. 
However, the agencies rejected other recommendations of the NAS report, 
for example, by proposing separate regulation of engines and vehicles 
and the regulation of large manufacturers.
(4) The NHTSA and EPA Light-Duty National GHG and Fuel Economy Program
    On May 7, 2010, EPA and NHTSA finalized the first-ever National 
Program for light-duty cars and trucks, which set GHG emissions and 
fuel economy standards for model years 2012-2016 (See 75 FR 25324). The 
agencies have used the light-duty National Program as a model for this 
final HD National Program in many respects. This is most apparent in 
the case of heavy-duty pickups and vans, which are very similar to the 
light-duty trucks addressed in the light-duty National Program both 
technologically as well as in terms of how they are manufactured (i.e., 
the same company often makes both the vehicle and the engine). For 
these vehicles, there are close parallels to the light-duty program in 
how the agencies have developed our respective final standards and 
compliance structures, although, as discussed below, the technologies 
applied to light-duty trucks are not invariably applicable to heavy-
duty pickups and vans at the same penetration rates in the lead time 
afforded in this heavy-duty action. Another difference is that each 
agency adopts standards based on attributes other than vehicle 
footprint, as discussed below.
    Due to the diversity of the remaining HD vehicles, there are fewer 
parallels with the structure of the light-duty program. However, the 
agencies have maintained the same collaboration and coordination that 
characterized the development of the light-duty program. Most notably, 
as with the light-duty program, manufacturers will be able to design 
and build vehicles to meet a closely coordinated, harmonized national 
program, and avoid unnecessarily duplicative testing and compliance 
burdens.
(5) EPA's SmartWay Program
    EPA's voluntary SmartWay Transport Partnership program encourages 
shipping and trucking companies to take actions that reduce fuel 
consumption and CO2 by working with the shipping community 
and the freight sector to identify low carbon strategies and 
technologies, and by providing technical information, financial 
incentives, and partner recognition to accelerate the adoption of these 
strategies. Through the SmartWay program, EPA has worked closely with 
truck manufacturers and truck fleets to develop test procedures to 
evaluate vehicle and component performance in reducing fuel consumption 
and has conducted testing and has established test programs to verify 
technologies that can achieve these reductions. Over the last six 
years, EPA has developed hands-on experience testing the largest heavy-
duty trucks and evaluating improvements in tire and vehicle aerodynamic 
performance. In 2010, according to vehicle manufacturers, approximately 
five percent of new combination heavy-duty trucks will meet the 
SmartWay performance criteria demonstrating that they represent the 
pinnacle of current heavy-duty truck reductions in fuel consumption.
    In developing this HD National Program, the agencies have drawn 
from the SmartWay experience, as discussed in detail both in Sections 
II and III below (e.g., developing test procedures to evaluate trucks 
and truck components) but also in the RIA (estimating performance 
levels from the application of the best available technologies 
identified in the SmartWay program). These technologies provide part of 
the basis for the GHG emission and fuel consumption standards in this 
rulemaking for certain types of new heavy-duty Class 7 and 8 
combination tractors.
    In addition to identifying technologies, the SmartWay program 
includes operational approaches that truck fleet owners as well as 
individual drivers and their freight customers can incorporate, that 
the NHTSA and EPA believe will complement the final standards. These 
include such approaches as improved logistics and driver training, as 
discussed in the RIA. This approach is consistent with the one of the 
three alternative approaches that the NAS recommended be considered. 
The three approaches were raising fuel taxes, relaxing truck size and 
weight restrictions, and encouraging incentives to disseminate 
information to inform truck drivers about the relationship between 
driving behavior and fuel savings. Taxes and truck size and weight 
limits are mandated by public law; as such, these options are outside 
EPA's and NHTSA's authority to implement. However, complementary 
operational measures like driver training, which SmartWay does promote, 
can complement the final standards and also provide benefits for the 
existing truck fleet, furthering the public policy objectives of 
addressing energy security and climate change.
(6) Environment Canada
    The Government of Canada's Department of the Environment 
(Environment Canada) assisted EPA's development of this rulemaking by 
conducting emissions testing of heavy-duty vehicles at their test 
facilities to gather data on a range of possible test cycles, and to 
evaluate the impact of certain emissions reduction technologies. 
Environment Canada also facilitated the evaluation of heavy-duty 
vehicle aerodynamic properties at Canada's National Research Council 
wind tunnel, and during coastdown testing.
    We expect the technical collaboration with Environment Canada to 
continue as we implement testing and compliance verification procedures 
for this rulemaking. We may also begin to develop a knowledge base 
enabling improvement upon this regulatory framework for model years 
beyond 2018 (for example, improvements to the means of demonstrating 
compliance). We also expect to continue our collaboration with 
Environment Canada on compliance issues.
    Collaboration with Environment Canada is taking place under the 
Canada-U.S. Air Quality Committee.

C. Summary of the Final EPA and NHTSA HD National Program

    When EPA first addressed emissions from heavy-duty trucks in the 
1980s, it established standards for engines, based on the amount of 
work performed (grams of pollutant per unit of work, expressed as grams 
per brake horsepower-hour or g/bhp-hr).\22\ This

[[Page 57114]]

approach recognized the fact that engine characteristics are the 
dominant determinant of the types of emissions generated, and engine-
based technologies (including exhaust aftertreatment systems) need to 
be the focus for addressing those emissions. Vehicle-based 
technologies, in contrast, have less influence on overall truck 
emissions of the pollutants that EPA has regulated in the past. The 
engine testing approach also recognized the relatively small number of 
distinct heavy-duty engine designs, as compared to the extremely wide 
range of truck designs. EPA concluded at that time that any incremental 
gain in conventional emission control that could be achieved through 
regulation of the complete vehicle would be small in comparison to the 
cost of addressing the many variants of complete trucks that make up 
the heavy-duty sector--smaller and larger vocational vehicles for 
dozens of purposes, various designs of combination tractors, and many 
others.
---------------------------------------------------------------------------

    \22\ The term ``brake power'' refers to engine torque and power 
as measured at the interface between the engine's output shaft and 
the dynamometer. This contrasts with ``indicated power'', which is a 
calculated value based on the pressure dynamics in the combustion 
chamber, not including internal losses that occur due to friction 
and pumping work. Since the measurement procedure inherently 
measures brake torque and power, the final regulations refer simply 
to g/hp-hr. This is consistent with EPA's other emission control 
programs, which generally include standards in g/kW-hr.
---------------------------------------------------------------------------

    Addressing GHG emissions and fuel consumption from heavy-duty 
trucks, however, requires a different approach. Reducing GHG emissions 
and fuel consumption requires increasing the inherent efficiency of the 
engine as well as making changes to the vehicles to reduce the amount 
of work demanded from the engine in order to move the truck down the 
road. A focus on the entire vehicle is thus required. For example, in 
addition to the basic emissions and fuel consumption levels of the 
engine, the aerodynamics of the vehicle can have a major impact on the 
amount of work that must be performed to transport freight at common 
highway speeds. For this first rulemaking, the agencies proposed a 
complementary engine and vehicle approach in order to achieve the 
maximum feasible near-term reductions.
    NHTSA received comments on the proposal to create complementary 
engine and vehicle standards. Volvo and Daimler argued that EISA 
limited NHTSA's authority to the regulation of completed vehicles and 
did not give NHTSA authority to regulate engines. 49 U.S.C. 32902(k)(2) 
grants NHTSA broad authority to regulate this sector, stating simply 
that the Secretary ``shall determine in a rulemaking proceeding how to 
implement a commercial medium- and heavy-duty on-highway vehicle and 
work truck fuel efficiency improvement program designed to achieve the 
maximum feasible improvement,'' considering appropriateness, cost-
effectiveness, and technological feasibility. NHTSA does not believe 
that this language precludes the regulation of engines, but rather 
explicitly leaves the regulatory approach to the agency's expertise and 
discretion. See 75 FR at 74173 n. 36. Considering the factors described 
in the NPRM and in Sections III and IV below, NHTSA continues to 
believe that the separate regulation of engines and vehicles is both 
consistent with the agency's statutory mandate to determine how to 
implement a regulatory program designed to achieve the maximum feasible 
improvement and facilitates coordination with EPA's efforts to reduce 
greenhouse gas emissions. The Clean Air act, of course, mandates 
standards for both ``new motor vehicles'' and ``new motor vehicle 
engines'', so there is no issue of authority for separate engine 
standards under the EPA GHG program. CAA section 202(a)(1).
    As described elsewhere in this preamble, the final standards under 
the HD National Program address the complete vehicle, to the extent 
practicable and appropriate under the agencies' respective statutory 
authorities, through complementary engine and vehicle standards. The 
agencies continue to believe that this complementary engine and vehicle 
approach is the best way to achieve near term reductions from the 
heavy-duty sector. However, we also recognize as did the NAS committee 
and a wide range of industry and environmental commenters, that in 
order to fully capture the multi-faceted synergistic aspects of engine 
and vehicle design a more comprehensive complete vehicle standard may 
be appropriate in the future. The agencies are committed to fully 
exploring such a possibility and to developing the testing and modeling 
tools necessary to enable such a regulatory approach. We intend to work 
with all interested stakeholders as we move forward.
(1) Brief Overview of the Heavy-Duty Truck Industry
    The heavy-duty truck sector spans a wide range of vehicles with 
often unique form and function. A primary indicator of the extreme 
diversity among heavy-duty trucks is the range of load-carrying 
capability across the industry. The heavy-duty truck sector is often 
subdivided by vehicle weight classifications, as defined by the 
vehicle's gross vehicle weight rating (GVWR), which is a measure of the 
combined curb (empty) weight and cargo carrying capacity of the 
truck.\23\ Table I-2 below outlines the vehicle weight classifications 
commonly used for many years for a variety of purposes by businesses 
and by several federal agencies, including the Department of 
Transportation, the Environmental Protection Agency, the Department of 
Commerce, and the Internal Revenue Service.
---------------------------------------------------------------------------

    \23\ GVWR describes the maximum load that can be carried by a 
vehicle, including the weight of the vehicle itself. Heavy-duty 
vehicles also have a gross combined weight rating (GCWR), which 
describes the maximum load that the vehicle can haul, including the 
weight of a loaded trailer and the vehicle itself.

                                                        Table I-2--Vehicle Weight Classification
--------------------------------------------------------------------------------------------------------------------------------------------------------
              Class                       2b               3                4                5                6                7                8
--------------------------------------------------------------------------------------------------------------------------------------------------------
GVWR (lb)........................     8,501-10,000    10,001-14,000    14,001-16,000    16,001-19,500    19,501-26,000    26,001-33,000         > 33,001
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In the framework of these vehicle weight classifications, the 
heavy-duty truck sector refers to Class 2b through Class 8 vehicles and 
the engines that power those vehicles.\24\ Unlike light-duty vehicles, 
which are primarily used for transporting passengers for personal 
travel, heavy-duty vehicles fill much more diverse operator needs. 
Heavy-duty pickup trucks and vans (Classes 2b and 3) are used chiefly 
as work truck and vans, and as shuttle vans, as well as for personal 
transportation, with an average annual mileage in the range of 15,000 
miles. The rest of the heavy-duty sector is used for carrying cargo 
and/or performing specialized tasks. ``Vocational'' vehicles, which may 
span Classes 2b through 8, vary widely in size, including smaller and 
larger van trucks, utility ``bucket'' trucks, tank

[[Page 57115]]

trucks, refuse trucks, urban and over-the-road buses, fire trucks, 
flat-bed trucks, and dump trucks, among others. The annual mileage of 
these trucks is as varied as their uses, but for the most part tends to 
fall in between heavy-duty pickups/vans and the large combination 
tractors, typically from 15,000 to 150,000 miles per year, although 
some travel more and some less. Class 7 and 8 combination tractor-
trailers--some equipped with sleeper cabs and some not--are primarily 
used for freight transportation. They are sold as tractors and 
sometimes run without a trailer in between loads, but most of the time 
they run with one or more trailers that can carry up to 50,000 pounds 
or more of payload, consuming significant quantities of fuel and 
producing significant amounts of GHG emissions. The combination 
tractor-trailers used in combination applications can travel more than 
150,000 miles per year.
---------------------------------------------------------------------------

    \24\ Class 2b vehicles designed as passenger vehicles (Medium 
Duty Passenger Vehicles, MDPVs) are covered by the light-duty GHG 
and fuel economy standards and not addressed in this rulemaking.
---------------------------------------------------------------------------

    EPA and NHTSA have designed our respective standards in careful 
consideration of the diversity and complexity of the heavy-duty truck 
industry, as discussed next.
(2) Summary of Final EPA GHG Emission Standards and NHTSA Fuel 
Consumption Standards
    As described above, NHTSA and EPA recognize the importance of 
addressing the entire vehicle in reducing fuel consumption and GHG 
emissions. At the same time, the agencies understand that the 
complexity of the industry means that we will need to use different 
approaches to achieve this goal, depending on the characteristics of 
each general type of truck. We are therefore dividing the industry into 
three discrete regulatory categories for purposes of setting our 
respective standards--combination tractors, heavy-duty pickups and 
vans, and vocational vehicles--based on the relative degree of 
homogeneity among trucks within each category. For each regulatory 
category, the agencies are adopting related but distinct program 
approaches reflecting the specific challenges that we see in these 
segments. In the following paragraphs, we discuss EPA's final GHG 
emission standards and NHTSA's final fuel consumption standards for the 
three regulatory categories of heavy-duty vehicles and their engines.
    The agencies are adopting test metrics that express fuel 
consumption and GHG emissions relative to the most important measures 
of heavy-duty truck utility for each segment, consistent with the 
recommendation of the 2010 NAS Report that metrics should reflect and 
account for the work performed by various types of HD vehicles. This 
approach differs from NHTSA's light-duty program that uses fuel economy 
as the basis. The NAS committee discussed the difference between fuel 
economy (a measure of how far a vehicle will go on a gallon of fuel) 
and fuel consumption (the inverse measure, of how much fuel is consumed 
in driving a given distance) as potential metrics for MD/HD 
regulations. The committee concluded that fuel economy would not be a 
good metric for judging the fuel efficiency of a heavy-duty vehicle, 
and stated that NHTSA should instead consider fuel consumption as the 
metric for its standards. As a result, for heavy-duty pickup trucks and 
vans, EPA and NHTSA are finalizing standards on a per-mile basis (g/
mile for the EPA standards, gallons/100 miles for the NHTSA standards), 
as explained in Section 0 below. For heavy-duty trucks, both 
combination and vocational, the agencies are adopting standards 
expressed in terms of the key measure of freight movement, tons of 
payload miles or, more simply, ton-miles. Hence, for EPA the final 
standards are in the form of the mass of emissions from carrying a ton 
of cargo over a distance of one mile (g/ton-mi). Similarly, the final 
NHTSA standards are in terms of gallons of fuel consumed over a set 
distance (one thousand miles), or gal/1,000 ton-mile. Finally, for 
engines, EPA is adopting standards in the form of grams of emissions 
per unit of work (g/bhp-hr), the same metric used for the heavy-duty 
highway engine standards for criteria pollutants today. Similarly, 
NHTSA is finalizing standards for heavy-duty engines in the form of 
gallons of fuel consumption per 100 units of work (gal/100 bhp-hr).
    Section II below discusses the final EPA and NHTSA standards in 
greater detail.
(a) Class 7 and 8 Combination Tractors
    Class 7 and 8 combination tractors and their engines contribute the 
largest portion of the total GHG emissions and fuel consumption of the 
heavy-duty sector, approximately 65 percent, due to their large 
payloads, their high annual miles traveled, and their major role in 
national freight transport.\25\ These vehicles consist of a cab and 
engine (tractor or combination tractor) and a detachable trailer. In 
general, reducing GHG emissions and fuel consumption for these vehicles 
will involve improvements in aerodynamics and tires and reduction in 
idle operation, as well as engine-based efficiency improvements.
---------------------------------------------------------------------------

    \25\ The on-highway Class 7 and 8 combination tractors 
constitute the vast majority of this regulatory category, and form 
the backbone of this HD National Program. A small fraction of 
combination tractors are used in off-road applications and are 
regulated differently, as described in Section II.
---------------------------------------------------------------------------

    In general, the heavy-duty combination tractor industry consists of 
tractor manufacturers (which manufacture the tractor and purchase and 
install the engine) and trailer manufacturers. These manufacturers are 
usually not the same entity. We are not aware of any manufacturer that 
typically assembles both the finished truck and the trailer and 
introduces the combination into commerce for sale to a buyer. The 
owners of trucks and trailers are often distinct as well. A typical 
truck buyer will purchase only the tractor. The trailers are usually 
purchased and owned by fleets and shippers. This occurs in part because 
trucking fleets on average maintain 3 trailers per tractor and in some 
cases as many as 6 or more trailers per tractor. There are also large 
differences in the kinds of manufacturers involved with producing 
tractors and trailers. For HD highway tractors and their engines, a 
relatively limited number of manufacturers produce the vast majority of 
these products. The trailer manufacturing industry is quite different, 
and includes a large number of companies, many of which are relatively 
small in size and production volume. Setting standards for the products 
involved--tractors and trailers--requires recognition of the large 
differences between these manufacturing industries, which can then 
warrant consideration of different regulatory approaches.
    Based on these industry characteristics, EPA and NHTSA believe that 
the most straightforward regulatory approach for combination tractors 
and trailers is to establish standards for tractors separately from 
trailers. As discussed below in Section IX, the agencies are adopting 
standards for the tractors and their engines in this rulemaking, but 
did not propose and are not adopting standards for trailers.
    As with the other regulatory categories of heavy-duty vehicles, EPA 
and NHTSA have concluded that achieving reductions in GHG emissions and 
fuel consumption from combination tractors requires addressing both the 
cab and the engine, and EPA and NHTSA each are adopting standards that 
reflect this conclusion. The importance of the cab is that its design 
determines the amount of power that the engine must produce in moving 
the truck down the road. As illustrated in Figure I-1, the loads that 
require additional power from the engine include air resistance 
(aerodynamics), tire rolling resistance,

[[Page 57116]]

and parasitic losses (including accessory loads and friction in the 
drivetrain). The importance of the engine design is that it determines 
the basic GHG emissions and fuel consumption performance of the engine 
for the variety of demands placed on the engine, regardless of the 
characteristics of the cab in which it is installed. The agencies 
intend for the final standards to result in the application of improved 
technologies for lower GHG emissions and fuel consumption for both the 
cab and the engine.
---------------------------------------------------------------------------

    \26\ Adapted from Figure 4.1. Class 8 Truck Energy Audit, 
Technology Roadmap for the 21st Century Truck Program: A Government-
Industry Research Partnership, 21CT-001, December 2000.
[GRAPHIC] [TIFF OMITTED] TR15SE11.000

    Accordingly, for Class 7 and 8 combination tractors, the agencies 
are each finalizing two sets of standards. For vehicle-related 
emissions and fuel consumption, tractor manufacturers are required to 
meet vehicle-based standards. Compliance with the vehicle standard will 
typically be determined based on a customized vehicle simulation model, 
called the Greenhouse gas Emissions Model (GEM), which is consistent 
with the NAS Report recommendations to require compliance testing for 
combination tractors using vehicle simulation rather than chassis 
dynamometer testing. This compliance model was developed by EPA 
specifically for this final action. It is an accurate and cost-
effective alternative to measuring emissions and fuel consumption while 
operating the vehicle on a chassis dynamometer. Instead of using a 
chassis dynamometer as an indirect way to evaluate real-world operation 
and performance, various characteristics of the vehicle are measured 
and these measurements are used as inputs to the model. These 
characteristics relate to key technologies appropriate for this 
subcategory of truck--including aerodynamic features, weight 
reductions, tire rolling resistance, the presence of idle-reducing 
technology, and vehicle speed limiters. The model also assumes the use 
of a representative typical engine, rather than a vehicle-specific 
engine, because engines are regulated separately. Using these inputs, 
the model will be used to quantify the overall performance of the 
vehicle in terms of CO2 emissions and fuel consumption. The 
model's development and design, as well as the sources for inputs, are 
discussed in detail in Section II below and in Chapter 4 of the RIA.
(i) Final Standards for Class 7 and 8 Combination Tractors and Their 
Engines
    The vehicle standards that EPA and NHTSA are adopting for Class 7 
and 8 combination tractor manufacturers are based on several key 
attributes related to GHG emissions and fuel consumption that we 
believe reasonably represent the many differences in utility and 
performance among these vehicles. The final standards differ depending 
on GVWR (i.e., whether the truck is Class 7 or Class 8), the height of 
the roof of the cab, and whether it is a ``day cab'' or a ``sleeper 
cab.'' These later two attributes are important because the height of 
the roof, designed to correspond to the height of the trailer, 
significantly affects air resistance, and a sleeper cab generally 
corresponds to the opportunity for extended duration idle emission and 
fuel consumption improvements. We received a number of comments 
supporting this approach and no comments that provided a compelling 
reason to change our approach in this final action.
    Thus, the agencies have created nine subcategories within the Class 
7 and 8 combination tractor category based on the differences in 
expected emissions and fuel consumption associated with the key 
attributes of GVWR, cab type, and roof height. The agencies are setting 
standards beginning in 2014 model year with more stringent standards 
following in 2017 model year. Table I-3 presents the agencies' 
respective standards for combination tractor manufacturers for the 2017 
model year. The standards represent an overall fuel consumption and 
CO2 emissions reduction up to 23 percent from the tractors 
and the engines installed in them when compared to a baseline 2010 
model year tractor and engine without idle shutdown technology. The 
standard values shown below differ somewhat from the proposal, 
reflecting refinements made to the GEM in response to comments. These 
changes did not impact our estimates of the relative effectiveness of 
the various control technologies modeled in this final action nor the 
overall cost or benefits or cost effectiveness estimated for these 
final vehicle standards.
    As proposed, the agencies are exempting certain types of tractors 
which operate off-road to be exempt

[[Page 57117]]

from the combination tractor vehicle standards (although standards 
would still apply to the engines installed in these vehicles). The 
criteria for tractors to be considered off-road have been amended 
slightly from those proposed, in response to public comment. The 
agencies have also recognized, again in response to public comment, 
that some combination tractors operate in a manner essentially the same 
as vocational vehicles and have created a subcategory of ``vocational 
tractors'' as a result. Vocational tractors will be subject to the 
standards for vocational vehicles rather than the combination tractor 
standards. See Section II.B of this preamble.

  Table I-3--Heavy-Duty Combination Tractor EPA Emissions Standards (G CO2/Ton-Mile) and NHTSA Fuel Consumption
                                         Standards (GAL/1,000 Ton-Mile)
----------------------------------------------------------------------------------------------------------------
                                                                        Day cab                   Sleeper cab
                                                        --------------------------------------------------------
                                                              Class 7            Class 8            Class 8
----------------------------------------------------------------------------------------------------------------
                                     2017 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof...............................................              104                 80                 66
Mid Roof...............................................              115                 86                 73
High Roof..............................................              120                 89                 72
----------------------------------------------------------------------------------------------------------------
                               2017 Model Year Gallons of Fuel per 1,000 Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof...............................................               10.2                7.8                6.5
Mid Roof...............................................               11.3                8.4                7.2
High Roof..............................................               11.8                8.7                7.1
----------------------------------------------------------------------------------------------------------------

    In addition, the agencies are finalizing separate performance 
standards for the engines manufactured for use in these trucks. EPA's 
engine-based CO2 standards and NHTSA's engine-based fuel 
consumption standards are implemented using EPA's existing test 
procedures and regulatory structure for criteria pollutant emissions 
from medium- and heavy-duty engines. As at proposal, the final engine 
standards vary depending on engine size linked to intended vehicle 
service class. Consistent with our proposal, the agencies are 
finalizing an interim alternative compression ignition engine standard 
for model years 2014-2016. This alternative standard is designed to 
provide a glide path for legacy diesel engine products that may not be 
able to comply with the final engine standards for model years 2014-16 
given the short (approximately 2-year) lead time of this program. We 
believe this alternative standard is appropriate for a first-ever 
program when the overall baseline performance of the industry is quite 
varied and where the short lead time means that not every product can 
be brought into compliance by 2014. The alternative standard only 
applies through and including model year 2016.
    Separately, EPA is adopting standards for combination tractors that 
apply in use. EPA is also finalizing engine-based N2O and 
CH4 standards for manufacturers of the engines used in these 
combination tractors. EPA is finalizing separate engine-based standards 
for N2O and CH4 because the agency believes that 
emissions of these GHGs are technologically related solely to the 
engine, fuel, and emissions aftertreatment systems, and the agency is 
not aware of any influence of vehicle-based technologies on these 
emissions. NHTSA is not incorporating standards for N2O and 
CH4 because these emissions do not impact fuel consumption 
in a significant way. The standards that EPA is finalizing for 
N2O and CH4 are less stringent than those we 
proposed, reflecting new data provided to EPA in comments on the 
proposal showing that the current baseline level of N2O and 
CH4 emissions varies more than EPA had expected. EPA expects 
that manufacturers of current engine technologies will be able to 
comply with the final N2O and CH4 ``cap'' 
standards with little or no technological improvements; the value of 
the standards will be to prevent significant increases in these 
emissions as alternative technologies are developed and introduced in 
the future. Compliance with the final EPA engine-based CO2 
standards and the final NHTSA engine-based fuel consumption standards, 
as well as the final EPA N2O and CH4 standards, 
will be determined using the appropriate EPA engine test procedure, as 
discussed in Sections II.B, II.D, and II.E below.
    As with the other categories of heavy-duty vehicles, EPA and NHTSA 
are finalizing respective standards that will apply to Class 7 and 8 
tractors at the time of production (as in Table I-3, above). In 
addition, EPA is finalizing separate standards that will apply for a 
specified period of time in use. All of the standards for these 
vehicles, as well as details about the provisions for certification and 
implementation of these standards, are discussed in more detail in 
Sections II, III, IV, and V below and in the RIA.
(ii) EPA's Final Air Conditioning Leakage Standard for Class 7 and 8 
Combination Tractors
    In addition to the final EPA tractor- and engine-based standards 
for CO2 and engine-based standards for N2O, and 
CH4 emissions, EPA is finalizing a separate standard to 
reduce leakage of HFC refrigerant from cabin air conditioning (A/C) 
systems from combination tractors, to apply to the tractor 
manufacturer. This standard is independent of the CO2 
tractor standard, as discussed below in Section II.E.5. Because the 
current refrigerant used widely in all these systems has a very high 
global warming potential, EPA is concerned about leakage of 
refrigerant.\27\
---------------------------------------------------------------------------

    \27\ The global warming potential for HFC-134a refrigerant of 
1430 used in this program is consistent with the Intergovernmental 
Panel on Climate Change Fourth Assessment Report.
---------------------------------------------------------------------------

    Because the interior volume to be cooled for most tractor cabins is 
similar to that of light-duty vehicles, the size and design of current 
tractor A/C systems is also very similar. The compliance approach for 
Class 7 and 8 tractors is therefore similar to that in the light-duty 
rule in that these standards are design-based. Manufacturers will 
choose technologies from a menu of leak-reducing technologies 
sufficient to comply with the standard, as opposed to using a test to 
measure performance.
    However, the final heavy-duty A/C provisions differ in two 
important ways from those established in the light-duty rule. First, 
the light-duty provisions were established as voluntary ways to

[[Page 57118]]

generate credits towards the CO2 g/mi standard, and EPA took 
into account the expected use of such credits in determining the 
stringency of the CO2 emissions standards. In the HD 
National Program, EPA is requiring that manufacturers actually meet a 
standard--as opposed to having the opportunity to earn a credit--for A/
C refrigerant leakage. Thus, refrigerant leakage control is not 
separately accounted for in the final heavy-duty CO2 
standards. We are taking this approach here recognizing that while the 
benefits of leakage control are almost identical between light-duty and 
heavy-duty vehicles on a per vehicle basis, these benefits on a per 
mile basis expressed as a percentage of overall GHG emissions are much 
smaller for heavy-duty vehicles due to their much higher CO2 
emissions rates and higher annual mileage when compared to light-duty 
vehicles. Hence a credit-based approach as done for light-duty vehicles 
would provide less motivation for manufacturers to install low leakage 
systems even though such systems represent a highly cost effective 
means to control GHG emissions. The second difference relates to the 
expression of the leakage rate. The light-duty A/C leakage standard is 
expressed in terms of grams per year. For EPA's heavy-duty program, 
however, because of the wide variety of system designs and 
arrangements, a one-size-fits-all gram per year standard would not be 
appropriate, so EPA is adopting a standard in terms of annual mass 
leakage rate for A/C systems with refrigerant capacities less than or 
equal to 733 grams and percent of total refrigerant leakage per year 
for A/C systems with refrigerant capacities greater than 733 grams. The 
percent of total refrigerant leakage per year requires the total 
refrigerant capacity of the A/C system to be taken into account in 
determining compliance. EPA believes that this approach--a standard 
instead of a credit, and basing the standard on percent or mass of 
leakage over time--is more appropriate for heavy-duty tractors than the 
light-duty vehicle approach and that it will achieve the desired 
reductions in refrigerant leakage. Compliance with the standard will be 
determined through a showing by the tractor manufacturer that its A/C 
system incorporates a combination of low-leak technologies sufficient 
to meet the leakage rate of the applicable standard. The ``menu'' of 
technologies is very similar to that established in the light-duty 
2012-2016 MY vehicle rule.\28\
---------------------------------------------------------------------------

    \28\ EPA has approved an alternative refrigerant, HFO-1234yf, 
which has a very low GWP, for use in light-duty vehicle mobile A/C 
systems. The final heavy-duty vehicle A/C leakage standard is 
designed to account for use of an alternative, low-GWP refrigerant. 
If in the future this refrigerant is approved for heavy-duty 
applications and if it becomes widespread as a substitute for HFC-
134a in heavy-duty vehicle mobile A/C systems, EPA may propose to 
revise or eliminate the leakage standard.
---------------------------------------------------------------------------

    Finally, the agencies did not propose and are not adopting an A/C 
system efficiency standard in this heavy-duty rulemaking, although an 
efficiency credit was a part of the light-duty rule. The much larger 
emissions of CO2 from a heavy-duty tractor as compared to 
those from a light-duty vehicle mean that the relative amount of 
CO2 that could be reduced through A/C efficiency 
improvements is very small.
    A more detailed discussion of A/C related issues is found in 
Section II.E.5 of this preamble.
(b) Heavy-Duty Pickup Trucks and Vans (Class 2b and 3)
    Heavy-duty vehicles with GVWR between 8,501 and 10,000 lb are 
classified in the industry as Class 2b motor vehicles per the Federal 
Motor Carrier Safety Administration definition. As discussed above, 
Class 2b includes MDPVs that are regulated by the agencies under the 
light-duty vehicle rule, and the agencies are not adopting additional 
requirements for MDPVs in this rulemaking. Heavy-duty vehicles with 
GVWR between 10,001 and 14,000 lb are classified as Class 3 motor 
vehicles. Class 2b and Class 3 heavy-duty vehicles (referred to in 
these rules as ``HD pickups and vans'') together emit about 15 percent 
of today's GHG emissions from the heavy-duty vehicle sector.
    About 90 percent of HD pickups and vans are \3/4\-ton and 1-ton 
pickup trucks, 12- and 15-passenger vans, and large work vans that are 
sold by vehicle manufacturers as complete vehicles, with no secondary 
manufacturer making substantial modifications prior to registration and 
use. These vehicle manufacturers are companies with major light-duty 
markets in the United States, primarily Ford, General Motors, and 
Chrysler. Furthermore, the technologies available to reduce fuel 
consumption and GHG emissions from this segment are similar to the 
technologies used on light-duty pickup trucks, including both engine 
efficiency improvements (for gasoline and diesel engines) and vehicle 
efficiency improvements.
    For these reasons, EPA believes it is appropriate to adopt GHG 
standards for HD pickups and vans based on the whole vehicle (including 
the engine), expressed as grams per mile, consistent with the way these 
vehicles are regulated by EPA today for criteria pollutants. NHTSA 
believes it is appropriate to adopt corresponding gallons per 100 mile 
fuel consumption standards that are likewise based on the whole 
vehicle. This complete vehicle approach being adopted by both agencies 
for HD pickups and vans is consistent with the recommendations of the 
NAS Committee in their 2010 Report. EPA and NHTSA also believe that the 
structure and many of the detailed provisions of the recently finalized 
light-duty GHG and fuel economy program, which also involves vehicle-
based standards, are appropriate for the HD pickup and van GHG and fuel 
consumption standards as well, and this is reflected in the standards 
each agency is finalizing, as detailed in Section II.C. These 
commonalities include a new vehicle fleet average standard for each 
manufacturer in each model year and the determination of these fleet 
average standards based on production volume-weighted targets for each 
model, with the targets varying based on a defined vehicle attribute. 
Vehicle testing will be conducted on chassis dynamometers using the 
drive cycles from the EPA Federal Test Procedure (Light-duty FTP or 
``city'' test) and Highway Fuel Economy Test (HFET or ``highway'' 
test).\29\
---------------------------------------------------------------------------

    \29\ The Light-duty FTP is a vehicle driving cycle that was 
originally developed for certifying light-duty vehicles and 
subsequently applied to HD chassis testing for criteria pollutants. 
This contrasts with the Heavy-duty FTP, which refers to the 
transient engine test cycles used for certifying heavy-duty engines 
(with separate cycles specified for diesel and spark-ignition 
engines).
---------------------------------------------------------------------------

    For the light-duty GHG and fuel economy standards, the agencies 
factored in vehicle size by basing the emissions and fuel economy 
targets on vehicle footprint (the wheelbase times the average track 
width).\30\ For those standards, passenger cars and light trucks with 
larger footprints are assigned higher GHG and lower fuel economy target 
levels in acknowledgement of their inherent tendency to consume more 
fuel and emit more GHGs per mile. For HD pickups and vans, the agencies 
believe that setting standards based on vehicle attributes is 
appropriate, but feel that a work-based metric serves as a better 
attribute than the footprint attribute utilized in the light-duty 
vehicle

[[Page 57119]]

rulemaking. Work-based measures such as payload and towing capability 
are key among the parameters that characterize differences in the 
design of these vehicles, as well as differences in how the vehicles 
will be utilized. Buyers consider these utility-based attributes when 
purchasing a heavy-duty pickup or van. EPA and NHTSA are therefore 
finalizing standards for HD pickups and vans based on a ``work factor'' 
attribute that combines their payload and towing capabilities, with an 
added adjustment for 4-wheel drive vehicles. The agencies received a 
number of comments supporting this approach arguing, as the agencies 
had, that this approach was an effective way to encourage technology 
development and to appropriately reflect the utility of work vehicles 
while setting a consistent metric measure of vehicle performance.
---------------------------------------------------------------------------

    \30\ EISA requires CAFE standards for passenger cars and light 
trucks to be attribute-based; See 49 U.S.C. 32902(b)(3)(A).
---------------------------------------------------------------------------

    As proposed, the agencies are adopting provisions such that each 
manufacturer's fleet average standard will be based on production 
volume-weighting of target standards for all vehicles that in turn are 
based on each vehicle's work factor. These target standards are taken 
from a set of curves (mathematical functions), presented in Section 
II.C below and in Sec.  1037.104. EPA is also phasing in the 
CO2 standards gradually starting in the 2014 model year, at 
15-20-40-60-100 percent of the model year 2018 standards stringency 
level in model years 2014-2015-2016-2017-2018, respectively. The phase-
in takes the form of a set of target standard curves, with increasing 
stringency in each model year, as detailed in Section II.C. The final 
EPA standards for 2018 (including a separate standard to control air 
conditioning system leakage) represent an average per-vehicle reduction 
in GHGs of 17 percent for diesel vehicles and 12 percent for gasoline 
vehicles, compared to a common baseline, as described in Sections II.C 
and III.B of this preamble. The rule contains separate standards for 
diesel and gasoline heavy duty pickups and vans for reasons described 
in Section II.C below. EPA is also finalizing a compliance alternative 
whereby manufacturers can phase in different percentages: 15-20-67-67-
67-100 percent of the model year 2019 standards stringency level in 
model years 2014-2015-2016-2017-2018-2019, respectively. This 
compliance alternative parallels and is equivalent to NHTSA's first 
alternative described below.
    NHTSA is allowing manufacturers to select one of two fuel 
consumption standard alternatives for model years 2016 and later. The 
first alternative defines individual gasoline vehicle and diesel 
vehicle fuel consumption target curves that will not change for model 
years 2016-2018, and are equivalent to EPA's 67-67-67-100 percent 
target curves in model years 2016-2017-2018-2019, respectively. The 
target curves for this alternative are presented in Section II.C. The 
second alternative uses target curves that are equivalent to the EPA's 
40-60-100 percent target curves in model years 2016-2017-2018, 
respectively. Stringency for the alternatives has been selected to 
allow a manufacturer, through the use of the credit and deficit carry-
forward provisions that the agencies are also finalizing, to rely on 
the same product plans to satisfy either of these two alternatives, and 
also EPA requirements. If a manufacturer cannot meet an applicable 
standard in a given model year, it may make up its shortfall by 
overcomplying in a subsequent year, called reconciling a credit 
deficit. NHTSA is also allowing manufacturers to voluntarily opt into 
the NHTSA HD pickup and van program in model years 2014 or 2015. For 
these model years, NHTSA's fuel consumption target curves are 
equivalent to EPA's target curves.
    The agencies received a number of comments including from the 
Senate authors and supporters of the Ten-in-Ten Fuel Economy Act 
suggesting that the standards for heavy-duty pickups and vans should be 
made more stringent for gasoline vehicles and that the phase-in timing 
of the standards should be accelerated to the 2016 model year (from 
2018). We also received comments arguing that the proposed standards 
were aggressive and could only be met given the phase-in schedules 
proposed by the agencies. In response to these comments, we reviewed 
again the technology assessments from the 2010 NAS report, our own 
joint light-duty 2012-2016 rulemaking, and information provided by the 
commenters relevant to the stringency of these standards. After 
reviewing all of the information, we continue to conclude that the 
proposed standards and associated phase-in schedules represent 
technically stringent but reasonable standards considering the 
available lead time and costs to bring the necessary technologies to 
market and our own assessments of the efficacy of the technologies when 
applied to heavy-duty pickup trucks and vans. Further detail on the 
feasibility of the standards and the agencies' choices among 
alternative standards is found in Section III.C below.
    The Senate authors and supporters of the Ten-in-Ten Fuel Economy 
Act sent a letter to the agencies encouraging the agencies to finalize 
a fuel economy labeling requirement for heavy-duty pickups and 
vans.\31\ The agencies recognize that consumer information in the form 
of a fuel efficiency label can be a valuable tool to help achieve our 
goals, and we note that the agencies have just recently finalized a new 
fuel economy label for passenger cars and light trucks. See 76 FR at 
39478. That rulemaking effort focused solely on modifying an existing 
label and was a multi-year process with significant public input. As we 
did not propose a consumer label for heavy-duty pickups and vans in 
this action and have not appropriately engaged the public in developing 
such a label, we are not prepared to finalize a consumer-based label in 
this action. However, we do intend to consider this issue as we begin 
work on the next phase of regulations, as we recognize that a consumer 
label can play an important role in reducing fuel consumption and GHG 
emissions.
---------------------------------------------------------------------------

    \31\ See Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    The form and stringency of the EPA and NHTSA standards curves are 
based on a set of vehicle, engine, and transmission technologies 
expected to be used to meet the recently established GHG emissions and 
fuel economy standards for model year 2012-2016 light-duty vehicles, 
with full consideration of how these technologies are likely to perform 
in heavy-duty vehicle testing and use. All of these technologies are 
already in use or have been announced for upcoming model years in some 
light-duty vehicle models, and some are in use in a portion of HD 
pickups and vans as well. The technologies include:
     Advanced 8-speed automatic transmissions.
     Aerodynamic improvements.
     Electro-hydraulic power steering.
     Engine friction reductions.
     Improved accessories.
     Low friction lubricants in powertrain components.
     Lower rolling resistance tires.
     Lightweighting.
     Gasoline direct injection.
     Diesel aftertreatment optimization.
     Air conditioning system leakage reduction (for EPA program 
only).
    See Section III.B for a detailed analysis of these and other 
potential technologies, including their feasibility, costs, and 
effectiveness when employed for reducing fuel consumption and 
CO2 emissions in HD pickups and vans.
    A relatively small number of HD pickups and vans are sold by 
vehicle manufacturers as incomplete vehicles, without the primary load-
carrying

[[Page 57120]]

device or container attached. We are generally regulating these 
vehicles as Class 2b through 8 vocational vehicles but are also 
allowing manufacturers the option to choose to comply with heavy-duty 
pickup or van standards, as described in Section I.C.(2)(c). Although, 
as with vocational vehicles generally, we have little information on 
baseline aerodynamic performance and opportunities for improvement, a 
sizeable subset of these incomplete vehicles, often called cab-chassis 
vehicles, are sold by the vehicle manufacturers in configurations with 
many of the components that affect GHG emissions and fuel consumption 
identical to those on complete pickup truck or van counterparts--
including engines, cabs, frames, transmissions, axles, and wheels. We 
are including provisions that will allow manufacturers to include these 
vehicles, as well as some Class 4 and 5 vehicles, to be regulated under 
the chassis-based HD pickup and van program (i.e. subject to the 
standards for HD pickups and vans), rather than the vocational vehicle 
program. These provisions are described in Section V.B(1)(e).
    In addition to the EPA CO2 emission standards and the 
NHTSA fuel consumption standards for HD pickups and vans, EPA is also 
finalizing standards for two additional GHGs, N2O and 
CH4, as well as standards for air conditioning-related HFC 
emissions. These standards are discussed in more detail in Section 
II.E. Finally, EPA is finalizing standards that will apply to HD 
pickups and vans in use. All of the standards for these HD pickups and 
vans, as well as details about the provisions for certification and 
implementation of these standards, are discussed in Section II.C.
(c) Class 2b-8 Vocational Vehicles
    Class 2b-8 vocational vehicles consist of a wide variety of vehicle 
types. Some of the primary applications for vehicles in this segment 
include delivery, refuse, utility, dump, and cement trucks; transit, 
shuttle, and school buses; emergency vehicles, motor homes,\32\ tow 
trucks, among others. These vehicles and their engines contribute 
approximately 20 percent of today's heavy-duty truck sector GHG 
emissions.
---------------------------------------------------------------------------

    \32\ NHTSA's final fuel consumption standards will not apply to 
recreational vehicles, as discussed in earlier in this preamble 
section.
---------------------------------------------------------------------------

    Manufacturing of vehicles in this segment of the industry is 
organized in a more complex way than that of the other heavy-duty 
categories. Class 2b-8 vocational vehicles are often built as a chassis 
with an installed engine and an installed transmission. Both the engine 
and transmissions are typically manufactured by other manufacturers and 
the chassis manufacturer purchases and installs them. Many of the same 
companies that build Class 7 and 8 tractors are also in the Class 2b-8 
chassis manufacturing market. The chassis is typically then sent to a 
body manufacturer, which completes the vehicle by installing the 
appropriate feature--such as dump bed, delivery box, or utility 
bucket--onto the chassis. Vehicle body manufacturers tend to be small 
businesses that specialize in specific types of bodies or specialized 
features.
    EPA and NHTSA proposed that in this vocational vehicle category the 
proposed GHG and fuel consumption standards apply to chassis 
manufacturers. Chassis manufacturers play a central role in the 
manufacturing process. The product they produce--the chassis with 
engine and transmission--includes the primary technologies that affect 
GHG emissions and fuel consumption. They also constitute a much more 
limited group of manufacturers for purposes of developing and 
implementing a regulatory program. The agencies believe that a focus on 
the body manufacturers would be much less practical, since they 
represent a much more diverse set of manufacturers, many of whom are 
small businesses. Further, the part of the vehicle that they add 
affords very few opportunities to reduce GHG emissions and fuel 
consumption (given the limited role that aerodynamics plays in many 
types of lower speed and stop-and-go operation typically found with 
vocational vehicles.) Therefore, the agencies proposed that the 
standards in this vocational vehicle category would apply to the 
chassis manufacturers of all heavy-duty vehicles not otherwise covered 
by the HD pickup and van standards or Class 7 and 8 combination tractor 
standards discussed above. The agencies requested comment on the 
proposed focus on chassis manufacturers.
    Volvo and Daimler commented that the EISA does not speak to the 
regulation of subsystems, such as engines or incomplete vehicles, and 
argued that on the other hand, Section 32902(k)(2) prescribes the 
regulation of vehicles. Volvo further stated that precedent for the 
regulation of complete vehicles exists in the light-duty fuel economy 
rule. As noted above, NHTSA does not believe that EISA mandates a 
particular regulatory approach, but rather gives the agency wide 
latitude and explicitly leaves that determination to the agency. NHTSA 
also notes that its heavy-duty rule creates a new fuel efficiency 
program for which the light-duty program does not necessarily serve as 
a useful precedent for considerations of its structure. Unlike the 
light-duty fuel economy program, MD/HD vehicles are produced in widely 
diverse stages. Further, given the MD/HD market structure, where the 
complete vehicle manufacturers are numerous, diverse, and often small 
businesses, the regulation of complete vehicles would create unique 
difficulties for the application of appropriate and feasible 
technologies. These same considerations justify EPA's determination, 
pursuant to CAA section 202 (a), to regulate only chassis manufacturers 
in this first stage of GHG rules for the heavy-duty sector. NHTSA also 
notes that this rule does not represent the first time that the agency 
has regulated incomplete vehicles. Rather, incomplete vehicles have a 
history of regulation under the Federal Motor Vehicle Safety 
Standards.\33\ For this first phase of the HD National Program, NHTSA 
and EPA believe that given the complexity of the manufacturing process 
for vocational vehicles, and given the wide range of entities that 
participate in that process, vehicle fuel consumption standards would 
be most appropriately applied to chassis manufacturers and not to body 
builders.
---------------------------------------------------------------------------

    \33\ See 49 U.S.C. 567.5 and 568.4.
---------------------------------------------------------------------------

    The agencies continue to believe that regulation of the chassis 
manufacturers for this vocational vehicle category will achieve the 
maximum feasible improvement in fuel efficiency for purposes of EISA 
and appropriate emissions reductions for purposes of the CAA. 
Therefore, consistent with our proposal the final standards in this 
vocational vehicle category apply to the chassis manufacturers of all 
heavy-duty vehicles not otherwise covered by the HD pickup and van 
standards or Class 7 and 8 combination tractor standards discussed 
above. As discussed above, EPA and NHTSA have concluded that reductions 
in GHG emissions and fuel consumption require addressing both the 
vehicle and the engine. As discussed above for Class 7 and 8 
combination tractors, the agencies are each finalizing two sets of 
standards for Class 2b-8 vocational vehicles. For vehicle-related 
emissions and fuel consumption, the agencies are adopting standards for 
chassis manufacturers: EPA CO2 (g/ton-mile) standards and 
NHTSA fuel consumption (gal/1,000 ton-mile) standards). While the 
agencies believe that a freight-based metric is broadly appropriate for 
vocational vehicles

[[Page 57121]]

because the vocational vehicle population is dominated by freight 
trucks and maintain that it is appropriate for the first phase of the 
program, the agencies may consider other metrics for future phases of a 
HD program. Manufacturers will use GEM, the same customized vehicle 
simulation model used for Class 7 and 8 tractors, to determine 
compliance with the vocational vehicle standards finalized in this 
action. The primary manufacturer-generated input into the GEM for this 
category of trucks will be a measure of tire rolling resistance, as 
discussed further below, because tire improvements are the primary 
means of vehicle improvement available at this time for vocational 
vehicles. The model also assumes the use of a typical representative, 
compliant engine in the simulation, resulting in an overall value for 
CO2 emissions and one for fuel consumption. This is done for 
the same reason as for combination tractors. As is the case for 
combination tractors, the manufacturers of the engines intended for 
vocational vehicles will be subject to separate engine-based standards.
(i) Final Standards for Class 2b-8 Vocational Vehicles and Their 
Engines
    Based on our analysis and research, the agencies believe that the 
primary opportunity for reductions in vocational vehicle GHG emissions 
and fuel consumption will be through improved engine technologies and 
improved tire rolling resistance. For engines, EPA and NHTSA are 
adopting separate standards for the manufacturers of engines used in 
Class 2b-8 vocational vehicles (the same approach as for combination 
tractors and engines intended for use in those tractors). EPA's final 
engine-based CO2 standards and NHTSA's final engine-based 
fuel consumption standards vary based on the expected weight class and 
usage of the truck into which the engine will be installed. Tire 
rolling resistance is closely related to the weight of the vehicle. 
Therefore, we are adopting vehicle-based standards for these trucks 
which vary according to one key attribute, GVWR. For this initial HD 
rulemaking, we are adopting standards based on the same groupings of 
truck weight classes used for the engine standards--light heavy-duty, 
medium heavy-duty, and heavy heavy-duty. These groupings are 
appropriate for the final vehicle-based standards because they parallel 
the general divisions among key engine characteristics, as discussed in 
Section II.
    The agencies are also finalizing an interim alternative compression 
ignition (diesel) engine standard for model years 2014-2016, again 
analogous to the alternative standards for compression ignition engines 
use in combination tractors. The need for this provision and our 
considerations in adopting it are the same for the engines used in 
vocational vehicles as for the engines used in combination tractors. As 
we proposed, these alternative standards will only be available through 
model year 2016. In addition, manufacturers that use the interim 
alternative diesel engine standards for model years 2014-2016 under the 
EPA program must use equivalent fuel consumption standards under the 
NHTSA program.
    For the 2014 to 2016 model years, manufacturers may also choose to 
meet alternative engine standards that are phased-in over the model 
years to coincide with new EPA On-Board Diagnostic (OBD) requirements 
applicable for these same model years. See Sections II.B and II.D 
below.
    The agencies received a significant number of comments including 
from the Senate authors and supporters of the Ten-in-Ten Fuel Economy 
Act arguing that our proposed standards for vocational vehicles did not 
reflect all of the technologies identified in the 2010 NAS report. The 
commenters encouraged the agencies to expand the program to bring in 
additional reductions through the use of new transmission technologies, 
vehicle weight reductions and hybrid drivetrains. In general, the 
agencies agree with the commenters' central contention that there are 
additional technologies to improve the fuel efficiency of vocational 
vehicles. As discussed later, we are finalizing provisions to allow new 
technologies to be brought into the program through the innovative 
technology credit program. More specifically, we are including 
provisions to account for and credit the use of hybrid technology as a 
technology that can reduce emissions and fuel consumption. Hybrid 
technology can currently be a cost-effective technology in certain 
specific vocational applications, and the agencies want to recognize 
and promote the use of this technology. (See Sections I.E and IV 
below.) However, we are not finalizing standards that are premised on 
the use of these additional technologies because we have not been able 
to develop the test procedures, regulatory mechanisms and baseline 
performance data necessary to adopt a more comprehensive approach to 
controlling fuel efficiency and GHG emissions from vocational vehicles. 
In concept, the agencies would need to know the baseline weight, 
aerodynamic performance, and transmission configuration for the wide 
range of vocational vehicles produced today. We do not have this 
information even for relatively small portions of this market (e.g. 
concrete mixers) nor are we well informed regarding the potential 
tradeoffs to changes to vehicle utility that might exist for changes to 
concrete mixer designs in response to a regulation. Nor did the 
commenters provide any such information. Absent this information and 
the necessary regulatory tools, we believe the standards we are 
finalizing for vocational vehicles represent the most appropriate 
standards for this segment during the model years of the first phase of 
the program. We intend to address fuel consumption and GHG emissions 
from these vehicles in a more comprehensive manner through future 
regulation and look forward to working with all stakeholders on this 
important segment in the future.
    The agencies are setting standards beginning in the 2014 model year 
and establishing more stringent standards in the 2017 model year. Table 
I-4 presents EPA's final CO2 standards and NHTSA's final 
fuel consumption standards for chassis manufacturers of Class 2b 
through Class 8 vocational vehicles for the 2017 model year. The 2017 
model year standards represent a 6 to 9 percent reduction in 
CO2 emissions and fuel consumption over a 2010 model year 
vehicle.

   Table I-4--Final 2017 Class 2b-8 Vocational Vehicle EPA CO2 Standards and NHTSA Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
                                                          Light heavy-duty  Medium heavy-duty   Heavy heavy-duty
                                                             Class 2b-5         Class 6-7           Class 8
----------------------------------------------------------------------------------------------------------------
                           EPA CO2 (gram/ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
CO2 Emissions..........................................              373                225                222
----------------------------------------------------------------------------------------------------------------

[[Page 57122]]

 
              NHTSA Fuel Consumption (gallon per 1,000 ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
Fuel Consumption.......................................               36.7               22.1               21.8
----------------------------------------------------------------------------------------------------------------

     As mentioned above for Class 7 and 8 combination tractors, EPA 
believes that N2O and CH4 emissions are 
technologically related solely to the engine, fuel, and emissions 
aftertreatment systems, and the agency is not aware of any influence of 
vehicle-based technologies on these emissions. Therefore, for Class 2b-
8 vocational vehicles, EPA's final N2O and CH4 
standards cover manufacturers of the engines to be used in vocational 
vehicles. EPA did not propose, nor are we adopting separate vehicle-
based standards for these GHGs. As for the engines used in Class 7 and 
8 tractors, we are finalizing a somewhat higher N2O and 
CH4 emission standards reflecting new data submitted to the 
agencies during the public comment period. EPA expects that 
manufacturers of current engine technologies will be able to comply 
with the final ``cap'' standards with little or no technological 
improvements; the value of the standards is that they will prevent 
significant increases in these emissions as alternative technologies 
are developed and introduced in the future. Compliance with the final 
EPA engine-based CO2 standards and the final NHTSA fuel 
consumption standards, as well as the final EPA N2O and 
CH4 standards, will be determined using the appropriate EPA 
engine test procedure, as discussed in Section II below.
    As with the other regulatory categories of heavy-duty vehicles, EPA 
and NHTSA are adopting standards that apply to Class 2b-8 vocational 
vehicles at the time of production, and EPA is adopting standards for a 
specified period of time in use. All of the standards for these trucks, 
as well as details about the final provisions for certification and 
implementation of these standards, are discussed in more detail later 
in this notice and in the RIA.
    EPA did not propose, nor is it adopting A/C refrigerant leakage 
standards for Class 2b-8 vocational vehicles, primarily because of the 
number of entities involved in their manufacture and thus the potential 
for different entities besides the chassis manufacturer to be involved 
in the A/C system production and installation.
(d) What manufacturers are not covered by the final standards?
    The NPRM proposed to defer temporarily greenhouse gas emissions and 
fuel consumption standards for any manufacturers of heavy-duty engines, 
manufacturers of combination tractors, and chassis manufacturers for 
vocational vehicles that meet the ``small business'' size criteria set 
by the Small Business Administration (SBA). 13 CFR 121.201 defines a 
small business by the maximum number of employees; for example, this is 
currently 1,000 for heavy-duty vehicle manufacturing and 750 for engine 
manufacturing.\34\ The agencies stated that they would instead consider 
appropriate GHG and fuel consumption standards for these entities as 
part of a future regulatory action. This includes both U.S.-based and 
foreign small-volume heavy-duty manufacturers. To ensure that the 
agencies are aware of which companies would be exempt, the agencies 
proposed to require that such entities submit a declaration describing 
how it qualifies as a small entity under the provisions of 13 CFR 
121.201 to EPA and NHTSA as prescribed in Section V below.
---------------------------------------------------------------------------

    \34\ See Sec.  1036.150 and Sec.  1037.150
---------------------------------------------------------------------------

    EPA and NHTSA were not aware of any manufacturers of HD pickups and 
vans that meet these criteria. For each of the other categories and for 
engines, the agencies identified a small number of manufacturers that 
would appear to qualify as small businesses under the SBA size 
criterion, which were estimated to comprise a negligible percentage of 
the U.S. market.\35\ Therefore, the agencies believed that deferring 
the standards for these companies at this time would have a negligible 
impact on the GHG emission reductions and fuel consumption reductions 
that the program would otherwise achieve. The agencies proposed to 
consider appropriate GHG emissions and fuel consumption standards for 
these entities as part of a future regulatory action.
---------------------------------------------------------------------------

    \35\ Two heavy-duty combination tractor and ten chassis 
manufacturers each comprising less than 0.5 percent of the total 
tractor and vocational market based on Polk Registration Data from 
2003 through 2007, and three engine manufacturing entities based on 
company information included in Hoover's, comprising less than 0.1 
percent of the total heavy-duty engine sales in the United States 
based on 2009 and 2010 EPA certification information.
---------------------------------------------------------------------------

    The Institute for Policy Integrity (IPI) commented that the small 
business exemption proposed in the NPRM was based on the improper 
framework of whether the exemption would have a negligible impact, and 
did not adequately explain why the regulation of small businesses would 
face special compliance and administrative burdens. IPI argued that the 
only proper basis for this exemption would be if the agencies could 
explain how these burdens create costs that exceeded the benefits of 
regulation.
    NHTSA believes that developing standards that are ``appropriate, 
cost-effective, and technologically feasible'' under 49 U.S.C. 
32902(k)(2) includes the authority to exclude certain manufacturers if 
their inclusion would work against these statutory factors. Similarly, 
under section 202(a) of the CAA, EPA may reasonably choose to defer 
regulation of industry segments based on considerations of cost, cost-
effectiveness and available lead time for standards. As noted above, 
small businesses make up a very small percentage of the market and are 
estimated to have a negligible impact on the emissions and fuel 
consumption goals of this program. The short lead time before the 
CO2 standards take effect, the extremely small fuel savings 
and emissions contribution of these entities, and the potential need to 
develop a program that would be structured differently for them (which 
would require more time to determine and adopt), all led to the 
decision that the inclusion of small businesses would not be 
appropriate at this time. Therefore, the final rule exempts small 
businesses as proposed.
    Volvo and EMA stated that by exempting small businesses based on 
the definition from SBA, the rules would create a competitive advantage 
for small businesses over larger entities. EMA commented that the 
exemption should not apply to market segments where a small business 
has a significant share of a particular HD market. Volvo argued that 
the exempted businesses could expand their product offerings or

[[Page 57123]]

sell vehicles on behalf of larger entities, thereby inappropriately 
increasing the scope of the exclusion. The agencies anticipate that the 
gain a manufacturer might achieve by restructuring its practices and 
products to circumvent the standard (which for vocational vehicles 
simply means installing low rolling resistance tires) in the first few 
years of this program will be outweighed by the costs, particularly as 
small businesses anticipate their potential inclusion in the next 
rulemaking.
    Volvo also commented that the agencies should elaborate on the 
requirements for the exemption in greater detail. The agencies agree 
that this may help to clarify the process. As suggested by Volvo, the 
agencies will consider affiliations to other companies and evidence of 
spin-offs for the purpose of circumventing the standards in determining 
whether a business qualifies as a small entity for this exclusion. Each 
declaration must be submitted in writing to EPA and NHTSA as prescribed 
in Section V below. As the agencies gain more experience with this 
exemption, these clarifications may be codified in the regulatory text 
of a future rulemaking.
    Volvo further commented that the agencies were adopting an 
exemption of ``small businesses'' in order to avoid doing a Small 
Business Regulatory Enforcement Fairness Act (SBREFA) and Regulatory 
Flexibility Act (RFA) analysis. The agencies would like to reiterate 
that they have decided not to include small businesses at this time due 
to the factors described above. The discussion on an RFA analysis is 
laid out in Section XII(4).
    The agencies continue to believe that deferring the standards for 
these companies at this time will have a negligible impact on the GHG 
emission reductions and fuel consumption reductions that the program 
would otherwise achieve. Therefore, the final rules include the small 
business exemption as proposed. The specific deferral provisions are 
discussed in more detail in Section II.
    The agencies will consider appropriate GHG emissions and fuel 
consumption standards for these entities as part of a future regulatory 
action.
(e) Light-Duty Vehicle CH4 and N2O Standards 
Flexibility
    After finalization of the N2O and CH4 
standards for light-duty vehicles as part of the 2012-2016 MY program, 
some manufacturers raised concerns that they may have difficulty 
meeting those standards across their light-duty vehicle fleets. In 
response to these concerns, as part of the same Federal Register notice 
as the heavy-duty proposal, EPA requested comments on additional 
options for manufacturers to comply with light-duty vehicle 
N2O and CH4 standards to provide additional near-
term flexibility. Commenters providing comment on this issue supported 
additional flexibility for manufacturers. EPA is finalizing provisions 
allowing manufacturers to use CO2 credits, on a 
CO2-equivalent basis, to meet the N2O and 
CH4 standards, which is consistent with many commenters' 
preferred approach. Manufacturers will have the option of using 
CO2 credits to meet N2O and CH4 
standards on a test group basis as needed for MYs 2012-2016.
(f) Alternative Fuel Engines and Vehicles
    The agencies believe that it is also appropriate to take steps to 
recognize the benefits of flexible-fueled vehicles (FFVs) and dedicated 
alternative-fueled vehicles. In the NPRM, EPA proposed to determine the 
emissions performance of dedicated alternative fuel engines and pickup 
trucks and vans by measuring tailpipe CO2 emissions. NHTSA 
proposed to determine fuel consumption performance of non-electric 
dedicated alternative fuel engines and pickup trucks and vans by 
measuring fuel consumption with the alternative fuel and then 
calculating a petroleum equivalent fuel consumption using a Petroleum 
Equivalency Factor (PEF) that is determined by the Department of 
Energy. NHTSA proposed to treat electric vehicles as having zero fuel 
consumption, comparable to the EPA proposal. Both agencies proposed to 
determine FFV performance in the same way as for GHG emissions for 
light-duty vehicles, with a 50-50 weighting of alternative and 
conventional fuel test results through MY 2015, and a weighting based 
on demonstrated fuel use in the real world after MY 2015 (defaulting to 
an assumption of 100 percent conventional fuel use). This approach was 
considered to be a reasonable and logical way to properly credit 
alternative fuel use in FFVs in the real world without imposing a 
difficult burden of proof on manufacturers. However, unlike in the 
light-duty rule, the agencies do not believe it is appropriate to 
create a provision for additional incentives similar to the 2012-2015 
light-duty incentive program (See 49 U.S.C. 32904) because the HD 
sector does not have the incentives mandated in EISA for light-duty 
FFVs, and so has not relied on the existence of such credits in 
devising compliance strategies for the early model years of this 
program. See 74 FR at 49531. In fact, manufacturers have not in the 
past produced FFV heavy-duty vehicles. On the other hand, the agencies 
sought comment on how to properly recognize the impact of the use of 
alternative fuels, and E85 in particular, in HD pickups and vans, 
including the proper accounting for alternative fuel use in FFVs in the 
real world.\36\ See 75 FR at 74198.
---------------------------------------------------------------------------

    \36\ E85 is a blended fuel consisting of nominally 15 percent 
gasoline and 85 percent ethanol.
---------------------------------------------------------------------------

    The agencies received several comments from natural gas vehicle 
(NGV) interests arguing for greater crediting of NGVs than the proposed 
approach would have provided. Clean Energy, Hayday Farms, Border 
Valley, AGA, Ryder, Encana, and a group of NGV interests commented that 
the NPRM ignored Congress' intent to incentivize the use of NGVs by not 
including the conversion factor that exists in the light-duty statutory 
language. The commenters argued that Congress' intent to incentivize 
NGVs is evident in the formula contained in 49 U.S.C. 32905, which 
deems a gallon equivalent of gaseous fuel to have a fuel content of 
0.15 gallon of fuel. The commenters also argued that Congress 
implicitly intended NGVs to be incentivized in this rulemaking, as 
evidenced by the incentives in the light-duty statutory text. AGA and 
Hayday suggested that the agencies were not including the NGV incentive 
from light-duty because Congress did not explicitly include it in 49 
U.S.C. 32902(k), and argued that this would contradict the agencies' 
inclusion of other incentives similar to the light-duty rule.
    The American Trucking Association expressed support for estimating 
natural gas fuel efficiency by using carbon emissions from natural gas 
rather than energy content to estimate fuel consumption. ATA explained 
that two vehicles can achieve the same fuel efficiency, yet one 
operated on natural gas would have a lower carbon dioxide emissions 
rate. A natural gas conversion factor that uses carbon content versus 
energy content is a more appropriate method for calculating fuel 
consumption, in the commenter's view. A number of other groups 
commented on the appropriate method to use in establishing fuel 
consumption from alternative fueled vehicles. A group of NGV interests, 
Ryder, Border Valley Trading, Waste Management, Robert Bosch and the 
Blue Green Alliance encouraged the agencies to adopt the 0.15 
conversion factor in estimating fuel consumption for FFVs and 
alternative fuel vehicles finalized in the light-duty

[[Page 57124]]

2012-2016 MY vehicle standards. The suggested incentive would 
effectively reduce the calculated fuel consumption for FFVs and 
alternative fuel vehicles by a factor of 85 percent. The commenters 
argued that the incentive is needed for heavy-duty vehicles to 
encourage the use of natural gas and to reduce the nation's dependence 
on petroleum.
    The agencies reassessed the options for evaluating the 
CO2 and fuel consumption performance of alternative fuel 
vehicles in response to comments and because the agencies recognized 
that the treatment of alternate fuel vehicles was one of the few 
provisions in the proposal where the EPA and NHTSA programs were not 
aligned. The agencies conducted an analysis comparing fuel consumption 
calculated based on CO2 emissions \37\ to fuel consumption 
calculated based on gasoline or diesel energy equivalency to evaluate 
impacts of a consistent consumption measurement for all vehicle classes 
covered by this program and to further understand how alternative fuels 
would be impacted by this measurement methodology. In particular the 
agencies evaluated how measuring consumption via CO2 
emissions would hinder or benefit the application of alternative fuels 
versus following similar alternative fuel incentivizing programs 
provided via statute for the Agency's light-duty programs. The analysis 
showed measuring a vehicle's CO2 output converted to fuel 
consumption provided a fuel consumption measurement benefit to those 
vehicles operating on fuels other than gasoline or diesel. For CNG, LNG 
and LPG the benefit is approximately 19 percent to 24 percent, for 
biodiesel and ethanol blends the benefit is approximately 1 percent to 
3 percent, and for electricity and hydrogen fuels the benefit is 100 
percent benefit, as fuel consumption is zero. The agencies also 
considered that the EPA Renewable Fuel Standard,\38\ a separate 
program, requires an increase in the volume of renewable fuels used in 
the U.S. transportation sector. For the fuels covered by the Renewable 
Fuels Standard additional incentives are not needed in this regulation 
given the large volume increases required under the Renewable Fuel 
Standard.
---------------------------------------------------------------------------

    \37\ Fuel consumption calculated from measured CO2 
using conversion factors of 8,887 g CO2/gallon for 
gasoline (for alternative fuel engines that are derived from 
gasoline engines), and 10,180 g CO2/gallon for diesel 
fuel (for alternative fuel engines that are derived from diesel 
engines).
    \38\ EPA is responsible for developing and implementing 
regulations to ensure that transportation fuel sold in the United 
States contains a minimum volume of renewable fuel. The RFS program 
was created under the Energy Policy Act (EPAct) of 2005, and 
expanded under the Energy Independence and Security Act (EISA) of 
2007.
---------------------------------------------------------------------------

    The agencies continue to believe that alternative-fueled vehicles, 
including NGVs, provide fuel consumption benefits that should be, and 
are, accounted for in this program. However, the agencies do not agree 
with the commenters' claim that the NGV incentive contained in EISA, 
and reflected in the light-duty program, is an explicit Congressional 
directive that must also be applied to the heavy-duty program, nor that 
the light-duty incentive for NGVs should be interpreted as an implicit 
Congressional directive for NGVs to be comparably incentivized in the 
heavy-duty program. Further, the agencies believe that the fuel 
consumption benefits that alternative fuel vehicles would obtain 
through measuring CO2 emissions for the EPA program and 
converting CO2 emissions to fuel consumption for the NHTSA 
program accurately reflects their energy benefits. This accurate 
accounting, in conjunction with the volumetric increases required by 
the Renewable Fuels Standard, provides sufficient incentives for these 
vehicles. The agencies continue to believe that the light-duty 
conversion factor is not appropriate for this program. Instead, the 
agencies are finalizing measuring the performance of alternative fueled 
vehicles by measuring CO2 emissions for the EPA program and 
converting CO2 emissions to fuel consumption for the NHTSA 
program. The agencies are also finalizing measuring FFV performance 
with a 50-50 weighting of alternative and conventional fuel test 
results through MY 2015, and an agency- or manufacturer-determined 
weighting based on demonstrated fuel use in the real world after MY 
2015 (defaulting to an assumption of 100 percent conventional fuel 
use).
    The agencies believe this structure accurately reflects the fuel 
consumption of the vehicles while at the same time providing an 
incentive for the alternative fuel use. (For example, natural gas heavy 
duty engines perform 20 to 30 percent better than their diesel and 
gasoline counterparts from a CO2 perspective, and so meet 
the standards adopted in these rules without cost, and indeed will be 
credit generators without cost.) We believe this is a substantial 
enough advantage to spur the market for these vehicles. The calculation 
at the same time does not overestimate the benefit from these 
technologies, which could reduce the effectiveness of the regulation. 
Therefore, the final rules do not include the light-duty 0.15 
conversion factor for NGVs. The agencies would like to clarify that the 
decision not to include an NGV incentive was based on this policy 
determination, not on a belief that incentives present in the light-
duty rule could not be developed for the heavy-duty sector because they 
were not explicitly included in Section 32902(k).
    NHTSA recognizes that EPCA/EISA promotes incentives for alternative 
fueled vehicles for different purposes than does the CAA, and that 
there may be additional energy and national security benefits that 
could be achieved through increasing fleet percentages of natural gas 
and other alternative-fueled vehicles. More alternative-fueled vehicles 
on road would arguably displace petroleum-fueled vehicles, and thereby 
increase both U.S. energy and national security by reducing the 
nation's dependence on foreign oil.
    However, a rule that adopts identical incentive provisions reduces 
industry reporting burdens and NHTSA's monitoring burden. In addition, 
the agencies are concerned that providing greater incentives under 
EPCA/EISA might lead to little increased production of alternative 
fueled vehicles. If this were the case, then the benefits of 
harmonization could outweigh any potential gains from providing greater 
incentives. It is also consistent with Executive Order 13563.\39\
---------------------------------------------------------------------------

    \39\ EO 13563 states that an agency shall ``tailor its 
regulations to impose the least burden on society, consistent with 
obtaining regulatory objectives, taking into account, among other 
things, and to the extent practicable, the costs of cumulative 
regulations,'' and ``promote such coordination, simplification, and 
harmonization'' as will reduce redundancy, inconsistency, and costs 
of multiple regulatory requirements.
---------------------------------------------------------------------------

    Adopting the same incentive provisions could also have benefits for 
the public, the regulated industries, and the agencies. This approach 
allows manufacturers to project clear benefits for the application of 
GHG-reduction and fuel efficiency technologies, thus spurring their 
adoption.
    This combined rulemaking by EPA and NHTSA is designed to regulate 
two separate characteristics of heavy duty vehicles: Greenhouse gas 
emissions (GHG) and fuel consumption. In the case of diesel or gasoline 
powered vehicles, there is a one-to-one relationship between these two 
characteristics. Each gallon of gasoline combusted by a truck engine 
generates approximately 8,887 grams of CO2; and each gallon 
of diesel fuel burned generates about 10,180 grams of CO2. 
Because no available technologies reduce tailpipe CO2 
emissions per gallon of fuel combusted, any rule that limits tailpipe 
CO2 emissions is

[[Page 57125]]

effectively identical to a rule that limits fuel consumption. 
Compliance by a truck manufacturer with the NHTSA fuel economy rule 
assures compliance with the EPA rule, and vice versa.
    For alternatively fueled vehicles, which use no petroleum, the 
situation is different. For example, a natural gas vehicle that 
achieves approximately the same fuel economy as a diesel powered 
vehicle would emit 20 percent less CO2; and a natural gas 
vehicle with the same fuel economy as a gasoline vehicle would emit 30 
percent less CO2. Yet natural gas vehicles consume no 
petroleum. To the extent that the goal of the NHTSA fuel economy 
portion of this rulemaking is to curb petroleum use, crediting natural 
gas vehicles with zero fuel consumption per mile could contribute to 
achieving that goal. Similar differences between oil consumption and 
greenhouse gas emissions would apply to electric vehicles, hybrid 
electric vehicles, and biofuel-powered vehicles.
    NHTSA notes that the purpose of EPCA/EISA is not merely to curb 
petroleum use--it is more generally to secure energy independence, 
which can be achieved by reducing petroleum use. The value of 
incentivizing natural gas, electric vehicles, biofuels, hydrogen, or 
other alt fuel vehicles for energy independence is limited to the 
extent that the alternative fuels may be imported.
    In the recent rulemaking for light-duty vehicles, EPA and NHTSA 
have followed the light duty specific statutory provision that treats 
one gallon of alternative fuel as equivalent to 0.15 gallons of 
gasoline until MY 2016, when performance on the EPA CO2 
standards is measured based on actual emissions. 75 FR at 25433. 
Following that MY 2012-2015 approach in this heavy duty program would 
mean that, for example, a natural gas powered truck would have 
attributed to it 20 percent less CO2 emissions than a 
comparable diesel powered truck, but 85 percent less fuel consumption. 
Engine manufacturers with a relatively large share of alternative-fuel 
products would likely have an easier time complying with NHTSA's 
average fuel economy standard than with EPA's GHG standard. Similarly, 
engine manufacturers with a relatively small share of alternative-fuel 
products would have a relatively easier time complying with EPA's 
CO2 standard than with NHTSA's fuel economy standard. In 
that way, the rule would not differ from the light duty vehicle rules.
    Instead, in this program, EPA and NHTSA are establishing identical 
rules. Fuel consumption for alternatively-powered vehicles will be 
calculated according to their tailpipe CO2 emissions. In 
that way, there will be a one-to-one relationship between fuel economy 
and tailpipe CO2 emissions for all vehicles. However, this 
might not result in a one-to-one relationship between petroleum 
consumption and GHG emissions for all vehicles. On the other hand, it 
could have the disadvantage of not doing more to encourage some cost-
effective means of reducing petroleum consumption by trucks, and the 
accompanying energy security costs. By attributing to natural gas 
engines only 20 percent less fuel consumption than comparable diesel 
engines, because they emit 20 percent less CO2, rather than 
attributing to them a much larger percentage reduction in fuel 
consumption, because they use no petroleum, this uniform approach to 
rulemaking provides less of an incentive for technologies that reduce 
consumption of petroleum-based fuels.
    In the future, the Agencies will consider the possibility of 
proposing standards in a way that more fully reflects differences in 
fuel consumption and greenhouse gas emissions. Under such standards, 
any given vehicle might ``over-comply'' with the fuel economy standard, 
but might ``under-comply'' with the greenhouse gas standard. Therefore, 
in meeting the fleet-wide requirements, a manufacturer would need to 
meet both standards using all available options, such as credit trading 
and technology mix. Allowing for two distinct standards might enable 
manufacturers to achieve the twin goals of reducing greenhouse gas 
emissions and decreasing consumption of petroleum-based fuels in a more 
cost-effective manner.

D. Summary of Costs and Benefits of the HD National Program

    This section summarizes the projected costs and benefits of the 
final NHTSA fuel consumption and EPA GHG emissions standards. These 
projections helped to inform the agencies' choices among the 
alternatives considered and provide further confirmation that the final 
standards are an appropriate choice within the spectrum of choices 
allowable under the agencies' respective statutory criteria. NHTSA and 
EPA have used common projected costs and benefits as the bases for our 
respective standards.
    The agencies have analyzed in detail the projected costs, fuel 
savings, and benefits of the final GHG and fuel consumption standards. 
Table I-5 shows estimated lifetime discounted program costs (including 
technological outlays), fuel savings, and benefits for all heavy-duty 
vehicles projected to be sold in model years 2014-2018 over these 
vehicles' lives. The benefits include impacts such as climate-related 
economic benefits from reducing emissions of CO2 (but not 
other GHGs) and reductions in energy security externalities caused by 
U.S. petroleum consumption and imports. The analysis also includes 
economic impacts stemming from additional heavy-duty vehicle use 
attributable to fuel savings, such as the economic damages caused by 
accidents, congestion and noise. Note that benefits reflect on 
estimated values for the social cost of carbon (SCC), as described in 
Section VIII.G.
    The costs, fuel savings, and benefits summarized here are slightly 
higher than at proposal, reflecting the use of 2009 (versus 2008) 
dollars, some minor changes to our cost estimates in response to 
comments, and a change to the 2011 Annual Energy Outlook (AEO) estimate 
of economic growth and future fuel prices. In aggregate, these changes 
lead to an increased estimate of the net benefits of the final action 
compared to the proposal.

 Table I-5--Estimated Lifetime Discounted Costs, Fuel Savings, Benefits,
    and Net Benefits for 2014-2018 Model Year Heavy-Duty Vehiclesa b
                            [Billions, 2009$]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
               Lifetime Present Value\c\--3% Discount Rate
------------------------------------------------------------------------
Program Costs...........................................            $8.1
Fuel Savings............................................             $50
Benefits................................................            $7.3
Net Benefits\d\.........................................             $49
------------------------------------------------------------------------
                  Annualized Value\e\--3% Discount Rate
------------------------------------------------------------------------
Annualized Costs........................................            $0.4
Fuel Savings............................................            $2.2
Annualized Benefits.....................................            $0.4
Net Benefits\d\.........................................            $2.2
------------------------------------------------------------------------
               Lifetime Present Value\c\--7% Discount Rate
------------------------------------------------------------------------
Program Costs...........................................            $8.1
Fuel Savings............................................             $34
Benefits................................................            $6.7
Net Benefits\d\.........................................             $33
------------------------------------------------------------------------
                  Annualized Value\e\--7% Discount Rate
------------------------------------------------------------------------
Annualized Costs........................................            $0.6
Fuel Savings............................................            $2.6
Annualized Benefits.....................................            $0.5
Net Benefits\d\.........................................            $2.5
------------------------------------------------------------------------
Notes:

[[Page 57126]]

 
\a\ The agencies estimated the benefits associated with four different
  values of a one ton CO2 reduction (model average at 2.5% discount
  rate, 3%, and 5%; 95th percentile at 3%), which each increase over
  time. For the purposes of this overview presentation of estimated
  costs and benefits, however, we are showing the benefits associated
  with the marginal value deemed to be central by the interagency
  working group on this topic: the model average at 3% discount rate, in
  2009 dollars. Section VIII.F provides a complete list of values for
  the 4 estimates.
\b\ Note that net present value of reduced GHG emissions is calculated
  differently than other benefits. The same discount rate used to
  discount the value of damages from future emissions (SCC at 5, 3, and
  2.5 percent) is used to calculate net present value of SCC for
  internal consistency. Refer to Section VIII.F for more detail.
\c\ Present value is the total, aggregated amount that a series of
  monetized costs or benefits that occur over time is worth now (in year
  2009 dollar terms), discounting future values to the present.
\d\ Net benefits reflect the fuel savings plus benefits minus costs.
\e\ The annualized value is the constant annual value through a given
  time period (2012 through 2050 in this analysis) whose summed present
  value equals the present value from which it was derived.

    Table I-6 shows the estimated lifetime reductions in CO2 
emissions (in million metric tons (MMT)) and fuel consumption for all 
heavy-duty vehicles sold in the model years 2014-2018. The values in 
Table I-6 are projected lifetime totals for each model year and are not 
discounted. The two agencies' standards together comprise the HD 
National Program, and the agencies' respective GHG emissions and fuel 
consumption standards, jointly, are the source of the benefits and 
costs of the HD National Program.

                   Table I-6--Estimated Lifetime Reductions in Fuel Consumption and CO2 Emissions for 2014-2018 Model Year HD Vehicles
--------------------------------------------------------------------------------------------------------------------------------------------------------
                 All heavy-duty vehicles                      2014 MY         2015 MY         2016 MY         2017 MY         2018 MY          Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fuel (billion gallons)..................................            4.0             3.6             3.6             5.1             5.8            22.1
Fuel (billion barrels)..................................            0.10            0.09            0.08            0.12            0.14            0.53
CO2 (MMT)a..............................................           50.2            44.8            44.0            62.8            71.7           273
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
\a\ Includes upstream and downstream CO2 reductions.

    Table I-7 shows the estimated lifetime discounted benefits for all 
heavy-duty vehicles sold in model years 2014-2018. Although the 
agencies estimated the benefits associated with four different values 
of a one ton CO2 reduction ($5, $22, $36, $66), for the 
purposes of this overview presentation of estimated benefits the 
agencies are showing the benefits associated with one of these marginal 
values, $22 per ton of CO2, in 2009 dollars and 2010 
emissions. Table I-7 presents benefits based on the $22 per ton of 
CO2 value. Section VIII.F presents the four marginal values 
used to estimate monetized benefits of CO2 reductions and 
Section VIII presents the program benefits using each of the four 
marginal values, which represent only a partial accounting of total 
benefits due to omitted climate change impacts and other factors that 
are not readily monetized. The values in the table are discounted 
values for each model year of vehicles throughout their projected 
lifetimes. The analysis includes other economic impacts such as energy 
security, and other externalities such as impacts on accidents, 
congestion and noise. However, the model year lifetime analysis 
supporting the program omits other impacts such as benefits related to 
non-GHG emission reductions.\40\ The lifetime discounted benefits are 
shown for one of four different SCC values considered by EPA and NHTSA. 
The values in Table I-7 do not include costs associated with new 
technology required to meet the GHG and fuel consumption standards.
---------------------------------------------------------------------------

    \40\ Non-GHG emissions and health-related impacts were estimated 
for the calendar year analysis. See Section VII for more information 
about non-GHG emission impacts and Section VIII for more information 
about non-GHG-related health impacts.

   Table I-7--Estimated Lifetime Discounted Benefits for 2014-2018 Model Year HD Vehicles Assuming the Model Average, 3% Discount Rate SCC Valuea b c
                                                               [billions of 2009 dollars]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                    Model year
                 Discount rate (percent)                 -----------------------------------------------------------------------------------------------
                                                               2014            2015            2016            2017            2018            Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
3.......................................................           $10.7            $9.4            $9.2           $13.2           $14.9             $57
7.......................................................             8.3             6.9             6.6             9.2            10.1              41
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ The analysis includes impacts such as the economic value of reduced fuel consumption and accompanying climate-related economic benefits from
  reducing emissions of CO2 (but not other GHGs), and reductions in energy security externalities caused by U.S. petroleum consumption and imports. The
  analysis also includes economic impacts stemming from additional heavy-duty vehicle use, such as the economic damages caused by accidents, congestion
  and noise.
\b\ Note that net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount rate used to discount the
  value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to calculate net present value of SCC for internal consistency. Refer to
  Section VIII.F for more detail, including a list of all four SCC values, which increase over time.
\c\ Benefits in this table include fuel savings.

    Table I-8 shows the agencies' estimated lifetime fuel savings, 
lifetime CO2 emission reductions, and the monetized net 
present values of those fuel savings and CO2 emission 
reductions. The gallons of fuel and CO2 emission reductions 
are projected lifetime values for all vehicles sold in the model years 
2014-2018. The

[[Page 57127]]

estimated fuel savings in billions of barrels and the GHG reductions in 
million metric tons of CO2 shown in Table I-8 are totals for 
the five model years throughout their projected lifetime and are not 
discounted. The monetized values shown in Table I-8 are the summed 
values of the discounted monetized-fuel consumption and monetized-
CO2 reductions for the five model years 2014-2018 throughout 
their lifetimes. The monetized values in Table I-8 reflect both a 3 
percent and a 7 percent discount rate as noted.

   Table I-8--Estimated Lifetime Reductions and Associated Discounted
         Monetized Benefits for 2014-2018 Model Year HD Vehicles
                   [Monetized values in 2009 dollars]
------------------------------------------------------------------------
                                        Amount        $ Value (billions)
------------------------------------------------------------------------
Fuel Consumption Reductions.....  0.53 billion        $50.1, 3% discount
                                   barrels.            rate $34.4, 7%
                                                       discount rate.
CO2 Emission Reductions \a\       273 MMT CO2.......  $5.8 \b\.
 Valued assuming $22/ton CO2 in
 2010.
------------------------------------------------------------------------
Notes:
\a\ Includes both upstream and downstream CO2 emission reductions.
\b\ Note that net present value of reduced CO2 emissions is calculated
  differently than other benefits. The same discount rate used to
  discount the value of damages from future emissions (SCC at 5, 3, and
  2.5 percent) is used to calculate net present value of SCC for
  internal consistency. Refer to Section VIII.F for more detail.

    Table I-9 shows the estimated incremental and total technology 
outlays for all heavy-duty vehicles for each of the model years 2014-
2018. The technology outlays shown in Table I-9 are for the industry as 
a whole and do not account for fuel savings associated with the 
program.

            Table I-9--Estimated Incremental Technology Outlays for 2014-2018 Model Year HD Vehicles
                                           [Billions of 2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                            2014 MY  2015 MY  2016 MY  2017 MY  2018 MY   Total
----------------------------------------------------------------------------------------------------------------
All Heavy-Duty Vehicles...................................     $1.6     $1.4     $1.5     $1.6     $2.0     $8.1
----------------------------------------------------------------------------------------------------------------

    Table I-10 shows the agencies' estimated incremental cost increase 
of the average new heavy-duty vehicle for each model year 2014-2018. 
The values shown are incremental to a baseline vehicle and are not 
cumulative.

         Table I-10--Estimated Incremental Increase in Average Cost for 2014-2018 Model Year HD Vehicles
                                             [2009 Dollars per unit]
----------------------------------------------------------------------------------------------------------------
                                                            2014 MY    2015 MY    2016 MY    2017 MY    2018 MY
----------------------------------------------------------------------------------------------------------------
Combination Tractors.....................................     $6,019     $5,871     $5,677     $6,413     $6,215
HD Pickups & Vans........................................        165        215        422        631      1,048
Vocational Vehicles......................................        329        320        397        387        378
----------------------------------------------------------------------------------------------------------------

    Both costs and benefits presented in this section are in comparison 
to a reference case with no improvements in fuel consumption or 
greenhouse gas emissions in model years 2014 to 2018.

E. Program Flexibilities

    For each of the heavy-duty vehicle and heavy-duty engine categories 
for which we are adopting respective standards, EPA and NHTSA are also 
finalizing provisions designed to give manufacturers a degree of 
flexibility in complying with the standards. These final provisions 
have enabled the agencies to consider overall standards that are more 
stringent and that will become effective sooner than we could consider 
with a more rigid program, one in which all of a manufacturer's similar 
vehicles or engines would be required to achieve the same emissions or 
fuel consumption levels, and at the same time.\41\ We believe that 
incorporating carefully structured regulatory flexibility provisions 
into the overall program is an important way to achieve each agency's 
goals for the program.
---------------------------------------------------------------------------

    \41\ NHTSA notes that it has greater flexibility in the HD 
program to include consideration of credits and other flexibilities 
in determining appropriate and feasible levels of stringency than it 
does in the light-duty CAFE program. Cf. 49 U.S.C. 32902(h), which 
applies to light-duty CAFE but not heavy-duty fuel efficiency under 
49 U.S.C. 32902(k).
---------------------------------------------------------------------------

    NHTSA's and EPA's flexibility provisions are essentially identical 
in structure and function. Within combination tractor and vocational 
vehicle categories and within heavy-duty engines, we are finalizing 
four primary types of flexibility: Averaging, banking, and trading 
(ABT) provisions; early credits; advanced technology credits (including 
hybrid powertrains); and innovative technology credit provisions. The 
final ABT provisions are patterned on existing EPA and NHTSA ABT 
programs and will allow a vehicle manufacturer to reduce CO2 
emission and fuel consumption levels further than the level of the 
standard for one or more vehicles to generate ABT credits. The 
manufacturer can use those credits to offset higher emission or fuel 
consumption levels in the same averaging set, ``bank'' the credits for 
later use, or ``trade'' the credits to another manufacturer. For HD 
pickups and vans, we are finalizing a fleet

[[Page 57128]]

averaging system very similar to the light-duty GHG and CAFE fleet 
averaging system.
    At proposal, we restricted the use of the ABT provisions of the 
program to vehicles or engines within the same regulatory subcategory. 
This meant that credit exchanges could only happen between similar 
vehicles meeting the same standards. We proposed this approach for two 
reasons. First, we were concerned about a level playing field between 
different manufacturers who may not participate equally in the various 
truck and engine markets covered in the regulation. Second, we were 
concerned about the uncertainties inherent in credit calculations that 
are based on projections of lifetime emissions for different vehicles 
in wholly different vehicle markets. In response to comments, we have 
revised our ABT provisions to provide greater flexibility while 
continuing to provide assurance that the projected reductions in fuel 
consumption and GHG emissions will be achieved. We are relaxing the 
restriction on averaging, banking, and trading of credits between the 
various regulatory subcategories, by defining three HD vehicle 
averaging sets: Light Heavy-Duty (Classes 2b-5); Medium Heavy-Duty 
(Class 6-7); and Heavy Heavy-Duty (Class 8). This allows the use of 
credits between vehicles within the same weight class. This means that 
a Class 8 day cab tractor can exchange credits with a Class 8 high roof 
sleeper tractor but not with a smaller Class 7 tractor. Also, a Class 8 
vocational vehicle can exchange credits with a Class 8 tractor. We are 
adopting these revisions based on comments from the regulated industry 
that convinced us these changes would allow the broadest trading 
possible while maintaining a level playing field among the various 
market segments. However, we are restricting trading between engines 
and chassis, even within the same vehicle class.
    The agencies believe that restricting trading to within the same 
eight classes as EPA's existing criteria pollutant program (i.e. Heavy-
Heavy Duty, Light Heavy-Duty, Medium Heavy-Duty), but not restricting 
trading between vehicle or engine type (such as combination tractors), 
and restricting between engines and chassis for the same vehicle type, 
is appropriate and reasonable. We do not expect emissions from engines 
and vehicles--when restricted by weight class--to be dissimilar. We 
therefore expect that the lifetime vehicle performance and emissions 
levels will be very similar across these defined categories, and the 
estimated credit calculations will fairly ensure the expected fuel 
consumption and GHG reductions.
    The agencies considered even broader averaging, banking, and 
trading provisions but decided that in this first phase of regulation, 
it would be prudent to start with the program described here, which 
will regulate greenhouse gas emissions and fuel consumption from this 
sector for the first time and provide considerable early reductions as 
well as opportunities to learn about technical and other issues that 
can inform future rulemakings. In the future we intend to consider 
whether additional cost savings could be realized through broader 
trading provisions and whether such provisions could be designed so as 
to address any other relevant concerns.
    Reducing the cost of regulation through broader use of market tools 
is a high priority for the Administration. See Executive Order 13563 
and in particular section 1(b)(5) and section 4. Consistent with this 
principle, we intend to seek public comment through a Notice of Data 
Availability after credit trading begins in 2013, the first year we 
expect manufacturers to begin certifying 2014 model year vehicles, on 
whether broader credit trading is more appropriate in developing the 
next phase of heavy-duty regulations. We believe that input will be 
better informed by the work the agencies and the regulated industry 
will have put into implementing this first phase of heavy-duty 
regulations.
    Through this public process, emphasizing the Administration's 
strong preference for flexible approaches and maximizing the use of 
market tools, the agencies intend to fully consider whether broader 
credit trading is more appropriate in developing the next phase of 
heavy-duty regulations.
    This program thus does not allow credits to be exchanged between 
heavy-duty vehicles and light-duty vehicles, nor can credits be traded 
from heavy-duty vehicle fleets to light-duty vehicle fleets and vice 
versa.
    The engine ABT provisions are also changed from the proposal and 
now are the same as in EPA's existing criteria pollutant emission 
rules. The agencies have broadened the averaging sets to include both 
FTP-certified and SET-certified engines in the same averaging set. For 
example, a SET-certified engine intended for a Class 8 tractor can 
exchange credits with a FTP-certified engine intended for a Class 8 
vocational vehicle.
    The agencies are finalizing three year deficit carry-forward 
provisions for heavy-duty engines and vehicles within a limited time 
frame. This flexibility is expected to provide an opportunity for 
manufacturers to make necessary technological improvements and reduce 
the overall cost of the program without compromising overall 
environmental and fuel economy objectives. This flexibility, similar to 
the flexibility the agencies have offered under the light-duty vehicle 
program, is intended to assist the broad goal of harmonizing the two 
agencies' standards while preserving the flexibility of manufacturers 
of vehicles and engines in meeting the standards, to the extent 
appropriate and required by law. During the MYs 2014-2018 manufacturers 
are expected to go through the normal business cycle of redesigning and 
upgrading their heavy-duty engine and vehicle products, and in some 
cases introducing entirely new vehicles and engines not on the market 
today. As explained in the following paragraph, the carry-forward 
provision will allow manufacturers the time needed to incorporate 
technology to achieve GHG reductions and improve fuel economy during 
the vehicle redesign process.
    We received comments from Center for Biological Diversity against 
the need to offer the deficit carry-forward flexibility. CBD has stated 
that allowing manufacturers to carry-forward deficits for up to three 
years would incentivize delays in investment and technological 
innovation and allow for the generation of additional tons of GHG 
emissions that may be prevented today. However, the deficit carry-
forward flexibility (as well as ABT generally) has enabled the agencies 
to consider overall standards that are more stringent and that will 
become effective at an earlier period than we could consider with a 
more rigid program. The agencies also believe this flexibility is an 
important aspect of the program, as it avoids the much higher costs 
that would occur if manufacturers needed to add or change technology at 
times other than their scheduled redesigns, i.e. the cost of adopting a 
new engine or vehicle platform mid-production or mid-design. This time 
period would also provide manufacturers the opportunity to plan for 
compliance using a multi-year time frame, again consistent with normal 
business practice. Over these four model years, there would be an 
opportunity for manufacturers to evaluate practically all of their 
vehicle and engine model platforms and add technology in a cost 
effective way to control GHG emissions and improve fuel economy.
    As noted above, in addition to ABT, the other primary flexibility 
provisions in this program involve opportunities to generate early 
credits, advanced technology credits (including for use of

[[Page 57129]]

hybrid powertrains), and innovative technology credits. For the early 
credits and advanced technology credits, the agencies sought comment on 
the appropriateness of providing a 1.5x multiplier as an incentive for 
their use. We received a number of comments supporting the idea of a 
credit multiplier, arguing it was an appropriate means to incentivize 
the early compliance and advanced technologies the agencies sought. We 
received other comments suggesting a multiplier was unnecessary. After 
considering the comments, the agencies have decided to finalize a 1.5x 
multiplier consistent with our request for comments. We believe that 
given the very short lead time of the program and the nascent nature of 
the advanced technologies identified in the proposal, that a 1.5x 
multiplier is an effective means to bring technology forward into the 
heavy-duty sector sooner than would otherwise occur. In addition, 
advanced technology credits could be used anywhere within the heavy 
duty sector (including both vehicles and engines), but early credits 
would be restricted to use within the same defined averaging set 
generating the credit.
    For other technologies which can reduce CO2 and fuel 
consumption, but for which there do not yet exist established methods 
for quantifying reductions, the agencies still wish to encourage the 
development of such innovative technologies, and are therefore adopting 
special ``innovative technology'' credits. These innovative technology 
credits will apply to technologies that are shown to produce emission 
and fuel consumption reductions that are not adequately recognized on 
the current test procedures and that are not yet in widespread use in 
the heavy-duty sector. Manufacturers will need to quantify the 
reductions in fuel consumption and CO2 emissions that the 
technology is expected to achieve, above and beyond those achieved on 
the existing test procedures. As with ABT, the use of innovative 
technology credits will only be allowed for use among vehicles and 
engines of the same defined averaging set generating the credit, as 
described above. The credit multiplier will not be used for innovative 
technology credits.
    CBD argued that including any opportunities for manufacturers to 
earn credits in the final rule would violate NHTSA's statutory mandate 
to implement a program designed to achieve the maximum feasible 
improvement.
    NHTSA strongly believes that creating credit flexibilities for 
manufacturers for this first phase of the HD National Program is fully 
consistent with the agency's obligation to develop a fuel efficiency 
improvement program designed to achieve the maximum feasible 
improvement. EISA gives NHTSA broad authority to develop ``compliance 
and enforcement protocols'' that are ``appropriate, cost-effective, and 
technologically feasible,'' and the agency believes that compliance 
flexibilities such as the opportunity to earn and use credits to meet 
the standards are a reasonable and appropriate interpretation of that 
authority, along with the other compliance and enforcement provisions 
developed for this final rule. Unlike in NHTSA's light-duty program, 
where the agency is restricted from considering the availability of 
credits in determining the maximum feasible level of stringency for the 
fuel economy standards,\42\ in this HD National Program, NHTSA and EPA 
have based the levels of stringency in part on our assumptions of the 
use of available flexibilities that have been built into the program to 
incentivize over-compliance in some respects, to balance out potential 
under-compliance in others.
---------------------------------------------------------------------------

    \42\ See 49 U.S.C. 32902(h).
---------------------------------------------------------------------------

    By assuming the use of credits for compliance, the agencies were 
able to set the fuel consumption/GHG standards at more stringent levels 
than would otherwise have been feasible. Greater improvements in fuel 
efficiency will occur under more stringent standards; manufacturers 
will simply have greater flexibility to determine where and how to make 
those improvements than they would have without credit options. 
Further, this is consistent with EOs 12866 and 13563, which encourage 
agencies to design regulations that promote innovation and flexibility 
where possible.\43\
---------------------------------------------------------------------------

    \43\ EO 12866 states that an agency must ``design its 
regulations in the most cost-effective manner to achieve the 
regulatory objective * * * consider[ing] incentives for innovation * 
* * [and] flexibility,'' among other factors; EO 13563 directs 
agencies to ``seek to identify, as appropriate, means to achieve 
regulatory goals that are designed to promote innovation,'' and 
``identify and consider regulatory approaches that * * * maintain 
flexibility.''
---------------------------------------------------------------------------

    A detailed discussion of each agency's ABT, early credit, advanced 
technology, and innovative technology provisions for each regulatory 
category of heavy-duty vehicles and engines is found in Section IV 
below.

F. EPA and NHTSA Statutory Authorities

(1) EPA Authority
    Title II of the CAA provides for comprehensive regulation of mobile 
sources, authorizing EPA to regulate emissions of air pollutants from 
all mobile source categories. When acting under Title II of the CAA, 
EPA considers such issues as technology effectiveness, its cost (both 
per vehicle, per manufacturer, and per consumer), the lead time 
necessary to implement the technology, and based on this the 
feasibility and practicability of potential standards; the impacts of 
potential standards on emissions reductions of both GHGs and non-GHGs; 
the impacts of standards on oil conservation and energy security; the 
impacts of standards on fuel savings by customers; the impacts of 
standards on the truck industry; other energy impacts; as well as other 
relevant factors such as impacts on safety.
    This final action implements a specific provision from Title II, 
section 202(a).\44\ Section 202(a)(1) of the CAA states that ``the 
Administrator shall by regulation prescribe (and from time to time 
revise) * * * standards applicable to the emission of any air pollutant 
from any class or classes of new motor vehicles * * *, which in his 
judgment cause, or contribute to, air pollution which may reasonably be 
anticipated to endanger public health or welfare.'' With EPA's December 
2009 final findings that certain greenhouse gases may reasonably be 
anticipated to endanger public health and welfare and that emissions of 
GHGs from section 202 (a) sources cause or contribute to that 
endangerment, section 202(a) requires EPA to issue standards applicable 
to emissions of those pollutants from new motor vehicles.
---------------------------------------------------------------------------

    \44\ See 42 U.S.C. 7521 (a). A number of commenters believed 
that the GHG program was being adopted pursuant to section 202 
(a)(3)(A) and that the lead time requirements of section 202 
(a)(3)(C) therefore apply. This is mistaken. Section 202 (a)(3)(A) 
applies to standards for emissions of hydrocarbons, carbon monoxide, 
oxides of nitrogen, and particulate matter from heavy-duty vehicles 
and engines. This does not include the GHGs regulated under the 
standards in today's action. This comment is addressed further in 
the Response to Comment document.
---------------------------------------------------------------------------

    Any standards under CAA section 202(a)(1) ``shall be applicable to 
such vehicles * * * for their useful life.'' Emission standards set by 
the EPA under CAA section 202(a)(1) are technology-based, as the levels 
chosen must be premised on a finding of technological feasibility. 
Thus, standards promulgated under CAA section 202(a) are to take effect 
only ``after providing such period as the Administrator finds necessary 
to permit the development and application of the requisite technology, 
giving appropriate consideration to the cost of compliance within such 
period'' (section 202(a)(2);

[[Page 57130]]

see also NRDC v. EPA, 655 F. 2d 318, 322 (DC Cir. 1981)). EPA is 
afforded considerable discretion under section 202(a) when assessing 
issues of technical feasibility and availability of lead time to 
implement new technology. Such determinations are ``subject to the 
restraints of reasonableness'', which ``does not open the door to 
`crystal ball' inquiry.'' NRDC, 655 F. 2d at 328, quoting International 
Harvester Co. v. Ruckelshaus, 478 F. 2d 615, 629 (DC Cir. 1973). 
However, ``EPA is not obliged to provide detailed solutions to every 
engineering problem posed in the perfection of the trap-oxidizer. In 
the absence of theoretical objections to the technology, the agency 
need only identify the major steps necessary for development of the 
device, and give plausible reasons for its belief that the industry 
will be able to solve those problems in the time remaining. The EPA is 
not required to rebut all speculation that unspecified factors may 
hinder `real world' emission control.'' NRDC, 655 F. 2d at 333-34. In 
developing such technology-based standards, EPA has the discretion to 
consider different standards for appropriate groupings of vehicles 
(``class or classes of new motor vehicles''), or a single standard for 
a larger grouping of motor vehicles (NRDC, 655 F. 2d at 338).
    Although standards under CAA section 202(a)(1) are technology-
based, they are not based exclusively on technological capability. EPA 
has the discretion to consider and weigh various factors along with 
technological feasibility, such as the cost of compliance (See section 
202(a) (2)), lead time necessary for compliance (section 202(a)(2)), 
safety (See NRDC, 655 F. 2d at 336 n. 31) and other impacts on 
consumers, and energy impacts associated with use of the technology. 
See George E. Warren Corp. v. EPA, 159 F.3d 616, 623-624 (DC Cir. 1998) 
(ordinarily permissible for EPA to consider factors not specifically 
enumerated in the CAA). See also Entergy Corp. v. Riverkeeper, Inc., 
129 S.Ct. 1498, 1508-09 (2009) (congressional silence did not bar EPA 
from employing cost-benefit analysis under Clean Water Act absent some 
other clear indication that such analysis was prohibited; rather, 
silence indicated discretion to use or not use such an approach as the 
agency deems appropriate).
    In addition, EPA has clear authority to set standards under CAA 
section 202(a) that are technology forcing when EPA considers that to 
be appropriate, but is not required to do so (as compared to standards 
set under provisions such as section 202(a)(3) and section 
213(a)(3)).\45\ EPA has interpreted a similar statutory provision, CAA 
section 231, as follows:
---------------------------------------------------------------------------

    \45\ One commenter mistakenly stated that section 202 (a) 
standards must be technology-forcing, but the provision plainly does 
not require EPA to adopt technology-forcing standards. See further 
discussion in Section III.A below.
---------------------------------------------------------------------------

    While the statutory language of section 231 is not identical to 
other provisions in title II of the CAA that direct EPA to establish 
technology-based standards for various types of engines, EPA interprets 
its authority under section 231 to be somewhat similar to those 
provisions that require us to identify a reasonable balance of 
specified emissions reduction, cost, safety, noise, and other factors. 
See, e.g., Husqvarna AB v. EPA, 254 F.3d 195 (DC Cir. 2001) (upholding 
EPA's promulgation of technology-based standards for small non-road 
engines under section 213(a)(3) of the CAA). However, EPA is not 
compelled under section 231 to obtain the ``greatest degree of emission 
reduction achievable'' as per sections 213 and 202 of the CAA, and so 
EPA does not interpret the Act as requiring the agency to give 
subordinate status to factors such as cost, safety, and noise in 
determining what standards are reasonable for aircraft engines. Rather, 
EPA has greater flexibility under section 231 in determining what 
standard is most reasonable for aircraft engines, and is not required 
to achieve a ``technology forcing'' result (70 FR 69664 and 69676, 
November 17, 2005).
    This interpretation was upheld as reasonable in NACAA v. EPA, 489 
F.3d 1221, 1230 (DC Cir. 2007). CAA section 202(a) does not specify the 
degree of weight to apply to each factor, and EPA accordingly has 
discretion in choosing an appropriate balance among factors. See Sierra 
Club v. EPA, 325 F.3d 374, 378 (DC Cir. 2003) (even where a provision 
is technology-forcing, the provision ``does not resolve how the 
Administrator should weigh all [the statutory] factors in the process 
of finding the `greatest emission reduction achievable' ''). See also 
Husqvarna AB v. EPA, 254 F. 3d 195, 200 (DC Cir. 2001) (great 
discretion to balance statutory factors in considering level of 
technology-based standard, and statutory requirement ``to [give 
appropriate] consideration to the cost of applying * * * technology'' 
does not mandate a specific method of cost analysis); see also Hercules 
Inc. v. EPA, 598 F. 2d 91, 106 (DC Cir. 1978) (``In reviewing a 
numerical standard the agencies must ask whether the agency's numbers 
are within a zone of reasonableness, not whether its numbers are 
precisely right''); Permian Basin Area Rate Cases, 390 U.S. 747, 797 
(1968) (same); Federal Power Commission v. Conway Corp., 426 U.S. 271, 
278 (1976) (same); Exxon Mobil Gas Marketing Co. v. FERC, 297 F. 3d 
1071, 1084 (DC Cir. 2002) (same).
(a) EPA Testing Authority
    Under section 203 of the CAA, sales of vehicles are prohibited 
unless the vehicle is covered by a certificate of conformity. EPA 
issues certificates of conformity pursuant to section 206 of the Act, 
based on (necessarily) pre-sale testing conducted either by EPA or by 
the manufacturer. The Heavy-duty Federal Test Procedure (Heavy-duty 
FTP) and the Supplemental Engine Test (SET) are used for this purpose. 
Compliance with standards is required not only at certification but 
throughout a vehicle's useful life, so that testing requirements may 
continue post-certification. Useful life standards may apply an 
adjustment factor to account for vehicle emission control deterioration 
or variability in use (section 206(a)).
    EPA established the Light-duty FTP for emissions measurement in the 
early 1970s. In 1976, in response to the Energy Policy and Conservation 
Act, EPA extended the use of the Light-duty FTP to fuel economy 
measurement (See 49 U.S.C. 32904(c)). EPA can determine fuel efficiency 
of a vehicle by measuring the amount of CO2 and all other 
carbon compounds (e.g., total hydrocarbons and carbon monoxide (CO)), 
and then, by mass balance, calculating the amount of fuel consumed.
(b) EPA Enforcement Authority
    Section 207 of the CAA grants EPA broad authority to require 
manufacturers to remedy vehicles if EPA determines there are a 
substantial number of noncomplying vehicles. In addition, section 205 
of the CAA authorizes EPA to assess penalties of up to $37,500 per 
vehicle for violations of various prohibited acts specified in the CAA. 
In determining the appropriate penalty, EPA must consider a variety of 
factors such as the gravity of the violation, the economic impact of 
the violation, the violator's history of compliance, and ``such other 
matters as justice may require.''
(2) NHTSA Authority
    In 1975, Congress enacted the Energy Policy and Conservation Act 
(EPCA), mandating a regulatory program for motor vehicle fuel economy 
to meet the various facets of the need to conserve energy. In December 
2007, Congress

[[Page 57131]]

enacted the Energy Independence and Securities Act (EISA), amending 
EPCA to require, among other things, the creation of a medium- and 
heavy-duty fuel efficiency program for the first time. This mandate in 
EISA represents a major step forward in promoting EPCA's goals of 
energy independence and security, and environmental and national 
security.
    NHTSA has primary responsibility for fuel economy and consumption 
standards, and assures compliance with EISA through rulemaking, 
including standard-setting; technical reviews, audits and studies; 
investigations; and enforcement of implementing regulations including 
penalty actions. This final action implements Section 32902(k)(2) of 
EISA, which instructs NHTSA to create a fuel efficiency improvement 
program for ``commercial medium- and heavy-duty on-highway vehicles and 
work trucks'' \46\ by rulemaking, which is to include standards, test 
methods, measurement metrics, and enforcement protocols. See 49 U.S.C. 
32902(k)(2). Congress directed that the standards, test methods, 
measurement metrics, and compliance and enforcement protocols be 
``appropriate, cost-effective, and technologically feasible'' for the 
vehicles to be regulated, while achieving the ``maximum feasible 
improvement'' in fuel efficiency.
---------------------------------------------------------------------------

    \46\ ``Commercial medium- and heavy-duty on-highway vehicles'' 
are defined at 49 U.S.C. 32901(a)(7), and ``work trucks'' are 
defined at (a)(19).
---------------------------------------------------------------------------

    NHTSA has clear authority to design and implement a fuel efficiency 
program for vehicles and work trucks under EISA, and was given broad 
discretion to balance the statutory factors in Section 32902(k)(2) in 
developing fuel consumption standards to achieve the maximum feasible 
improvement. Since this is the first rulemaking that NHTSA has 
conducted under 49 U.S.C. 32902(k)(2), the agency interpreted these 
elements and factors in the context of setting standards, choosing 
metrics, and determining test methods and compliance/enforcement 
mechanisms. Discussion of the application of these factors can be found 
in Section III below. Congress also gave NHTSA the authority to set 
separate standards for different classes of these vehicles, but 
required that all standards adopted provide not less than four full 
model years of regulatory lead-time and three full model years of 
regulatory stability.
    In EISA, Congress required NHTSA to prescribe separate average fuel 
economy standards for passenger cars and light trucks in accordance 
with the provisions in 49 U.S.C. Section 32902(b), and to prescribe 
standards for work trucks and commercial medium- and heavy-duty 
vehicles in accordance with the provisions in 49 U.S.C. 32902(k). See 
49 U.S.C. Section 32902(b)(1). Congress also added in EISA a 
requirement that NHTSA shall issue regulations prescribing fuel economy 
standards for at least 1, but not more than 5, model years. See 49 
U.S.C. 32902(b)(3)(B). For purposes of the fuel efficiency standards 
that the agency proposed for HD vehicles and engines, the NPRM stated 
an interpretation of the statute that the 5-year maximum limit did not 
apply to standards promulgated in accordance with 49 U.S.C. 32902(k), 
given the language in Section 32902(b)(1). Based on this 
interpretation, NHTSA proposed that the standards ultimately finalized 
for HD vehicles and engines would remain in effect indefinitely at 
their 2018 or 2019 model year levels until amended by a future 
rulemaking action. In any future rulemaking action to amend the 
standards, NHTSA would ensure not less than four full model years of 
regulatory lead-time and three full model years of regulatory 
stability. NHTSA sought comment on its interpretation of EISA.
    Robert Bosch LLC (Bosch) commented that the absence of an 
expiration date for the standards proposed in the NPRM could violate 49 
U.S.C. 32902, which it interpreted as requiring the MD/HD program to 
have standards that expire in five years. Section 32902(k)(3), which 
lays out the requirements for the MD/HD program, specifies the minimum 
regulatory lead and stability times, as described above, but does not 
specify a maximum duration period. In contrast, Section 32902(b)(3)(B) 
lays out the minimum and maximum durations of standards to be 
established in a rulemaking for the light-duty program, but prescribes 
no minimum lead or stability time. Bosch argued that as 49 U.S.C. 
Section 32902(k)(3) does not require a maximum duration period, 
Congress intended that NHTSA take the maximum duration period specified 
for the light-duty program in Section 32902(b)(3)(B), five years, and 
apply it to Section 32902(k)(3). Bosch also argued, however, that the 
minimum duration period should not be carried over from the light-duty 
to the heavy-duty section, as a minimum duration period for HD was 
specified in Section 32902(k)(3).
    NHTSA has revisited this issue and continues to believe that it is 
reasonable to assume that if Congress intended for the HD/MD regulatory 
program to be limited by the timeline prescribed in Subsection 
(b)(3)(B), it would have either mentioned HD/MD vehicles in that 
subsection or included the same timeline in Subsection (k).\47\ In 
addition, in order for Subsection (b)(3)(B) to be interpreted to apply 
to Subsection (k), the agency would need to give less than full weight 
to the earlier phrase in the statute directing the Secretary to 
prescribe standards for ``work trucks and commercial medium-duty or 
heavy-duty on-highway vehicles in accordance with Subsection (k).'' 49 
U.S.C. 32902(b)(1)(C). Instead, this direction would need to be read to 
mean ``in accordance with Subsection (k) and the remainder of 
Subsection (b).'' NHTSA believes this interpretation would be 
inappropriate. Interpreting ``in accordance with Subsection (k)'' to 
mean something indistinct from ``in accordance with this Subsection'' 
goes against the canon that statutes should not be interpreted in a way 
that ``render[s] language superfluous.'' Dobrova v. Holder, 607 F.3d 
297, 302 (2d Cir. 2010), quoting Mendez v. Holder, 566 F. 3d 316, 321-
22 (2d Cir. 2009). Based on this reasoning, NHTSA believes the more 
reasonable and appropriate approach is reflected in the proposal, and 
the final rules therefore follow this approach.
---------------------------------------------------------------------------

    \47\ ``[W]here Congress includes particular language in one 
section of a statute but omits it in another section of the same 
Act, it is generally presumed that Congress acts intentionally and 
purposely in the disparate inclusion or exclusion.'' Russello v. 
United States, 464 U.S. 16, 23 (1983), quoting U.S. v. Wong Kim Bo, 
472 F.2d 720, 722 (5th Cir 1972)., See also Mayo v. Questech, Inc., 
727 F.Supp. 1007, 1014 (E.D.Va. 1989) (conspicuous absence of 
provision from section where inclusion would be most logical signals 
Congress did not intend for it to be implied).
---------------------------------------------------------------------------

    Another commenter, CBD, expressed concern that lack of an 
expiration date meant that the standards would remain indefinitely, 
thus forgoing the possibility of increased stringency in the future. 
CBD argued that this violated NHTSA's statutory duty to set maximum 
feasible standards. NHTSA disagrees that the indefinite duration of the 
standards in this rule would prevent the agency from setting future 
standards at the maximum feasible level in future rulemakings. The 
absence of an expiration date for these standards should not be 
interpreted to mean that there will be no future rulemakings to 
establish new MD/HD fuel efficiency standards for MYs 2019 and beyond--
the agencies have already previewed the possibility of such a 
rulemaking in other parts of this final rule preamble. Therefore, NHTSA 
believes this concern is unnecessary.

[[Page 57132]]

(a) NHTSA Testing Authority
    49 U.S.C. Section 32902(k)(2) states that NHTSA must adopt and 
implement appropriate, cost-effective, and technologically feasible 
test methods and measurement metrics as part of the fuel efficiency 
improvement program. For this program, manufacturers will test and 
conduct modeling to determine GHG emissions and fuel consumption 
performance, and EPA and NHTSA will perform validation testing. The 
results of the validation tests will be used by EPA to create a 
finalized reporting that confirms the manufacturer's final model year 
GHG emissions and fuel consumption results, which each agency will use 
to enforce compliance with its standards.
(v) NHTSA Enforcement Authority
(i) Overview
    The NPRM proposed a compliance and enforcement program that 
included civil penalties for violations of the fuel efficiency 
standards. 49 U.S.C. 32902(k)(2) states that NHTSA must adopt and 
implement appropriate, cost-effective, and technologically feasible 
compliance and enforcement protocols for the fuel efficiency 
improvement program. Congress gave DOT broad discretion to fashion its 
fuel efficiency improvement program and thus necessarily did not speak 
directly or specifically as to the nature of the compliance and 
enforcement protocols that would be best suited for effectively 
supporting the yet-to-be-designed-and-established program. Instead, it 
left the matter generally to the Secretary. Congress' approach is 
unlike CAFE enforcement for passenger cars and light trucks, where 
Congress specified the precise details of a program and provided that a 
manufacturer either complies with standards or pays civil penalties.
    The statute is silent with respect to how ``protocol'' should be 
interpreted. The term ``protocol'' is imprecise and thus Congress' 
choice of that term affords the agency substantial breadth of 
discretion. For example, in a case interpreting Section 301(c)(2) of 
the Comprehensive Environmental Response, Compensation, and Liability 
Act (CERCLA), the DC Circuit noted that the word ``protocols'' has many 
definitions that are not much help. Kennecott Utah Copper Corp., Inc. 
v. U.S. Dept. of Interior, 88 F.3d. 1191, 1216 (DC Cir. 1996). Section 
301(c)(2) of CERCLA prescribed the creation of two types of procedures 
for conducting natural resources damages assessments. The regulations 
were to specify (a) ``standard procedures for simplified assessments 
requiring minimal field observation'' (the ``Type A'' rules), and (b) 
``alternative protocols for conducting assessments in individual 
cases'' (the ``Type B'' rules).\48\ The court upheld the challenged 
provisions, which were a part of a set of rules establishing a step-by-
step procedure to evaluate options based on certain criteria, and to 
make a decision and document the results.
---------------------------------------------------------------------------

    \48\ State of Ohio v. U.S. Dept. of Interior, 880 F.2d 432, 439 
(DC Cir. 1989).
---------------------------------------------------------------------------

    Taking the considerations above into account, including Congress' 
instructions to adopt and implement compliance and enforcement 
protocols, and the Secretary's authority to formulate policy and make 
rules to fill gaps left, implicitly or explicitly, by Congress, the 
agency interpreted ``protocol'' in the context of EISA as authorizing 
the agency to determine both whether manufacturers have complied with 
the standards, and to establish suitable and reasonable enforcement 
mechanisms and decision criteria for non-compliance. Therefore, NHTSA 
interpreted its authority to develop an enforcement program to include 
the authority to determine and assess civil penalties for non-
compliance.
    Several commenters disagreed with this interpretation. Volvo and 
EMA commented that the penalties proposed by NHTSA exceeded the 
authority granted to the agency by Congress, and Volvo commented that 
the fact that Congress did not adopt an entirely new statute for the HD 
program should be interpreted to mean that provisions adopted for the 
light-duty program should apply to the HD program as well. Daimler 
argued that it was likely that EISA did not give NHTSA the authority to 
assess civil penalties, and Navistar and EMA argued that NHTSA could 
not have the authority as Congress did not expressly grant it.
    NHTSA continues to believe that it is reasonable to interpret 
``compliance and enforcement protocols'' to include authority to impose 
civil penalties. Where a statute does not specify an approach, the 
discretion to do so is left to the agency. When Congress has 
``explicitly left a gap for an agency to fill, there is an express 
delegation of authority to the agency to elucidate a specific provision 
of the statute by regulation.'' United States. v. Mead, 533 U.S. 218, 
227 (2001), quoting Chevron v. NRDC, 467 U.S. 837, 843-44 (1984). The 
delegation of authority may be implicit rather than express. Id. at 
229. NHTSA believes it would be unreasonable to assume that Congress 
intended to create a hollow regulatory program without a mechanism for 
effective enforcement. Further, interpreting ``enforcement protocols'' 
to mean not more than ``compliance protocols'' would go against the 
canon noted above that statutes should not be interpreted in a way that 
``render[s] language superfluous.'' Dobrova v. Holder, 607 F.3d 297, 
302 (2d Cir. 2010), quoting Mendez v. Holder 566 F. 3d 316, 321-22 (2d 
Cir. 2009). The interpretation urged by the commenters would render an 
entire program superfluous.
    Further, NHTSA believes that Congress would have anticipated that 
compliance and enforcement protocols would include civil penalties for 
the HD sector, given that penalties are an integral part of a product 
standards program and given the long precedent of civil penalties for 
the light-duty sector. The agency disagrees with the argument that the 
HD program would have appeared in a wholly separate statute if Congress 
had not intended the penalty program for light-duty to apply to it. The 
inclusion of the MD/HD program in Title 329 does not mean that Congress 
intended for the boundaries and differences between the separate 
sections to be ignored. Rather, this argument leads to the opposite 
conclusion that the fact that Congress created a new section for the HD 
program, instead of simply amending the existing light-duty program to 
include ``work trucks and other vehicles'' in addition to automobiles, 
means the agency should assume that Congress acted intentionally when 
it created two wholly separate programs and respect their distinctions. 
Therefore, consistent with the statutory interpretation proposed in the 
NPRM, the final rule includes penalties for non-compliance with the 
fuel efficiency standards.
(ii) Penalty Levels
    NHTSA proposed to adopt penalty levels equal to those in EPA's 
existing heavy-duty program, in order to provide adequate deterrence as 
well as consistency with the GHG regulation. The proposed maximum 
penalty levels were $37,500.00 per vehicle or engine.
    Several manufacturers commented that the penalty levels should be 
limited to those mandated in the light-duty program. Volvo and Daimler 
argued that Congress intended lower penalties for the HD program than 
were proposed in the NPRM, because they believed that Congress had 
expressly or implicitly intended for the HD program to be included in 
the penalty calculation of Section 32912(b). That section prescribes 
penalty levels for violators under Section 32902 of ``$5 multiplied

[[Page 57133]]

by each tenth (0.1) of a mile a gallon by which the applicable average 
fuel economy standard under that section exceeds the average fuel 
economy,'' \49\ calculated and applied to automobiles. Volvo further 
argued that NHTSA was relying upon the CAA as the statutory basis for 
the penalty levels.
---------------------------------------------------------------------------

    \49\ This fine was increased by 49 CFR 578.6, which provides 
that ``Except as provided in 49 U.S.C. 32912(c), a manufacturer that 
violates a standard prescribed for a model year under 49 U.S.C. 
32902 is liable to the United States Government for a civil penalty 
of $5.50 multiplied by each 0.1 of a mile a gallon by which the 
applicable average fuel economy standard under that section exceeds 
the average fuel economy.''
---------------------------------------------------------------------------

    NHTSA recognizes that Section 329 contains a detailed penalty 
scheme, for light-duty vehicle CAFE standards. However, Section 
32902(k)(2) explicitly directs NHTSA to ``adopt and implement 
appropriate test methods, measurement metrics, fuel economy standards, 
and compliance and enforcement protocols,'' in the creation of the new 
HD program. NHTSA continues to believe that this broad Congressional 
mandate should be interpreted based on a plain text reading, which 
includes the authority to determine compliance and enforcement 
protocols that will be effective and appropriate for this new sector of 
regulation. NHTSA also believes that reading Section 32912 to apply to 
the new HD program would contradict Congress' broad mandate for the 
agency to establish new measurement metrics and a compliance and 
enforcement program. Further, interpreting the requirement to create 
``enforcement protocols'' for HD vehicles to mean that NHTSA should 
rely on the enforcement provisions for light-duty vehicles would go 
against the canon noted above that statutes should not be interpreted 
in a way that ``render[s] language superfluous.'' Dobrova v. Holder, 
607 F.3d 297, 302 (2d Cir. 2010), quoting Mendez v. Holder 566 F. 3d 
316, 321-22 (2d Cir. 2009).
    NHTSA believes that Section 32912 does not apply to the new HD 
program for several other reasons. First, this section uses a fuel 
economy metric, miles/gallon, while the HD program is built around a 
fuel consumption metric, per the requirement to develop a ``fuel 
efficiency improvement program'' and the agencies' conclusion, 
supported by NAS, that a fuel consumption metric is a much more 
reasonable choice than a fuel economy metric for HD vehicles given 
their usage as work vehicles. Second, this section specifies a 
calculation for automobiles, a vehicle class which is confined to the 
light-duty rule. In addition, the HD program prescribes fuel 
consumption standards, not average fuel economy standards.
    Finally, NHTSA believes that if Congress had intended for a pre-
determined penalty scheme to apply to the new HD program, it would have 
been specific. Instead, Congress explicitly directed the agency to 
develop a new measurement, compliance, and enforcement scheme. 
Consistent with the statutory interpretation of the duration of the 
standards, NHTSA believes that if Congress intended for particular 
penalty levels to be used in Section 32902(k)(3), it would have either 
included a reference to those levels or included a reference in 32912 
to the vehicles and metrics regulated by 32902(k)(3). See Russello v. 
United States, 464 U.S. 16, 23 (1983), quoting United States v. Wong 
Kim Bo, 472 F.2d 720, 722 (5th Cir 1972) (``[W]here Congress includes 
particular language in one section of a statute but omits it in another 
section of the same Act, it is generally presumed that Congress acts 
intentionally and purposely in the disparate inclusion or exclusion.'') 
Instead, the absence of such language could mean either that Congress 
did not contemplate the specific penalty levels to be used, or that 
Congress left the choice of specific penalty levels to the agency. See 
Alliance for Community Media v. F.C.C. 529 F. 3d 763, 779 (6th Cir. 
2008) (absence of a statutory deadline in one section but not others 
meant that Congress authorized but did not require it in that section).
    NHTSA believes that, based on EPA's experience regulating this 
sector for criteria pollutants, the proposed maximum penalty is at an 
appropriate level to create deterrence for non-compliance, while at the 
same time, not so high as to create undue hardship for manufacturers. 
Therefore, the final rule retains the maximum penalty level proposed in 
the NPRM.

G. Future HD GHG and Fuel Consumption Rulemakings

    This final action represents a first regulatory step by NHTSA and 
EPA to address the multi-faceted challenges of reducing fuel use and 
greenhouse gas emissions from these vehicles. By focusing on existing 
technologies and well-developed regulatory tools, the agencies are able 
to adopt rules that we believe will produce real and important 
reductions in GHG emissions and fuel consumption within only a few 
years. Within the context of this regulatory time frame, our program is 
very aggressive--with limited lead time compared to historic heavy-duty 
regulations--but pragmatic in the context of technologies that are 
available and that can be reasonably implemented during the regulatory 
time frame.
    While we are now only finalizing this first step, it is worthwhile 
to consider how the next regulatory step may be designed. Technologies 
such as hybrid drivetrains, advanced bottoming cycle engines, and full 
electric vehicles are promoted in this first step through incentive 
concepts as discussed in Section IV, but we believe that these advanced 
technologies will not be necessary to meet the final standards. Today's 
standards are premised on the use of existing technologies given the 
short lead time, as discussed in Section III, below. When we begin work 
to develop a possible next set of regulatory standards, the agencies 
expect these advanced technologies to be an important part of the 
regulatory program and will consider them in setting the stringency of 
any standards beyond the 2018 model year.
    We will not only consider the progress of technology in our future 
regulatory efforts, but the agencies are also committed to fully 
considering a range of regulatory approaches. To more completely 
capture the complex interactions of the total vehicle and the potential 
to reduce fuel consumption and GHG emissions through the optimization 
of those interactions may require a more sophisticated approach to 
vehicle testing than we are adopting today for the largest heavy-duty 
vehicles. In future regulations, the agencies expect to fully evaluate 
the potential to expand the use of vehicle compliance models to reflect 
engine and drivetrain performance. Similarly, we intend to consider the 
potential for complete vehicle testing using a chassis dynamometer, not 
only as a means for compliance, but also as a complementary tool for 
the development of more complex vehicle modeling approaches. In 
considering these more comprehensive regulatory approaches, the 
agencies will also reevaluate whether separate regulation of trucks and 
engines remains necessary.
    In addition to technology and test procedures, vehicle and engine 
drive cycles are an important part of the overall approach to 
evaluating and improving vehicle performance. EPA, working through the 
WP.29 Global Technical Regulation process, has actively participated in 
the development of a new World Harmonized Duty Cycle for heavy-duty 
engines. EPA is committed to bringing forward these new procedures as 
part of our overall comprehensive approach for controlling

[[Page 57134]]

criteria pollutant and GHG emissions. However, we believe the important 
issues and technical work related to setting new criteria pollutant 
emissions standards appropriate for the World Harmonized Duty Cycle are 
significant and beyond the scope of this rulemaking. Therefore, the 
agencies are not adopting these test procedures in this action, but we 
are ready to work with interested stakeholders to adopt these 
procedures in a future action.
    As noted above, the agencies also intend to further investigate 
possibilities of expanded credit trading across the heavy-duty sector. 
As part of this effort, the agencies will investigate the degree to 
which the issue of credit trading is connected with complete vehicle 
testing procedures.
    As with this program, our future efforts will be based on 
collaborative outreach with the stakeholder community and will be 
focused on a program that delivers on our energy security and 
environmental goals without restricting the industry's ability to 
produce a very diverse range of vehicles serving a wide range of needs.

II. Final GHG and Fuel Consumption Standards for Heavy-Duty Engines and 
Vehicles

    This section describes the standards and implementation dates that 
the agencies are finalizing for the three categories of heavy-duty 
vehicles and engines. The agencies have performed a technology analysis 
to determine the level of standards that we believe will be cost-
effective, feasible, and appropriate in the lead time provided. This 
analysis, described in Section III and in more detail in the RIA 
Chapter 2, considered for each of the regulatory categories:
     The level of technology that is incorporated in current 
new engines and trucks,
     Forecasts of manufacturers' product redesign schedules,
     The available data on corresponding CO2 
emissions and fuel consumption for these engines and vehicles,
     Technologies that would reduce CO2 emissions 
and fuel consumption and that are judged to be feasible and appropriate 
for these vehicles and engines through the 2018 model year,
     The effectiveness and cost of these technologies, and
     Projections of future U.S. sales for trucks and engines.

A. What vehicles will be affected?

    EPA and NHTSA are finalizing standards for heavy-duty engines and 
also for what we refer to generally as ``heavy-duty vehicles.'' In 
general, these standards will apply for the model year 2014 and later 
engines and vehicles, although some standards do not apply until 2016 
or 2017. The EPA standards will apply throughout the useful life of the 
engine or vehicle, just as existing criteria emission standards apply 
throughout the useful life. As noted in Section I, for purposes of this 
preamble and rules, the term ``heavy-duty or ``HD'' applies to all 
highway vehicles and engines that are not regulated by the light-duty 
vehicle, light-duty truck and medium-duty passenger vehicle greenhouse 
gas and CAFE standards issued for MYs 2012-2016. Thus, in this notice, 
unless specified otherwise, the heavy-duty category incorporates all 
vehicles rated with GVWR greater than 8,500 pounds, and the engines 
that power these vehicles, except for MDPVs. The CAA defines heavy-duty 
vehicles as trucks, buses or other motor vehicles with GVWR exceeding 
6,000 pounds. See CAA section 202(b)(3). In the context of the CAA, the 
term HD as used in these final rules thus refers to a subset of these 
vehicles and engines. EISA section 103(a)(3) defines a `commercial 
medium- and heavy-duty on-highway vehicle' as an on-highway vehicle 
with GVWR of 10,000 pounds or more.\50\ EISA section 103(a)(6) defines 
a `work truck' as a vehicle that is rated at between 8,500 and 10,000 
pounds gross vehicle weight and is not a medium-duty passenger 
vehicle.\51\ Therefore, the term ``heavy-duty vehicles'' in this 
rulemaking refers to both work trucks and commercial medium- and heavy-
duty on-highway vehicles as defined by EISA. Heavy-duty engines 
affected by the standards are those that are installed in commercial 
medium- and heavy-duty vehicles, except for the engines installed in 
vehicles certified to a complete vehicle emissions standard based on a 
chassis test, which would be addressed as a part of those complete 
vehicles, and except for engines used exclusively for stationary power 
when the vehicle is parked. The agencies' scope is the same with the 
exception of recreational vehicles (or motor homes), as discussed 
above. The standards that EPA is finalizing today cover recreational 
on-highway vehicles, while NHTSA limited its scope in the proposal to 
not include these vehicles. See Section I.A above.
---------------------------------------------------------------------------

    \50\ Codified at 49 U.S.C. 32901(a)(7).
    \51\ EISA Section 103(a)(6) is codified at 49 U.S.C. 
32901(a)(19). EPA defines medium-duty passenger vehicles as any 
complete vehicle between 8,500 and 10,000 pounds GVWR designed 
primarily for the transportation of persons which meet the criteria 
outlined in 40 CFR 86.1803-01. The definition specifically excludes 
any vehicle that (1) has a capacity of more than 12 persons total 
or, (2) is designed to accommodate more than 9 persons in seating 
rearward of the driver's seat or, (3) has a cargo box (e.g., pickup 
box or bed) of six feet or more in interior length. (See the Tier 2 
final rulemaking, 65 FR 6698, February 10, 2000.)
---------------------------------------------------------------------------

    The NPRM did not include an export exclusion in NHTSA's fuel 
consumption standards. Oshkosh Corporation commented that NHTSA should 
add an export exclusion in order to accommodate the testing and 
delivery needs of manufacturers of vehicles intended for export. NHTSA 
agrees with this comment and Section 535.3 of the final rule specifies 
such an exclusion.
    EPA and NHTSA are finalizing standards for each of the following 
categories, which together comprise all heavy-duty vehicles and all 
engines used in such vehicles. In order to most appropriately regulate 
the broad range of heavy-duty vehicles and engines, the agencies are 
setting separate engine and vehicle standards for the combination 
tractors and Class 2b through 8 vocational vehicles. The engine 
standards and test procedures for engines installed in the tractors and 
vocational vehicles are discussed within the preamble sections for 
combination tractors and vocational vehicles, respectively. The 
agencies are establishing standards for heavy-duty pickups and vans 
that apply to the entire vehicle;--there are no separate engine 
standards.
    As discussed in Section IX, the agencies are not adopting GHG 
emission and fuel consumption standards for trailers at this time. In 
addition, the agencies are not adopting standards at this time for 
engine, chassis, and vehicle manufacturers which are small businesses 
(as defined by the Small Business Administration). More detailed 
discussion of each regulatory category is included in the subsequent 
sections below.

B. Class 7 and 8 Combination Tractors

    EPA is finalizing CO2 standards and NHTSA is finalizing 
fuel consumption standards for new Class 7 and 8 combination tractors. 
The standards are for the tractor cab, with a separate standard for the 
engine that is installed in the tractor. Together these standards would 
achieve reductions of up to 23 percent compared to the model 2010 
baseline level. As discussed below, EPA is finalizing its proposal to 
adopt the existing useful life definitions for Class 7 and 8 tractors 
and the heavy-duty engines installed in them. NHTSA and EPA are 
finalizing revised fuel consumption and GHG emissions standards for 
tractors, and finalizing as proposed engine standards for heavy-duty 
engines in Class 7 and 8 tractors. The agencies' analyses, as discussed

[[Page 57135]]

briefly below and in more detail later in this preamble and in the RIA 
Chapter 2, show that these standards are feasible and appropriate under 
each agency's respective statutory authorities.
    EPA is also finalizing standards to control N2O, 
CH4, and HFC emissions from Class 7 and 8 combination 
tractors. The final heavy-duty engine standards for both N2O 
and CH4 and details of the standard are included in the 
discussion in Section II.E.1.b and II.E.2.b, respectively. The final 
air conditioning leakage standards applying to tractor manufacturers to 
address HFC emissions are discussed in Section II.E.5.
    The agencies are finalizing CO2 emissions and fuel 
consumption standards for the combination tractors that reflect 
reductions that can be achieved through improvements in the tractor 
(such as aerodynamics), tires, and other vehicle systems. The agencies 
are also finalizing heavy-duty engine standards for CO2 
emissions and fuel consumption that reflect technological improvements 
in combustion and overall engine efficiency.
    The agencies have analyzed the feasibility of achieving the 
CO2 and fuel consumption standards, and have identified 
means of achieving the standards that are technically feasible in the 
lead time afforded, economically practicable and cost-effective. EPA 
and NHTSA present the estimated costs and benefits of the standards in 
Section III. In developing the final rules, the agencies have evaluated 
the kinds of technologies that could be utilized by engine and tractor 
manufacturers, as well as the associated costs for the industry and 
fuel savings for the consumer and the magnitude of the national 
CO2 and fuel savings that may be achieved.
    The agencies received comments from multiple stakeholders regarding 
the definition and classification of ``combination tractors.'' The 
commenters raised three key issues. First, EMA/TMA, Navistar and DTNA 
requested that both agencies use the same definition for ``tractor'' or 
``truck tractor'' in the final rules. EPA proposed a definition for 
``tractor'' in Sec.  1037.801 (see the proposed rule published November 
30, 2010, 75 FR 74402) which stated that ``tractor'' means a vehicle 
capable of pulling trailers that is not intended to carry significant 
cargo other than cargo in the trailer, or any other vehicle intended 
for the primary purpose of pulling a trailer. For purposes of this 
definition, the term ''cargo'' includes permanently attached equipment 
such as fire-fighting equipment. The following vehicles are tractors: 
any vehicle sold to an ultimate purchaser with a fifth wheel coupling 
installed; any vehicle sold to an ultimate purchaser with the rear 
portion of the frame exposed where the length of the exposed portion is 
5.0 meters or less. See Sec.  1037.620 for special provisions related 
to vehicles sold to secondary vehicle manufacturers in this condition. 
The following vehicles are not tractors: Any vehicle sold to an 
ultimate purchaser with an installed cargo carrying feature (for 
example, this would include dump trucks and cement trucks); any vehicle 
lacking a fifth wheel coupling sold to an ultimate purchaser with the 
rear portion of the frame exposed where the length of the exposed 
portion is more than 5.0 meters.
    NHTSA proposed to use the 49 CFR 571.3 definition of ``truck 
tractor'' in 49 CFR 535.4 (see the proposed rule published November 30, 
2010, 75 FR 74440) which stated that ``truck tractor'' means a truck 
designed primarily for drawing other motor vehicles and not so 
constructed as to carry a load other than a part of the weight of the 
vehicle and the load so drawn.
    Second, EMA/TMA, NTEA and Navistar expressed concerns over, and 
requested the removal of, the proposed language that all vehicles with 
sleeper cabs would be classified as tractors. The commenters argued 
that because there are vocational vehicles manufactured with sleeper 
cabs that operate as vocational vehicles and not as tractors, those 
vehicles should be treated the same as all other vocational vehicles. 
Third, eleven different commenters requested that the agencies 
subdivide tractors into line-haul tractors and vocational tractors and 
treat each based upon their operational characteristics: vocational 
tractors, which operate at lower speeds offroad or in stop-and-go city 
driving as vocational vehicles; and line-haul tractors, which operate 
at highway speeds on interstate roadways over long distances, as line-
haul tractors.
    In response to the first comment, the agencies have decided to 
standardize the definition of tractor by using the long-standing NHTSA 
definition of ``truck tractor'' established in 49 CFR 571.3. 49 CFR 
571.3(b) states that a ``truck tractor means a truck designed primarily 
for drawing other motor vehicles and not so constructed as to carry a 
load other than a part of the weight of the vehicle and the load so 
drawn.'' EPA's proposed definition for ``tractor'' in the NPRM was 
similar to the NHTSA definition, but included some additional language 
to require a fifth wheel coupling and an exposed frame in the rear of 
the vehicle where the length of the exposed portion is 5.0 meters or 
less. EMA and Navistar argued that these two different definitions 
could lead to confusion if the agencies applied their requirements for 
truck tractors differently from each other. The commenters suggested 
that the EPA definition was more complicated than necessary, and that 
the simpler NHTSA definition should be used by both agencies as the 
base definition of truck tractor.
    The agencies agree that the definitions should be standardized and 
that the NHTSA definition is sufficient and includes the essential 
requirement that a truck tractor is a truck designed ``primarily for 
drawing other motor vehicles and not so constructed as to carry a load 
other than a part of the weight of the vehicle and the load so drawn.'' 
EPA's proposed tractor definition was intended to be functionally 
equivalent to NHTSA's definition based on design, but to be more 
objective by including the criteria related to ``fifth wheels'' and 
exposed rear frame. However, EPA no longer believes that such 
additional criteria are needed for implementation. NHTSA established 
the definition for truck tractor in 49 CFR 571.3(b) years ago,\52\ and 
has not encountered any notable problems with its application. 
Nevertheless, because the NHTSA definition relies more on design intent 
than EPA's proposed definition, we recognize that there may be some 
questions regarding how the agencies would apply the NHTSA definition 
being finalized to certain unique vehicles. For example, many of the 
common automobile and boat transport trucks may look similar to 
tractors, but the agencies would not consider them to meet the 
definition, because they have the capability to carry one or several 
vehicles as cargo with or without a trailer attached, and therefore are 
not ``constructed as to carry a load other than a part of the weight of 
the vehicle and the load so drawn.'' Similarly, a ``dromedary'' style 
truck that has the capability to carry a large load of cargo with or 
without drawing a trailer would also not qualify as a tractor.\53\ Even 
though these particular vehicles identified could potentially draw 
other motor vehicles like a trailer, they have also been designed to 
carry cargo with or without the trailer attached. NHTSA has previously 
interpreted its definition for ``truck tractor'' as excluding these 
specific vehicles like the dromedary and

[[Page 57136]]

automobile/boat transport vehicles. Tow trucks have also been excluded 
from the category of truck tractor. On the other hand, it is worth 
clarifying that designs that allow cargo to be carried in the passenger 
compartment, the sleeper compartment, or external toolboxes would not 
exclude a vehicle from the tractor category. The agencies plan to 
continue with this approach for the HD fuel efficiency and GHG 
standards, which means that these particular vehicles will be subject 
to the vocational vehicle standards and not the tractor standards, but 
vehicles that did meet the definition above for ``tractor'' will be 
subject to the combination tractor standards.
---------------------------------------------------------------------------

    \52\ 33 FR 19703, December 25, 1968.
    \53\ A dromedary is a box, deck or plate mounted behind the cab 
to carry freight or cargo.
---------------------------------------------------------------------------

    In response to the second comment, the agencies have decided not to 
classify vocational vehicles with sleeper cabs as tractors. In the 
NPRM, the agencies proposed that vocational vehicles with sleeper cabs 
be classified as tractors out of concern that a vehicle could initially 
be manufactured as a straight truck vocational vehicle with a sleeper 
cab and, soon after introduction into commerce, be converted to a 
combination tractor as a means to circumvent the Class 8 sleeper cab 
regulations. Commenters who addressed this issue generally disagreed 
with the agencies' concern. EMA/TMA, for example, argued that it is 
expensive and difficult for a manufacturer to change a vehicle from a 
straight truck to a tractor, because of modifications required to the 
vehicle, such as to the vehicle's air brake system, and also because of 
the manufacturers ultimate responsibility for recertification to 
NHTSA's safety standards. EMA/TMA also argued that straight trucks are 
often built with sleeper cabs to perform the functions of a vocational 
type vehicle and not the functions of a line-haul tractor. NTEA also 
provided an example of a straight truck (Expediter Cab) that can be 
built with a sleeper cab and a cargo-carrying body, which it argued 
should be classified as a vocational vehicle and not a tractor.
    Upon further consideration, the agencies agree that vocational 
vehicles with sleeper cabs are more appropriately classified as 
vocational vehicles than as tractors. The comments discussed above help 
to illustrate the reasons for building a vocational vehicle with a 
sleeper cab and the difficulties of converting a straight truck to a 
tractor. Moreover, 49 U.S.C. Chapter 301 requires any service 
organization making such modifications to be responsible for 
recertification to all applicable Federal motor vehicle safety 
standards, which should act as a further deterrent to anyone 
contemplating making such a conversion. Together these two items 
address the agencies' primary reason for proposing the requirement that 
all vehicles with sleeper cabs be treated as tractors--the concern of 
circumvention of the tractor standards. However, the agencies will 
continue to monitor whether it appears that the definitions are 
creating unintended consequences, and may consider revising the 
definitions in a future rulemaking to address such issues should any 
arise. NHTSA and EPA have concluded that the engine and tire 
improvements required in the vocational category are appropriate for 
this set of vehicles based on the typical operation of these vehicles. 
The agencies did not intend to include vocational vehicles with sleeper 
cabs, such as an Expediter vehicle, into the tractor category in either 
the NPRM or in this final action, and the agencies' analyses at 
proposal reflected this intention. Therefore the agencies did not make 
any adjustments to the program costs and benefits due to this 
classification change.
    In response to the third comment, the agencies have decided to 
allow manufacturers to exclude certain vocational-type of tractors from 
the combination tractor standards and instead be subject to the 
vocational vehicle standards. We discuss below the reasoning underlying 
this decision, the criteria manufacturers would use in asserting a 
claim that a vocational tractor should be reclassified as a vocational 
vehicle, and the procedures the agencies will use to accept or reject 
manufacturers' claims.
    Multiple commenters (Allison Transmission, ATA, CALSTART, Eaton, 
EMA/TMA, National Solid Waste Management Association, MEMA, Navistar, 
NADA, RMA, and Volvo) argued that the agencies' proposed classification 
failed to recognize genuine differences between vocational tractors, 
which typically operate at lower speeds in stop-and-go city driving, 
and line-haul tractors, which typically operate at highway speeds on 
interstate roadways over long distances. Commenters argued that the 
proposed tractor standards and associated tractor GEM test cycles were 
derived based primarily upon the operational characteristics of the 
line-haul tractors, and that technologies that apply to these line-haul 
tractors, such as improved aerodynamics, vehicle speed limiters and 
automatic engine shutdown, as well as engine performance for improving 
emissions and fuel consumption, do not have the same positive impact on 
fuel consumption when used on tractors. In today's market, as mentioned 
by Volvo and ATA, we understand that approximately 15 percent, or 
approximately 15,000 to 20,000, of the Class 7 and 8 tractors could be 
classified as vocational tractors based upon the work they perform.
    The agencies agree that the overall operation of these vocational-
types of tractors resembles other vocational vehicles' operation: lower 
average speed and more stop and go activity than line-haul tractors. 
Due to their operation style, a FTP certified engine is a better match 
for these tractors than a SET certified engine, because the FTP cycle 
uses a lower average speed and more stop and go activity than the SET 
cycle. In addition, the limited high speed operation leads to minimal 
opportunities for fuel consumption and CO2 emissions 
reductions due to aerodynamic improvements. Conversely, the additional 
weight of the aerodynamic components could cause an unintended 
consequence of increasing gram per ton-mile emissions by reducing the 
amount of payload the vehicle can carry in those applications which are 
weight-limited. Similarly, the vocational tractors typically do not 
hotel overnight and therefore will have little to no benefit through 
the installation of an idle reduction technology.
    The agencies received several other comments that described 
criteria that could be used to distinguish between vocational and non-
vocational tractors. Volvo suggested that a tractor could be a 
vocational tractor if it meets three of five specified features:
    (1) A frame Resisting Bending Moment (RBM) greater than or equal to 
2,000,000 in-lbs per rail, or rail and liner combination;
    (2) An approach angle greater than or equal to 20 degrees nominal 
design specification, to exclude extended front rails/bumpers for 
additional equipment (e.g.--pumps, winch, front engine PTO);
    (3) Ground clearance greater than or equal to 14 inches as measured 
unladen from the lowest point of any frame rail or body mounted 
components, excluding axles and suspension (for HHD and MHD vehicles 
this is usually considered as the lowest point of the fuel tank/
mounting or chassis aerodynamic devices);
    (4) A total reduction in high gear greater than or equal to 3.00:1; 
and
    (5) A total reduction in low gear greater than or equal to 57:1.
    The approach proposed by Volvo is somewhat similar to the approach 
NHTSA has for determining if a vehicle is a light truck under the light 
vehicle CAFE program, in which a vehicle must either have a GVWR 
greater than 6,000 pounds or have 4-wheel drive, and meet

[[Page 57137]]

four of the five specified suspension characteristics (approach angle, 
break-over angle, axle clearance, etc.) to be classified as a light 
truck. Although we do not believe that the criteria suggested by Volvo 
are workable for all manufacturers and all applications, we agree that 
these criteria would reflect a reasonable basis for allowing 
manufacturers to reclassify their vehicles as vocational tractors.
    Two other commenters, EMA/TMA and Navistar, suggested simply that 
the manufacturer should have the burden of establishing that a tractor 
is a vocational tractor to the agencies' reasonable satisfaction. The 
commenters also suggested some factors that could be used to establish 
that a tractor is actually a ``vocational tractor'', including:
    (1) A vehicle speed limiter set at 55 mph or less;
    (2) Power take-off (PTO) controls;
    (3) Extended front frame;
    (4) Ground clearance greater than 14 in.;
    (5) An approach angle greater than 20 degrees;
    (6) Frame RBM greater than 2,000,000 in-lbs.; and
    (7) A total gear reduction in low gear greater than 57 and a total 
gear reduction in top gear greater than 3.
    The agencies believe that both suggested approaches have some 
merit. A rule based on specific criteria as suggested by Volvo could 
help to minimize the burden on both the manufacturers and the agencies, 
as manufacturer-written requests for approval and agency approvals of 
those requests would not be required for each vocational tractor 
determination whereas the EMA/TMA and Navistar approach requires the 
opposite namely that each manufacturer would have to justify the 
determination of each vocational tractor based upon its related design 
features in a separate petition to the agencies. Neither of the two 
approaches, which are based on specific criteria, could be used to 
identify all the tractors that should be classified as vocational 
tractors. An urban beverage delivery tractor, for example, may not be 
designed with any of the features mentioned but is used in a vocational 
vehicle manner. Also, the agencies were concerned about the possibility 
of manufacturers circumventing the system by incorporating design 
changes to their line-haul tractors in order to classify them as 
vocational tractors required to meet less stringent emission and fuel 
consumption standards. However, at this time the agencies do not 
believe that circumventing the system is likely, as most of these 
vocational tractors are built to order and will incorporate the design 
features required by the customer. Manufacturer vehicle offerings are 
designed or tailored to suit the particular task of the consumer. The 
vehicle transport mission including vehicle type, gross vehicle weight, 
gross combination weight, body style and load handling characteristics, 
must be considered in the design process. Further, how the vehicle will 
be utilized, including operating cycles, operating environment and road 
conditions, is another important consideration in designing a vehicle 
to accomplish a particular task. The agencies agree that these criteria 
could also be used as part of a basis for classification. We also note 
that many of these vehicles have front axle weight ratings greater than 
14,600 pounds.
    Although the agencies agree that these vocational tractors are 
operated differently than line-haul tractors and therefore fit more 
appropriately into the vocational vehicle category, we need to ensure 
that only tractors that are truly vocational tractors are classified as 
such. Upon further consideration of the comments received the agencies 
have decided to allow manufacturers to exclude certain vocational-type 
tractors from the combination tractor standards, and instead be subject 
to the standards for vocational vehicles. A vehicle determined by the 
manufacturer to be a HHD vocational tractor would fall into the HHD 
vocational vehicle subcategory and be regulated as a vocational 
vehicle. Similarly, MHD which the manufacturer chooses to reclassify as 
vocational tractors will be regulated as a MHD vocational vehicle. 
Specifically, under the provision being finalized at 40 CFR 1037.630 
and NHTSA's regulation at 49 CFR 523.2 of today's rules only the 
following three types of vocational tractors are eligible for 
reclassification by the manufacturer:
    (1) Low-roof tractors intended for intra-city pickup and delivery, 
such as those that deliver bottled beverages to retail stores.
    (2) Tractors intended for off-road operation (including mixed 
service operation), such as those with reinforced frames and increased 
ground clearance.
    (3) Tractors with a GCWR over 120,000 pounds.
    As adopted in 40 CFR 1037.230(a)(1)(xiii), manufacturers will be 
required to group vocational tractors into a unique family, separate 
from other combination tractors and vocational vehicles. The provision 
being adopted in 40 CFR 1037.630 and 49 CFR 535.8 requires the 
manufacturers to summarize in their applications their basis for 
believing that the vehicles are eligible for manufacturer 
reclassification as vocational tractors. EPA and NHTSA could ask for a 
more detailed description of the basis and EPA would deny an 
application for certification where it determines the manufacturer 
lacks an adequate basis for reclassification. The manufacturer would 
then have to resubmit a modified application to certify the vehicles in 
question to the tractor standards. Where we determine that a 
manufacturer is not applying this allowance in good faith, we may 
require that manufacturer to obtain preliminary approval before using 
this allowance. This would mean that a manufacturer would need to 
submit its detailed records to EPA and receive formal approval before 
submitting its application for certification. The agencies plan to 
monitor how manufacturers classify their tractor fleets and would 
reconsider the issue of vocational tractor classification in a future 
rulemaking if necessary.
    Because the difference between some vocational tractors and line-
haul tractors is potentially somewhat subjective, we are also including 
an annual sales limit of 7,000 vocational tractors per manufacturer 
(based on a three year rolling average) consistent with past production 
volumes of such vehicles. It is important to note, however, that we do 
not expect it to be common for manufacturers to be able to justify 
classifying 7,000 vehicles as vocational tractors in a given model 
year.
    Under the regulations being promulgated in 40 CFR 1037.630 and 49 
CFR 523.2, manufacturers will be required to keep records of how they 
determined that such vehicles qualify as vocational. These records 
would be more detailed than the description submitted in the 
applications. Typically, this would be a combination of records of the 
design features and/or purchasers of the vehicles. The agencies have 
analyzed the design features that reflect the special needs of these 
vocational tractors in the three areas noted above--mixed service, 
heavy haul, and urban delivery. Mixed service applications, such as 
construction trucks, typically require higher ground clearance and 
approach angle to accommodate non-paved roads. In addition, they often 
require frame rails with greater resisting bending moment (RBM) because 
of the terrain where they operate.\54\ The mixed service

[[Page 57138]]

applications also sometimes require higher front axle weight ratings to 
accommodate extra loads and/or power take off systems for additional 
capability. Heavy haul tractors are typically designed with frame rails 
with extra strength (greater RBM) and higher front axle weight ratings 
to accommodate the heavy payloads. Often the heavy haul tractors will 
also have higher ground clearance and greater approach angle for 
similar reasons as the mixed service applications. Lastly, heavy haul 
vehicles require a total gear reduction of 57:1 or greater to provide 
the torque necessary to start the vehicle moving. Urban delivery 
tractors, such as beverage haulers, have less defined design features 
that reflect their operational needs. These vehicles offer options 
which include high RBM rails and front axle weight ratings, but not all 
beverage trucks are specified with these options. The primary 
differentiation of these urban delivery tractors is their operation. 
For this final rulemaking, the agencies projected the costs and 
benefits of the program considering this provision. As detailed in RIA 
Section 5.3.2.2.1, the agencies assumed that approximately 20 percent 
of short-haul tractors sold in 2014 model year and beyond will be 
vocational tractors. As such, these vehicles will experience benefits 
reflective of a FTP-certified engine and tire rolling resistance 
improvement at the technology costs projected in the rules for 
vocational vehicles.
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    \54\ The agencies have found based on standard truck 
specifications, that vehicles designed for significant off-road 
applications, such as concrete pumper and logging trucks have 
resisting bending moment greater than 2,100,000 lb-in. (ranging up 
to 3,580,000 lb-in.). The typical on highway tractors have resisting 
bending moment of 1,390,000 lb-in. An example line haul truck is the 
Mack Pinnacle which has a RBM of 1,390,000 lb-in, as shown at http://www.macktrucks.com/assets/MackMarketing/Specifications/CXU6124x2PinAxleBack.pdf.
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(1) What is the form of the Class 7 and 8 tractor CO2 
emissions and fuel consumption standards?
    As proposed, EPA and NHTSA are finalizing different standards for 
different subcategories of these tractors with the basis for 
subcategorization being particular tractor attributes. Attribute-based 
standards in general recognize the variety of functions performed by 
vehicles and engines, which in turn can affect the kind of technology 
that is available to control emissions and reduce fuel consumption, or 
its effectiveness. Attributes that characterize differences in the 
design of vehicles, as well as differences in how the vehicles will be 
employed in-use, can be key factors in evaluating technological 
improvements for reducing CO2 emissions and fuel 
consumption. Developing an appropriate attribute-based standard can 
also avoid interfering with the ability of the market to offer a 
variety of products to meet consumer demand. There are several examples 
of where the agencies have utilized an attribute-based standard. In 
addition to the example of the light-duty 2012-16 MY vehicle rule, in 
which the standards are based on the attribute of vehicle 
``footprint,'' the existing heavy-duty highway engine standards for 
criteria pollutants have for many years been based on a vehicle weight 
attribute (Light Heavy, Medium Heavy, Heavy Heavy) with different 
useful life periods, which is a similar approach finalized for the 
engine GHG and fuel consumption standards discussed below.
    Heavy-duty combination tractors are built to move freight. The 
ability of a vehicle to meet a customer's freight transportation 
requirements depends on three major characteristics of the tractor: the 
gross vehicle weight rating (which along with gross combination weight 
rating (GCWR) establishes the maximum carrying capacity of the tractor 
and trailer), cab type (sleeper cabs provide overnight accommodations 
for drivers), and the tractor roof height (to mate tractors to trailers 
for the most fuel-efficient configuration). Each of these attributes 
impacts the baseline fuel consumption and GHG emissions, as well as the 
effectiveness of possible technologies, like aerodynamics, and is 
discussed in more detail below.
    The first tractor characteristic to consider is payload which is 
determined by a tractor's GVWR and GCWR relative to the weight of the 
tractor, trailer, fuel, driver, and equipment. Class 7 trucks, which 
have a GVWR of 26,001-33,000 pounds and a typical GCWR of 65,000 
pounds, have a lesser payload capacity than Class 8 trucks. Class 8 
trucks have a GVWR of greater than 33,000 pounds and a typical GCWR of 
greater than 80,000 pounds, the effective weight limit on the federal 
highway system except in states with preexisting higher weight limits. 
Consistent with the recommendation in the National Academy of Sciences 
2010 Report to NHTSA,\55\ the agencies are finalizing a load-specific 
fuel consumption metric (g/ton-mile and gal/1,000 ton-mile) where the 
``ton'' represents the amount of payload. Generally, higher payload 
capacity vehicles have better specific fuel consumption and GHG 
emissions than lower payload capacity vehicles. Therefore, since the 
amount of payload that a Class 7 vehicle can carry is less than the 
Class 8 vehicle's payload capacity, the baseline fuel consumption and 
GHG emissions performance per ton-mile differs between the categories. 
It is consequently reasonable to distinguish between these two vehicle 
categories, so that the agencies are finalizing separate standards for 
Class 7 and Class 8 tractors.
---------------------------------------------------------------------------

    \55\ See 2010 NAS Report, Note 21, Recommendation 2-1.
---------------------------------------------------------------------------

    The agencies are not finalizing a single standard for both Class 7 
and 8 tractors based on the payload carrying capabilities and assumed 
typical payload levels of Class 8 tractors alone, as that would quite 
likely have the perverse impact of increasing fuel consumption and 
greenhouse gas emissions. Such a single standard would penalize Class 7 
vehicles in favor of Class 8 vehicles. However, the greater 
capabilities of Class 8 tractors and their related greater efficiency 
when measured on a per ton-mile basis are only relevant in the context 
of operations where that greater capacity is needed. For many 
applications such as regional distribution, the trailer payloads 
dictated by the goods being carried are lower than the average Class 8 
tractor payload. In those situations, Class 7 tractors are more 
efficient than Class 8 tractors when measured by ton-mile of actual 
freight carried. This is because the extra capabilities of Class 8 
tractors add additional weight to vehicles that is only beneficial in 
the context of its higher capabilities. The existing market already 
selects for vehicle performance based on the projected payloads. By 
setting separate standards the agencies do not advantage or 
disadvantage Class 7 or 8 tractors relative to one another and continue 
to allow trucking fleets to purchase the vehicle most appropriate to 
their business practices.
    The second characteristic that affects fuel consumption and GHG 
emissions is the relationship between the tractor cab roof height and 
the type of trailer used to carry the freight. The primary trailer 
types are box, flat bed, tanker, bulk carrier, chassis, and low boys. 
Tractor manufacturers sell tractors in three roof heights--low, mid, 
and high. The manufacturers do this to obtain the best aerodynamic 
performance of a tractor-trailer combination, resulting in reductions 
of GHG emissions and fuel consumption, because it allows the frontal 
area of the tractor to be similar in size to the frontal area of the 
trailer. In other words, high roof tractors are designed to be paired 
with a (relatively tall) box trailer while a low roof tractor is 
designed to pull a (relatively low) flat bed trailer. The baseline 
performance of

[[Page 57139]]

a high roof, mid roof, and low roof tractor differs due to the 
variation in frontal area which determines the aerodynamic drag. For 
example, the frontal area of a low roof tractor is approximately 6 
square meters, while a high roof tractor has a frontal area of 
approximately 9.8 square meters. Therefore, as explained below, the 
agencies are using the roof height of the tractor to determine the 
trailer type required to be used to demonstrate compliance of a vehicle 
with the fuel consumption and CO2 emissions standards. As 
with vehicle weight classes, setting separate standards for each 
tractor roof height helps ensure that all tractors are regulated to 
achieve appropriate improvements, without inadvertently leading to 
increased emissions and fuel consumption by shifting the mix of vehicle 
roof heights offered in the market away from a level determined by 
market foces linked to the actual trailers vehicles will haul in-use.
    Tractor cabs typically can be divided into two configurations--day 
cabs and sleeper cabs. Line haul operations typically require overnight 
accommodations due to Federal Motor Carrier Safety Administration hours 
of operation requirements.\56\ Therefore, some truck buyers purchase 
tractor cabs with sleeping accommodations, also known as sleeper cabs, 
because they do not return to their home base nightly. Sleeper cabs 
tend to have a greater empty curb weight than day cabs due to the 
larger cab volume and accommodations, which lead to a higher baseline 
fuel consumption for sleeper cabs when compared to day cabs. In 
addition, there are specific technologies, such as extended idle 
reduction technologies, which are appropriate only for tractors which 
hotel--such as sleeper cabs. To respect these differences, the agencies 
are finalizing separate standards for sleeper cabs and day cabs.\57\
---------------------------------------------------------------------------

    \56\ The Federal Motor Carrier Safety Administration's Hours-of-
Service regulations put limits in place for when and how long 
commercial motor vehicle drivers may drive. They are based on an 
exhaustive scientific review and are designed to ensure truck 
drivers get the necessary rest to perform safe operations. See 49 
CFR part 395, and see also http://www.fmcsa.dot.gov/rules-regulations/topics/hos/index.htm (last accessed August 8, 2010).
    \57\ The agencies note, as discussed in the previous section, 
that some day cabs and sleeper cabs will be reclassified as 
vocational tractors and if so will not be subject to the combination 
tractor standards.
---------------------------------------------------------------------------

    The agencies received comments from industry stakeholders (EMA, 
Allison Transmission, Bosch, and the Heavy-Duty Fuel Efficiency 
Leadership Group) and ICCT supporting the nine tractor regulatory 
subcategories proposed and did not receive any comments which supported 
an alternate classification. Thus, to account for the relevant 
combinations of these attributes, the agencies are adopting the 
classification scheme proposed, segmenting combination tractors into 
the following nine regulatory subcategories:
     Class 7 Day Cab With Low Roof
     Class 7 Day Cab With Mid Roof
     Class 7 Day Cab With High Roof
     Class 8 Day Cab With Low Roof
     Class 8 Day Cab With Mid Roof
     Class 8 Day Cab With High Roof
     Class 8 Sleeper Cab With Low Roof
     Class 8 Sleeper Cab With Mid Roof
     Class 8 Sleeper Cab With High Roof
    Adjustable roof fairings are used today on what the agencies 
consider to be low roof tractors. The adjustable fairings allow the 
operator to change the fairing height to better match the type of 
trailer that is being pulled which can reduce fuel consumption and GHG 
emissions during operation. As proposed, the agencies are treating 
tractors with adjustable roof fairings as low roof tractors that will 
tested with the fairing in its lowest position.
(2) What are the Final Class 7 and 8 Tractor and Engine CO2 
Emissions and Fuel Consumption Standards and Their Timing?
    In developing the final standards for Class 7 and 8 tractors and 
for the engines used in these tractors, the agencies have evaluated the 
current levels of emissions and fuel consumption, the kinds of 
technologies that could be utilized by truck and engine manufacturers 
to reduce emissions and fuel consumption from tractors and associated 
engines, the necessary lead time, the associated costs for the 
industry, fuel savings for the consumer, and the magnitude of the 
CO2 and fuel savings that may be achieved. The technologies 
on whose performance the final tractor standards are predicated are 
improvements in aerodynamic design, lower rolling resistance tires, 
extended idle reduction technologies, and lightweighting of the 
tractor. The technologies on whose performance the final tractor 
standards are predicated are engine friction reduction, aftertreatment 
optimization, and turbocompounding, among others, as described in RIA 
Chapter 2.4. The agencies' evaluation showed that these technologies 
are available today, but have very low application rates on current 
vehicles and engines. EPA and NHTSA also present the estimated costs 
and benefits of the Class 7 and 8 combination tractor and engine 
standards in Section III and in RIA Chapter 2, explaining as well the 
basis for the agencies' conclusion not to adopt standards which are 
less stringent or more stringent.
(a) Tractor Standards
    The agencies are finalizing the following standards for Class 7 and 
8 combination tractors in Table 0-1, using the subcategorization 
approach that was proposed. As explained below in Section III, EPA has 
determined that there is sufficient lead time to introduce various 
tractor and engine technologies into the fleet starting in the 2014 
model year, and is finalizing standards starting for that model year 
predicated on performance of those technologies. EPA is finalizing more 
stringent tractor standards for the 2017 model year which reflect the 
CO2 emissions reductions required for 2017 model year 
engines. (As explained in Section II.B(3)(h)(v) below, engine 
performance is one of the inputs into the compliance model, and that 
input will change in 2017 to reflect the 2017 MY engine standards.) The 
2017 MY vehicle standards are not premised on tractor manufacturers 
installing additional vehicle technologies. EPA's final standards apply 
throughout the useful life period as described in Section V. As 
proposed, and as discussed further in Section IV below, manufacturers 
may generate and use credits from Class 7 and 8 combination tractors to 
show compliance with the standards.
    NHTSA is finalizing Class 7 and 8 tractor fuel consumption 
standards that are voluntary standards in the 2014 and 2015 model years 
and become mandatory beginning in the 2016 model year, as required by 
the lead time within EISA. The 2014 and 2015 model year standards are 
voluntary in that manufacturers are not subject to them unless they 
opt-in to the standards.\58\ Manufacturers that opt in become subject 
to NHTSA standards for all regulatory categories. NHTSA is also 
adopting new tractor standards for the 2017 model year which reflect 
additional improvements in only the heavy-duty engines. As proposed, 
NHTSA is not implementing an in-use compliance program for fuel 
consumption because it does not anticipate that there will be notable 
deterioration of fuel consumption over the useful life of the vehicle.
---------------------------------------------------------------------------

    \58\ Once a manufacturer opts into the NHTSA program it must 
stay in the program for all the optional MYs.
---------------------------------------------------------------------------

    As explained more fully in Section III and Chapter 2 of the RIA, 
EPA and NHTSA are not adopting more stringent tractor standards for 
2014-2017 MY. The final tractor standards are based on

[[Page 57140]]

the maximum application rates of available technologies considering the 
available lead time, and we explain in Section III and Chapter 2 of the 
RIA that use of additional technologies, or further application of the 
technologies already mentioned would be either infeasible in the lead 
time afforded, or uneconomic.

               Table II-1--Heavy-Duty Combination Tractor Emissions and Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
                                                                      Day cab                     Sleeper cab
                                                     -----------------------------------------------------------
                                                            Class 7             Class 8             Class 8
----------------------------------------------------------------------------------------------------------------
                                     2014 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof............................................                 107                  81                  68
Mid Roof............................................                 119                  88                  76
High Roof...........................................                 124                  92                  75
----------------------------------------------------------------------------------------------------------------
                          2014-2016 Model Year Gallons of Fuel per 1,000 Ton-Mile \59\
----------------------------------------------------------------------------------------------------------------
Low Roof............................................                10.5                 8.0                 6.7
Mid Roof............................................                11.7                 8.7                 7.4
High Roof...........................................                12.2                 9.0                 7.3
----------------------------------------------------------------------------------------------------------------
                                     2017 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof............................................                 104                  80                  66
Mid Roof............................................                 115                  86                  73
High Roof...........................................                 120                  89                  72
----------------------------------------------------------------------------------------------------------------
                          2017 Model Year and Later Gallons of Fuel per 1,000 Ton-Mile
----------------------------------------------------------------------------------------------------------------
Low Roof............................................                10.2                 7.8                 6.5
Mid Roof............................................                11.3                 8.4                 7.2
High Roof...........................................                11.8                 8.7                 7.1
----------------------------------------------------------------------------------------------------------------

    The standard values shown above differ somewhat from the proposal, 
reflecting refinements made to the GEM in response to comments. For 
example, the agencies received comments from stakeholders concerned 
that the 2017 MY tractor standards appeared to be backsliding because 
the reductions were not in line with the reductions expected from the 
2017 MY engine standards. The agencies reviewed the issue and found 
that the engine maps we created in the GEM for the 2017 model year for 
the proposal did not appropriately reflect the engine improvements. 
Therefore, the agencies developed new fuel maps for the GEM v2.0 which 
fully reflect the engine improvements due to the 2017 MY standards.\60\ 
These changes to the GEM did not impact our estimates of the relative 
effectiveness of the greenhouse gas emissions and fuel consumption 
improving technologies modeled in this final action nor the overall 
cost or benefits estimated for these final vehicle standards.
---------------------------------------------------------------------------

    \59\ As noted above, manufacturers may voluntarily opt-in to the 
NHTSA fuel consumption program in 2014 or 2015. Once a manufacturer 
opts into the NHTSA program it must stay in the program for all the 
optional MYs.
    \60\ See RIA Chapter 4 for the engine fuel maps used in GEM 
v2.0.
---------------------------------------------------------------------------

    Based on our analysis, the 2017 model year standards for 
combination tractors and engines represent up to a 23 percent reduction 
in CO2 emissions and fuel consumption over a 2010 model year 
baseline tractor (the baseline sleeper cab does not include idle 
shutdown technology), as detailed in Section III.A.2. In considering 
the feasibility of vehicles to comply with the standards, EPA also 
considered the potential for CO2 emissions to increase 
during the regulatory useful life of the product. As we discuss 
separately in the context of deterioration factor (DF) testing, we have 
concluded that CO2 emissions are likely to stay the same or 
actually decrease in-use compared to new certified configurations. In 
general, engine and vehicle friction decreases as products wear in 
leading to reduced parasitic losses and lower CO2 emissions. 
Similarly, tire rolling resistance falls as tires wear due to the 
reduction in tread height. In the case of aerodynamic components, we 
project no change in performance through the regulatory life of the 
vehicle since there is essentially no change in their physical form as 
vehicles age. Similarly, weight reduction elements such as aluminum 
wheels are not projected to increase in mass through time, and hence, 
we can conclude will not deteriorate with regard to CO2 
performance in-use. Given all of these considerations, EPA is confident 
in projecting that the standards finalized today will be technical 
feasible throughout the regulatory useful life of the program.
(b) Standards for Engines Installed in Combination Tractors
    EPA is adopting GHG standards and NHTSA is adopting fuel 
consumption standards for new heavy-duty engines. This section 
discusses the standards for engines used in Class 7 and 8 combination 
tractors and also provides some overall background information. We also 
note that the agencies are adopting standards for heavy-duty engines 
used in vocational vehicles. However, as explained further below, 
compliance with the standards would be measured using different test 
procedures, corresponding with actual vehicle use, depending on whether 
the vehicle in which the engine is installed is a Class 7 and 8 
combination tractor or a vocational vehicle.
    The heavy-duty engine standards vary depending on the type of 
vehicle in which they are installed, as well as whether the engines are 
compression ignition or spark ignition. The agencies are adopting 
separate engine fuel consumption and GHG emissions standards for 
engines installed in combination tractors versus engines installed in 
vocational vehicles. Also, for the purposes of the GHG engine emissions 
and engine fuel consumption standards, the agencies are adopting engine 
subcategories that match EPA's

[[Page 57141]]

existing criteria pollutant emissions regulations for heavy-duty 
highway engines which established four regulatory service classes that 
represent the engine's intended and primary vehicle application.\61\ 
The Light Heavy-Duty (LHD) diesel engines are intended for application 
in Class 2b through Class 5 trucks (8,501 through 19,500 pounds GVWR). 
The Medium Heavy-Duty (MHD) diesel engines are intended for Class 6 and 
Class 7 trucks (19,501 through 33,000 pounds GVWR). The Heavy Heavy-
Duty (HDD) diesel engines are primarily used in Class 8 trucks (33,001 
pounds and greater GVWR). Lastly, spark ignition engines (primarily 
gasoline-powered engines) installed in incomplete vehicles less than 
14,000 pounds GVWR and spark ignition engines that are installed in all 
vehicles (complete or incomplete) greater than 14,000 pounds GVWR are 
grouped into a single engine service class. The engines in these four 
regulatory service classes range in size between approximately five 
liters and sixteen liters. This subcategory structure enables the 
agencies to set standards that appropriately reflect the technology 
available for engines installed in each type of vehicle, and that are 
therefore technologically feasible for these engines. This is the same 
engine classification scheme the agencies proposed, and there were no 
adverse comments in response to the proposal.
---------------------------------------------------------------------------

    \61\ See 40 CFR 86.90-2.
---------------------------------------------------------------------------

    Heavy heavy-duty diesel and medium heavy-duty diesel engines are 
used today in combination tractors. The following section refers to the 
engine standards for these types of engines. This section does not 
cover gasoline or light heavy-duty diesel engines because they are not 
used in combination tractors.
    In the NPRM, the agencies proposed CO2 and fuel 
consumption standards for HD diesel engines to be installed in Class 7 
and 8 combination tractors as shown in Table II-2.\62\
---------------------------------------------------------------------------

    \62\ The agencies note that the CO2 and fuel 
consumption standards for Class 7 and 8 combination tractors do not 
cover gasoline or LHDD engines, as those are not used in Class 7 and 
8 combination tractors.

            Table II-2--Proposed Heavy-duty Diesel Engine Standards for Engines Installed in Tractors
----------------------------------------------------------------------------------------------------------------
                                                     Effective 2014 model year       Effective 2017 Model Year
                                                 ---------------------------------------------------------------
                                                                  Voluntary fuel                       Fuel
                                                   CO2 standard     consumption    CO2 standard     consumption
                                                    (g/bhp-hr)    standard  (gal/   (g/bhp-hr)    standard  (gal/
                                                                    100 bhp-hr)                     100 bhp-hr)
----------------------------------------------------------------------------------------------------------------
MHD diesel engine...............................             502            4.93             487            4.78
HHD diesel engine...............................             475            4.67             460            4.52
----------------------------------------------------------------------------------------------------------------

    The agencies proposed to require diesel engine manufacturers to 
achieve, on average, a three percent reduction in fuel consumption and 
CO2 emissions for the 2014 standards over the baseline MY 
2010 performance for the engines.\63\ The agencies' preliminary 
assessment of the findings of the 2010 NAS Report and other literature 
sources indicated that there are technologies available to reduce fuel 
consumption by this amount in the time frame in the lead time provided 
by the rules. These technologies include improved turbochargers, 
aftertreatment optimization, and low temperature exhaust gas 
recirculation.
---------------------------------------------------------------------------

    \63\ The baseline HHD diesel engine performance in MY 2010 on 
the SET is 490 g CO2/bhp-hr (4.81 gal/100 bhp-hr), as 
determined from confidential data provided by manufacturers and data 
submitted for the non-GHG emissions certification process. The 
baseline MHD diesel engine performance on the SET cycle is 518 g 
CO2/bhp-hr (5.09 gallon/100-bhp-hr) in MY 2010. Further 
discussion of the derivation of the baseline can be found in Section 
III.
---------------------------------------------------------------------------

    The agencies also proposed to require diesel engine manufacturers 
to achieve, on average, a six percent reduction in fuel consumption and 
CO2 emissions for the 2017 MY standards over the baseline MY 
2010 performance for MHD and HHD diesel engines required to use the 
SET-based standard. The agencies stated that additional reductions 
could likely be achieved through the increased refinement of the 
technologies projected to be implemented for 2014, plus the addition of 
turbocompounding, which the agencies' analysis showed would require a 
longer development time and would not be available in MY 2014. The 
agencies therefore proposed to provide additional lead time to allow 
for the introduction of this additional technology, and to wait until 
2017 to increase stringency to levels reflecting application of this 
technology.
    The agencies proposed that the MHD and HHD diesel engine 
CO2 standards for Class 7 and 8 combination tractors would 
become effective in MY 2014 for EPA, with more stringent CO2 
standards becoming effective in MY 2017, while NHTSA's fuel consumption 
standards would become effective in MY 2017, which would be both 
consistent with the EISA four-year minimum lead-time requirements and 
harmonized with EPA's timing. The agencies explained that the three-
year timing, besides being required by EISA, made sense because EPA's 
heavy-duty highway engine program for criteria pollutants had begun to 
provide new emissions standards for the industry in three year 
increments, which had caused the heavy-duty engine product plans to 
fall largely into three year cycles reflecting this regulatory 
environment. To further harmonize with EPA, NHTSA proposed voluntary 
fuel consumption standards for MHD and HHD diesel engines that are 
equivalent to EPA CO2 standards for MYs 2014-2016, allowing 
manufacturers to opt into the voluntary standards in any of those model 
years.\64\ NHTSA proposed that manufacturers could opt into the program 
by declaring their intent to opt in to the program at the same time 
they submit the Pre-Certification Compliance Report, and that a 
manufacturer opting into the program would begin tracking credits and 
debits beginning in the model year in which they opt into the program. 
Both agencies proposed to allow manufacturers to generate and use 
credits to achieve compliance with the HD diesel engine standards, 
including averaging, banking, and trading (ABT) and deficit carry-
forward. The agencies sought comment on the proposed MHD and HHD engine 
standards and timing.
---------------------------------------------------------------------------

    \64\ Once a manufacturer opts into the NHTSA program it must 
stay in the program for all the optional MYs and remain standardized 
with the implementation approach being used to meet the EPA emission 
program.
---------------------------------------------------------------------------

    The agencies received comments from EMA, Navistar, Cummins, ACEEE, 
Center for Biological Diversity, Detroit Diesel Corporation, American 
Lung Association, and the Union of

[[Page 57142]]

Concerned Scientists. Comments were divided with respect to the 
proposed levels of stringency. While Cummins and DDC expressed support 
for the CO2 and fuel consumption standards for diesel 
engines, and EMA and Navistar stated the standards could be met if the 
flexibilities outlined in the NPRM are finalized as proposed, Navistar 
also stated that the model year 2017 standard may not be feasible since 
what the agencies characterized as existing technologies are not in 
production for all manufacturers. In contrast, environmental groups and 
NGOs stated that the standards did not reflect the potential reductions 
outlined in the 2010 NAS study and should be more stringent. CBD argued 
that the standards were not set at the maximum feasible level by 
definition, because the agencies had said that they were based on the 
use of existing technologies. In addition, the Center for Neighborhood 
Technology encouraged the agencies to implement the rules as soon as 
possible, beginning in the 2012 model year.
    In light of the above comments, the agencies re-evaluated the 
technical basis for the heavy-duty engine standards. The baseline HHD 
diesel engine performance in 2010 model year on the SET is estimated at 
490 g CO2/bhp-hr (4.81 gal/100 bhp-hr), based on our 
analysis of confidential data provided by manufacturers and data 
submitted for the non-GHG emissions certification process. Similarly, 
the baseline MHD diesel engine performance on the SET cycle is 
estimated to be 518 g CO2/bhp-hr (5.09 gallon/100-bhp-hr) 
for the 2010 model year. Further discussion of the derivation of the 
baseline can be found in Section III. The agencies believe that the MY 
2014 standards can be achieved by most manufacturers through the use of 
technologies time frame such as improved aftertreatment systems, 
friction reduction, improved auxiliaries, turbochargers, pistons, and 
other components. These standards will require diesel engine 
manufacturers to achieve on average a three percent reduction in fuel 
consumption and CO2 emissions over the baseline 2010 model 
year levels.
    However, in recognizing that some manufacturers have engines that 
would not meet the standard even after applying technologies that 
improve GHG emissions and fuel consumption by three percent, the 
agencies are finalizing both the proposed ABT provisions for these 
engines and also an optional alternate engine standard for 2014 model 
year, described in more detail below. We believe that concerns 
expressed by Navistar regarding the 2014 MY standards will be addressed 
by this alternative standard. The agencies also continue to believe 
that the 2017 MY standards are achievable using the above approaches 
and, in the case of SET certified engines, turbocompounding. While 
Navistar commented that the 2017 MY standard may be challenging because 
not all manufacturers are presently producing the technologies that may 
be required to meet the standards, the agencies believe that since 
manufacturers that may require turbocompounding to meet the standards 
will not have to do so until 2017 MY, there will be sufficient lead 
time for all manufacturers to introduce this technology. As noted 
above, by MY 2017 all MHD and HHD engines installed in combination 
tractors should have gone through a redesign during which all needed 
technology can be applied. We note that we are finalizing these 
standards as proposed based on the assessment that most manufacturers 
(not just Navistar) will need to make improvements to existing engine 
systems in order to meet the standards. EPA's HD diesel engine 
CO2 emission standards and NHTSA's HD diesel engine fuel 
consumption standards for engines installed in tractors are presented 
in Table II-3. As explained above, the first set of standards take 
effect with MY 2014 (mandatory standards for EPA, voluntary standards 
for NHTSA), and the second set take effect with MY 2017 (mandatory for 
both agencies).

             Table II-3--Final Heavy-duty Diesel Engine Standards for Engines Installed in Tractors
----------------------------------------------------------------------------------------------------------------
                                                     Effective 2014 model year       Effective 2017 model year
                                                 ---------------------------------------------------------------
                                                                  Voluntary fuel                       Fuel
                                                   CO2 standard     consumption    CO2 standard     consumption
                                                    (g/bhp-hr)    standard  (gal/   (g/bhp-hr)    standard  (gal/
                                                                    100 bhp-hr)                     100 bhp-hr)
----------------------------------------------------------------------------------------------------------------
MHD diesel engine...............................             502            4.93             487            4.78
HHD diesel engine...............................             475            4.67             460            4.52
----------------------------------------------------------------------------------------------------------------

    The agencies have also decided to remove NHTSA's proposed Pre-
Certification Compliance Report requirement. Instead, manufacturers 
must submit their decision to opt into NHTSA's voluntary standards for 
the 2014 through 2016 model years as part of its certification process 
with EPA. Once a manufacturer opts into the NHTSA program it must stay 
in the program for all the subsequent optional model years. 
Manufacturers that opt in become subject to NHTSA standards for all 
regulatory categories. The declaration statement must be entered prior 
to or at the same time the manufacturer submits its first application 
for a certificate of conformity. NHTSA will begin tracking credits and 
debits beginning in the model year in which a manufacturer opts into 
its program.
    Compliance with the CO2 emissions and fuel consumption 
standards will be evaluated based on the SET engine test cycle. In the 
NPRM, the agencies proposed standards based on the SET cycle for MHD 
and HHD engines used in tractors due to these engines' primary use in 
steady state operating conditions (typified by highway cruising). 
Tractors spend the majority of their operation at steady state 
conditions, and will obtain in-use benefit of technologies such as 
turbocompounding and other waste heat recovery technologies during this 
kind of typical engine operation. Therefore, the engines installed in 
tractors will be required to meet the standard based on the SET, which 
is a steady state test cycle.
    The agencies gave full consideration to the need for engine 
manufacturers to redesign and upgrade their engines during the MYs 
2014-2017 to meet standards, and fully considered the cost-
effectiveness of the standards and the available lead time. The final 
two-step CO2 emission and fuel consumption standards 
recognize the opportunity for technology improvements over the 
rulemaking time frame, while reflecting the typical engine 
manufacturers' product plan cycles. Over these four model years there 
will be an opportunity for manufacturers to evaluate almost every one 
of their

[[Page 57143]]

engine models and add technology in a cost-effective way, consistent 
with existing redesign schedules, to control GHG emissions and reduce 
fuel consumption. The time-frame and levels for the standards, as well 
as the ability to average, bank and trade credits and carry a deficit 
forward for a limited time, are expected to provide manufacturers the 
time and flexibilities needed to incorporate technology that will 
achieve the final GHG and fuel consumption standards within the normal 
engine redesign process. This is an important aspect of the final 
rules, as it will avoid the much higher costs that would occur if 
manufacturers needed to add or change technology at times other than 
these scheduled redesigns.\65\ This time period will also provide 
manufacturers the opportunity to plan for compliance using a multi-year 
time frame, again in alignment with their normal business practice. 
Further details on lead time, redesigns and technical feasibility can 
be found in Section III.
---------------------------------------------------------------------------

    \65\ See 75 FR at 25467-68 for further discussion of the 
negative cost implications of establishing requirements outside of 
the redesign cycle.
---------------------------------------------------------------------------

    The agencies continue to believe the standards for MHD and HHD 
diesel engines installed in combination tractors are the most stringent 
technically feasible in the time frame established in this regulation. 
The standards will require a 3 percent reduction in engine fuel 
consumption and GHG emissions in 2014 MY based on improvements to 
engine components and aftertreatment systems. The 2017 MY standards 
will require a 6 percent reduction in fuel consumption and GHG 
emissions over a 2010 model year baseline and assumes the introduction, 
for some engines, of technologies such as turbocompounding. The 
standards, however, are not premised on the introduction of 
technologies that are still in development--such as Rankine bottoming 
cycle--since these approaches cannot be introduced without further 
technical development or engine re-design.\66\
---------------------------------------------------------------------------

    \66\ See RIA Chapter 2.4.2.7.
---------------------------------------------------------------------------

    Additional discussion on technical feasibility is included in 
Section III below and in Chapter 2 of the RIA.
    The agencies recognize, however, that the schedule of changes for 
the final standards may not be the most cost-effective one for all 
manufacturers. The agencies also sought comment as to whether an 
alternate phase-in schedule for the HD diesel engine standards for 
combination tractors should be considered. In developing the proposal, 
heavy-duty engine manufacturers stated that the phase-in of the GHG and 
fuel consumption standards should be aligned with the On Board 
Diagnostic (OBD)\67\ phase-in schedule, which includes new requirements 
for heavy-duty vehicles in the 2013 and 2016 model years. The agencies 
did not adopt this suggestion in the proposal, explaining that the 
credit averaging, banking and trading provisions would provide 
manufacturers with considerable flexibility to manage their GHG and 
fuel efficiency standard compliance plans--including the phase-in of 
the new heavy-duty OBD requirements--but requested comment on whether 
EPA and NHTSA should provide an alternate phase-in schedules that would 
more explicitly accommodate this request in the event that 
manufacturers did not agree that the ABT provisions mitigated their 
concern about the GHG/fuel consumption standard phase-in. See 75 FR at 
74178.
---------------------------------------------------------------------------

    \67\ On-board diagnostics (OBD) is a computer-based emissions 
monitoring system that was first required in 2007 for vehicles under 
14,000 pounds (65 FR 59896, Oct. 6, 2000) and in 2010 for vehicles 
over 14,000 pounds (74 FR 8310, Feb. 24, 2009).
---------------------------------------------------------------------------

    In response, Cummins, Engine Manufacturers Association, and DTNA 
commented that their first choice was a delay in the OBD effective date 
for one year to the 2014 model year. The industry's second choice was 
to provide manufacturers with an optional GHG and fuel consumption 
phase-in that aligns their product development plans with their current 
plans to meet the OBD regulations for EPA and California in the 2013 
and 2016 model years. These commenters argued that meeting the OBD 
regulation in the 2013 model year already poses a significant 
challenge, and that having to meet GHG and fuel consumption standards 
beginning in 2014 could require them to redesign and recertify their 
products just one year later. They argued that bundling design changes 
where possible can reduce the burden on industry for complying with 
regulations, so aligning the introduction of the OBD, GHG, and fuel 
consumption standards could help reduce manufacturers' burden for 
product development, validation and certification.
    In order to provide additional flexibility for manufacturers 
looking to align their technology changes with multiple regulatory 
requirements, the agencies are finalizing an alternate ``OBD phase-in'' 
option for meeting the standards for MHD and HHD diesel engines 
installed in tractors (in addition to engines installed in vocational 
vehicles as noted below in Section II.D), which delivers equivalent 
CO2 emissions and fuel consumption reductions as the primary 
standards for the engines built in the 2013 through 2017 model years, 
as shown in Table II-4. The optional OBD phase-in schedule requires 
that engines built in the 2013 and 2016 model years to achieve greater 
reductions than the engines built in those model years under the 
primary program, but requires fewer reductions for the engines built in 
the 2014 and 2015 model years.

 Table II-4--Comparison of CO2 reductions for the HHD and MHD Tractor Standards Under the Alternative OBD Phase-
                                             In and Primary Phase-In
----------------------------------------------------------------------------------------------------------------
                                             HHD Tractor engines                    MHD Tractor engines
                                   -----------------------------------------------------------------------------
                                                               Difference                             Difference
                                      Primary      Optional   in lifetime    Primary      Optional   in lifetime
                                      phase-in     phase-in    CO2 engine    phase-in     phase-in    CO2 engine
                                      standard     standard    emissions     standard     standard    emissions
                                     (g/bhp-hr)   (g/bhp-hr)     (MMT)      (g/bhp-hr)   (g/bhp-hr)     (MMT)
----------------------------------------------------------------------------------------------------------------
Baseline..........................          490          490           --          518          518           --
2013 MY Engine....................          490          485           14          518          512           17
2014 MY Engine....................          475          485          -28          502          512          -28
2015 MY Engine....................          475          485          -28          502          512          -28
2016 MY Engine....................          475          460           42          502          487           42
2017 MY Engine....................          460          460            0          487          487            0
Net Reductions (MMT)..............  ...........  ...........            0  ...........  ...........            3
----------------------------------------------------------------------------------------------------------------

[[Page 57144]]

    The technologies for the 2013 model year optional standard include 
a subset of technologies that could be used to meet the primary 2014 
model year standard. The agencies believe this approach is appropriate 
because the shorter lead time provided for manufacturers selecting this 
option limits the technologies which can be applied. However, in order 
to maintain equivalent CO2 emissions and fuel consumption 
reduction over the 2013 through 2017 model year period, it is necessary 
for the 2016 model year standard to be equal to the 2017 model year 
standard, using the same technology paths described for the primary 
engine program. If a manufacturer selects this optional phase-in, then 
the engines must be certified starting in the 2013 model year and 
continue using this phase-in through 2016 model year. That is, once 
electing this compliance path, manufacturers must adhere to it.\68\ 
Manufacturers may opt into the optional OBD phase-in through the 
voluntary NHTSA program, but must opt in in the 2013 model year and 
continue using this phase-in through the 2016 model year. Manufacturers 
that opt in to the voluntary NHTSA program in 2014 and 2015 will be 
required to meet the primary phase-in schedule and may not adopt the 
OBD phase-in option. Table II-5 below presents the final HD diesel 
engine CO2 emission standards under the ``OBD phase-in'' 
option.
---------------------------------------------------------------------------

    \68\ See Sec.  1036.150(e).

  Table II-5--Optional Heavy-Duty Engine Standard Phase-in Schedule for
                             Tractor Engines
------------------------------------------------------------------------
                                   MHD Diesel engine   HHD Diesel engine
------------------------------------------------------------------------
                 Effective 2013 Through 2015 Model Year
------------------------------------------------------------------------
CO2 Standard (g/bhp-hr).........                 512                 485
Voluntary Fuel Consumption                      5.03                4.76
 Standard (gallon/100 bhp-hr)...
------------------------------------------------------------------------
                   Effective 2016 Model Year and Later
------------------------------------------------------------------------
CO2 Standard (g/bhp-hr).........                 487                 460
Fuel Consumption (gallon/100 bhp-               4.78                4.52
 hr)............................
------------------------------------------------------------------------

    Although the agencies believe that the standards for the HD diesel 
engines installed in combination tractors are generally appropriate, 
cost-effective, and technologically feasible in the rulemaking time 
frame, we also recognize that when regulating a category of engines for 
the first time, there will be individual products that may deviate 
significantly from the baseline level of performance, whether because 
of a specific approach to criteria pollution control, or due to engine 
calibration for specific applications or duty cycles. In the current 
fleet of 2010 and 2011 model year engines used in combination tractors, 
NHTSA and EPA understand that there is a relatively small group of 
legacy engines that are up to approximately 25 percent worse than the 
average baseline for other engines. For this group of legacy MHD and 
HHD diesel engines installed in tractors, when compared to the typical 
performance levels of the majority of the engines in the fleet and the 
fuel consumption/GHG emissions reductions that the majority of engines 
would achieve through increased application of technology, the same 
reduction from the industry baseline may not be possible at reasonably 
comparable cost given the same amount of lead-time, because these 
products may require a total redesign in order to meet the standards. 
Manufacturers of the MHD and HHD diesel engines installed in tractors 
with atypically high baseline CO2 and fuel consumption 
levels may also, in some instances, have a limited line of engines 
across which to average performance to meet the generally-applicable 
standards.
    To account for this possibility, the agencies requested comment in 
the NPRM on the establishment of an optional alternative MHD and HHD 
engine standard for those engines installed in combination tractors 
which would be set at 3 percent below a manufacturer's 2011 engine 
baseline emissions and fuel consumption, or alternatively, at 2 percent 
below a manufacturer's 2011 baseline. The agencies also requested 
comment on extending this optional standard one year (to the 2017 MY) 
for a single engine family at a 6 percent level below the 2011 
baseline.\69\ This option would not be available unless and until a 
manufacturer had exhausted all available credits and credit 
opportunities, and engines under the optional standard could not 
generate credits.
---------------------------------------------------------------------------

    \69\ See 75 FR at 74178-74179.
---------------------------------------------------------------------------

    In comments to the NPRM, Navistar supported the alternative engine 
standard, but recommended that it be set at 2 percent below the 
manufacturer's 2011 baseline. They also supported the extension to 2017 
MY at 6 percent. Navistar provided CBI in support of its comments. 
Volvo, DTNA, environmental groups, NGOs, and the New York State 
Department of Environmental Conservation opposed the optional engine 
standard, arguing that existing flexibilities are sufficient to allow 
compliance with the standards and that all manufacturers should be held 
to the same standards.
    Based on the CBI submitted by Navistar, the agencies found that a 
large majority of the HD diesel engines used in Class 7 and 8 
combination tractors were relatively close to the average baseline, 
with some above and some below, but also that some legacy MHD and HDD 
diesel engines were far enough away from the baseline that they could 
not meet the generally-applicable standards with application of 
technology that would be available for those specific engines by 2014. 
The agencies continue to believe that an interim alternative standard 
is needed for these products, and that an interim standard reflects a 
legitimate difference between products starting from different fuel 
consumption/GHG emitting baselines. As explained in the proposal, it is 
legally permissible to accommodate short term lead time constraints 
with alternative standards. Commenters did not dispute that there are 
legacy engine families with significantly higher CO2 
emissions and fuel consumption baselines, and that these engines 
require longer lead time to meet the principal standards in the early 
model years of the program. Although the agencies acknowledge the view 
that all manufacturers should be subject to the same burden for meeting 
the primary standards, the agencies believe that, in the initial years 
of a new program,

[[Page 57145]]

additional flexibilities should be provided. The GHG standards and fuel 
consumption standards are first-time standards for these engines, so 
the possibility of significantly different baselines is not 
unexpected.\70\ Moreover, the agencies do not believe that the 
alternative standard affords a relative competitive advantage to the 
higher emitting legacy engines: the same level of improvement at the 
same cost will be required of those tractor engines, and in addition, 
by 2017 MY, those tractor engines will be required to make the 
additional improvements to meet the same standards as other engines. We 
believe that the concern expressed by Navistar regarding the 2014 MY 
standards will be addressed by this alternative. The agencies also 
continue to believe the 2017 MY standards are achievable using the 
above approaches and, in the case of MHD and HHD engines installed in 
tractors, turbocompounding. While Navistar commented that the 2017 MY 
standard may be challenging, the agencies believe that since 
manufacturers which may need to use turbocompounding to meet the 
standards will not have to do so until 2017 MY, there will be 
sufficient lead time for all engine manufacturers to introduce this 
technology. Thus, the agencies are finalizing a regulatory alternative 
whereby a manufacturer, for an interim period of the 2014-2016 model 
years, would have the option to comply with a unique standard based on 
a three percent reduction from an individual engine's own 2011 model 
year baseline level. Our assessment is that this three percent 
reduction is appropriate given the potential for manufacturers to apply 
similar technology packages with similar cost to what we have estimated 
for the primary program. This is similar to EPA's approach in the 
light-duty rule for handling a certain subset of vehicles that were 
deemed unable to meet the generally-applicable GHG standards during the 
2012-2015 time frame due to higher initial baseline conditions, and 
which therefore needed alternate standards in those model years.\71\
---------------------------------------------------------------------------

    \70\ See 75 FR at 74178.
    \71\ See 75 FR 25414-25419.
---------------------------------------------------------------------------

    The agencies stress that this is a temporary and limited option 
being implemented to address diverse manufacturer needs associated with 
complying with this first phase of the regulations. As codified in 40 
CFR 1036.620 and 49 CFR 535.5(d), this optional standard will be 
available only for the 2014 through 2016 model years, because we 
believe that manufacturers will have had ample opportunity to make 
appropriate changes to bring their product performance into line with 
the rest of the industry after that time. As proposed, the final rules 
require that manufacturers making use of these provisions for the 
optional standard would need to exhaust all credits available to this 
averaging set prior to using this flexibility and would not be able to 
generate emissions credits from other engines in the same regulatory 
averaging set as the engines complying using this alternate approach.
    The agencies note again that manufacturers choosing to utilize this 
option in MYs 2014-2016 will have to make a greater relative 
improvement in MY 2017 than the rest of the industry, since they will 
be starting from a worse level--for compliance purposes, emissions from 
engines certified and sold at the three percent level will be averaged 
with emissions from engines certified and sold at more stringent levels 
to arrive at a weighted average emissions for all engines in the 
subcategory. Again, this option can only be taken if all other credit 
opportunities have been exhausted and the manufacturer still cannot 
meet the primary standards. If a manufacturer chooses this option to 
meet the EPA emission standards in the MY 2014-2016, and wants to opt 
into the NHTSA fuel consumption program in these same MYs it must 
follow the exact path followed under the EPA program utilizing 
equivalent fuel consumption standards. Since the NHTSA standards are 
optional in 2014, manufacturers may choose not to adopt either the 
alternative engine standard or the regular voluntary standard by not 
participating in the NHTSA program in 2014 and 2015.
    Some commenters argued that manufacturers could game the standard 
by establishing an artificially high 2011 baseline emission level. This 
could be done, for example, by certifying an engine with high fuel 
consumption and GHG emissions that is either: (1) Not sold in 
significant quantities; or (2) later altered to emit fewer GHGs and 
consume less fuel through service changes. In order to mitigate this 
possibility, the agencies are requiring that the 2011 model year 
baseline must be developed by averaging emissions over all engines in 
an engine family certified and sold for that model year so as to 
prevent a manufacturer from developing a single high GHG output engine 
solely for the purpose of establishing a high baseline. As an 
alternative, if a manufacturer does not certify all engine families in 
an averaging set to the alternate standards, then the tested 
configuration of the engine certified to the alternate standard must 
have the same engine displacement and its rated power within 5 percent 
of the highest rated power of the baseline tested configuration. In 
addition, the tested configuration of the engine certified to the 
alternate standard must be a configuration sold to customers. These 
three requirements will prevent a manufacturer from producing an engine 
with an artificially high power rating and therefore produce 
artificially low grams of CO2 emissions and fuel consumption 
per brake horsepower. In addition, the tested configurations must have 
a BSFC equivalent to or better than all other configurations within the 
engine family which will prevent a manufacturer from creating a 
baseline configuration with artificially high CO2 emissions 
and fuel consumption.
(c) In-Use Standards
    Section 202(a)(1) of the CAA specifies that EPA is to adopt 
emissions standards that are applicable for the useful life of the 
vehicle. The in-use standards that EPA is finalizing would apply to 
individual vehicles and engines. NHTSA is adopting an approach which 
does not include in-use standards.
    EPA proposed that the in-use standards for heavy-duty engines 
installed in tractors be established by adding an adjustment factor to 
the full useful life emissions and fuel consumption results projected 
in the EPA certification process to address measurement variability 
inherent in comparing results among different laboratories and 
different engines. The agency proposed a two percent adjustment factor 
and requested comments and additional data during the proposal to 
assist in developing an appropriate factor level. The agency received 
additional data during the comment period which identified production 
variability which was not accounted for at proposal. Details on the 
development of the final adjustment factor are included in RIA Chapter 
3. Based on the data received, EPA determined that the adjustment 
factor in the final rules should be higher than the proposed level of 
two percent. EPA is finalizing a three percent adjustment factor for 
the in-use standard to provide a reasonable margin for production and 
test-to-test variability that could result in differences between the 
initial emission test results and emission results obtained during 
subsequent in-use testing.
    We are finalizing regulatory text (in Sec.  1036.150) to allow 
engine manufacturers to used assigned

[[Page 57146]]

deterioration factors (DFs) without performing their own durability 
emission tests or engineering analysis. However, the engines would 
still be required to meet the standards in actual use without regard to 
whether the manufacturer used the assigned DFs. This allowance is being 
adopted as an interim provision applicable only for this initial phase 
of standards.
    Manufacturers will be allowed to use an assigned additive DF of 0.0 
g/bhp-hr for CO2 emissions from any conventional engine 
(i.e., an engine not including advance or innovative technologies). 
Upon request, we could allow the assigned DF for CO2 
emissions from engines including advance or innovative technologies, 
but only if we determine that it would be consistent with good 
engineering judgment. We believe that we have enough information about 
in-use CO2 emissions from conventional engines to conclude 
that they will not increase as the engines age. However, we lack such 
information about the more advanced technologies.
    EPA is also finalizing the proposed provisions requiring that the 
useful life for these engine and vehicles with respect to GHG emissions 
be set equal to the respective useful life periods for criteria 
pollutants. EPA is adopting provisions where the existing engine useful 
life periods, as included in Table II-6, be broadened to include 
CO2 emissions for both engines (See 40 CFR 1036.108(d)) and 
tractors (See 40 CFR 1037.105).

           Table II-6--Tractor and Engine Useful Life Periods
------------------------------------------------------------------------
                                                      Years      Miles
------------------------------------------------------------------------
Medium Heavy-Duty Diesel Engines..................         10    185,000
Heavy Heavy-Duty Diesel Engines...................         10    435,000
Class 7 Tractors..................................         10    185,000
Class 8 Tractors..................................         10    435,000
------------------------------------------------------------------------

(3) Test Procedures and Related Issues
    The agencies are finalizing a complete set of test procedures to 
evaluate fuel consumption and CO2 emissions from Class 7 and 
8 tractors and the engines installed in them. Consistent with the 
proposal, the test procedures related to the tractors are all new, 
while the engine test procedures already established were built 
substantially on EPA's current non-GHG emissions test procedures, 
except as noted. This section discusses the final simulation model 
developed for demonstrating compliance with the tractor standard and 
the final engine test procedures.
(a) Vehicle Simulation Model
    We are finalizing as proposed separate engine and vehicle-based 
emission standards to achieve the goal of reducing emissions and fuel 
consumption for both combination tractors and engines. Engine 
manufacturers are subject to the engine standards while the Class 7 and 
8 tractor manufacturers are required to install certified engines in 
their tractors. The tractor manufacturer is also subject to a separate 
vehicle-based standard which utilizes a vehicle simulation model to 
evaluate the impact of the tractor cab design to determine compliance 
with the tractor standard.
    A simulation model, in general, uses various inputs to characterize 
a vehicle's properties (such as weight, aerodynamics, and rolling 
resistance) and predicts how the vehicle would behave on the road when 
it follows a driving cycle (vehicle speed versus time). On a second-by-
second basis, the model determines how much engine power needs to be 
generated for the vehicle to follow the driving cycle as closely as 
possible. The engine power is then transmitted to the wheels through 
transmission, driveline, and axles to move the vehicle according to the 
driving cycle. The second-by-second fuel consumption of the vehicle, 
which corresponds to the engine power demand to move the vehicle, is 
then calculated according to a fuel consumption map in the model. 
Similar to a chassis dynamometer test, the second-by-second fuel 
consumption is aggregated over the complete drive cycle to determine 
the fuel consumption of the vehicle.
    Consistent with the proposal, NHTSA and EPA are finalizing a 
procedure to evaluate fuel consumption and CO2 emissions 
respectively through a simulation of whole-vehicle operation, 
consistent with the NAS recommendation to use a truck model to evaluate 
truck performance.\72\ The EPA developed the Greenhouse gas Emissions 
Model (GEM) for the specific purpose of this rulemaking to evaluate 
truck performance. The GEM is similar in concept to a number of vehicle 
simulation tools developed by commercial and government entities. The 
model developed by the EPA and finalized here was designed for the 
express purpose of vehicle compliance demonstration and is therefore 
simpler and less configurable than similar commercial products. This 
approach gives a compact and quicker tool for vehicle compliance 
without the overhead and costs of a more sophisticated model. Details 
of the model are included in Chapter 4 of the RIA. The agencies are 
aware of several other simulation tools developed by universities and 
private companies. Tools such as Argonne National Laboratory's 
Autonomie, Gamma Technologies' GT-Drive, AVL's CRUISE, Ricardo's VSIM, 
Dassault's DYMOLA, and University of Michigan's HE-VESIM codes are 
publicly available. In addition, manufacturers of engines, vehicles, 
and trucks often have their own in-house simulation tools. The agencies 
sought comments regarding other software packages which would better 
serve the compliance purposes of the rules than the GEM, but did not 
receive any recommendations.
---------------------------------------------------------------------------

    \72\ See 2010 NAS Report. Note 21, Recommendation 8-4. Page 190.
---------------------------------------------------------------------------

    The GEM is designed to focus on the inputs most closely associated 
with fuel consumption and CO2 emissions--i.e., on those 
which have the largest impacts such as aerodynamics, rolling 
resistance, weight, and others.
    EPA has validated the GEM based on the chassis test results from 
two combination tractors tested at Southwest Research Institute. The 
validation work conducted on this vehicle was representative of the 
other Class 7 and 8 tractors. Many aspects of one tractor configuration 
(such as the engine, transmission, axle configuration, tire sizes, and 
control systems) are similar to those used on the manufacturer's sister 
models. For example, the powertrain configuration of a sleeper cab with 
any roof height is similar to the one used on a day cab with any roof 
height. Overall, the GEM predicted the fuel consumption and 
CO2 emissions within 2 percent of the chassis test procedure 
results for three test cycles--the California ARB Transient cycle, 65 
mph cruise cycle, and 55 mph cruise cycle. These cycles are the ones 
the agencies are utilizing in compliance testing. Since the time of the 
proposal, the EPA also conducted a validation of the GEM relative to a 
commonly used vehicle simulation software, GT-Power. The results of 
this validation found that the two software programs predicted the fuel 
efficiency of each subcategory of tractor to be within 2 percent. Test 
to test variation for heavy-duty vehicle chassis testing can be higher 
than 4 percent due to driver variation alone. The final simulation 
model is described in greater detail in Chapter 4 of the RIA and is 
available for download by at (http://www.epa.gov/otaq/climate/regulations.htm).
    After proposal, the agencies conducted a peer review of GEM version 
1.0 which was proposed. In addition, we requested comment on all 
aspects of

[[Page 57147]]

this approach to compliance determination in general and to the use of 
the GEM in particular. The agencies received comments from stakeholders 
and made changes for the release of GEM v2.0 to address concerns raised 
in the comments, along with the comments received during the peer 
review process. The most noticeable changes to the GEM include 
improvements to the graphical user interface (GUI). In response to 
comments, the agencies have reduced the amount of information required 
in the Identification section; linked the inputs to the selected 
subcategory while graying-out the items that are not applicable to the 
subcategory; and added batch modeling capability to reduce the 
compliance burden to manufacturers. In addition, substantial work went 
into model validations and benchmarking against vehicle test data and 
other commonly used vehicle simulation models.
    The model also includes a new driver model, a simplified electric 
system model, and revised engine fuel maps to better reflect the 2017 
model year engine standards. The model in the final rulemaking uses the 
targeted vehicle driving speed to estimate vehicle torque demand at any 
given time, and then the power required to drive the vehicle is derived 
to estimate the required accelerator and braking pedal positions. If 
the driver misses the vehicle speed target, a speed correction logic 
controlled by a PID controller is applied to adjust necessary 
accelerator and braking pedal positions in order to match targeted 
vehicle speed at every simulation time step. The enhanced driver model 
used in the final rulemaking with its feed-forward driver controls more 
realistically models driving behavior. The GEM v1.0, the proposed 
version of the model, had four individual components to model the 
electric system--starter, electrical energy system, alternator, and 
electrical accessory. For the final rulemaking, the GEM v2.0 has a 
single electric system model with a constant power consumption level. 
Based on comments received, the agencies revisited the 2017 model year 
proposed fuel maps, specifically the low load area, which was 
extrapolated during the proposal and (incorrectly) generated negative 
improvements. The agencies redeveloped the fuel maps for the final 
rulemaking to better predict the fuel consumption of engines in this 
area of the fuel consumption map. Details of the changes are included 
in RIA Chapter 4.
    To demonstrate compliance, a Class 7 and 8 tractor manufacturer 
will measure the performance of specified tractor systems (such as 
aerodynamics and tire rolling resistance), input the values into the 
GEM, and compare the model's output to the standard. The rules require 
that a tractor manufacturer provide the inputs for each of following 
factors for each of the tractors it wishes to certify under 
CO2 standards and for establishing fuel consumption values: 
Coefficient of Drag, Tire Rolling Resistance Coefficient, Weight 
Reduction, Vehicle Speed Limiter, and Extended Idle Reduction 
Technology. These are the technologies on which the agencies' own 
feasibility analysis for these vehicles is predicated. An example of 
the GEM input screen is included in Figure II-1.
[GRAPHIC] [TIFF OMITTED] TR15SE11.001

    For the aerodynamic assessment, tire rolling resistance, and 
tractor weight reduction, the input values for the simulation model 
will be determined by the manufacturer through conducting tests using 
the test procedures finalized

[[Page 57148]]

by the agencies in this action and described below. The agencies are 
allowing several testing alternatives for aerodynamic assessment 
referenced back to a coastdown test procedure, a single procedure for 
determination of the coefficient of rolling resistance (CRR) for tires, 
and a prescribed method to determine tractor weight reduction. The 
agencies have finalized defined model inputs for determining vehicle 
speed limiter and extended idle reduction technology benefits. The 
other aspects of vehicle performance are fixed within the model as 
defined by the agencies and are not varied for the purpose of 
compliance.
(b) Metric
    Test metrics which are quantifiable and meaningful are critical for 
a regulatory program. The CO2 and fuel consumption metric 
should reflect what we wish to control (CO2 or fuel 
consumption) relative to the clearest value of its use: in this case, 
carrying freight. It should encourage efficiency improvements that will 
lead to reductions in emissions and fuel consumption during real world 
operation. The agencies are finalizing standards for Class 7 and 8 
combination tractors that would be expressed in terms of moving a ton 
(2,000 pounds) of freight over one mile. Thus, NHTSA's final fuel 
consumption standards for these trucks would be represented as gallons 
of fuel used to move one ton of freight 1,000 miles, or gal/1,000 ton-
mile. EPA's final CO2 vehicle standards would be represented 
as grams of CO2 per ton-mile. The model converts 
CO2 emissions to fuel consumption using the CO2 
grams per ton mile estimated by GEM and an assumed 10,180 grams of 
CO2 per gallon of diesel fuel.
    This approach tracks the recommendations of the NAS report. The NAS 
panel concluded, in their report, that a load-specific fuel consumption 
metric is appropriate for HD trucks. The panel spent considerable time 
explaining the advantages of and recommending a load-specific fuel 
consumption approach to regulating the fuel efficiency of heavy-duty 
trucks. See NAS Report pages 20 through 28. The panel first points out 
that the nonlinear relationship between fuel economy and fuel 
consumption has led consumers of light-duty vehicles to have difficulty 
in judging the benefits of replacing the most inefficient vehicles. The 
panel describes an example where a light-duty vehicle can save the same 
107 gallons per year (assuming 12,000 miles travelled per year) by 
improving one vehicle's fuel efficiency from 14 to 16 mpg or improving 
another vehicle's fuel efficiency from 35 to 50.8 mpg. The use of miles 
per gallon leads consumers to undervalue the importance of small mpg 
improvements in vehicles with lower fuel economy. Therefore, the NAS 
panel recommends the use of a fuel consumption metric over a fuel 
economy metric. The panel also describes the primary purpose of most 
heavy-duty vehicles as moving freight or passengers (the payload). 
Therefore, they concluded that the most appropriate way to represent an 
attribute-based fuel consumption metric is to normalize the fuel 
consumption to the payload.
    With the approach to compliance NHTSA and EPA are adopting, a 
default payload is specified for each of the tractor categories 
suggesting that a gram per mile metric with a specified payload and a 
gram per ton-mile metric would be effectively equivalent. The primary 
difference between the metrics and approaches relates to our treatment 
of mass reductions as a means to reduce fuel consumption and greenhouse 
gas emissions. In the case of a gram per mile metric, mass reductions 
are reflected only in the calculation of the work necessary to move the 
vehicle mass through the drive cycle. As such it directly reduces the 
gram emissions in the numerator since a vehicle with less mass will 
require less energy to move through the drive cycle leading to lower 
CO2 emissions. In the case of Class 7 and 8 tractors and our 
gram/ton-mile metric, reductions in mass are reflected both in less 
mass moved through the drive cycle (the numerator) and greater payload 
(the denominator). We adjust the payload based on vehicle mass 
reductions because we estimate that approximately one third of the time 
the amount of freight loaded in a trailer is limited not by volume in 
the trailer but by the total gross vehicle weight rating of the 
tractor. By reducing the mass of the tractor the mass of the freight 
loaded in the vehicle can go up. Based on this general approach, it can 
be estimated that for every 1,200 pounds in mass reduction across all 
Class 7 and 8 tractors on the road, that total vehicle miles traveled, 
and therefore trucks on the road, could be reduced by one percent. 
Without the use of a per ton-mile metric it would not be clear or 
straightforward for the agencies to reflect the benefits of mass 
reduction from large freight carrying vehicles that are often limited 
in the freight they carry by the gross vehicle weight rating of the 
vehicle. There was strong consensus in the public comments for adopting 
the proposed metrics for tractors.
(c) Vehicle Aerodynamic Assessment
    The aerodynamic drag of a vehicle is determined by the vehicle's 
coefficient of drag (Cd), frontal area, air density and speed. As noted 
in the NPRM, quantifying truck aerodynamics as an input to the GEM 
presents technical challenges because of the proliferation of vehicle 
configurations, the lack of a clearly preferable standardized test 
method, and subtle variations in measured aerodynamic values among 
various test procedures. Class 7 and 8 tractor aerodynamics are 
currently developed by manufacturers using a range of techniques, 
including wind tunnel testing, computational fluid dynamics, and 
constant speed tests.
    Consistent with our discussion at proposal, we believe a broad 
approach allowing manufacturers to use these multiple different test 
procedures to demonstrate aerodynamic performance of its tractor fleet 
is appropriate given that no single test procedure is superior in all 
aspects to other approaches. Allowing manufacturers to use multiple 
test procedures and modeling coupled with good engineering judgment to 
determine aerodynamic performance is consistent with the current 
approach used in determining representative road load forces for light-
duty vehicle testing (40 CFR 86.129-00(e)(1)). However, we also 
recognize the need for consistency and a level playing field in 
evaluating aerodynamic performance.
    The agencies are retaining an aerodynamic bin structure for the 
final rulemaking, but are adjusting the method used to determine the 
bins. To address the consistency and level playing field concerns, 
NHTSA and EPA proposed that manufacturers use a two-part screening 
approach for determining the aerodynamic inputs to the GEM. The first 
part would have required the manufacturers to assign each vehicle 
aerodynamic configuration based on descriptions of vehicle 
characteristics to one of five aerodynamics bins created by EPA and 
NHTSA. The proposed assignment by bin would have fixed (by rule) the 
aerodynamic characteristics of the vehicle. However, the agencies, 
while working with industry, concluded for the final rulemaking that an 
approach which identified a reference aerodynamic test method and a 
procedure to align results from other aerodynamic test procedures with 
the reference method is a simpler, more accurate approach than 
deciphering and interpreting written descriptions of aerodynamic 
components.
    Therefore, we are finalizing an approach, as described in Section 
V.B.3.d and Sec.  1037.501, which uses an

[[Page 57149]]

enhanced coastdown procedure as a reference method and defines a 
process for manufacturers to align drag results from each of their own 
test methods to the reference method results. Manufacturers will be 
able to use any aerodynamic evaluation method in demonstrating a 
vehicle's aerodynamic performance as long as the method is aligned to 
the reference method. The results from the aerodynamic testing will be 
the single determining factor for aerodynamic bin assignments.
    EPA and NHTSA recognize that wind conditions, most notably wind 
direction, have a greater impact on real world CO2 emissions 
and fuel consumption of heavy-duty trucks than of light-duty vehicles. 
As noted in the NAS report,\73\ the wind average drag coefficient is 
about 15 percent higher than the zero degree coefficient of drag. In 
addition, the agencies received comments that supported the use of wind 
averaged drag results for the aerodynamic determination. The agencies 
considered finalizing the use of a wind averaged drag coefficient in 
this regulatory program, but ultimately decided to finalize drag values 
which represent zero yaw (i.e., representing wind from directly in 
front of the vehicle, not from the side) instead. We are taking this 
approach recognizing that the reference method is coastdown testing 
which is not capable of determining wind averaged yaw. Wind tunnels are 
currently the only tool which can accurately assess the influence of 
wind speed and direction on a vehicle's aerodynamic performance. The 
agencies recognize, as NAS did, that the results of using the zero yaw 
approach may result in fuel consumption predictions that are offset 
slightly from real world performance levels, not unlike the offset we 
see today between fuel economy test results in the CAFE program and 
actual fuel economy performance observed in-use. We believe this 
approach will not impact overall technology effectiveness or change the 
kinds of technology decisions made by the tractor manufacturers in 
developing equipment to meet our final standards. However, the agencies 
are adopting provisions which allow manufacturers to generate credits 
reflecting performance of technologies which improve the aerodynamic 
performance in crosswind conditions, similar to those experienced by 
vehicles in use through innovative technologies, as described in 
Section IV.
---------------------------------------------------------------------------

    \73\ See 2010 NAS Report, Note 21, Finding 2-4 on page 39.
---------------------------------------------------------------------------

    As just noted, the agencies are adopting an approach for this final 
action where the manufacturer would determine a tractor's aerodynamic 
drag force using their own aerodynamic assessment tools and correlating 
the results back to the reference aerodynamic test method of enhanced 
coastdown testing. The manufacturer determines the appropriate 
predefined aerodynamic bin based on the correlated test results and 
then inputs the predefined Cd value for that aerodynamic bin into the 
GEM. Coefficient of drag and frontal area of the tractor-trailer 
combination go hand-in-hand to determine the force required to overcome 
aerodynamic drag. The agencies proposed that the Cd value would be a 
GEM input derived by the manufacturer and that the agencies would 
specify the vehicle's frontal area for each regulatory subcategory. The 
agencies sought and received comment recommending an alternate approach 
where the aerodynamic input tables (as shown in Table 0-7 and Table 0-
8) represent the drag force as defined as Cd multiplied by the frontal 
area. Because both approaches are essentially equivalent and the use of 
CdA more directly relates back to the aerodynamic testing, the agencies 
are finalizing the use of CdA as recommended by manufacturers.
    The agencies are finalizing aerodynamic technology bins which 
divide the wide spectrum of tractor aerodynamics into five bins (i.e., 
categories) for high roof tractors. The first high roof category, Bin 
I, is designed to represent tractor bodies which prioritize appearance 
or special duty capabilities over aerodynamics. These Bin I trucks 
incorporate few, if any, aerodynamic features and may have several 
features which detract from aerodynamics, such as bug deflectors, 
custom sunshades, B-pillar exhaust stacks, and others. The second high 
roof aerodynamics category is Bin II which roughly represents the 
aerodynamic performance of the average new tractor sold today. The 
agencies developed this bin to incorporate conventional tractors which 
capitalize on a generally aerodynamic shape and avoid classic features 
which increase drag. High roof tractors within Bin III build on the 
basic aerodynamics of Bin II tractors with added components to reduce 
drag in the most significant areas on the tractor, such as integral 
roof fairings, side extending gap reducers, fuel tank fairings, and 
streamlined grill/hood/mirrors/bumpers, similar to SmartWay trucks 
today. The Bin IV aerodynamic category for high roof tractors builds 
upon the Bin III tractor body with additional aerodynamic treatments 
such as underbody airflow treatment, down exhaust, and lowered ride 
height, among other technologies. And finally, Bin V tractors 
incorporate advanced technologies which are currently in the prototype 
stage of development, such as advanced gap reduction, rearview cameras 
to replace mirrors, wheel system streamlining, and advanced body 
designs.
    The agencies had proposed five aerodynamic bins for each tractor 
regulatory subcategory. The agencies received comments from ATA, EMA/
TMA, and Volvo indicating that this approach was not consistent with 
the aerodynamics of low and mid roof tractors. High roof tractors are 
consistently paired with box trailer designs, and therefore 
manufacturers can design the tractor aerodynamics as a tractor-trailer 
unit and target specific areas like the gap between the tractor and 
trailer. In addition, the high roof tractors tend to spend more time at 
high speed operation which increases the impact of aerodynamics on fuel 
consumption and GHG emissions. On the other hand, low and mid roof 
tractors are designed to pull variable trailer loads and shapes. They 
may pull trailers such as flat bed, low boy, tankers, or bulk carriers. 
The loads on flat bed trailers can range from rectangular cartons with 
tarps, to a single roll of steel, to a front loader. Due to these 
variables, manufacturers do not design unique low and mid roof tractor 
aerodynamics but instead use derivatives from their high roof tractor 
designs. The aerodynamic improvements to the bumper, hood, windshield, 
mirrors, and doors are developed for the high roof tractor application 
and then carried over into the low and mid roof applications. As 
mentioned above, the types of designs that would move high roof 
tractors from a Bin III to Bins IV and V include features such as gap 
reducers and integral roof fairings which would not be appropriate on 
low and mid roof tractors. The agencies considered and largely agree 
with these comments and are therefore finalizing only two aerodynamic 
bins for low and mid roof tractors. The agencies are reducing the 
number of bins to reflect the actual range of aerodynamic technologies 
effective in low and mid roof tractor applications. Thus, the agencies 
are differentiating the aerodynamic performance for low and mid roof 
applications into two bins--conventional and aerodynamic.\74\
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    \74\ As explained in Section IV, there are no ABT implications 
to this change from proposal, since all Class 8 combination tractors 
are considered to be a single averaging set for ABT purposes. 
Similarly, all Class 7 tractors are considered to be a single 
averaging set for ABT purposes.

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[[Page 57150]]

    For high roof combination tractor compliance determination, a 
manufacturer would use the aerodynamic results determined through 
testing to establish the appropriate bin. The manufacturer would then 
input into GEM the Cd value specified for each bin as defined in Table 
II-7 and Table II-8. For example, if a manufacturer tests a Class 8 
sleeper cab high roof tractor and the test produces a CdA value between 
5.8 and 6.6, the manufacturer would assign this tractor to the Class 8 
Sleeper Cab High Roof Bin III. The manufacturer would then use the Cd 
value identified for Bin III of 0.60 as the input to GEM.
    The Cd values in Table II-7 and Table II-8 differ from proposal 
based on a change in the reference method (enhanced coastdown 
procedure) and additional testing conducted by EPA. Details of the test 
program and results are included in RIA Chapter 2.5.1.4.

 Table II-7--Aerodynamic Input Definitions to GEM for High Roof Tractors
------------------------------------------------------------------------
                                     Class 7             Class 8
                                  --------------------------------------
                                     Day cab      Day cab    Sleeper cab
                                  --------------------------------------
                                    High roof    High roof   High roof >
------------------------------------------------------------------------
                 Aerodynamic Test Results (CdA in m\2\)
------------------------------------------------------------------------
Bin I............................       >= 8.0       >= 8.0       >= 7.6
Bin II...........................      7.1-7.9      7.1-7.9      6.7-7.5
Bin III..........................      6.2-7.0      6.2-7.0      5.8-6.6
Bin IV...........................      5.6-6.1      5.6-6.1      5.2-5.7
Bin V............................       = 5.1       >= 5.6       >= 5.1       >= 5.6       >= 5.1       >= 5.6
Bin II............................................................       metric ton). The agencies 
are finalizing as proposed that three tire samples within each tire 
model be tested three times each to account for some of the production 
variability and the average of the nine tests would be the rolling 
resistance coefficient for the tire. The GEM will use the steer and 
drive tire rolling resistance inputs and distribute 15 percent of the 
gross weight of the tractor and trailer to the steer axle, 42.5 percent 
to the drive axles, and 42.5 percent to the trailer axles.\77\ The 
trailer tires' rolling resistance is prescribed by the agencies as part 
of the standardized trailer used for demonstrating compliance at 6 kg/
metric ton, which was the average trailer tire rolling resistance 
measured during the SmartWay tire testing.\78\
---------------------------------------------------------------------------

    \75\ ISO, 2009, Passenger Car, Truck, and Bus Tyres--Methods of 
Measuring Rolling Resistance--Single Point Test and Correlation of 
Measurement Results: ISO 28580:2009(E), First Edition, 2009-07-01
    \76\ NHTSA, 2009. ``NHTSA Tire Fuel Efficiency Consumer 
Information Program Development: Phase 1--Evaluation of Laboratory 
Test Protocols.'' DOT HS 811 119. June. (http://www.regulations.gov, 
Docket ID: NHTSA-2008-0121-0019).
    \77\ This distribution is equivalent to the federal over-axle 
weight limits for an 80,000 GVWR 5-axle tractor-trailer: 12,000 
pounds over the steer axle, 34,000 pounds over the tandem drive 
axles (17,000 pounds per axle) and 34,000 pounds over the tandem 
trailer axles (17,000 pounds per axle).
    \78\ U.S. Environmental Protection Agency. SmartWay Transport 
Partnership July 2010 e-update accessed July 16, 2010, from http://www.epa.gov/smartwaylogistics/newsroom/documents/e-update-july-10.pdf.
---------------------------------------------------------------------------

    EPA and NHTSA conducted additional evaluation testing on HD trucks 
tires used for tractors, and also for vocational vehicles. The agencies 
also received several comments on the suitability of low rolling 
resistance tires for various HD vehicle applications. The summary of 
the agencies' findings and a response to issues raised by commenters is 
presented in Section II.D(1)(a).
(e) Weight Reduction Assessment
    The agencies proposed that the tractor standards reflect improved 
CO2 emissions and fuel consumption performance of a 400 
pound weight reduction in Class 7 and 8 tractors through the 
substitution of single wide tires and light-weight wheels for dual 
tires and steel wheels. This approach was taken since there is a large 
variation in the baseline weight among trucks that perform roughly 
similar functions with roughly similar configurations. Because of this, 
the only effective way to quantify the exact CO2 and fuel 
consumption benefit of mass reduction using GEM is to estimate baseline 
weights for specific components that can be replaced with light weight 
components. If the weight reduction is specified for light weight 
versions of specific components, then both the baseline and weight 
differentials for these are readily quantifiable and well-understood. 
Lightweight wheels are commercially available as are single wide tires 
and thus data on the weight reductions attributable to these two 
approaches are readily available.
    The agencies received comments on this approach from Volvo, ATA, 
MEMA, Navistar, American Chemistry Council, the Auto Policy Center, 
Iron and Steel Institute, Arvin Meritor, Aluminum Association, and 
environmental groups and NGOs. Volvo and ATA stated that not all fleets 
can use single wide tires and if this is the case the 400 pound weight 
reduction target cannot be met. Volvo stated that without the use of 
single wide drive tires, a 6x4 tractor will have a maximum weight 
reduction of 300 pounds if the customer selects all ten wheels to be 
outfitted with light weight aluminum wheels. A number of additional 
commenters--including American Chemistry Council, The Auto Policy 
Center, Iron and Steel Institute, Aluminum Association, Arvin Meritor, 
MEMA, Navistar, Volvo, and environmental and nonprofit groups--stated 
that manufacturers should be allowed to use additional light weight 
components in order to meet the tractor fuel consumption and 
CO2 emissions standards. These groups stated that weight 
reductions should not be limited to wheels and tires. They asked that 
cab doors, cab sides and backs, cab underbodies, frame rails, cross 
members, clutch housings, transmission cases, axle differential carrier 
cases, brake drums, and other components be allowed to be replaced with 
light-weight versions. Materials suggested for substitution included 
aluminum, light-weight aluminum, high strength steel, and plastic 
composites. The American Iron and Steel Institute stated there are 
opportunities to reduce mass by replacing mild steel--which currently 
dominates the heavy-duty industry--with high strength steel.
    In addition, The American Auto Policy Center asked that 
manufacturers be allowed to use materials other than aluminum and high 
strength steel to comply with the regulations. DTNA asked that weight 
reduction due to engine downsizing be allowed to receive credit. Volvo 
requested that weight reductions due to changes in axle configuration 
be credited. They used the example of a customer selecting a 4 X 2 over 
a 6 X 4 axle tractor. In this case, they assert there would be a 1,000 
pound weight savings from removing an axle.
    As proposed, many of the material substitutions could have been 
considered as innovative technologies for tractors and hence eligible 
for off cycle credits (so that the commenters overstated that these 
technologies were `disallowed'). Nonetheless in response to the above 
summarized comments, the agencies evaluated whether additional 
materials and components could be used directly for compliance with the 
tractor weight reduction through the primary program (i.e. be available 
as direct inputs to the GEM). The agencies reviewed comments and data 
received in response to the NPRM and additional studies cited by 
commenters. A summary of this review is provided in the following 
paragraphs.
    TIAX, in their report to the NAS, cited information from Alcoa 
identifying several mass reduction opportunities from material 
substitution in the tractor cab components which were similar to the 
ones identified by the Aluminum Association in their comments to this 
rulemaking.\79\ TIAX included studies submitted by Alcoa showing the 
potential to reduce the weight of a tractor-trailer combination by 
3,500 to 4,500 pounds.\80\ In addition, the U.S. Department of Energy 
has several projects underway to improve the freight efficiency of 
Class 8 trucks which provide relevant data: \81\ DOE reviewed 
prospective lightweighting alternative materials and found that 
aluminum has a potential to reduce mass by 40 to 60 percent, which is 
in line with the estimates of mass reductions of various components 
provided by Alcoa, and by the Aluminum Association in their comments 
and as cited in the TIAX report. These combined studies, comments, and 
additional data provided information on specific components that could 
be replaced with aluminum components.
---------------------------------------------------------------------------

    \79\ TIAX, LLC. ``Assessment of Fuel Economy Technologies for 
Medium- and Heavy-Duty Vehicles,'' Final Report to National Academy 
of Sciences, November 19, 2009. Pages 4-62 through 4-64.
    \80\ Alcoa. ``Improving Sustainability of Transport: Aluminum is 
Part of the Solution.'' 2009.
    \81\ Schutte, Carol. U.S. Department of Energy, Vehicle 
Technologies Program. ``Losing Weight--an enabler for a Systems 
Level Technology Development, Integration, and Demonstration for 
Efficient Class 8 Trucks (SuperTruck) and Advanced Technology 
Powertrains for Light-Duty Vehicles.''
---------------------------------------------------------------------------

    With regard to high strength steel, the Iron and Steel Institute 
found that the use of high strength steel and redesign can reduce the 
weight of light-duty trucks by 25 percent.\82\ Approximately

[[Page 57152]]

10 percent of this reduction results from material substitution and 15 
percent from vehicle re-design. While this study evaluated light-duty 
trucks, the agencies believe that a similar reduction could be achieved 
in heavy-duty trucks since the reductions from material substitution 
would likely be similar in heavy-trucks as in light-trucks. U.S. DOE, 
in the report noted above, identified opportunities to reduce mass by 
10 percent through high strength steel.\83\ This study was also for 
light-duty vehicles.
---------------------------------------------------------------------------

    \82\ American Iron and Steel Institute. ``A Cost Benefit 
Analysis Report to the North American Steel Industry on Improved 
Materials and Powertrain Architectures for 21st Century Trucks.''
    \83\ Schutte, Carol. U.S. Department of Energy, Vehicle 
Technologies Program. ``Losing Weight--an enabler for a Systems 
Level Technology Development, Integration, and Demonstration for 
Efficient Class 8 Trucks (SuperTruck) and Advanced Technology 
Powertrains for Light-Duty Vehicles''.
---------------------------------------------------------------------------

    The agencies considered other materials such as plastic composites 
and magnesium substitutes but were not able to obtain weights for 
specific components made from these materials. We have therefore not 
included components made from these materials as possible substitutes 
in the primary program, but they may be considered through the 
innovative technology/off-cycle credits provision. We may consider 
including these materials as part of the primary compliance option in a 
subsequent regulation if data become available.
    Based on this analysis, the agencies developed an expanded list of 
weight reduction opportunities for the final rulemaking that may be 
reflected in the GEM, as listed in Table II-9. The list includes 
additional components, but not materials, from those proposed. For high 
strength steel, the weight reduction value is equal to 10 percent of 
the presumed baseline component weight, as the agencies used a 
conservative value based on the DOE report. We recognize that there may 
be additional potential for weight reduction in new high strength steel 
components which combine the reduction due to the material substitution 
along with improvements in redesign, as evidenced by the studies done 
for light-duty vehicles. In the development of the high strength steel 
component weights, we are only assuming a reduction from material 
substitution and no weight reduction from redesign, since we do not 
have any data specific to redesign of heavy-duty components nor do we 
have a regulatory mechanism to differentiate between material 
substitution and improved design. We are finalizing for wheels that 
both aluminum and light weight aluminum are eligible to be used as 
light-weight materials. Aluminum, but not light-weight aluminum, can be 
used as a light-weight material for other components. The reason for 
this is that data were available for light weight aluminum for wheels 
but were not available for other components.
    The agencies received comments on the proposal from the American 
Chemistry Council highlighting the role of plastics and composites in 
heavy-duty vehicles. As they stated, composites can be low density 
while having high strength and are currently used in applications such 
as oil pans and buses. The DOE mass reduction program demonstrated for 
heavy vehicles proof of concept designs for hybrid composite doors with 
an overall mass savings of 40 percent; 30 percent mass reduction of a 
hood system with carbon fiber sheet molding compound; 50 percent mass 
reduction from composite tie rods, trailing arms, and axles; and 
superplastically formed aluminum body panels.\84\ While the agencies 
recognize these opportunities, we do not believe the technologies have 
advanced far enough to quantify the benefits of these materials because 
they are very dependent on the actual composite material. The agencies 
may consider such lightweighting opportunities in future actions, but 
are not including them as part of this primary program. Manufacturers 
which opt to pursue composite and plastic material substitutions may 
seek credits through the innovative technology provisions.
---------------------------------------------------------------------------

    \84\ Schutte, Carol. U.S. Department of Energy, Vehicle 
Technologies Program. ``Losing Weight--an enabler for a Systems 
Level Technology Development, Integration, and Demonstration for 
Efficient Class 8 Trucks (SuperTruck) and Advanced Technology 
Powertrains for Light-Duty Vehicles''.
---------------------------------------------------------------------------

    With regard to Volvo's request that manufacturers be allowed to 
receive credit for trucks with fewer axles, the agencies recognize that 
vehicle options exist today which have less mass than other options. 
However, we believe the decisions to add or subtract such components 
will be made based on the intended use of the vehicle and not based on 
a crediting for the mass difference in our compliance program. It is 
not our intention to create a tradeoff between the right vehicle to 
serve a need (e.g. one with more or fewer axles) and compliance with 
our final standards. Therefore, we are not including provisions to 
credit (or penalize) vehicle performance based on the subtraction (or 
addition) of specific vehicle components. Table II-9 provides weight 
reduction values for different components and materials.

                   Table II-9--Weight Reduction Values
------------------------------------------------------------------------
 
------------------------------------------------------------------------
       Weight reduction technology        Weight reduction (lb per tire/
                                                      wheel)
------------------------------------------------------------------------
Single Wide Drive Tire with:
    Steel Wheel.........................                84
    Aluminum Wheel......................                139
    Light Weight Aluminum Wheel.........                147
Steer Tire or Dual Wide Drive Tire with:
    High Strength Steel Wheel...........                 8
    Aluminum Wheel......................                21
    Light Weight Aluminum Wheel.........                30
------------------------------------------------------------------------
      Weight reduction technologies          Aluminum      High strength
                                              weight       steel weight
                                             reduction       reduction
                                               (lb.)           (lb.)
------------------------------------------------------------------------
Door....................................              20               6
Roof....................................              60              18
Cab rear wall...........................              49              16
Cab floor...............................              56              18
Hood Support Structure..................              15               3

[[Page 57153]]

 
Fairing Support Structure...............              35               6
Instrument Panel Support Structure......               5               1
Brake Drums--Drive (4)..................             140              11
Brake Drums--Non Drive (2)..............              60               8
Frame Rails.............................             440              87
Crossmember--Cab........................              15               5
Crossmember--Suspension.................              25               6
Crossmember--Non Suspension (3).........              15               5
Fifth Wheel.............................             100              25
Radiator Support........................              20               6
Fuel Tank Support Structure.............              40              12
Steps...................................              35               6
Bumper..................................              33              10
Shackles................................              10               3
Front Axle..............................              60              15
Suspension Brackets, Hangers............             100              30
Transmission Case.......................              50              12
Clutch Housing..........................              40              10
Drive Axle Hubs (8).....................             160               4
Non Drive Front Hubs (2)................              40               5
Driveshaft..............................              20               5
Transmission/Clutch Shift Levers........              20               4
------------------------------------------------------------------------

    EPA and NHTSA are specifying the baseline vehicle weight for each 
regulatory vehicle subcategory (including the tires, wheels, frame, and 
cab components) in the GEM in aggregate based on weight of vehicles 
used in EPA's aerodynamic test program, but allow manufacturers to 
specify the use of light-weight components. The GEM then quantifies the 
weight reductions based on the pre-determined weight of the baseline 
component minus the pre-determined weight of the component made from 
light-weight material. Manufacturers cannot specify the weight of the 
light-weight component themselves, only the material used in the 
substitute component. The agencies assume the baseline wheel and tire 
configuration contains dual tires with steel wheels, along with steel 
frame and cab components, because these represent the vast majority of 
new vehicle configurations today. The weight reduction due to 
replacement of components with light weight versions will be reflected 
partially in the payload tons and partially in reducing the overall 
weight of the vehicle run in the GEM. The specified payload in the GEM 
will be set to the prescribed payload plus one third of the weight 
reduction amount to recognize that approximately one third of the truck 
miles are travelled at maximum payload, as discussed below in the 
payload discussion. The other two thirds of the weight reduction will 
be subtracted from the overall vehicle weight prescribed in the GEM.
    The agencies continue to believe that the 400 pound weight target 
is appropriate to use as a basis for setting the final combination 
tractor CO2 emissions and fuel consumption standards. The 
agencies agree with the commenter that 400 pounds of weight reduction 
without the use of single wide tires may not be achievable for all 
tractor configurations. As noted, the agencies have extended the list 
of weight reduction components in order to provide the manufacturers 
with additional means to comply with the combination tractors and to 
further encourage reductions in vehicle weight. The agencies considered 
increasing the target value beyond 400 pounds given the additional 
reduction potential identified in the expanded technology list; 
however, lacking information on the capacity for the industry to change 
to these lightweight components across the board by the 2014 model 
year, we have decided to maintain the 400 pound target. The agencies 
intend to continue to study the potential for additional weight 
reductions in our future work considering a second phase of vehicle 
fuel efficiency and GHG regulations. In the context of the current 
rulemaking for HD fuel consumption and GHG standards, one would expect 
that reducing the weight of medium-duty trucks similarly would, if 
anything, have a positive impact on safety. However, given the large 
difference in weight between light-duty and medium-duty vehicles, and 
even larger difference between light-duty vehicles and heavy-duty 
vehicles with loads, the agencies believe that the impact of weight 
reductions of medium- and heavy-duty vehicles would not have a 
noticeable impact on safety for any of these classes of vehicles.\85\
---------------------------------------------------------------------------

    \85\ For more information on the estimated safety effects of 
this rule, see Chapter 9 of the RIA.
---------------------------------------------------------------------------

(f) Extended Idle Reduction Technology Assessment
    Extended idling from Class 8 heavy-duty long haul combination 
tractors contributes to significant CO2 emissions and fuel 
consumption in the United States. The Federal Motor Carrier Safety 
Administration regulations require a certain amount of driver rest for 
a corresponding period of driving hours.\86\ Extended idle occurs when 
Class 8 long haul drivers rest in the sleeper cab compartment during 
rest periods as drivers find it both convenient and less expensive to 
rest in the tractor cab itself than to pull off the road and find 
accommodations.\87\ During this rest period a driver will idle the 
tractor engine in order to provide heating or cooling, or to run on-
board appliances. In some cases the engine can idle in excess of 10 
hours. During this period, the engine will consume approximately 0.8 
gallons of fuel and emit over 8,000 grams of CO2 per hour. 
An average tractor engine can consume 8 gallons of fuel and emit over 
80,000 grams of CO2 during overnight idling in such a case.
---------------------------------------------------------------------------

    \86\ Federal Motor Carrier Safety Administration. Hours of 
Service Regulations. Last accessed on August 2, 2010 at http://www.fmcsa.dot.gov/rules-regulations/topics/hos/.
    \87\ The agencies note that some sleeper cabs may be classified 
as vocational tractors and therefore are expected to primarily 
travel locally and would not benefit from an idle reduction 
technology.
---------------------------------------------------------------------------

    Idling reduction technologies (IRT) are available to allow for 
driver comfort while reducing fuel consumptions and CO2 
emissions. Auxiliary power units, fuel operated heaters, battery 
supplied air conditioning, and thermal storage systems are among the 
technologies

[[Page 57154]]

available today. The agencies are adopting a provision for use of 
extended idle reduction technology as an input to the GEM for Class 8 
sleeper cabs. As discussed further in Section III, if a manufacturer 
wishes to receive credit for using IRT to meet the standard, then an 
automatic main engine shutoff must be programmed and enabled, such that 
engine shutdown occurs after 5 minutes of idling, to help ensure the 
reductions are realized in-use. A discussion of the provisions the 
agencies are adopting for allowing an override of this automatic 
shutdown can be found in RIA Chapter 2. As with all of the technology 
inputs discussed in this section, the agencies are not mandating the 
use of idle reductions or idle shutdown, but rather allowing their use 
as one part of a suite of technologies feasible for reducing fuel 
consumption and meeting the final standards and using these 
technologies as the inputs to the GEM. The default value (5 g 
CO2/ton-mile or 0.5 gal/1,000 ton-mile) for the use of 
automatic engine shutdown (AES) with idle reduction technologies was 
determined as the difference between a baseline main engine with idle 
fuel consumption of 0.8 gallons per hour that idles 1,800 hours and 
travels 125,000 miles per year, and a diesel auxiliary power unit 
operating in lieu of main engine during those same idling hours. The 
agencies received various comments from ACEEE and MEMA regarding the 
assumptions used to derive the idle reduction value. ACEEE argued that 
the agencies should use a fuel consumption rate of 0.47 gallon/hour for 
main engine idling based on a paper written by Kahn. MEMA argued that 
the agencies should use a main engine idling fuel consumption rate of 
0.87 gal/hr, which is the midpoint of a DOE calculator reporting fuel 
consumption rates from 0.64 to 1.15 gal/hr at idling conditions, and 
between 800 and 1200 rpm with the air conditioning on and off, 
respectively. The agencies respectfully disagree with the 0.47 gal/hr 
recommendation because the same paper by Kahn shows that while idling 
fuel consumption is 0.47 gal/hr on average at 600 rpm, CO2 
emissions increase by 25 percent with A/C on at 600 rpm, and increase 
by 165 percent between 600 rpm and 1,100 rpm with A/C on.\88\ MEMA 
recommended using 2,500 hours per year for APU operation. They cited 
the SmartWay Web site which uses 2,400 hours per year (8 hours per day 
and 300 days per year). Also, they cited an Argonne study which assumed 
7 hours per day and 303 days per year, which equals 2,121 hours per 
year. Lastly, they referred to the FMCSA 2010 driver guidelines which 
reduce the number of hours driven per day by one to two hours, which 
would lead to 2,650 to 2,900 hours per year. The agencies reviewed 
other studies to quantify idling operations, as discussed in greater 
detail in RIA Section 2.5.4.2, and believe that the entirety of the 
research does not support a change from the proposed calculation. 
Therefore, the agencies are finalizing the calculation as proposed. 
Additional details regarding the comments, calculations, and agency 
decisions are included in RIA Section 2.5.4.2.
---------------------------------------------------------------------------

    \88\ See Gaines, L., A. Vyas, J. Anderson. ``Estimation of Fuel 
Used by Idling Commercial Trucks,'' Page 9 (2006).
---------------------------------------------------------------------------

    The agencies are adopting a provision to allow manufacturers to 
provide an AES system which is active for only a portion of a vehicle's 
life. In this case, a discounted idle reduction value would be entered 
into GEM. A discussion of the calculation of a discounted IRT credit 
can be found in Section III. Additional details on the emission and 
fuel consumption reduction values are included in RIA Section 2.5.4.2.
(g) Vehicle Speed Limiters
    The NPRM proposed to allow combination tractors that use vehicle 
speed limiters (VSL) to include the maximum governed speed value as an 
input to the GEM for purposes of determining compliance with the 
vehicle standards. The agencies also proposed not to assume the use of 
a mandatory vehicle speed limiter because of concerns about how to set 
a realistic application rate that avoids unintended consequences. See 
75 FR at 74223. Governing the top speed of a vehicle can reduce fuel 
consumption and GHG emissions, because fuel consumption and 
CO2 emissions increase proportionally to the square of 
vehicle speed.\89\ Limiting the speed of a vehicle reduces the fuel 
consumed, which in turn reduces the amount of CO2 emitted. 
The specific input to the GEM would be the maximum governed speed limit 
of the VSL that is programmed into the powertrain control module (PCM). 
The agencies stressed in the NPRM that in order to obtain a benefit in 
the GEM, a manufacturer must preset the limiter in such a way that the 
setting will not be ``capable of being easily overridden by the fleet 
or the owner.'' If the top speed could be easily overridden, the fuel 
consumption/CO2 benefits of the VSL might not be realized, 
and the agencies did not want to allow the technology to be used for 
compliance if the technology could be disabled easily and the real 
world benefits not achieved.
---------------------------------------------------------------------------

    \89\ See 2010 NAS Report, Note 21, Page 28. Road Load Force 
Equation defines the aerodynamic portion of the road load as 
[frac12] * Coefficient of Drag * Frontal Area * air density * 
vehicle speed squared.
---------------------------------------------------------------------------

    Both the Center for Biological Diversity (CBD) and New York State 
Department of Transportation and Environmental Conservation commented 
that the application of speed limiters should be used to set the 
tractor standards.\90\ CBD urged the agencies to reconsider the 
position and adopt a speed limitation technology. NY State commented 
that the technologies are cost effective, reduce emissions, and appear 
to be generally acceptable to the trucking industry. They continued to 
say that the vehicle speed limit could be set without compromising 
operational logistics.
---------------------------------------------------------------------------

    \90\ One commenter mistakenly thought that the agencies were 
rejecting consideration of VSLs due to perceived jurisdictional 
obstacles. In fact, both the CAA and EISA allow consideration of VSL 
technology and the agencies considered the appropriateness of basing 
standards on performance of the technology.
---------------------------------------------------------------------------

    Many commenters (Cummins, Daimler, EMA/TMA, ATA, AAPC, NADA) 
supported the use of VSLs as an input to the GEM, but requested 
clarification of what the specific requirements would be to ensure the 
VSL setting would not be capable of being easily overridden. Cummins 
and Daimler requested that the final rules explicitly allow vehicle 
manufacturers to access and adjust the VSL control feature for setting 
the maximum governed speed, arguing that the diverse needs of the 
commercial vehicle industry warrant flexibility in electronic control 
features, and that otherwise supply chain issues \91\ may result from 
the use of VSLs. NADA and EMA/TMA also requested that VSLs have 
override features and be adjustable, citing various needs for 
flexibility by the fleets. EMA/TMA and ATA requested that VSLs be 
adjustable downward by fleets in order to obtain greater benefit in 
GEM, if company policies change or if a subsequent vehicle owner needs 
a different VSL setting. EMA/TMA stated that the agencies should 
prohibit tampering with VSLs, and both EMA and TRALA requested more 
information on how the agencies intended to address tampering with 
VSLs.
---------------------------------------------------------------------------

    \91\ Commenters stated that OEMs need access for setting 
appropriate trims for managing the VSL, otherwise significant supply 
chain issues could result such as parts shortages caused by the need 
for unique speed governed PCMs.
---------------------------------------------------------------------------

    In addition to features governing the maximum vehicle speed, 
commenters requested adding other programmable flexibilities to 
mitigate potential drawbacks to VSLs. Cummins, DTNA,

[[Page 57155]]

and EMA/TMA requested that a programmable ``soft top'' speed be added 
to PCMs which would allow a vehicle to exceed the speed limit setting 
governed by a VSL for a short period of time. A ``soft top'' feature 
could be used for a limited duration in order to maneuver and pass 
other on-road vehicles at speeds greater than that governed by the VSL. 
The commenters argued this was important for vehicle passing and 
safety-related situations where, without a soft top feature, it could 
be possible for speed limited trucks to obstruct other vehicles on the 
road and cause severe road congestion.
    ATA and EMA/TMA also requested that manufacturers be allowed to 
program a mileage based expiration into the VSL control feature, in 
order to preserve the value of vehicles for second owners who may 
require operation at higher speeds. ATA further commented that 
manufacturers should be allowed to account for additional GEM input 
benefits if the speed governor is reprogrammed to a lower speed within 
the useful life of the vehicle.
    After carefully considering the comments, the agencies have 
decided, for these final rules, to retain most of the elements in the 
proposal. Manufacturers will be allowed to implement a fixed maximum 
governed vehicle speed through a VSL feature and to use the maximum 
governed vehicle speed as an input to the GEM for certification. Also 
consistent with the proposal, the agencies are not premising the final 
standards on the use of VSLs. The comments received from stakeholders 
did not address the agencies' concerns discussed in the proposal, 
specifically the risk of requiring VSL in situations that are not 
appropriate from an efficiency perspective because it may lead to 
additional vehicle trips to deliver the same amount of freight.\92\ The 
agencies continue to believe that we are not in a position to determine 
how many additional vehicles would benefit from the use of a VSL with a 
setting of less than 65 mph (a VSL with a speed set at or above 65 mph 
will show no CO2 emissions or fuel consumption benefit on 
the drive cycles included in this program). The agencies further 
believe that manufacturers will not utilize VSLs unless it is in their 
interest to do so, so that these unintended consequences should not 
occur when manufacturers use VSLs as a compliance strategy. We will 
monitor the industry's use of VSL in this program and may consider 
using this technology in standard setting in the future.
---------------------------------------------------------------------------

    \92\ See 75 FR at page 74223.
---------------------------------------------------------------------------

    The agencies have decided to adopt commenters' suggestions to allow 
adjustable lower limits that can be set and governed by VSLs 
independent of the one governing the maximum certified speed limit to 
provide the desired flexibility requested by the trucking industry. We 
believe that this flexibility would not decrease the anticipated fuel 
consumption or CO2 benefits of VSLs because the adjustable 
limits would be lower values. Issues identified by the commenters 
including the ability to change delivery routes requiring lower 
governed speeds or when a fleet's business practices change resulting 
in a desire for greater fuel consumption savings are not in conflict 
with the purpose and benefit of VSLs. As such, the agencies have 
decided to allow a manufacturer to install features for its fleet 
customers to set their own lower adjustable limits below the maximum 
VSL specified by the agencies. However, the agencies have decided to 
not allow any additional benefit in the GEM to a manufacturer for 
allowing a lower governed speed in-use than the certified maximum limit 
for this first phase of the HD National Program because we can only be 
certain that the VSL will be at the maximum setting.
    Both agencies also agree that manufacturers can provide a ``soft 
top'' and expiration features to be programmed into PCMs to provide 
additional flexibility for fleet owners and so that fleets who purchase 
used vehicles have the ability to have different VSL policies than the 
original owner of the vehicle. Although the agencies considered 
limiting the soft top maximum level due to safety and fuel consumption/
GHG benefit concerns, we have decided to allow the soft top maximum 
level to be set to any level higher than the maximum speed governed by 
the VSL. This approach will provide drivers with the ability to better 
navigate through traffic. However, the agencies are requiring that 
manufacturers providing a soft top feature must design the system so it 
cannot be modified by the fleets and will not decrement the vehicle 
speed limit causing the vehicle to decelerate while the driver is 
operating a vehicle above the normal governed vehicle speed limit. For 
example, if a manufacturer designs a vehicle speed limiter that has a 
normal governed speed limiter setting of 62 mph, and a ``soft top'' 
speed limiter value of 65 mph, the algorithm shall not cause the 
vehicle speed to decrement causing the vehicle to decelerate while the 
driver is operating the vehicle at a speed greater that 62 mph (between 
62 and 65 mph). The agencies are concerned that a forced deceleration 
when a driver is attempting to pass or maneuver could have an adverse 
impact on safety.
    In using a soft top feature, a manufacturer will be required to 
provide to the agencies a functional description of the ``soft top'' 
control strategy including calibration values, the speed setting for 
both the hard limit and the soft top and the maximum time per day the 
control strategy could allow the vehicle to operate at the ``soft top'' 
speed limit at the time of certification. This information will be used 
to derive a factor to discount the VSL input used in the GEM to 
determine the fuel consumption and GHG emissions performance of the 
vehicle. The agencies also agree with comments that VSLs should be 
adjustable so as not to potentially limit a vehicle's resale value. 
However, manufacturers choosing the option to override the VSL after a 
specified number of miles would be required to discount the benefit of 
the VSL relative to the tractor's full lifetime miles. The VSL discount 
benefits for using soft-top and expiration features must be calculated 
using Equation II-1.\93\ Additional details regarding the derivation of 
the discounted equation are included in RIA Chapter 2. The agencies are 
also requiring that any vehicle that has a ``soft top'' VSL to identify 
the use of the ``soft top'' VSL on the vehicle emissions label.
---------------------------------------------------------------------------

    \93\ See Sec.  1037.640.
---------------------------------------------------------------------------

Equation II-1: Discounted Vehicle Speed Limiter Equation

VSL input for GEM = Expiration Factor * [Soft Top Factor* Soft Top VSL 
+ (1-Soft Top Factor) * VSL] + (1-Expiration Factor)*65 mph
    The agencies will require that the VSL algorithm be designed to 
assure that over the useful life of the vehicle that the vehicle will 
not operate in the soft top mode for more miles than would be expected 
based on the values used in Equation 0-1, as specified by the 
expiration factor and the soft top factor. In addition, any time the 
cumulative percentage of operation in the soft top mode (based on 
miles) exceeds the maximum ratio that could occur at the full lifetime 
mileage, or at the expiration mileage if used, the algorithm must not 
allow the vehicle to exceed the VSL value. In this case, the soft top 
feature remain disabled until the vehicle mileage reaches a point where 
the ratio no longer meets this condition.
    In response to the comments about how the agencies will evaluate

[[Page 57156]]

tampering, NHTSA and EPA have added a number of requirements in these 
final rules relating to the VSL control feature. VSL control features 
should be designed so they cannot be easily overridden. Manufacturers 
must ensure that the governed speed limit programmed into the VSL must 
also be verifiable through on-board diagnostic scanning tools, and must 
provide a description of the coding to identify the governed maximum 
speed limit and the expiration mileage both at the time of the initial 
vehicle certification and in-use. The agencies believe both 
manufacturers and fleets should work toward maintaining the integrity 
of VSLs, and the agencies may conduct new-vehicle and in-use random 
audits to verify that inputs into GEM are accurate.
    The agencies are aware that some fleets/owners make changes to 
vehicles, such as installing different diameter tires, changing the 
axle (final drive) ratio and transmission gearing, such that a vehicle 
could travel at speeds higher than the speed limited by its VSL. 
Vehicles subject to FMCSA requirements must be in compliance with 49 
CFR 393.82. The requirements apply to speedometers and states as 
follows:

    Each bus, truck, and truck-tractor must be equipped with a 
speedometer indicating vehicle speed in miles per hour and/or 
kilometers per hour. The speedometer must be accurate to within plus 
or minus 8 km/hr (5 mph) at a speed of 80 km/hr (50 mph).

    To facilitate adjustments for component changes affecting vehicle 
speed, manufacturers should provide a fleet/owner with the means to do 
so unless the adjustments would affect the VSL setting or operation.
    DTNA and ATA additionally requested that the agencies ensure that 
any VSL provisions adopted under the GHG emissions and fuel efficiency 
rules align with existing NHTSA standards. The agencies agree and note 
that there are no existing standards for a VSL outside of this current 
rulemaking activity. However, NHTSA has announced its intent to publish 
a proposal in 2012 for a VSL.\94\ While both agencies have taken steps 
to avoid potential conflicts between the rulemaking being finalized 
today for fuel consumption and GHG emissions and the anticipated safety 
rulemaking, different conclusions may be reached in a safety-based 
rulemaking on VSLs, particularly in the approach to specifying soft top 
parameters and VSL expiration.
---------------------------------------------------------------------------

    \94\ 76 FR 78.
---------------------------------------------------------------------------

(h) Defined Vehicle Configurations in the GEM
    As discussed above, the agencies are adopting methodologies that 
manufacturers will use to quantify the values input into the GEM for 
these factors affecting vehicle efficiency: Coefficient of Drag, Tire 
Rolling Resistance Coefficient, Weight Reduction, Vehicle Speed 
Limiter, and Extended Idle Reduction Technology. The other aspects of 
the vehicle configuration are fixed within the model and are not varied 
for the purpose of compliance. The defined inputs include the tractor-
trailer combination curb weight, payload, engine characteristics, and 
drivetrain for each vehicle type, and others.
(i) Vehicle Drive Cycles
    The GEM simulation model uses various inputs to characterize a 
vehicle's configuration (such as weight, aerodynamics, and rolling 
resistance) and predicts how the vehicle would behave on the road when 
it follows a driving cycle (vehicle speed versus time). As noted by the 
2010 NAS Report,\95\ the choice of a drive cycle used in compliance 
testing has significant consequences on the technology that will be 
employed to achieve a standard as well as the ability of the technology 
to achieve real world reductions in emissions and improvements in fuel 
consumption. Manufacturers naturally will design vehicles to ensure 
they satisfy regulatory standards. An ill-suited drive cycle for a 
regulatory category could encourage GHG emissions and fuel consumption 
technologies which satisfy the test but do not achieve the same 
benefits in use. For example, requiring all trucks to use a constant 
speed highway drive cycle will drive significant aerodynamic 
improvements. However, in the real world a combination tractor used for 
local delivery may spend little time on the highway, reducing the 
benefits achieved by this technology. In addition, the extra weight of 
the aerodynamic fairings will actually penalize the GHG and fuel 
consumption performance in urban driving and may reduce the freight 
carrying capability. The unique nature of the kinds of CO2 
emissions control and fuel consumption technology means that the same 
technology can be of benefit during some operation but cause a reduced 
benefit under other operation.\96\ To maximize the GHG emissions and 
fuel consumption benefits and avoid unintended reductions in benefits, 
the drive cycle should focus on promoting technology that produces 
benefits during the primary operation modes of the application. 
Consequently, drive cycles used in GHG emissions and fuel consumption 
compliance testing should reasonably represent the primary actual use, 
notwithstanding that every vehicle has a different drive cycle in-use.
---------------------------------------------------------------------------

    \95\ See 2010 NAS Report, Note 21, Chapters 4 and 8.
    \96\ This situation does not typically occur for heavy-duty 
emission control technology designed to control criteria pollutants 
such as PM and NOX.
---------------------------------------------------------------------------

    The agencies proposed a modified version of the California ARB 
Heavy Heavy-duty Truck 5 Mode Cycle \97\, using the basis of three of 
the cycles which best mirror Class 7 and 8 combination tractor driving 
patterns, based on information from EPA's MOVES model.\98\ The key 
advantage of the California ARB 5 mode cycle is that it provides the 
flexibility to use several different modes and weight the modes to fit 
specific vehicle application usage patterns. For the proposal, EPA 
analyzed the five cycles and found that some modifications to the 
cycles were required to allow sufficient flexibility in weightings. The 
agencies proposed the use of the Transient mode, as defined by 
California ARB, because it broadly covers urban driving. The agencies 
also proposed altered versions of the High Speed Cruise and Low Speed 
Cruise modes which reflected only constant speed cycles at 65 mph and 
55 mph respectively. In the NPRM, the agencies proposed to use three 
cycles which were the ARB transient cycle, a 55 mph steady state 
cruise, and a 65 mph steady state cruise.
---------------------------------------------------------------------------

    \97\ California Air Resources Board. Heavy Heavy-duty Diesel 
Truck chassis dynamometer schedule, Transient Mode. Last accessed on 
August 2, 2010 at http://www.dieselnet.com/standards/cycles/hhddt.html.
    \98\ EPA's MOVES (Motor Vehicle Emission Simulator). See http://www.epa.gov/otaq/models/moves/index.htm for additional information.
---------------------------------------------------------------------------

    The agencies received comment from NACAA recommending an increase 
in the high speed cruise cycle speed from the proposed value of 65 mph 
to 75 mph because trucks travel at higher speeds. The agencies analyzed 
the urban and rural interstate truck speed limits in each state to 
determine the national average truck speed limit. State interstate 
speed limits for trucks vary between 55 and 75 mph, depending on the 
state.\99\ Based on this information, the national median truck speed 
limit is

[[Page 57157]]

65 mph. The agencies also analyzed the national average truck speed 
limit weighted by VMT for each state based on VMT data by state from 
the Federal Highway Administration as described in RIA Section 3.4.2. 
Based on this information, the national average VMT-weighted truck 
speed limit is 63 mph. The agencies continue to believe that the 
appropriate high speed cruise speed should be set at the national 
average truck speed limit to appropriately balance the evaluation of 
technologies such as aerodynamics, but not overstate the benefits of 
these technologies. Therefore, the agencies are adopting as proposed a 
speed of 65 mph for the high speed cruise cycle.
---------------------------------------------------------------------------

    \99\ Governors Highway Safety Association. Speed Limit Laws May 
2011. Last viewed on May 9, 2011 at http://www.ghsa.org/html/stateinfo/laws/speedlimit_laws.html.
---------------------------------------------------------------------------

    The agencies also received comments from Allison which disagreed 
with proposed drive cycles for combination tractors because the cycles 
did not account for external factors such as grades, wind, traffic 
condition, etc. Allison also believes that the acceleration rates are 
too low. The agencies recognize that the proposed drive cycles do not 
incorporate the external factors described by Allison. Parallel to the 
approach used to evaluate light-duty vehicles, the drive cycles do not 
incorporate either grade or wind which can be difficult to simulate in 
chassis dynamometer cells. In the final rules, the agencies are 
defining an approach that manufacturers may take to evaluate their 
aerodynamic packages in a wind-averaged condition and use a modified Cd 
value in GEM.\100\ The agencies are also adopting provisions for the 
innovative technology demonstration that allows for the use of on-road 
testing which includes grades for technologies whose benefits are 
reflected with grade. Lastly, the agencies' final drive cycles for 
highway operation contain a constant speed, as proposed. The 
acceleration and deceleration rates are only used to bring the vehicle 
to the cruising speed and the CO2 emissions and fuel 
consumption from these portions of the drive cycle are not included in 
the composite emissions and fuel consumption results. The agencies did 
not include the speed dithering, which is representative of actual 
driving and traffic conditions, in the proposed constant speed portion 
of the cycles because the dithering does not provide any additional 
distinction between technologies but only added complexity to the 
cycle. The agencies believe this approach is still appropriate for the 
final action.
---------------------------------------------------------------------------

    \100\ See Section IV.B.3.b below.
---------------------------------------------------------------------------

    Allison referred the agencies to the Oak Ridge National Laboratory 
and SmartWay program to review the amount of time long-haul vehicles 
spend on the highway. They believe the steady state highway speeds are 
overestimated. Data provided by Allison indicates that day cabs spend 
only 14 percent of miles traveling at speeds greater than 60 mph. NHTSA 
and EPA recognize that there is a variation in the amount of miles day 
cabs travel under different operations. As described above, the 
agencies are adopting an approach where tractors which operate like 
vocational vehicles may be regulated as such in the HD program. Thus, 
these day cabs will have a drive cycle weighting representative of 
vocational vehicles with more weighting on the transient operation and 
less on the highway speed operation.
    For proposal, EPA and NHTSA relied on the EPA MOVES analysis of 
Federal Highway Administration data to develop the mode weightings to 
characterize typical operations of heavy-duty trucks, per Table II-10 
below.\101\ A detailed discussion of drive cycles is included in RIA 
Chapter 3.\102\ The agencies are adopting the proposed drive cycle 
weightings for combination tractors.
---------------------------------------------------------------------------

    \101\ The Environmental Protection Agency. Draft MOVES2009 
Highway Vehicle Population and Activity Data. EPA-420-P-09-001, 
August 2009 http://www.epa.gov/otaq/models/moves/techdocs/420p09001.pdf.
    \102\ In the light-duty vehicle rule, EPA and NHTSA based 
compliance with tailpipe standards on use of the FTP and HFET, and 
declined to use alternative tests. See 75 FR 25407. NHTSA is 
mandated to use the FTP and HFET tests for CAFE standards, and all 
relevant data was obtained by FTP and HFET testing in any case. Id. 
Neither of these constraints exists for Class 7-8 tractors. The 
little data which exist on current performance are principally 
measured by the ARB Heavy Heavy-duty Truck 5 Mode Cycle testing, and 
NHTSA is not mandated to use the FTP to establish heavy-duty fuel 
economy standards. See 49 U.S.C. 32902(k)(2) authorizing NHTSA, 
among other things, to adopt and implement appropriate ``test 
methods, measurement metrics, * * * and compliance protocols''.

                Table II-10--Drive Cycle Mode Weightings
------------------------------------------------------------------------
                                                   55 mph       65 mph
                                    Transient      cruise       cruise
------------------------------------------------------------------------
Day Cabs.........................          19%          17%          64%
Sleeper Cabs.....................           5%           9%          86%
------------------------------------------------------------------------

(ii) Standardized Trailers
    As proposed, NHTSA and EPA are adopting provisions so that the 
tractor performance in the GEM is judged assuming the tractor is 
pulling a standardized trailer. The agencies did not receive any 
adverse comments related to this approach. The agencies believe that an 
assessment of the tractor fuel consumption and CO2 emissions 
should be conducted using a tractor-trailer combination. We believe 
this approach best reflects the impact of the overall weight of the 
tractor-trailer and the aerodynamic technologies in actual use, where 
tractors are designed and used with a trailer. The GEM will continue to 
use a predefined typical trailer in assessing overall performance. The 
high roof sleeper cabs are paired with a standard box trailer; the mid 
roof tractors are paired with a tanker trailer; and the low roof 
tractors are paired with a flat bed trailer.
(iii) Empty Weight and Payload
    The total weight of the tractor-trailer combination is the sum of 
the tractor curb weight, the trailer curb weight, and the payload. The 
total weight of a vehicle is important because it in part determines 
the impact of technologies, such as rolling resistance, on GHG 
emissions and fuel consumption. In this final action, the agencies are 
specifying each of these aspects of the vehicle, as proposed.
    In use, trucks operate at different weights at different times 
during their operations. The greatest freight transport efficiency (the 
amount of fuel required to move a ton of payload) would be achieved by 
operating trucks at the maximum load for which they are designed all of 
the time. However, logistics such as delivery demands which require 
that trucks travel without full loads, the density of payload, and the 
availability of full loads of freight limit the ability of trucks to 
operate at their highest efficiency all the time. M.J. Bradley analyzed 
the Truck Inventory and Use Survey and found that

[[Page 57158]]

approximately 9 percent of combination tractor miles travelled empty, 
61 percent are ``cubed-out'' (the trailer is full before the weight 
limit is reached), and 30 percent are ``weighed out'' (operating weight 
equal 80,000 pounds which is the gross vehicle weight limit on the 
Federal Interstate Highway System or greater than 80,000 pounds for 
vehicles traveling on roads outside of the interstate system).\103\
---------------------------------------------------------------------------

    \103\ M.J. Bradley & Associates. Setting the Stage for 
Regulation of Heavy-Duty Vehicle Fuel Economy and GHG Emissions: 
Issues and Opportunities. February 2009. Page 35. Analysis based on 
1992 Truck Inventory and Use Survey data, where the survey data 
allowed developing the distribution of loads instead of merely the 
average loads.
---------------------------------------------------------------------------

    As described above, the amount of payload that a tractor can carry 
depends on the category (or GVWR and GCWR) of the vehicle. For example, 
a typical Class 7 tractor can carry less payload than a Class 8 
tractor. For proposal, the agencies used the Federal Highway 
Administration Truck Payload Equivalent Factors using Vehicle Inventory 
and Use Survey (VIUS) and Vehicle Travel Information System data to 
determine the proposed payloads. FHWA's results found that the average 
payload of a Class 8 vehicle ranged from 36,247 to 40,089 pounds, 
depending on the average distance travelled per day.\104\ The same 
results found that Class 7 vehicles carried between 18,674 and 34,210 
pounds of payload also depending on average distance travelled per day. 
Based on this data, the agencies proposed to prescribe a fixed payload 
of 25,000 pounds for Class 7 tractors and 38,000 pounds for Class 8 
tractors for their respective test procedures. The agencies proposed a 
common payload for Class 8 day cabs and sleeper cabs as predefined GEM 
input because the data available do not distinguish based on type of 
Class 8 tractor. These payload values represent a heavily loaded 
trailer, but not maximum GVWR, since as described above the majority of 
tractors ``cube-out'' rather than ``weigh-out.''
---------------------------------------------------------------------------

    \104\ The U.S. Federal Highway Administration. Development of 
Truck Payload Equivalent Factor. Table 11. Last viewed on March 9, 
2010 at http://ops.fhwa.dot.gov/freight/freight_analysis/faf/faf2_reports/reports9/s510_11_12_tables.htm.
---------------------------------------------------------------------------

    The agencies developed the proposed tractor curb weight inputs from 
actual tractor weights measured in two of EPA's test programs and based 
on information from the manufacturers. The proposed trailer curb weight 
inputs were derived from actual trailer weight measurements conducted 
by EPA and weight data provided to ICF International by the trailer 
manufacturers.\105\
---------------------------------------------------------------------------

    \105\ ICF International. Investigation of Costs for Strategies 
to Reduce Greenhouse Gas Emissions for Heavy-Duty On-road Vehicles. 
July 2010. Pages 4-15. Docket Number EPA-HQ-OAR-2010-0162-0044.
---------------------------------------------------------------------------

    The agencies received comments from UMTRI and ATA regarding the 
values assumed for the combination tractor weights. UMTRI recommended 
using 80,000 pounds for the total weight for tractor-trailer 
combinations. ATA based on their analysis of the Federal Highway 
Administration's Long Term Pavement Database, recommended 5,000 to 
10,000 pound payload for Class 7 tractors and 25,000 to 30,000 pounds 
for Class 8 tractors. ATA also determined from the same database that 
20 percent of tractor miles are empty, 67 percent cube-out, and 13 
percent weigh-out. The agencies are adopting the proposed tractor-
trailer weights because we do not have strong evidence to select other 
values and because changing the assumed values would not change the 
impact on GHG emissions or fuel consumption of the technologies 
included in this phase of the HD program (the relative stringency of 
the standards and the projected emission reductions do not change with 
assumed payload). NHTSA and EPA intend to continue evaluating 
additional sources of weight information in future phases of the 
program.
    Details of the final individual weight inputs by regulatory 
category, as shown in Table II-11, are included in RIA Chapter 3.

                                 Table II-11--Final Combination Tractor Weights
----------------------------------------------------------------------------------------------------------------
                                                                Tractor      Trailer                    Total
             Model type               Regulatory subcategory  tare weight     weight      Payload       weight
                                                                 (lbs)        (lbs)        (lbs)        (lbs)
----------------------------------------------------------------------------------------------------------------
Class 8.............................  Sleeper Cab High Roof.       19,000       13,500       38,000       70,500
Class 8.............................  Sleeper Cab Mid Roof..       18,750       10,000       38,000       66,750
Class 8.............................  Sleeper Cab Low Roof..       18,500       10,500       38,000       67,000
Class 8.............................  Day Cab High Roof.....       17,500       13,500       38,000       69,000
Class 8.............................  Day Cab Mid Roof......       17,100       10,000       38,000       65,100
Class 8.............................  Day Cab Low Roof......       17,000       10,500       38,000       65,500
Class 7.............................  Day Cab High Roof.....       11,500       13,500       25,000       50,000
Class 7.............................  Day Cab Mid Roof......       11,100       10,000       25,000       46,100
Class 7.............................  Day Cab Low Roof......       11,000       10,500       25,000       46,500
----------------------------------------------------------------------------------------------------------------

(iv) Standardized Drivetrain
    The agencies' assessment at proposal of the current vehicle 
configuration process at the truck dealer's level was that the truck 
companies provide tools to specify the proper drivetrain matched to the 
buyer's specific circumstances. These dealer tools allow a significant 
amount of customization for drive cycle and payload to provide the best 
specification for each individual customer. The agencies are not 
seeking to disrupt this process. Optimal drivetrain selection is 
dependent on the engine, drive cycle (including vehicle speed and road 
grade), and payload. Each combination of engine, drive cycle, and 
payload has a single optimal transmission and final drive ratio. The 
agencies received comments from ArvinMeritor and ICCT which suggested 
that the agencies incorporate the actual drivetrain configuration (axle 
configuration, driveline efficiency, and transmission) into the GEM. 
The agencies continue to believe, and therefore are adopting as 
proposed, that it is appropriate to specify the engine's fuel 
consumption map, drive cycle, and payload; therefore, it makes sense to 
also specify the drivetrain that matches.
(v) Engine Input to the GEM for Tractors
    As proposed, the agencies are defining the engine characteristics 
used in the GEM, including the fuel consumption map which provides the 
fuel consumption at hundreds of engine speed and torque points. If the 
agencies did not standardize the fuel map, then a tractor that uses an 
engine with emissions and fuel consumption better than the standards 
would require fewer vehicle reductions than those technically feasible 
reductions reflected in the final standards. The agencies are 
finalizing two distinct fuel consumption maps for use in the GEM. The 
first fuel

[[Page 57159]]

consumption map would be used in the GEM for the 2014 through 2016 
model years and represents an average engine which meets EPA's final 
2014 model year engine CO2 emissions standards. The same 
fuel map would be used for NHTSA's voluntary standards in the 2014 and 
2015 model years, as well as its mandatory program in the 2016 model 
year. A second fuel consumption map will be used beginning in the 2017 
model year and represents an engine which meets the 2017 model year 
CO2 emissions and fuel consumption standards and accounts 
for the increased stringency in the final MY 2017 standard. The 
agencies have modified the 2017 MY fuel map used in the GEM for the 
final rulemaking to address comments received. Details regarding this 
change can be found in RIA Chapter 4.4.4. Effectively there is no 
change in stringency of the tractor vehicle (not including the engine 
standards over the full rulemaking period).\106\ These inputs are 
appropriate given the separate regulatory requirement that Class 7 and 
8 combination tractor manufacturers use only certified engines.
---------------------------------------------------------------------------

    \106\ As noted earlier, use of the 2017 model year fuel 
consumption map as a GEM input results in numerically more stringent 
final vehicle standards for MY 2017.
---------------------------------------------------------------------------

(i) Heavy-Duty Engine Test Procedure for Engines Installed in 
Combination Tractors
    The HD engine test procedure consists of two primary aspects--a 
duty cycle and a metric to evaluate the emissions and fuel consumption.
    EPA proposed that the GHG emission standards for heavy-duty engines 
under the CAA would be expressed as g/bhp-hr while NHTSA's proposed 
fuel consumption standards under EISA, in turn, be represented as gal/
100 bhp-hr. The NAS panel did not specifically discuss or recommend a 
metric to evaluate the fuel consumption of heavy-duty engines. However, 
as noted above they did recommend the use of a load-specific fuel 
consumption metric for the evaluation of vehicles.\107\ An analogous 
metric for engines is the amount of fuel consumed per unit of work. The 
g/bhp-hr metric is also consistent with EPA's current standards for 
non-GHG emissions for these engines. The agencies did not receive any 
adverse comments related to the metrics for HD engines; therefore, we 
are adopting the metrics as proposed.
---------------------------------------------------------------------------

    \107\ See NAS Report, Note 21, at page 39.
---------------------------------------------------------------------------

    The agencies believe it is appropriate to set standards based on a 
single test procedure, either the Heavy-duty FTP or SET, depending on 
the primary expected use of the engine. This approach differs from 
EPA's criteria pollutant standards for engines which currently require 
that manufacturers demonstrate compliance over the transient FTP cycle; 
over the steady-state SET procedure; and during not-to-exceed testing. 
EPA created this multi-layered approach to criteria emissions control 
in response to engine designs that optimized operation for lowest fuel 
consumption at the expense of very high criteria emissions when 
operated off the regulatory cycle. EPA's use of multiple test 
procedures for criteria pollutants helps to ensure that manufacturers 
calibrate engine systems for compliance under all operating conditions. 
We are not concerned if manufacturers further calibrate engines off-
cycle to give better in-use fuel consumption while maintaining 
compliance with the criteria emissions standards as such calibration is 
entirely consistent with the goals of our joint program. Further, we 
believe that setting GHG and fuel consumption standards based on both 
transient and steady-state operating conditions for all engines could 
lead to undesirable outcomes.
    It is critical to set standards based on the most representative 
test cycles in order for performance in-use to obtain the intended (and 
feasible) air quality and fuel consumption benefits. Tractors spend the 
majority of their operation at steady state conditions, and will obtain 
in-use benefit of technologies such as turbocompounding and other waste 
heat recovery technologies during this kind of typical engine 
operation. Turbocompounding is a very effective approach to lower fuel 
consumption under steady driving conditions typified by combination 
tractor trailer operation and is well reflected in testing over the SET 
test procedure. However, when used in driving typified by transient 
operation as we expect for vocational vehicles and as is represented by 
the Heavy-duty FTP, turbocompounding shows very little benefit. Setting 
an emission standard based on the Heavy-duty FTP for engines intended 
for use in combination tractor trailers could lead manufacturers to not 
apply turbocompounding even though it can be a highly cost effective 
means to reduce GHG emissions and lower fuel consumption. (It is for 
this reason that turbocompounding is not part of the technology basis 
for MHD or HHD engines installed in vocational vehicles.)
    The agencies proposed that engines installed in tractors 
demonstrate compliance with the CO2 emissions and fuel 
consumption standards over the SET cycle. Commenters such as Cummins, 
Bosch, Daimler, and Honeywell supported the proposed approach. ACEEE 
recommended adopting a new test cycle, such as the World Harmonized 
Duty Cycle which was developed using newer data, to evaluate HD 
engines. Daimler also supported the WHDC for future phases of the 
program. The agencies continue to believe the important issues and 
technical work related to setting new criteria pollutant emissions 
standards appropriate for the World Harmonized Duty Cycle are 
significant and beyond the scope of this rulemaking. The SET cycle 
remains representative of typical driving cycles for combination 
tractors (and engines installed in them). Therefore, the agencies are 
adopting the SET cycle to evaluate CO2 emissions and fuel 
consumption of HD engines installed in tractors, as proposed.
    The current non-GHG emissions engine test procedures also require 
the development of regeneration emission rates and frequency factors to 
account for the emission changes during a regeneration event (40 CFR 
86.004-28). EPA and NHTSA proposed not to include these emissions from 
the calculation of the compliance levels over the defined test 
procedures. Cummins and Daimler supported this approach and stated that 
sufficient incentives already exist for manufacturers to limit 
regeneration frequency. Conversely, Volvo opposed the omission of IRAF 
requirements for CO2 emissions because emissions from 
regeneration can be a significant portion of the expected improvement 
and a significant variable between manufacturers
    At proposal, we considered including regeneration in the estimate 
of fuel consumption and GHG emissions and decided not to do so for two 
reasons. See 75 FR at 74188. First, EPA's existing criteria emission 
regulations already provide a strong motivation to engine manufacturers 
to reduce the frequency and duration of infrequent regeneration events. 
The very stringent 2010 NOX emission standards cannot be met 
by engine designs that lead to frequent and extend regeneration events. 
Hence, we believe engine manufacturers are already reducing 
regeneration emissions to the greatest degree possible. In addition to 
believing that regenerations are already controlled to the extent 
technologically possible, we believe that attempting to include 
regeneration emissions in the standard setting could lead to an 
inadvertently lax emissions standard. In order to include regeneration 
and set appropriate standards, EPA and NHTSA would have needed to 
project the regeneration

[[Page 57160]]

frequency and duration of future engine designs in the time frame of 
this program. Such a projection would be inherently difficult to make 
and quite likely would underestimate the progress engine manufacturers 
will make in reducing infrequent regenerations. If we underestimated 
that progress, we would effectively be setting a more lax set of 
standards than otherwise would be expected. Hence in setting a standard 
including regeneration emissions we faced the real possibility that we 
would achieve less effective CO2 emissions control and fuel 
consumption reductions than we will achieve by not including 
regeneration emissions. Therefore, the agencies are finalizing an 
approach as proposed which does not include the regenerative emissions.
(j) Chassis-Based Test Procedure
    In the proposal, the agencies considered proposing a chassis-based 
vehicle test to evaluate Class 7 and 8 tractors based on a laboratory 
test of the engine and vehicle together. A ``chassis dynamometer test'' 
for heavy-duty vehicles would be similar to the Federal Test Procedure 
used today for light-duty vehicles.
    However, the agencies decided not to propose the use of a chassis 
test procedure to demonstrate compliance for tractor standards due to 
the significant technical hurdles to implementing such a program by the 
2014 model year. The agencies recognize that such testing requires 
expensive, specialized equipment that is not yet widespread within the 
industry. The agencies have only identified approximately 11 heavy-duty 
chassis sites in the United States today and rapid installation of new 
facilities to comply with model year 2014 is not possible.\108\
---------------------------------------------------------------------------

    \108\ For comparison, engine manufacturers typically own a large 
number of engine dynamometer test cells for engine development and 
durability (up to 100 engine dynamometers per manufacturer).
---------------------------------------------------------------------------

    In addition, and of equal if not greater importance, because of the 
enormous numbers of vehicle configurations that have an impact on fuel 
consumption, we do not believe that it would be reasonable to require 
testing of many combinations of tractor model configurations on a 
chassis dynamometer. The agencies evaluated the options available for 
one tractor model (provided as confidential business information from a 
truck manufacturer) and found that the company offered three cab 
configurations, six axle configurations, five front axles, 12 rear 
axles, 19 axle ratios, eight engines, 17 transmissions, and six tire 
sizes--where each of these options could impact the fuel consumption 
and CO2 emissions of the tractor. Even using representative 
grouping of tractors for purposes of certification, this presents the 
potential for many different combinations that would need to be tested 
if a standard were adopted based on a chassis test procedure.
    The agencies received comments from ACEEE and UCS supporting a full 
vehicle testing approach, but these commenters recognized the 
difficulties in doing this in the first phase of the HD program. The 
agencies maintain that the full vehicle testing on chassis dynamometers 
is not feasible in the timeframe of this rulemaking, although we 
believe such an approach may be appropriate in the future, if more 
testing facilities become available and if the agencies are able to 
address the complexity of tractor configurations issue described above.
(4) Summary of Flexibility and Credit Provisions for Tractors and 
Engine Used in These Tractors
    EPA and NHTSA are finalizing four flexibility provisions 
specifically for heavy-duty tractor and engine manufacturers, as 
discussed in Section IV below. These are an averaging, banking and 
trading program for emissions and fuel consumption credits, as well as 
provisions for early credits, advanced technology credits, and credits 
for innovative vehicle or engine technologies which are not included as 
inputs to the GEM or are not demonstrated on the engine SET test cycle. 
With the exception of the advanced technology credits, credits 
generated under these provisions can only be used within the same 
averaging set which generated the credit (for example, credits 
generated by HD engines installed in tractors can only be used by HD 
engines). EPA is also adopting a N2O emission credit 
program, as described in Section IV below.
(5) Deferral of Standards for Tractor and Engine Manufacturing 
Companies That Are Small Businesses
    EPA and NHTSA are not adopting greenhouse gas emissions and fuel 
consumption standards for small tractor or engine manufacturers meeting 
the Small Business Administration (SBA) size criteria of a small 
business as described in 13 CFR 121.201.\109\ The agencies will instead 
consider appropriate GHG and fuel consumption standards for these 
entities as part of a future regulatory action. This includes both 
U.S.-based and foreign small volume heavy-duty tractor and engine 
manufacturers.
---------------------------------------------------------------------------

    \109\ See Sec.  1036.150 and Sec.  1037.150.
---------------------------------------------------------------------------

    The agencies have identified two entities that fit the SBA size 
criterion of a small business.\110\ The agencies estimate that these 
small entities comprise less than 0.5 percent of the total heavy-duty 
combination tractors in the United States based on Polk Registration 
Data from 2003 through 2007,\111\ and therefore that the exemption will 
have a negligible impact on the GHG emissions and fuel consumption 
improvements from the final standards.
---------------------------------------------------------------------------

    \110\ The agencies have identified Ottawa Truck, Inc. and Kalmar 
Industries USA as two potential small tractor manufacturers.
    \111\ M.J. Bradley. Heavy-duty Vehicle Market Analysis. May 
2009.
---------------------------------------------------------------------------

    To ensure that the agencies are aware of which companies would be 
exempt, we are requiring that such entities submit a declaration to EPA 
and NHTSA containing a detailed written description of how that 
manufacturer qualifies as a small entity under the provisions of 13 CFR 
121.201.

C. Heavy-Duty Pickup Trucks and Vans

    The primary elements of the EPA and NHTSA programs for complete HD 
pickups and vans are presented in this section. These provisions also 
cover optional chassis certification of incomplete HD vehicles and of 
Class 4 and 5 vehicles, as discussed in detail in Section V.B(1)(e). 
Section II.C(1) explains the form of the CO2 and fuel 
consumption standards, the numerical levels for those standards, and 
the approach to phasing in the standards over time. The measurement 
procedure for determining compliance is discussed in Section II.C(2), 
and the EPA and NHTSA compliance programs are discussed in Section 
II.C(3). Section II.C(4) discusses implementation flexibility 
provisions. Section II.E discusses additional standards and provisions 
for N2O and CH4 emissions, for vehicle air 
conditioning leakage, and for ethanol-fueled and electric vehicles. HD 
pickup and van air conditioning efficiency is not being regulated, for 
reasons discussed in Section II.E.
(1) What are the levels and timing of HD pickup and van standards?
(a) Vehicle-Based Standards
    About 90 percent of Class 2b and 3 vehicles are pickup trucks, 
passenger vans, and work vans that are sold by the original equipment 
manufacturers as complete vehicles, ready for use on the road. In 
addition, most of these

[[Page 57161]]

complete HD pickups and vans are covered by CAA vehicle emissions 
standards for criteria pollutants today (i.e., they are chassis tested 
similar to light-duty), expressed in grams per mile. This distinguishes 
this category from other, larger heavy-duty vehicles that typically 
have only the engines covered by CAA engine emission standards, 
expressed in grams per brake horsepower-hour. As a result, Class 2b and 
3 complete vehicles share much more in common with light-duty trucks 
than with other heavy-duty vehicles.
    Three of these commonalities are especially significant: (1) Over 
95 percent of the HD pickups and vans sold in the United States are 
produced by Ford, General Motors, and Chrysler--three companies with 
large light-duty vehicle and light-duty truck sales in the United 
States, (2) these companies typically base their HD pickup and van 
designs on higher sales volume light-duty truck platforms and 
technologies, often incorporating new light-duty truck design features 
into HD pickups and vans at their next design cycle, and (3) at this 
time most complete HD pickups and vans are certified to vehicle-based 
rather than engine-based EPA standards. There is also the potential for 
substantial GHG and fuel consumption reductions from vehicle design 
improvements beyond engine changes (such as through optimizing 
aerodynamics, weight, tires, and accessories), and the manufacturer is 
generally responsible for both engine and vehicle design. All of these 
factors together suggest that it is appropriate and reasonable to set 
standards for the vehicle as a whole, rather than to establish separate 
engine and vehicle GHG and fuel consumption standards, as is being done 
for the other heavy-duty categories. This approach for complete 
vehicles is consistent with Recommendation 8-1 of the NAS Report, which 
encourages the regulation of ``the final stage vehicle manufacturers 
since they have the greatest control over the design of the vehicle and 
its major subsystems that affect fuel consumption.'' There was 
consensus in the public comments supporting this approach.
(b) Work-Based Attributes
    In setting heavy-duty vehicle standards it is important to take 
into account the great diversity of vehicle sizes, applications, and 
features. That diversity reflects the variety of functions performed by 
heavy-duty vehicles, and this in turn can affect the kind of technology 
that is available to control emissions and reduce fuel consumption, and 
its effectiveness. EPA has dealt with this diversity in the past by 
making weight-based distinctions where necessary, for example in 
setting HD vehicle standards that are different for vehicles above and 
below 10,000 lb GVWR, and in defining different standards and useful 
life requirements for light-, medium-, and heavy-heavy-duty engines. 
Where appropriate, distinctions based on fuel type have also been made, 
though with an overall goal of remaining fuel-neutral.
    The joint EPA GHG and NHTSA fuel economy rules for light-duty 
vehicles accounted for vehicle diversity in that segment by basing 
standards on vehicle footprint (the wheelbase times the average track 
width). Passenger cars and light trucks with larger footprints are 
assigned numerically higher target levels for GHGs and numerically 
lower target levels for fuel economy in acknowledgement of the 
differences in technology as footprint gets larger, such that vehicles 
with larger footprints have an inherent tendency to burn more fuel and 
emit more GHGs per mile of travel. Using a footprint-based attribute to 
assign targets also avoids interfering with the ability of the market 
to offer a variety of products to maintain consumer choice.
    In developing this rulemaking, the agencies emphasized creating a 
program structure that would achieve reductions in fuel consumption and 
GHGs based on how vehicles are used and on the work they perform in the 
real world, consistent with the NAS report recommendations to be 
mindful of HD vehicles' unique purposes. Despite the HD pickup and van 
similarities to light-duty vehicles, we believe that the past practice 
in EPA's heavy-duty program of using weight-based distinctions in 
dealing with the diversity of HD pickup and van products is more 
appropriate than using vehicle footprint. Work-based measures such as 
payload and towing capability are key among the things that 
characterize differences in the design of vehicles, as well as 
differences in how the vehicles will be used. Vehicles in this category 
have a wide range of payload and towing capacities. These work-based 
differences in design and in-use operation are the key factors in 
evaluating technological improvements for reducing CO2 
emissions and fuel consumption. Payload has a particularly important 
impact on the test results for HD pickup and van emissions and fuel 
consumption, because testing under existing EPA procedures for criteria 
pollutants is conducted with the vehicle loaded to half of its payload 
capacity (rather than to a flat 300 lb as in the light-duty program), 
and the correlation between test weight and fuel use is strong.\112\
---------------------------------------------------------------------------

    \112\ Section II.C(2) discusses our decision that GHGs and fuel 
consumption for HD pickups and vans be measured using the same test 
conditions as in the existing EPA program for criteria pollutants.
---------------------------------------------------------------------------

    Towing, on the other hand, does not directly factor into test 
weight as nothing is towed during the test. Hence only the higher curb 
weight caused by heavier truck components would play a role in 
affecting measured test results. However towing capacity can be a 
significant factor to consider because HD pickup truck towing 
capacities can be quite large, with a correspondingly large effect on 
design.
    We note too that, from a purchaser perspective, payload and towing 
capability typically play a greater role than physical dimensions in 
influencing purchaser decisions on which heavy-duty vehicle to buy. For 
passenger vans, seating capacity is of course a major consideration, 
but this correlates closely with payload weight.
    Although heavy-duty vehicles are traditionally classified by their 
GVWR, we do not believe that GVWR is the best weight-based attribute on 
which to base GHG and fuel consumption standards for this group of 
vehicles. GVWR is a function of not only payload capacity but of 
vehicle curb weight as well; in fact, it is the simple sum of the two. 
Allowing more GHG emissions from vehicles with higher curb weight tends 
to penalize lightweighted vehicles with comparable payload capabilities 
by making them meet more stringent standards than they would have had 
to meet without the weight reduction. The same would be true for 
another common weight-based measure, the gross vehicle combination 
weight, which adds the maximum combined towing and payload weight to 
the curb weight.
    Similar concerns about using weight-based attributes that include 
vehicle curb weight were raised in the EPA/NHTSA proposal for light-
duty GHG and fuel economy standards: ``footprint-based standards 
provide an incentive to use advanced lightweight materials and 
structures that would be discouraged by weight-based standards'', and 
``there is less risk of `gaming' (artificial manipulation of the 
attribute(s) to achieve a more favorable target) by increasing 
footprint under footprint-based standards than by increasing vehicle 
mass under weight-based standards--it is relatively easy for a 
manufacturer to add enough weight to a vehicle to decrease its 
applicable fuel economy target a significant amount, as compared to 
increasing vehicle footprint'' (74 FR 49685, September 28,

[[Page 57162]]

2009). The agencies believe that using payload and towing capacities as 
the work-based attributes avoids the above-mentioned disincentive for 
the use of lightweighting technology by taking vehicle curb weight out 
of the standards determination.
    After taking these considerations into account, EPA and NHTSA 
proposed to set standards for HD pickups and vans based on the proposed 
``work factor'' attribute that combines vehicle payload capacity and 
vehicle towing capacity, in pounds, with an additional fixed adjustment 
for four-wheel drive (4wd) vehicles. This adjustment accounts for the 
fact that 4wd, critical to enabling the many off-road heavy-duty work 
applications, adds roughly 500 lb to the vehicle weight. There was 
consensus in the public comments supporting this attribute, and the 
agencies are adopting it as proposed. Target GHG and fuel consumption 
standards will be determined for each vehicle with a unique work factor 
(analogous to a target for each discrete vehicle footprint in the 
light-duty vehicle rules). These targets will then be production 
weighted and summed to derive a manufacturer's annual fleet average 
standard for its heavy-duty pickups and vans. Widespread support for 
the proposed work factor-based approach to standards and fleet average 
approach to compliance was expressed in the comments we received.
    To ensure consistency and help preclude gaming, we are finalizing 
the proposed provision that payload capacity be defined as GVWR minus 
curb weight, and towing capacity as GCWR minus GVWR. For purposes of 
determining the work factor, GCWR is defined according to the Society 
of Automotive Engineers (SAE) Recommended Practice J2807 APR2008, GVWR 
is defined consistent with EPA's criteria pollutants program, and curb 
weight is defined as in 40 CFR 86.1803-01. Based on analysis of how 
CO2 emissions and fuel consumption correlate to work factor, 
we believe that a straight line correlation is appropriate across the 
spectrum of possible HD pickups and vans, and that vehicle distinctions 
such as Class 2b versus Class 3 need not be made in setting standards 
levels for these vehicles.\113\ This approach was supported by 
commenters.
---------------------------------------------------------------------------

    \113\ Memorandum from Anthony Neam and Jeff Cherry, U.S.EPA, to 
docket EPA-HQ-OAR-2010-0162, October 18, 2010.
---------------------------------------------------------------------------

    We note that payload/towing-dependent gram per mile and gallon per 
100 mile standards for HD pickups and vans parallel the gram per ton-
mile and gallon per 1,000 ton-mile standards being finalized for Class 
7 and 8 combination tractors and for vocational vehicles. Both 
approaches account for the fact that more work is done, more fuel is 
burned, and more CO2 is emitted in moving heavier loads than 
in moving lighter loads. Both of these load-based approaches avoid 
penalizing vehicle designers wishing to reduce GHG emissions and fuel 
consumption by reducing the weight of their trucks. However, the 
sizeable diversity in HD work truck and van applications, which go well 
beyond simply transporting freight, and the fact that the curb weights 
of these vehicles are on the order of their payload capacities, suggest 
that setting simple gram/ton-mile and gallon/ton-mile standards for 
them is not appropriate. Even so, we believe that our setting of 
payload-based standards for HD pickups and vans is consistent with the 
NAS Report's recommendation in favor of load-specific fuel consumption 
standards. Again, commenters agreed with this approach to setting HD 
pickup and van standards.
    These attribute-based CO2 and fuel consumption standards 
are meant to be relatively consistent from a stringency perspective. 
Vehicles across the entire range of the HD pickup and van segment have 
their respective target values for CO2 emissions and fuel 
consumption, and therefore all HD pickups and vans will be affected by 
the standard. With this attribute-based standards approach, EPA and 
NHTSA believe there should be no significant effect on the relative 
distribution of vehicles with differing capabilities in the fleet, 
which means that buyers should still be able to purchase the vehicle 
that meets their needs.
(c) Standards
    The agencies are finalizing standards based on a technology 
analysis performed by EPA to determine the appropriate HD pickup and 
van standards. This analysis, described in detail in RIA Chapter 2, 
considered:
     The level of technology that is incorporated in current 
new HD pickups and vans,
     The available data on corresponding CO2 
emissions and fuel consumption for these vehicles,
     Technologies that would reduce CO2 emissions 
and fuel consumption and that are judged to be feasible and appropriate 
for these vehicles through the 2018 model year,
     The effectiveness and cost of these technologies for HD 
pickup and vans,
     Projections of future U.S. sales for HD pickup and vans, 
and
     Forecasts of manufacturers' product redesign schedules.
    Based on this analysis, EPA is finalizing the proposed 
CO2 attribute-based target standards shown in Figure 0-2 and 
II-3, and NHTSA is finalizing the equivalent attribute-based fuel 
consumption target standards, also shown in Figure 0-2 and II-3, 
applicable in model year 2018. These figures also shows phase-in 
standards for model years before 2018, and their derivation is 
explained below, along with alternative implementation schedules to 
ensure equivalency between the EPA and NHTSA programs while meeting 
respective statutory obligations. Also, for reasons discussed below, 
the agencies proposed and are establishing separate targets for 
gasoline-fueled (and any other Otto-cycle) vehicles and diesel-fueled 
(and any other Diesel-cycle) vehicles. The targets will be used to 
determine the production-weighted fleet average standards that apply to 
the combined diesel and gasoline fleet of HD pickups and vans produced 
by a manufacturer in each model year.

[[Page 57163]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.002

    \114\ The NHTSA program provides voluntary standards for model 
years 2014 and 2015. Target line functions for 2016-2018 are for the 
second NHTSA alternative described in Section II.C(d)(ii).

---------------------------------------------------------------------------

[[Page 57164]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.003

    Described mathematically, EPA's and NHTSA's target standards are 
defined by the following formulae:
---------------------------------------------------------------------------

    \115\ The NHTSA program provides voluntary standards for model 
years 2014 and 2015. Target line functions for 2016-2018 are for the 
second NHTSA alternative described in Section II.C(d)(ii).

EPA CO2 Target (g/mile) = [a x WF] + b
NHTSA Fuel Consumption Target (gallons/100 miles) = [c x WF] + d

Where:

WF = Work Factor = [0.75 x (Payload Capacity + xwd)] + [0.25 x 
Towing Capacity]
Payload Capacity = GVWR (lb) - Curb Weight (lb)
xwd = 500 lb if the vehicle is equipped with 4wd, otherwise equals 0 
lb
Towing Capacity = GCWR (lb) - GVWR (lb)
Coefficients a, b, c, and d are taken from Table II-12 or Table II-
13.
---------------------------------------------------------------------------

    \116\ The NHTSA program provides voluntary standards for model 
years 2014 and 2015. Target line functions for 2016-2018 are for the 
second NHTSA alternative described in Section II.C(d)(ii).

 Table II-12--Coefficients for HD Pickup and Van Target Standards \116\
------------------------------------------------------------------------
           Model year                a        b          c          d
------------------------------------------------------------------------
                             Diesel Vehicles
------------------------------------------------------------------------
2014............................   0.0478      368     0.000470     3.61
2015............................   0.0474      366     0.000466     3.60
2016............................   0.0460      354     0.000452     3.48
2017............................   0.0445      343     0.000437     3.37
2018 and later..................   0.0416      320     0.000409     3.14
------------------------------------------------------------------------
                            Gasoline Vehicles
------------------------------------------------------------------------
2014............................   0.0482      371     0.000542     4.17
2015............................   0.0479      369     0.000539     4.15
2016............................   0.0469      362     0.000528     4.07
2017............................   0.0460      354     0.000518     3.98
2018 and later..................   0.0440      339     0.000495     3.81
------------------------------------------------------------------------

[[Page 57165]]

    Table II-13--Coefficients for NHTSA's First Alternative and EPA's
             Alternative HD Pickup and Van Target Standards
------------------------------------------------------------------------
           Model year                a        b          c          d
------------------------------------------------------------------------
                             Diesel Vehicles
------------------------------------------------------------------------
2014 a..........................   0.0478      368     0.000470     3.61
2015 a..........................   0.0474      366     0.000466     3.60
2016-2018.......................   0.0440      339     0.000432     3.33
2019 and later..................   0.0416      320     0.000409     3.14
------------------------------------------------------------------------
                            Gasoline Vehicles
------------------------------------------------------------------------
2014 a..........................   0.0482      371     0.000542     4.17
2015 a..........................   0.0479      369     0.000539     4.15
2016-2018.......................   0.0456      352     0.000513     3.96
2019 and later..................   0.0440      339     0.000495     3.81
------------------------------------------------------------------------
Notes:
a NHTSA standards will be voluntary in 2014 and 2015.

    These targets are based on a set of vehicle, engine, and 
transmission technologies assessed by the agencies and determined to be 
feasible and appropriate for HD pickups and vans in the 2014-2018 
timeframe. See Section III.B for a detailed analysis of these vehicle, 
engine and transmission technologies, including their feasibility, 
costs, and effectiveness in HD pickups and vans.
    To calculate a manufacturer's HD pickup and van fleet average 
standard, the agencies are requiring that separate target curves be 
used for gasoline and diesel vehicles. The agencies estimate that in 
2018 the target curves will achieve 15 and 10 percent reductions in 
CO2 and fuel consumption for diesel and gasoline vehicles, 
respectively, relative to a common baseline for current (model year 
2010) HD pickup trucks and vans. An additional two percent reduction in 
GHGs will be achieved by the direct air conditioning leakage standard 
in the EPA standards. These reductions are based on the agencies' 
assessment of the feasibility of incorporating technologies (which 
differ significantly for gasoline and diesel powertrains) in the 2014-
2018 model years, and on the differences in relative efficiency in the 
current gasoline and diesel vehicles. The resulting reductions 
represent roughly equivalent stringency levels for gasoline and diesel 
vehicles, which is important in ensuring our program maintains product 
choices available to vehicle buyers.
    In written comments on the proposal, Cummins objected to setting 
separate diesel and gasoline vehicle standards, on the basis that it 
increases the burden for diesel engine manufacturers more than for 
gasoline engine manufacturers, and thereby could shift market share 
away from diesels. EMA argued for fuel-neutrality based on historical 
precedent and the fact that GHGs emitted by one type of engine are no 
different than those emitted by another type of engine. We believe that 
both engine types have roughly equivalent redesign burdens as evidenced 
by the feasibility and cost analysis in RIA Chapter 2. Also, even 
though the emissions and fuel consumption reductions are expressed from 
a common diesel/gasoline baseline in these final rules, the actual 
starting base for diesels is at a lower level than for gasoline 
vehicles. Other industry commenters, including those with sizeable 
diesel sales, expressed general support for the standards. The agencies 
agree that standards that do not distinguish between fuel types are 
generally preferable where technological or market-based reasons do not 
strongly argue otherwise. These technological differences exist 
presently between gasoline and diesel engines for GHGs, as described 
above. The agencies emphasize, however, that they are not committed to 
perpetuating separate GHG standards for gasoline and diesel heavy-duty 
vehicles and engines, and expect to reexamine the need for separate 
gasoline/diesel standards in the next rulemaking.
    Environmental groups and others commented that the proposed 
standards were not stringent enough, citing the heavy-duty vehicle NAS 
study finding that technologies such as hybridization are feasible. 
However, in the ambitious timeframe we are focusing on for these rules, 
targeting as it does technologies implementable in the HD pickup and 
van fleet starting in 2014 and phasing in with normal product redesign 
cycles through 2018, our assessment shows that the standards we are 
establishing are appropriate. More advanced technologies considered in 
the NAS report would be appropriate for consideration in future 
rulemaking activity. Additional conventional technologies identified by 
commenters as promising in light-duty applications and potentially 
useful for HD applications are discussed in RIA chapter 2.
    The NHTSA fuel consumption target curves and the EPA GHG target 
curves are equivalent. The agencies established the target curves using 
the direct relationship between fuel consumption and CO2 
using conversion factors of 8,887 g CO2/gallon for gasoline 
and 10,180 g CO2/gallon for diesel fuel.
    It is expected that measured performance values for CO2 
will generally be equivalent to fuel consumption. However, as explained 
below in Section 0, EPA is finalizing a provision for manufacturers to 
use CO2 credits to help demonstrate compliance with 
N2O and CH4 emissions standards, by expressing 
any N2O and CH4 undercompliance in terms of their 
CO2-equivalent and applying the needed CO2 
credits. For test families that do not use this compliance alternative, 
the measured performance values for CO2 and fuel consumption 
will be equivalent because the same test runs and measurement data will 
be used to determine both values, and calculated fuel consumption will 
be based on the same conversion factors that are used to establish the 
relationship between the CO2 and fuel consumption target 
curves (8,887 g CO2/gallon for gasoline and 10,180 g 
CO2/gallon for diesel fuel). For manufacturers that choose 
to use the EPA provision for CO2 credit use in demonstrating 
N2O and CH4 compliance, compliance with the 
CO2 standard will not be directly equivalent to compliance 
with the NHTSA fuel consumption standard.

[[Page 57166]]

(d) Implementation Plan
(i) EPA Program Phase-In MY 2014-2018
    EPA is finalizing the proposed provision that the GHG standards be 
phased in gradually over the 2014-2018 model years, with full 
implementation effective in the 2018 model year. Therefore, 100 percent 
of a manufacturer's vehicle fleet will need to meet a fleet-average 
standard that will become increasingly more stringent each year of the 
phase-in period. For both gasoline and diesel vehicles, this phase-in 
will be 15-20-40-60-100 percent of the model year 2018 stringency in 
model years 2014-2015-2016-2017-2018, respectively. These percentages 
reflect stringency increases from a baseline performance level for 
model year 2010, determined by the agencies based on EPA and 
manufacturer data. Because these vehicles are not currently regulated 
for GHG emissions, this phase-in takes the form of target line 
functions for gasoline and diesel vehicles that become increasingly 
stringent over the phase-in model years. These year-by-year functions 
have been derived in the same way as the 2018 function, by taking a 
percent reduction in CO2 from a common unregulated baseline. 
For example, in 2014 the reduction for both diesel and gasoline 
vehicles will be 15 percent of the fully-phased-in reductions. Figures 
II-2 and II-3, and Table 0-12, reflect this phase-in approach.
    EPA is also providing manufacturers with an optional alternative 
implementation schedule in model years 2016 through 2018, equivalent to 
NHTSA's first alternative for standards that do not change over these 
model years, described below. Under this option the phase-in will be 
15-20-67-67-67-100 percent of the model year 2019 stringency in model 
years 2014-2015-2016-2017-2018-2019, respectively. Table 0-13, above, 
provides the coefficients ``a'' and ``b'' for this manufacturer's 
alternative. As explained below, this alternative will provide roughly 
equivalent overall CO2 reductions and fuel consumption 
improvements as the 15-20-40-60-100 percent phase-in. In addition, as 
explained below, the stringency of this alternative was established by 
NHTSA such that a manufacturer with a stable production volume and mix 
over the model year 2016-2018 period could use Averaging, Banking and 
Trading to comply with either alternative and have a similar credit 
balance at the end of model year 2018.
    Under the above-described alternatives, each manufacturer will need 
to demonstrate compliance with the applicable fleet average standard 
using that year's target function over all of its HD pickups and vans 
starting with its MY 2014 fleet of HD pickups and vans. No comments 
were received in support of an alternative approach that EPA requested 
comment on, involving phasing in an annually increasing percentage of 
each manufacturer's sales volume.
(ii) NHTSA Program Phase-In 2016 and Later
    NHTSA is finalizing the proposed provision to allow manufacturers 
to select one of two fuel consumption standard alternatives for model 
years 2016 and later. Each manufacturer will select an alternative in 
its joint pre-model year report, discussed below, that is now required 
to be electronically submitted to the agencies; and, once selected, the 
alternative will apply for model years 2016 and later, and cannot be 
reversed. The first alternative will define a fuel consumption target 
line function for gasoline vehicles and a target line function for 
diesel vehicles that will not change for model years 2016 to 2018. The 
target line function coefficients are provided in Table II-13.
    The second alternative will be equivalent to the EPA target line 
functions in each model year starting in 2016 and continuing 
afterwards. Stringency of fuel consumption standards will increase 
gradually for the 2016 and later model years. Relative to a model year 
2010 unregulated baseline for both gasoline and diesel vehicles, 
stringency will be 40, 60, and 100 percent of the 2018 target line 
function in model years 2016, 2017, and 2018, respectively. The 
stringency of the target line functions in the first alternative for 
model years 2016-2017-2018-2019 is 67-67-67-100 percent, respectively, 
of the 2019 stringency in the second alternative. The stringency of the 
first alternative was established so that a manufacturer with a stable 
production volume and mix over the model year 2016-2018 period could 
use Averaging, Banking and Trading to comply with either alternative 
and have a similar credit balance at the end of model year 2018 under 
the EPA and NHTSA programs.
(iii) NHTSA Voluntary Standards Period
    NHTSA is finalizing the proposed provision that manufacturers may 
voluntarily opt into the NHTSA HD pickup and van program in model years 
2014 or 2015. If a manufacturer elects to opt in to the program, it 
must stay in the program for all the optional model years. 
Manufacturers that opt in become subject to NHTSA standards for all 
regulatory categories. To opt into the program, a manufacturer must 
declare its intent to opt in to the program in its Pre-Model Year 
Report. The agencies have finalized new requirements for manufacturers 
to provide all early model declarations as a part of the pre-model year 
reports. See regulatory text for 49 CFR 535.8 for information related 
to the Pre-Model Year Report. A manufacturer would begin tracking 
credits and debits beginning in the model year in which they opt into 
the program. The handling of credits and debits would be the same as 
for the mandatory program.
    For manufacturers that opt into NHTSA's HD pickup and van fuel 
consumption program in 2014 or 2015, the stringency would increase 
gradually each model year. Relative to a model year 2010 unregulated 
baseline, for both gasoline and diesel vehicles, stringency would be 
15-20 percent of the model year 2019 target line function stringency 
(under the NHTSA first alternative) and 15-20 percent of the model year 
2018 target line function stringency (under the NHTSA second 
alternative) in model years 2014-2015, respectively. The corresponding 
absolute standards target levels are provided in Figure II-2 and II-3, 
and the accompanying equations.
(2) What are the HD pickup and van test cycles and procedures?
    EPA and NHTSA are finalizing the proposed provision that HD pickup 
and van testing be conducted using the same heavy-duty chassis test 
procedures currently used by EPA for measuring criteria pollutant 
emissions from these vehicles, but with the addition of the highway 
fuel economy test cycle (HFET) currently required only for light-duty 
vehicle GHG emissions and fuel economy testing. Although the highway 
cycle driving pattern is identical to that of the light-duty test, 
other test parameters for running the HFET, such as test vehicle loaded 
weight, are identical to those used in running the current EPA Federal 
Test Procedure for complete heavy-duty vehicles.
    The GHG and fuel consumption results from vehicle testing on the 
Light-duty FTP and the HFET will be weighted by 55 percent and 45 
percent, respectively, and then averaged in calculating a combined 
cycle result. This result corresponds with the data used to develop the 
work factor-based CO2 and fuel consumption standards, since 
the data on the baseline and technology efficiency was also

[[Page 57167]]

developed in the context of these test procedures. The addition of the 
HFET and the 55/45 cycle weightings are the same as for the light-duty 
CO2 and CAFE programs, as we believe the real world driving 
patterns for HD pickups and vans are not too unlike those of light-duty 
trucks, and we are not aware of data specifically on these patterns 
that would lead to a different choice of cycles and weightings, nor did 
any commenters provide such data. More importantly, we believe that the 
55/45 weightings will provide for effective reductions of GHG emissions 
and fuel consumption from these vehicles, and that other weightings, 
even if they were to more precisely match real world patterns, are not 
likely to significantly improve the program results.
    Another important parameter in ensuring a robust test program is 
vehicle test weight. Current EPA testing for HD pickup and van criteria 
pollutants is conducted with the vehicle loaded to its Adjusted Loaded 
Vehicle Weight (ALVW), that is, its curb weight plus [frac12] of the 
payload capacity. This is substantially more challenging than loading 
to the light-duty vehicle test condition of curb weight plus 300 
pounds, but we believe that this loading for HD pickups and vans to 
[frac12] payload better fits their usage in the real world and will 
help ensure that technologies meeting the standards do in fact provide 
real world reductions. The choice is likewise consistent with use of an 
attribute based in considerable part on payload for the standard. We 
see no reason to set test load conditions differently for GHGs and fuel 
consumption than for criteria pollutants, and we are not aware of any 
new information (such as real world load patterns) since the ALVW was 
originally set this way that would support a change in test loading 
conditions, nor did any commenters provide such information. We are 
therefore using ALVW for test vehicle loading in GHG and fuel 
consumption testing.
    Additional provisions for our final testing and compliance program 
are provided in Section V.B.
(3) How are the HD pickup and van standards structured?
    EPA and NHTSA are finalizing the proposed fleet average standards 
for new HD pickups and vans, based on a manufacturer's new vehicle 
fleet makeup. In addition, EPA is finalizing proposed in-use standards 
that apply to the individual vehicles in this fleet over their useful 
lives. The compliance provisions for these fleet average and in-use 
standards for HD pickups and vans are largely based on the recently 
promulgated light-duty GHG and fuel economy program, as described in 
detail in the proposal.
(a) Fleet Average Standards
    In the programs we are finalizing, each manufacturer will have a 
GHG standard and a fuel consumption standard unique to its new HD 
pickup and van fleet in each model year, depending on the load 
capacities of the vehicle models produced by that manufacturer, and on 
the U.S.-directed production volume of each of those models in that 
model year. Vehicle models with larger payload/towing capacities have 
individual targets at numerically higher CO2 and fuel 
consumption levels than lower payload/towing vehicles, as discussed in 
Section II.C(1). The fleet average standard for a manufacturer is a 
production-weighted average of the work factor-based targets assigned 
to unique vehicle configurations within each model type produced by the 
manufacturer in a model year.
    The fleet average standard with which the manufacturer must comply 
is based on its final production figures for the model year, and thus a 
final assessment of compliance will occur after production for the 
model year ends. Because compliance with the fleet average standards 
depends on actual test group production volumes, it is not possible to 
determine compliance at the time the manufacturer applies for and 
receives an EPA certificate of conformity for a test group. Instead, at 
certification the manufacturer will demonstrate a level of performance 
for vehicles in the test group, and make a good faith demonstration 
that its fleet, regrouped by unique vehicle configurations within each 
model type, is expected to comply with its fleet average standard when 
the model year is over. EPA will issue a certificate for the vehicles 
covered by the test group based on this demonstration, and will include 
a condition in the certificate that if the manufacturer does not comply 
with the fleet average, then production vehicles from that test group 
will be treated as not covered by the certificate to the extent needed 
to bring the manufacturer's fleet average into compliance. As in the 
light-duty program, additional ``model type'' testing will be conducted 
by the manufacturer over the course of the model year to supplement the 
initial test group data. The emissions and fuel consumption levels of 
the test vehicles will be used to calculate the production-weighted 
fleet averages for the manufacturer, after application of the 
appropriate deterioration factor to each result to obtain a full useful 
life value. See generally 75 FR 25470-25472.
    EPA and NHTSA do not currently anticipate notable deterioration of 
CO2 emissions and fuel consumption performance, and are 
therefore requiring that an assigned deterioration factor be applied at 
the time of certification: an additive assigned deterioration factor of 
zero, or a multiplicative factor of one will be used. EPA and NHTSA 
anticipate that the deterioration factor may be updated from time to 
time, as new data regarding emissions deterioration for CO2 
are obtained and analyzed. Additionally, EPA and NHTSA may consider 
technology-specific deterioration factors, should data indicate that 
certain control technologies deteriorate differently than others. See 
also 75 FR 25474.
(b) In-Use Standards
    Section 202(a)(1) of the CAA specifies that EPA set emissions 
standards that are applicable for the useful life of the vehicle. The 
in-use standards that EPA is finalizing apply to individual vehicles. 
NHTSA is not adopting in-use standards because they are not required 
under EISA, and because it is not currently anticipated that there will 
be any notable deterioration of fuel consumption. For the EPA program, 
compliance with the in-use standard for individual vehicles and vehicle 
models will not impact compliance with the fleet average standard, 
which will be based on the production-weighted average of the new 
vehicles.
    EPA is finalizing the proposed provision that the in-use standards 
for HD pickups and vans be established by adding an adjustment factor 
to the full useful life emissions and fuel consumption results used to 
calculate the fleet average. EPA is also finalizing the proposed 
provision that the useful life for these vehicles with respect to GHG 
emissions be set equal to their useful life for criteria pollutants: 11 
years or 120,000 miles, whichever occurs first (40 CFR 86.1805-04(a)).
    As discussed above, we are finalizing the proposed provision that 
certification test results obtained before and during the model year be 
used directly to calculate the fleet average emissions for assessing 
compliance with the fleet average standard. Therefore, this assessment 
and the fleet average standard itself do not take into account test-to-
test variability and production variability that can affect measured 
in-use levels. For this reason, EPA is finalizing the proposed 
adjustment factor for the in-use standard to provide some margin for 
production and test-to-

[[Page 57168]]

test variability that could result in differences between the initial 
emission test results used to calculate the fleet average and emission 
results obtained during subsequent in-use testing. EPA is finalizing 
the proposed provision that each model's in-use CO2 standard 
be the model-specific level used in calculating the fleet average, plus 
10 percent. This is the same as the approach taken for light-duty 
vehicle GHG in-use standards (See 75 FR 25473-25474). No adverse 
comments were received on this proposed provision.
    As it does now for heavy-duty vehicle criteria pollutants, EPA will 
use a variety of mechanisms to conduct assessments of compliance with 
the in-use standards, including pre-production certification and in-use 
monitoring once vehicles enter customer service. The full useful life 
in-use standards apply to vehicles that have entered customer service. 
The same standards apply to vehicles used in pre-production and 
production line testing, except that deterioration factors are not 
applied.
(4) What HD pickup and van flexibility provisions are being 
established?
    This program contains substantial flexibility in how manufacturers 
can choose to implement the EPA and NHTSA standards while preserving 
their timely benefits for the environment and energy security. Primary 
among these flexibilities are the gradual phase-in schedule, 
alternative compliance paths, and corporate fleet average approach 
which encompasses averaging, banking and trading described above. 
Additional flexibility provisions are described briefly here and in 
more detail in Section IV.
    As explained in Section II.C(3), we are finalizing the proposed 
provision that, at the end of each model year, when production for the 
model year is complete, a manufacturer calculate its production-
weighted fleet average CO2 and fuel consumption. Under this 
approach, a manufacturer's HD pickup and van fleet that achieves a 
fleet average CO2 or fuel consumption level better than its 
standard will be allowed to generate credits. Conversely, if the fleet 
average CO2 or fuel consumption level does not meet its 
standard, the fleet would incur debits (also referred to as a 
shortfall).
    A manufacturer whose fleet generates credits in a given model year 
will have several options for using those credits to offset emissions 
from other HD pickups and vans. These options include credit carry-
back, credit carry-forward, and credit trading. These provisions exist 
in the light-duty 2012-2016 MY vehicle rule, and similar provisions are 
part of EPA's Tier 2 program for light-duty vehicle criteria pollutant 
emissions, as well as many other mobile source standards issued by EPA 
under the CAA. The manufacturer will be able to carry back credits to 
offset a deficit that had accrued in a prior model year and was 
subsequently carried over to the current model year, with a limitation 
on the carry-back of credits to three model years, consistent with the 
light-duty program. We are finalizing the proposed provision that, 
after satisfying any need to offset pre-existing deficits, a 
manufacturer may bank remaining credits for use in future years, with a 
limitation on the carry-forward of credits to five model years. We are 
also finalizing the proposed provision that manufacturers may certify 
their HD pickup and van fleet a year early, in MY 2013, to generate 
credits against the MY 2014 standards. This averaging, banking, and 
trading program for HD pickups and vans is discussed in more detail in 
Section IV.A. For reasons discussed in detail in that section, we are 
not finalizing any credit transferability to or from other credit 
programs or averaging sets.
    Consistent with the President's May 21, 2010, directive to promote 
advanced technology vehicles and with the agencies' respective 
statutory authorities, we are adopting flexibility provisions that 
parallel similar provisions adopted in the light-duty program. These 
include credits for advance technology vehicles such as electric 
vehicles, and credits for innovative technologies that are shown by the 
manufacturer to provide GHG and fuel consumption reductions in real 
world driving, but not on the test cycle. See Section IV.B.

D. Class 2b-8 Vocational Vehicles

    Heavy-duty vehicles serve a vast range of functions including 
service for urban delivery, refuse hauling, utility service, dump, 
concrete mixing, transit service, shuttle service, school bus, 
emergency, motor homes,\117\ and tow trucks to name only a small subset 
of the full range of vehicles. The vehicles designed to serve these 
functions are as unique as the jobs they do. They are vastly 
different--one from the other--in size, shape and function. The 
agencies were unable to develop a specific vehicle definition based on 
the characteristics of these vehicles. Instead at proposal, we proposed 
to define that Class 2b-8 vocational vehicles as all heavy-duty 
vehicles which are not included in the Heavy-duty Pickup Truck and Van 
or the Class 7 and 8 Tractor categories. In effect, we said everything 
that is not a combination tractor or a pickup truck or van is a 
vocational vehicle. We are finalizing that definition as proposed 
reflecting the same challenges we faced at proposal regarding defining 
the full range of heavy-duty vehicles. As at proposal, recreational 
vehicles are included under EPA's standards but are not included under 
NHTSA's final standards. The agencies note that we are adding 
vocational tractors to the vocational vehicle category in the final 
rulemaking, as described above in Section II.B.
---------------------------------------------------------------------------

    \117\ See above for discussion of applicability of NHTSA's 
standards to non-commercial vehicles.
---------------------------------------------------------------------------

    The agencies proposed that Class 4 pickup trucks although similar 
to Class 2b and 3 vehicles be included in the vocational vehicle 
category. Comments from EMA, Cummins, NTEA and Navistar supported the 
premise that Class 4 vehicles belong as part of the vocational vehicle 
program because they are specifically designed and engineered to meet 
vocational requirements. They stated that components such as 
transmissions, axles, frames, and tires differ from the similar pickup 
trucks and vans in the Class 2b and 3 market. We agree with commenters' 
arguments that there are a number of important differences between the 
Class 4 and Class 3 trucks it unreasonable to regulate Class 4 vehicles 
under the standards for heavy duty pickups and vans. As a result, we 
are keeping Class 4 vehicles in the vocational vehicle category, but 
are allowing the optional chassis certification of Class 4 and 5 
vehicles. (See Section V.B(1)(e)).
    As mentioned in Section I, vocational vehicles undergo a complex 
build process. Often an incomplete chassis is built by a chassis 
manufacturer with an engine purchased from an engine manufacturer and a 
transmission purchased from another manufacturer. A body manufacturer 
purchases an incomplete chassis which is then completed by attaching 
the appropriate features to the chassis.
    The diversity in the vocational vehicle segment can be primarily 
attributed to the variety of vehicle bodies rather than to the chassis. 
For example, a body builder can build either a Class 6 bucket truck or 
a Class 6 delivery truck from the same Class 6 chassis. The aerodynamic 
difference between these two vehicles due to their bodies will lead to 
different baseline fuel consumption and GHG emissions. However, the 
baseline fuel consumption and emissions due to the components included 
in the common chassis (such as the engine, drivetrain, frame, and

[[Page 57169]]

tires) will be the same between these two types of complete vehicles.
    The agencies face difficulties in establishing the baseline 
CO2 and fuel consumption performance for the wide variety of 
complete vocational vehicles because of the very large number of 
vehicle types and the need to conduct testing on each of the vehicle 
types to establish the baseline. To establish standards for a complete 
vocational vehicle, it would be necessary to assess the potential for 
fuel consumption and GHG emissions improvement for each of these 
vehicle types and to establish standards for each vehicle type. Because 
of the size and complexity of this task, the agencies judged it was not 
practical to regulate complete vocational vehicles for this first fuel 
consumption and GHG emissions program. To overcome the lack of baseline 
information from the different vehicle types and to still achieve 
improvements to fuel consumption and GHG emissions, the agencies 
proposed to set standards for the chassis manufacturers of vocational 
vehicles (but not the body builders) and the engine manufacturers. 
Chassis manufacturers represent a limited number of companies as 
compared to body builders, which are made up of a diverse set of 
companies that are typically small businesses. These companies would 
need to be regulated if whole vehicle standards were established.
    Similar to combination tractors, the agencies proposed to set 
separate vehicle and engine standards for vocational vehicles. A number 
of comments were received on the proposal to regulate chassis and 
engine manufacturers. The agencies received comments from DTNA 
supporting the proposal to regulate the chassis manufacturer but not 
body manufacturers. While organizations like Cummins and ICCT expressed 
support for separate engine and vehicle standards, Navistar, Pew, and 
Volvo, in contrast, opposed separate engine and chassis standards, 
stating that separate engine standards disadvantages integrated truck/
engine manufacturers and full vehicle standards should be required. 
Volvo asked that the standards include an alternative integrated 
standard as well as complete vehicle modeling and testing beginning in 
2017. ACEEE and Sierra Club stated that the proposed standards and test 
procedures should move the agencies closer to full vehicle testing.
    Although the agencies understand that full vehicle standards would 
allow integrated truck/engine manufacturers--such as electrified 
accessories and weight reduction--the agencies are finalizing separate 
standards for vocational vehicles that apply to chassis manufacturers 
and engine standards for engines installed in these vehicles that apply 
to engine manufacturers. The agencies continue to believe that it is 
not practical to regulate complete vocational vehicles for this first 
fuel consumption and GHG emissions program because of the size and 
complexity of the task associated with assessing the potential for fuel 
consumption and GHG emissions improvement for each of the myriad types 
of vocational vehicles. This issue is discussed further in comment 
responses found in sections 5 and 6.1.4 of the Response to Comment 
Document, as well as in the following section of the preamble. Thus, 
the agencies are finalizing a set of standards for the chassis 
manufacturers of vocational vehicles (but not the body builders) and 
for the manufacturers of HD engines used in vocational vehicles.
(1) What are the vocational vehicle and engine CO2 and fuel 
consumption standards and their timing?
    In the NPRM, the agencies proposed vehicle standards based on the 
agencies' assessment of the availability of low rolling resistance 
tires that could be applied generally to vocational vehicles across the 
entire category. The agencies considered the possibility of including 
other technologies in determining the proposed stringency of the 
vocational vehicle standards, such as aerodynamic improvements, but as 
discussed in the NPRM, tentatively concluded that such improvements 
would not be appropriate for basing vehicle standard stringency in this 
phase of the rulemaking.\118\ For example, the aerodynamics of a 
recovery vehicle are impacted significantly by the equipment such as 
the arm located on the exterior of the truck.\119\ The agencies found 
little opportunity to improve the aerodynamics of the equipment on the 
truck. The agencies also evaluated the aerodynamic opportunities 
discussed in the NAS report. The panel found that there was minimal 
fuel consumption reduction opportunity through aerodynamic technologies 
for bucket trucks, transit buses, and refuse trucks \120\ primarily due 
to the low vehicle speed in normal operation. The panel did report that 
there are opportunities to reduce the fuel consumption of straight 
trucks by approximately 1 percent for trucks which operate at the 
average speed typical of a pickup and delivery truck (30 mph), although 
the opportunity is greater for vehicles that operate at higher 
speeds.\121\
---------------------------------------------------------------------------

    \118\ See 75 FR at 74241.
    \119\ A recovery vehicle removes or recovers vehicles that are 
disabled (broken down).
    \120\ See 2010 NAS Report, Note 21, page 133.
    \121\ See 2010 NAS Report, Note 21, page 110.
---------------------------------------------------------------------------

    The agencies received comments from the Motor Equipment 
Manufacturers Association, Eaton, NRDC, NESCAUM, NACAA, ACEEE, ICCT, 
Navistar, Arvin Meritor, the Union of Concerned Scientists and others 
that technologies such as idle reduction, advanced transmissions, 
advanced drivetrains, weight reduction, hybrid powertrains, and 
improved auxiliaries provide opportunities to reduce fuel consumption 
from vocational vehicles. Commenters asked that the agencies establish 
regulations that would reflect performance of these technologies and 
essentially force their utilization.
    The agencies assessed these technologies and have concluded that 
they may have the potential to reduce fuel consumption and GHG 
emissions from at least certain vocational vehicles, but the agencies 
have not been able to estimate baseline fuel consumption and GHG 
emissions levels for each type of vocational vehicle and for each type 
of technology, given the wide variety of models and uses of vocational 
vehicles. For example, idle reduction technologies such as APUs and 
cabin heaters can reduce workday idling associated with vocational 
vehicles. However, characterizing idling activity for the vocational 
segment in order to quantify the benefits of idle reduction technology 
is complicated by the variety of duty cycles found in the sector. 
Idling in school buses, fire trucks, pickup trucks, delivery trucks, 
and other types of vocational vehicles varies significantly. Given the 
great variety of duty cycles and operating conditions of vocational 
vehicles and the timing of these rules, it is not feasible at this time 
to establish an accurate baseline for quantifying the expected 
improvements which could result from use of idle reduction 
technologies. Similarly, for advanced drivetrains and advanced 
transmissions determining a baseline configuration, or a set of 
baseline configurations, is extremely difficult given the variety of 
trucks in this segment. The agencies do not believe that we can 
legitimately base standard stringency on the use of technologies for 
which we cannot identify baseline configurations, because absent 
baseline emissions and baseline fuel consumption, the emissions 
reductions achieved from introduction of the technology cannot be 
quantified. For some technologies, such as weight

[[Page 57170]]

reduction and improved auxiliaries--such as electrically driven power 
steering pumps and the vehicle's air conditioning system--the need to 
limit technologies to those under the control of the chassis 
manufacturer further restricted the agencies' options for predicating 
standard stringency on use of these technologies. For example, 
lightweight components that are under the control of chassis 
manufacturers are limited to a very few components such as frame rails. 
Considering the fuel efficiency and GHG emissions reduction benefits 
that will be achieved by finalizing these rules in the time frame 
proposed, rather than delaying in order to gain enough information to 
include additional technologies, the agencies have decided to finalize 
standards that do not assume the use of these technologies and will 
consider incorporating them in a later action applicable to later model 
years. Cf. Sierra Club v. EPA, 325 F. 3d 374, 380 (DC Cir. 2003) (in 
implementing a technology-forcing provision of the CAA, EPA reasonably 
adopted modest initial controls on an industry sector in order to 
better assess rules' effects in preparation for follow-up rulemaking).
    As the program progresses and the agencies gather more information, 
we expect to reconsider whether vocational vehicle standards for MYs 
2019 and beyond should be based on the use of additional technologies 
besides low rolling resistance tires.
    EPA is adopting CO2 standards and NHTSA is finalizing 
fuel consumption standards for manufacturers of chassis for new 
vocational vehicles and for manufacturers of heavy-duty engines 
installed in these vehicles. The final heavy-duty engine standards for 
CO2 emissions and fuel consumption focus on potential 
technological improvements in fuel combustion and overall engine 
efficiency and those controls would achieve most of the emission 
reductions. Further reductions from the Class 2b-8 vocational vehicle 
itself are possible within the time frame of these final regulations. 
Therefore, the agencies are also finalizing separate standards for 
vocational vehicles that will focus on additional reductions that can 
be achieved through improvements in vehicle tires. The agencies' 
analyses, as discussed briefly below and in more detail later in this 
preamble and in the RIA Chapter 2, show that these final standards 
appear appropriate under each agency's respective statutory 
authorities. Together these standards are estimated to achieve 
reductions of up to 10 percent from most vocational vehicles.
    EPA is also adopting standards to control N2O and 
CH4 emissions from Class 2b-8 vocational vehicles through 
controlling these GHG emissions from the HD engines. The final heavy-
duty engine standards for both N2O and CH4 and 
details of the standard are included in the discussion in Section 
II.E.1.b and II.E.2.b. EPA neither proposed nor is adopting air 
conditioning leakage standards applying to vocational vehicle chassis 
manufacturers.
    As discussed further below, the agencies are setting CO2 
and fuel consumption standards for the chassis based on tire rolling 
resistance improvements and for the engines based on engine 
technologies. The fuel consumption and GHG emissions impact of tire 
rolling resistance is impacted by the mass of the vehicle. However, the 
impact of mass on rolling resistance is relatively small so the 
agencies proposed to aggregate several vehicle weight categories under 
a single category for setting the standards. The agencies proposed to 
divide the vocational vehicle segment into three broad regulatory 
subcategories--Light Heavy-Duty (Class 2b through 5), Medium Heavy-Duty 
(Class 6 and 7), and Heavy Heavy-Duty (Class 8) which is consistent 
with the nomenclature used in the diesel engine classification. The 
agencies received comments supporting the division of vocational 
vehicles into three regulatory categories from DTNA. The agencies also 
received comments from Bosch, Clean Air Task Force, and National Solid 
Waste Management Association supporting a finer resolution of 
vocational vehicle subcategories. Their concerns include that the 
agencies' vehicle configuration in GEM is not representative of a 
particular vocational application, such as refuse trucks. Another 
recommendation was to divide the category by both GVWR and by 
operational characteristics. Upon further consideration, the agencies 
are finalizing as proposed three vocational vehicle subcategories 
because we believe this adequately balances simplicity while still 
obtaining reductions in this diverse segment. (As noted in section IV.A 
below, these three subcategories also denominate separate averaging 
sets for purposes of ABT.) Finer distinctions in regulatory 
subcategories would not change the technology basis for the standards 
or the reductions expected from the vocational vehicle category. As the 
agencies move towards future heavy-duty fuel consumption and GHG 
regulations for post-2017 model years, we intend to gather GHG and fuel 
consumption data for specific vocational applications which could be 
used to establish application-specific standards in the future.
    The agencies received comments supporting the exclusion of 
recreational vehicles, emergency vehicles, school buses from the 
vocational vehicle standards. The commenters argued that these 
individual vehicle types were small contributors to overall GHG 
emissions and that tires meeting their particular performance needs 
might not be available by 2014. The agencies considered these comments 
and the agencies have met with a number of tire manufacturers to better 
understand their expectations for product availability for the 2014 
model year. Based on our review of the information shared, we are 
convinced that tires with rolling resistance consistent with our final 
vehicle standards and meeting the full range of other performance 
characteristics desired in the vehicle market, including for RVs, 
emergency vehicles, and school buses, will be broadly available by the 
2014 model year.\122\ Absent regulations for the vast majority of 
vehicles in this segment, feasible cost-effective reductions available 
at reasonable cost in the 2014-2018 model years will be needlessly 
foregone. Therefore, the agencies have decided to finalize the 
vocational vehicle standards as proposed with recreational vehicles, 
emergency vehicles and school buses included in the vocational vehicle 
category. As RVs were not included by NHTSA for proposed regulation, 
they are not within the scope of the NPRM and are therefore excluded in 
NHTSA's portion of the final program. NHTSA will revisit this issue in 
the next rulemaking. In developing the final standards, the agencies 
have evaluated the current levels of emissions and fuel consumption, 
the kinds of technologies that could be utilized by manufacturers to 
reduce emissions and fuel consumption and the associated lead time, the 
associated costs for the industry, fuel savings for the consumer, and 
the magnitude of the CO2 and fuel savings that may be 
achieved. After examining the possibility of vehicle improvements based 
on use of the technologies underlying the standards for Class 7 and 8 
tractors, including improved aerodynamics, vehicle speed limiters, idle 
reduction technologies, tire rolling resistance, and weight reduction, 
as well as use of hybrid technologies, the agencies ultimately

[[Page 57171]]

determined to base the final vehicle standards on performance of tires 
with superior rolling resistance. For standards for diesel engines 
installed in vocational vehicles, the agencies examined performance of 
engine friction reduction, aftertreatment optimization, air handling 
improvements, combustion optimization, turbocompounding, and waste heat 
recovery, ultimately deciding to base the final standards on the 
performance of all of the technologies except turbocompounding and 
waste heat recovery systems. The standards for gasoline engine 
installed in vocational vehicles are based on performance of 
technologies such as gasoline direct injection, friction reduction, and 
variable valve timing. The agencies' evaluation indicates that these 
technologies, as described in Section III.C, are available today in the 
heavy-duty tractor and light-duty vehicle markets, but have very low 
application rates in the vocational vehicle market. The agencies have 
analyzed the technical feasibility of achieving the CO2 and 
fuel consumption standards, based on projections of what actions 
manufacturers would be expected to take to reduce emissions and fuel 
consumption to achieve the standards, and believe that the standards 
are cost-effective and technologically feasible and appropriate within 
the rulemaking time frame. EPA and NHTSA also present the estimated 
costs and benefits of the vocational vehicle standards in Section III.
---------------------------------------------------------------------------

    \122\ Bachman, Joseph. Memorandum to the Docket. Heavy-Duty Tire 
Evaluation. See Docket EPA-HQ-OAR-2010-0162. Pages 2-3 and 
Appendix B.
---------------------------------------------------------------------------

(a) Vocational Vehicle Chassis Standards
    In the NPRM, the agencies defined tire rolling resistance as a 
frictional loss of energy, associated mainly with the energy dissipated 
in the deformation of tires under load that influences fuel efficiency 
and CO2 emissions. Tires with higher rolling resistance lose 
more energy in response to this deformation, thus using more fuel and 
producing more CO2 emissions in operation, while tires with 
lower rolling resistance lose less energy, and save more fuel and 
CO2 emissions in operation. Tire design characteristics 
(e.g., materials, construction, and tread design) influence durability, 
traction (both wet and dry grip), vehicle handling, ride comfort, and 
noise in addition to rolling resistance.
    The agencies explained that a typical Low Rolling Resistance (LRR) 
tire's attributes, compared to a non-LRR tire, would include increased 
tire inflation pressure; material changes; and tire construction with 
less hysteresis, geometry changes (e.g., reduced height to width aspect 
ratios), and reduction in sidewall and tread deflection. When a 
manufacturer applies LRR tires to a vehicle, the manufacturer generally 
also makes changes to the vehicle's suspension tuning and/or suspension 
design in order to maintain vehicle handling and ride comfort.
    The agencies also explained that while LRR tires can be applied to 
vehicles in all MD/HD classes, they may have special potential for 
improving fuel efficiency and reducing CO2 emissions for 
vocational vehicles. According to an energy audit conducted by Argonne 
National Lab, tires are the second largest contributor to energy losses 
of vocational vehicles, after engines.\123\ Given this finding, the 
agencies considered the availability of LRR tires for vocational 
applications by examining the population of tires available, and 
concluded that there appeared to be few LRR tires for vocational 
applications. The agencies suggested in the NPRM that this low number 
of LRR tires for vocational vehicles could be due in part to the fact 
that the competitive pressure to improve rolling resistance of 
vocational vehicle tires has been less than in the line haul tire 
market, given that line haul vehicles generally drive significantly 
more miles and therefore have significantly higher operating costs for 
fuel than vocational vehicles, and much greater incentive to improve 
fuel consumption. The small number of LRR tires for vocational vehicles 
may perhaps also be due in part to the fact that vocational vehicles 
generally operate more frequently on secondary roads, gravel roads and 
roads that have less frequent winter maintenance, which leads 
vocational vehicle buyers to value tire traction and durability more 
than rolling resistance. The agencies recognized that this provided an 
opportunity to improve fuel consumption and GHG emissions by creating a 
regulatory program that encourages improvements in tire rolling 
resistance for both line haul and vocational vehicles. The agencies 
proposed to base standards for all segments of HD vehicles on the use 
of LRR tires. The agencies estimated that a 10 percent reduction in 
average tire rolling resistance would be attainable between model years 
2010 and 2014 based on the tire development achievements over the last 
several years in the line haul truck market. This reduction in tire 
rolling resistance would correlate to a two percent reduction in fuel 
consumption as modeled by the GEM.\124\
---------------------------------------------------------------------------

    \123\ A Class 6 pick up and delivery truck at 50% load has tires 
as the second largest contributor at speeds up to 35 mph, a typical 
average speed of urban delivery vehicles. See Argonne National 
Laboratory. ``Evaluation of Fuel Consumption Potential of Medium and 
Heavy Duty Vehicles through Modeling and Simulation.'' October 2009. 
Page 91.
    \124\ See 75 FR at 74241.
---------------------------------------------------------------------------

(i) Summary of Comments
    The agencies received many comments on the subject of tire rolling 
resistance as applied to vocational vehicles. Comments included 
suggestions for alternative test procedures; whether LRR tires should 
be applied to certain types of vocational vehicles and whether certain 
vehicles should be exempted from the vocational vehicle standards if 
the standards are based on the ability to use LRR tires; the 
appropriateness of the proposed standards; and compliance issues 
(discussed below in Section II.D.2.b.
    Regarding whether LRR tires should be applied to certain types of 
vocational vehicles, the agencies received many comments from 
stakeholders, such as Daimler Trucks North America, Fire Apparatus 
Manufacturers Association (FAMA), International Association of Fire 
Chiefs, National Ready Mix, National Solid Wastes Management 
Association (NSWMA), Spartan Motors, National Automobile Dealers 
Association, among others. There were comments regarding applicability 
of low rolling resistance tires to vocational vehicles based on LRR 
tire availability, suitability of the tires for the applications, fuel 
consumption and GHG emissions benefits and the appropriateness of 
standards. Many of these commenters focused particularly on the whether 
LRR tires would compromise the capability of emergency vehicles.
    Regarding whether LRR tires are available in the market for certain 
vocational vehicles and whether the vocational vehicle standards were 
therefore appropriate and feasible, both Ford and AAPC stated that the 
proposed model-based requirement for Class 2b-8 vocational chassis 
appeared to require tires with rolling resistance values of 
approximately 8.0-8.1 kg/metric ton or better, and that limited data 
available for smaller diameter tires, such as light-truck (LT) tires 
used on many light heavy-duty trucks and vans, suggested that there 
exist few if any choices for tires that would comply. Given this 
concern about the availability of compliant tires, particularly in the 
case of tires smaller than 22.5'', during the proposed regulatory time 
frame, AAPC and Ford requested revisions to the requirement, or the 
modeling method, to establish different standards for vehicles

[[Page 57172]]

that use different tire classes, with separate requirements for LT 
tires, 19.5'' tires, and 22.5'' tires. AAPC argued that standards 
should be set based on data collected on high volume in-use tires, and 
that they should be set at a level that ensures the availability of 
multiple compliant tires. CRR
(ii) Summary of Research Done Since the Notice of Proposed Rulemaking
    Since the NPRM, the agencies have conducted additional research on 
tire rolling resistance for medium- and heavy-duty applications. This 
research involved direct discussions with tire suppliers,\125\ 
assessment of the comments received, additional review of tire products 
available, and a more thorough review of tire use in the field. In 
addition, EPA has conducted tire rolling resistance testing to help 
inform the final rulemaking.\126\
---------------------------------------------------------------------------

    \125\ Records of these communications, and additional 
information submitted by the supplier companies and not CBI, are 
available at Docket No. EPA-HQ-OAR-2010-0162.
    \126\ Bachman, Joseph. Memorandum to the Docket. Heavy-Duty Tire 
Evaluation. July 2011. Docket EPA-HQ-OAR-2010-0162, Pages 3-6.
---------------------------------------------------------------------------

    The agencies discussed many aspects of low rolling resistance tire 
technologies and their application to vocational vehicles with tire 
suppliers since publication of the NPRM. Several tire suppliers 
indicated to the agencies that low rolling resistance tires are 
currently available for vocational applications that would enable 
compliance with the proposed vocational vehicle standards, such as 
delivery vehicles, refuse vehicles, and other vocations. However, these 
conversations also made the agencies aware that availability of low 
rolling resistance tires varies by supplier. Some suppliers stated they 
focused their company resources on areas of the medium- and heavy-duty 
vehicle spectrum where fleet operators would see the most fuel 
efficiency benefits for the application of low rolling resistance 
technologies; specifically the long-haul, on-highway applications that 
drive many miles and use large amounts of fuel. These suppliers stated 
that this choice was driven by the significant capital investment that 
would be needed to improve tire rolling resistance across the 
relatively large number of product offerings in the vocational vehicle 
segment, based on the wide range of tire sizes, load ratings, and speed 
ratings, compared to the much narrower range of offerings for long-haul 
applications.\127\ Other suppliers stated that they have made conscious 
efforts to reduce the rolling resistance of all of their medium- and 
heavy-duty vehicle tire offerings, including vocational applications, 
in an effort to become leaders in this technology.
---------------------------------------------------------------------------

    \127\ More tire types and sizes have been developed for 
vocational vehicle applications than for long-haul applications. In 
some cases, suppliers offer up to 17 different vocational tire 
designs, and for each design there may be 8-10 different tire sizes. 
In contrast, a line-haul application may have only 2-3 tire designs 
with a fewer range of sizes.
---------------------------------------------------------------------------

    The agencies also discussed with tire suppliers the potential tire 
attribute tradeoffs that may be associated with incorporating designs 
that improve tire rolling resistance, given the driving patterns, 
environmental conditions, and on-road and off-road surface conditions 
that vocational vehicles are subjected to. Some vehicle manufacturer 
commenters had suggested that changes in tire tread block design that 
improve rolling resistance may adversely affect tire performance 
characteristics such as traction, resistance to tearing, and resistance 
to wear and damage from scrubbing on curbs and frequent tight radius 
turns that are important to customers for vocational vehicle 
performance. The suppliers agreed that providing tires unable to 
withstand these conditions or meet the vehicle application needs would 
adversely affect customer satisfaction and warranty expenses, and would 
have detrimental financial effects to their businesses. One supplier 
indicated that theoretically, tread-wear (tire life) could be 
compromised if suppliers choose to reduce the initial tire tread depth 
without any offsetting tire compound or design enhancements as the 
means to achieve rolling resistance reductions. That supplier argued 
that taking this approach could lead to more frequent tire replacements 
or re-treading of existing tire carcasses, and that the agencies should 
therefore take a total lifecycle view when evaluating the effects of 
driving rolling resistance reductions. That supplier also indicated 
that a correlation of a 20 percent reduction in rolling resistance 
achieved through tread depth reduction could lead to a 30 percent 
decrease in tread-life and 15 percent reduction in wet traction. The 
agencies note that when they inquired about potential `safety' related 
tradeoffs, such as traction (braking and handling) and tread wear when 
applying low rolling resistance technologies, tire suppliers which 
remain subject to safety standards regardless of this program, 
consistently responded that they would not produce a tire that 
compromises safety when fitted in its proper application.
    In addition to the supplier discussions and evaluation of comments 
to the Notice of Proposed Rulemaking, EPA conducted a series of tire 
rolling resistance tests on medium- and heavy-duty vocational vehicle 
tires. The testing measured the CRR of tires representing 16 different 
vehicle applications for Class 4-8 vocational vehicles. The testing 
included approximately 5 samples each of both steer and drive tires for 
each application. The tests were conducted by two independent tire test 
labs, Standards Testing Lab (STL) and Smithers-Rapra (Smithers).
    Overall, a total of 156 medium- and heavy-duty tires\128\ were 
included in this testing, which was comprised of 88 tires covering 
various commercial vocational vehicle types, such as bucket trucks, 
school buses, city delivery vehicles, city transit buses and refuse 
haulers among others; 47 tires intended for application to tractors; 
and 21 tires classified as light-truck (LT) tires intended for Class 4 
vocational vehicles such as delivery vans. In addition, approximately 
20 of the tires tested were exchanged between the labs to assess inter-
laboratory variability.
---------------------------------------------------------------------------

    \128\ After the agencies completed their analysis of these data, 
the agencies received raw data on 43 additional tires. See Powell, 
Greg. Memorandum to the Docket. Additional Tire Testing Results. 
July 2011. Docket NHTSA-2010-0079. The agencies have not analyzed 
these additional data, nor included them in the final report, and 
the data therefore played no role in the agencies' determination of 
an appropriate standard for vocational vehicles. The agencies will 
analyze and consider these data, along with any future data received 
through continued testing, as appropriate, in the next rulemaking 
for the heavy duty sector.
---------------------------------------------------------------------------

    The test results for 88 commercial vocational vehicle tires (19.5'' 
and 22.5'' sizes) showed a test average CRR of 7.4 kg/metric ton, with 
results ranging from 5.1 to 9.8. To comply with the proposed vocational 
vehicle fuel consumption and GHG emissions standards using improved 
tire rolling resistance as the compliance strategy, a manufacturer 
would need to achieve an average tire CRR value of 8.1 kg/metric 
ton.\129\ The measured average CRR of 7.4kg/metric ton is thus better 
than the average value that would be needed to meet vocational vehicle 
standards. Of those 173 tires tested, twenty tires had CRR values 
exceeding 8.1 kg/metric ton, two were at 8.1 kg/metric ton, and sixty-
six tires were better than 8.1 kg/metric ton. Additional data analyses 
examining the tire data by tire size to determine the range and 
distribution of CRR values within each tire size showed each tire size 
generally had tires ranging from approximately 6.0 to 8.5 kg/metric 
ton, with a small number of tires in the 5.3-5.7 kg/metric ton range 
and a small

[[Page 57173]]

number of tires in a range as high as 9.3-9.8 kg/ton. Review of the 
data showed that for each tire size and vehicle type, the majority of 
tires tested would enable compliance with vocational vehicle fuel 
consumption and GHG emission standards.
---------------------------------------------------------------------------

    \129\ See 75 FR at 74244.
---------------------------------------------------------------------------

    The test results for the 47 tires intended for tractor application 
showed an overall average of 6.9 kg/ton, the lowest overall average 
rolling resistance of the different tire applications tested.\130\ This 
is consistent with what the agencies heard through comments and 
meetings with tire suppliers whose efforts have focused on tractor 
applications, particularly for long-haul applications, which yield the 
highest fuel efficiency benefits from LRR tire technology.
---------------------------------------------------------------------------

    \130\ The CRR values for these applications ranged from 5.4 to 
9.2 kg/metric ton.
---------------------------------------------------------------------------

    Finally, the 21 LT tires intended for Class 4 vocational vehicles 
were comprised of two sizes; LT225/75R16 and LT245/75R16 with 11 and 10 
samples tested, respectively. Some auto manufacturers have indicated 
that CRR values for tires fitted to these Class 4 vehicles typically 
have a higher CRR values than tires found on commercial vocational 
vehicles because of the smaller diameter wheel size and the ISO testing 
protocol.\131\ The test data showed the average CRR for LT225/75R16 
tires was 9.1 kg/metric ton and the average for LT245/75R16 tires was 
8.6 kg/metric ton. The range for the LT225/75R16 tires spanned 7.4 to 
11.0 \132\ and the range for the LT245/75R16 tires ranged from 6.6 to 
9.8 kg/metric ton. Overall, the average for the tested LT tires was 8.9 
kg/metric ton.
---------------------------------------------------------------------------

    \131\ See comments to docket EPA-HQ-OAR-2010-0162-1761; Ford 
Motor Company
    \132\ The agency notes the highest CRR values recorded for LT 
tires, of 11.0 and 10.9, were for two tires of the same size and 
brand. The nearest recorded values to these two tires were 9.8; 
substantially beyond the differences between other tires tested.
---------------------------------------------------------------------------

    Analysis of the EPA test data for all vocational vehicles, 
including LT tires, shows the test average CRR is 7.7 kg/metric ton 
with a standard deviation of 1.2 kg/metric ton. Review of the data thus 
shows that for each tire size and vehicle type, there are many tires 
available that would enable compliance with the proposed standards for 
vocational vehicles and tractors except for LT tires for Class 4 
vocational vehicles where test results show the majority of these tires 
have CRR worse than 8.1 kg/metric ton.
    The agencies also reviewed the CRR data from the tires that were 
tested at both the STL and Smithers laboratories to assess inter-
laboratory and test machine variability. The agencies conducted 
statistical analysis of the data to gain better understanding of lab-
to-lab correlation and developed an adjustment factor for data measured 
at each of the test labs. When applied, this correction factor showed 
that for 77 of the 80 tires tested, the difference between the original 
CRR and a value corrected CRR was 0.01 kg/metric ton. The values for 
the remaining three tires were 0.03 kg/metric ton, 0.05 kg/metric ton 
and 0.07 kg/metric ton. Based on these results, the agencies believe 
the lab-to-lab variation for the STL and Smithers laboratories would 
have very small effect on measured CRR values. Further, in analyzing 
the data, the agencies considered both measurement variability and the 
value of the measurements relative to proposed standards. The agencies 
concluded that although laboratory-to-laboratory and test machine-to-
test machine measurement variability exists, the level observed is not 
excessive relative to the distribution of absolute measured CRR 
performance values and relative to the proposed standards. Based on 
this, the agencies concluded that the test protocol is reasonable for 
this program, but are making some revisions to the vehicle standards.
    The agencies also conducted a winter traction test of 28 tires to 
evaluate the impact of low rolling resistance designs on winter 
traction. The results of the study indicate that there was no 
statistical relationship between rolling resistance and snow 
traction.\133\
---------------------------------------------------------------------------

    \133\ Bachman, Joseph. Memorandum to Docket. Heavy-Duty Tire 
Evaluation. Docket EPA-HQ-OAR-2010-0162. Pages 3-6.
---------------------------------------------------------------------------

(iii) Summary of Final Rules
    For vocational vehicles, the agencies intend to keep rolling 
resistance as an input to the GEM but with modifications to the 
proposed targets as a result of the testing completed by EPA since the 
NPRM and information from tire suppliers. The agencies continue to 
believe that LRR tires, which are an available, cost-effective, and 
appropriate technology with demonstrated fuel efficiency and GHG 
reduction benefits, are reasonable for all on-highway vehicles.
    The agencies acknowledge there can be tradeoffs when designing a 
tire for reduced rolling resistance. These tradeoffs can include 
characteristics such as wear resistance, cost and scuff resistance. 
However, the agencies have continued to review this issue and do not 
believe that LRR tires as specified in the rules present safety issues. 
The agencies continue to believe that LRR tires, which are an 
available, cost-effective, and appropriate technology with demonstrated 
fuel efficiency and GHG reduction benefits, are reasonable for all on-
highway vehicles. The final program also provides exemptions for 
vehicles meeting ``low-speed'' or ``off-road'' criteria, including 
application of speed restricted tires. Vocational vehicles that have 
speed restricted tires in order to accommodate particular applications 
may be exempted from the program under the off-road or low-speed 
exemption, described in greater detail below in Section 
II.D.(1)(a)(iv).
    As just noted, the agencies conducted independent testing of 
current tires available to assist confirming the finalized rolling 
resistance standards. The tire test samples were selected from those 
currently available on the market and therefore have no known safety 
issues and meet all current requirements to allow availability in 
commerce; including wear, scuff resistance, braking, traction under wet 
or icy conditions, and other requirements. These tires included a wide 
array of sizes and designs intended for most all vocational 
applications, including those used for school buses, refuse haulers, 
emergency vehicles, concrete mixers, and recreational vehicles. As the 
test results revealed, there are a significant number of tires 
available that meet or do better than the rolling resistance targets 
for vocational vehicles; both light-truck (with an adjustment factor 
described later in this preamble section) and non-LT tire types, while 
meeting all applicable safety standards.
    The agencies also recognize the extreme conditions fire apparatus 
equipment must navigate to enable firefighters to perform their duties. 
As described below, the final rules contain provisions to allow for 
exemption of specific off-road capable vocational vehicles from the 
fuel efficiency and greenhouse gas standards. Included in the exemption 
criteria are provisions for vehicles equipped with specific tire types 
that would be fit to a vehicle to meet extreme demands, including those 
vehicles designed for off-road capability.
    As follow-up to the final rules and in support for development of a 
separate FMVSS rule, NHTSA plans to conduct additional performance-
focused testing (beyond rolling resistance) for medium- and heavy-duty 
trucks. This testing is targeted for completion toward the end of this 
year. The agencies will review these performance data when available, 
in concert with any subsequent proposed rulemakings regarding fuel 
consumption and GHG emissions

[[Page 57174]]

standards for medium- and heavy-duty vehicles.
    For vocational vehicles, the rolling resistance of each tire will 
be measured using the ISO 28850 test method for drive tires and steer 
tires planned for fitment to the vehicle being certified. Once the test 
CRR values are obtained, a manufacturer will input the CRR values for 
the drive and steer tires separately into the GEM where, for vocational 
vehicles, the vehicle load is distributed equally over the steer and 
drive tires. Once entered, the amount of GHG reduction attributed to 
tire rolling resistance will be incorporated into the overall vehicle 
compliance value. The following table provides the revised target CRR 
values for vocational vehicles for 2014 and 2017 model years that are 
used to determine the vehicle standards.

    Table II-14--Vocational Vehicle--Target CRR Values for GEM Input
------------------------------------------------------------------------
                                        2014 MY             2017 MY
------------------------------------------------------------------------
Tire Rolling Resistance (kg/      7.7 kg/metric ton.  7.7 kg/metric ton
 metric ton).
------------------------------------------------------------------------

    These target values are being revised based on the significant 
availability of tires for vocational vehicles applications which have 
performance better than the originally proposed 8.1 kg/metric ton 
target. As just discussed, 63 of the 88 tires tested for vocational 
applications had CRR values better than the proposed target. The tires 
tested covered fitment to a wide range of vocational vehicle types and 
classes; thus agencies believe the original target value of 8.1 kg/
metric ton was possibly too lenient after reviewing the testing data. 
Therefore, the agencies believe it is appropriate to reduce the 
proposed vehicle standard based on performance of a CRR target value of 
7.7 kg/metric ton for non-LT tire type. As discussed previously, this 
value is the test average of all vocational tires tested (including LT) 
which takes a conservative approach over setting a target based on the 
average of only the non-LT vocational tires tested. For LT tires, based 
on both the test data and the comments from AAPC and Ford Motor 
Company, the agencies recognize the need to provide an adjustment. In 
lieu of having two sets of Light Heavy-Duty vocational vehicle 
standards, the agencies are finalizing an adjustment factor which 
applies to the CRR test results for LT tires. The agencies developed an 
adjustment factor dividing the overall vocational test average CRR of 
7.7 by the LT vocational average of 8.9. This yields an adjustment 
factor of 0.87. For LT vocational vehicle tires, the measured CRR 
values will be multiplied by the 0.87 adjustment factor before entering 
the values in the GEM for compliance.
    Based on the tire rolling resistance inputs noted above, EPA is 
finalizing the following CO2 standards for the 2014 model 
year for the Class 2b through Class 8 vocational vehicle chassis, as 
shown in Table II-15. Similarly, NHTSA is finalizing the following fuel 
consumption standards for the 2016 model year, with voluntary standards 
beginning in the 2014 model year. For the EPA GHG program, the standard 
applies throughout the useful life of the vehicle. The agencies note 
that both the baseline performance and standards derived for the final 
rules slightly differ from the values derived for the NPRM. The first 
difference is due to the change in the target rolling resistance from 
8.1 to 7.7 kg/metric ton based on the agencies' test results. Second, 
there are minor differences in the fuel consumption and CO2 
emissions due to the small modifications made to the GEM, as noted in 
RIA Chapter 4. Lastly, the final HHD vocational vehicle standard uses a 
revised payload assumption of 15,000 pounds instead of the 38,000 
pounds used in the NPRM, as described in Section II.D.3.c.iii. As a 
result, the emission standards shown in Table II-15 for vocational 
vehicles have changed from the standards published in the NPRM. The 
changes for light heavy and medium heavy-duty vehicles are modest. The 
change for heavy heavy-duty vocational vehicles is larger, due to the 
difference in assumed payload.
    As with the 2017 MY standards for Class 7 and 8 tractors, EPA and 
NHTSA are adopting more stringent vocational vehicle standards for the 
2017 model year which reflect the CO2 emissions reductions 
required through the 2017 model year engine standards. See also Section 
II.B.2 explaining the same approach for the standards for combination 
tractors. As explained in Section 0 below, engine performance is one of 
the inputs into the GEM compliance model that has a pre-defined (i.e. 
fixed) value established by the agencies, and that input will change in 
the 2017 MY to reflect the 2017 MY engine standards. The 2017 MY 
vocational vehicle standards are not premised on manufacturers 
installing additional vehicle technologies, and a vocational vehicle 
that complies with the standards in MY 2016 will also comply in MY 2017 
with no vehicle (tire) changes. Thus, although chassis manufacturers 
will not be required to make further improvements in the 2017 MY to 
meet the standards, the standards will be more stringent to reflect the 
engine improvements required in that year. This is because in 2017 MY 
GEM vehicle modeling outputs (in grams per ton mile and gallons per 
1,000 ton mile) will automatically decrease since engine efficiency 
will improve in that year.

               Table II-15--Final Class 2b-8 Vocational Vehicle CO2 and Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
 
----------------------------------------------------------------------------------------------------------------
                           EPA CO2 (gram/ton-mile) Standard Effective 2014 Model Year
----------------------------------------------------------------------------------------------------------------
                                       Light Heavy-Duty Class   Medium Heavy-Duty Class  Heavy Heavy-Duty Class
                                        2b-5.                    6-7.                     8
----------------------------------------------------------------------------------------------------------------
CO2 Emissions........................  388....................  234....................  226
----------------------------------------------------------------------------------------------------------------
           NHTSA Fuel Consumption (gallon per 1,000 ton-mile) Standard Effective 2016 Model Year \134\
----------------------------------------------------------------------------------------------------------------
                                       Light Heavy-DutyClass    Medium Heavy-Duty Class  Heavy Heavy-Duty Class
                                        2b-5.                    6-7.                     8
----------------------------------------------------------------------------------------------------------------
Fuel Consumption.....................  38.1...................  23.0...................  22.2
----------------------------------------------------------------------------------------------------------------
                           EPA CO2 (gram/ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
                                       Light Heavy-Duty Class   Medium Heavy-Duty Class  Heavy Heavy-Duty Class
                                        2b-5.                    6-7.                     8
----------------------------------------------------------------------------------------------------------------
CO2 Emissions........................  373....................  225....................  222
----------------------------------------------------------------------------------------------------------------

[[Page 57175]]

 
                 NHTSA Fuel Consumption (gallon per ton-mile) Standard Effective 2017 Model Year
----------------------------------------------------------------------------------------------------------------
                                       Light Heavy-Duty Class   Medium Heavy-Duty Class  Heavy Heavy-Duty Class
                                        2b-5.                    6-7.                     8
----------------------------------------------------------------------------------------------------------------
Fuel Consumption.....................  36.7...................  22.1...................  21.8
----------------------------------------------------------------------------------------------------------------

(iv) Off-Road and Low-Speed Vocational Vehicle Standards
    Some vocational vehicles, because they are primarily designed for 
off-road use, may not be good candidates for low rolling resistance 
tires. These vehicles may travel on-road for very limited periods of 
time, such as in traveling on an urban road, or if they are off-loaded 
from another vehicle onto a road and then are driven off-road. The 
infrequent and limited exposure to on-road environments makes these 
vehicles suitable candidates for providing an exemption from the 
CO2 emissions and fuel consumption standards for vocational 
vehicles (although the standards for HD engines used in vocational 
vehicles would still apply).\135\ The agencies are also targeting other 
vehicles that travel at low speeds and that are meant to be used both 
on- and off-road. The application of certain technologies to these 
vehicles may not provide the same level of benefits as it would for 
pure on-road vehicles, and moreover, could even reduce the 
functionality of the vehicle. In this case, the agencies want to ensure 
that vehicle functionality is maintained to the maximum extent 
possible, while avoiding the possibility that achievable benefits are 
not realized because of the structure of the regulations. The sections 
below explain this issue in more detail as it applies to tractors and 
vocational vehicles.
---------------------------------------------------------------------------

    \134\ Manufacturers may voluntarily opt-in to the NHTSA fuel 
consumption program in 2014 or 2015. Once a manufacturer opts into 
the NHTSA program it must stay in the program for all the optional 
MYs.
    \135\ See 75 FR at 74199.
---------------------------------------------------------------------------

    The agencies explained in the NPRM that certain vocational vehicles 
have very limited on-road usage, and that although they would be 
defined as ``motor vehicles'' per 40 CFR 85.1703, the fact that they 
spend the most of their operations off-road might be reason for 
excluding them from the vocational vehicle standards. Vocational 
vehicles, such as those used on oil fields and construction sites,\136\ 
experience very little benefit from LRR tires or from any other 
technologies to reduce GHG emissions and fuel consumption. The agencies 
proposed to allow a narrow range of these de facto off-road vehicles to 
be excluded from the proposed vocational vehicle standards if equipped 
with special off-road tires having lug type treads. The agencies stated 
in the NPRM that on/off road traction is the only tire performance 
parameter which trades off with TRR so significantly that tire 
manufacturers could be unable to develop tires meeting both a TRR 
standard while maintaining or improving the characteristic allowing 
them to perform off-road. See generally 75 FR at 74199-200. Therefore, 
the agencies proposed to exempt these vehicles from the standards while 
requiring them to use certified engines, which would provide fuel 
consumption and CO2 emission reductions in all vocational 
applications. To ensure that these vehicles were in fact used chiefly 
off-road, the agencies proposed requirements that would allow exemption 
of a vehicle provided the vehicle and the tires were speed restricted. 
As mentioned, the agencies were aware that the majority of off road 
trucks primarily use off-road tires and are low speed vehicles as well. 
Based upon this understanding, the agencies specifically proposed that 
a vehicle must meet the following requirements to qualify for an 
exemption from vocational vehicle standards:
---------------------------------------------------------------------------

    \136\ Vehicles such as concrete mixers, off-road dump trucks, 
backhoes and wheel loaders.
---------------------------------------------------------------------------

     Tires which are lug tires or contain a speed rating of 
less than or equal to 60 mph; and
     A vehicle speed limiter governed to 55 mph.
    In response to the NPRM, EMA/TMA, Navistar and Volvo agreed with 
the proposal to exclude off-road vocational vehicles from the standards 
because these vehicles primarily operate off-road, but requested 
broadening the exclusion to cover other types of vocational vehicles. 
Several manufacturers (IAFC, FAMA, NTEA, NSWMA, AAPC, RMA, Navistar and 
DTNA) requested the exemption of specific vehicle types, such as on/
off-road emergency vehicles, refuse vehicles, low speed transit buses 
or school buses, because their usage was viewed as being incompatible 
with LRR tires. Navistar opposed the application of the proposed 
regulations to school buses, arguing that LRR tires may impact the ride 
quality for children in school buses. However, Navistar also 
acknowledged that a significant portion of the national fleet of school 
buses already utilizes off-road tires designed with lug type tread 
patterns (e.g., Kentucky). IAFC, FAMA and NTEA commented that fire 
trucks and ambulances should also be exempted due to their part-time 
off-road use such as in responding to a wildland fire or hazardous 
materials incidents which would require operations on dirt and gravel 
roads, fields or other off-road environments. Commenters also contended 
that by requiring a 55-mph limitation, the proposed exemption would be 
impractical for emergency vehicles due to the need to respond quickly 
to life-threatening events. The refuse truck manufacturers and trade 
associations, NSWMA and AAPC, commented that the solid waste industry 
operates a variety of vocational vehicles that perform solely off-road 
at landfills. These comments also requested an exemption for certain 
refuse trucks (i.e., roll-off container trucks) that frequently go off-
road at construction sites. Other commenters (FAMA, IAFC and Oshkosh) 
opposed compliance with the LRR standard for vocational vehicles for 
on/off road mixed service tires with aggressive or lug treads, stating 
that up to this point the industry has had very little interest in 
improving the LRR aspects of these tires or even to conducting testing 
to determine values for the coefficient of rolling resistance.
    For the final rules, the agencies have considered the issues raised 
by commenters and have decided to adopt different criteria than 
proposed for exempting vocational vehicles and vocational tractors that 
primarily travel off-road. The agencies believe that the reasons for 
proposing the exemption are equally applicable to a wider class of 
vocational vehicles operating mostly off-road so that the proposals 
were either unsuitable for the industry or too restrictive to capture 
all the vehicles intended for the exemption. For example, the NPRM 
proposal, by using tire tread patterns and VSLs as the basis for 
qualifying vehicles for the exemption, was too restrictive because 
other non-lug type tread patterns exist in the market as well as other 
technologies which are equally capable of limiting the speed of the 
vehicle, as mentioned by Volvo. Therefore, the

[[Page 57176]]

proposed exemption for off-road vocational vehicles will be replaced 
with new criteria based on the vehicle application, whether it operates 
at low speed and whether the vehicle has speed restricted tires. The 
exemption is in part based on existing industry standards established 
by NHTSA.\137\ As such, any vocational vehicle including vocational 
tractors primarily used off-road or at low speeds must meet the 
following criteria to be exempt from GHG and fuel consumption vehicle 
standards:
---------------------------------------------------------------------------

    \137\ The heavy-duty off-road exemption is based in part on 
requirements existing in NHTSA's Federal Motor Vehicle Safety 
Standards (FMVSS) Nos. 119 and 121. In FMVSS No. 119, titled ``New 
pneumatic tires for motor vehicles with a GVWR of more than 4,538 
kilograms (10,000 pounds) and motorcycles,'' speed restricted tires 
rated at a speed of 55 mph or less are subjected to lower test drum 
speeds in the endurance test to account for their low design speeds 
(e.g., off-road tires). The off-road vehicle exemptions adopted for 
this heavy-duty program were based on the requirements used in FMVSS 
No. 121, ``Air brake systems,'' to identify and exclude vocational 
vehicles based upon their inability to meet on-highway stopping 
distance requirements.
---------------------------------------------------------------------------

     Any vehicle primarily designed to perform work off-road 
such as in oil fields, forests, or construction sites and having 
permanently or temporarily affixed components designed to work in an 
off-road environment (i.e., hazardous material equipment or off-road 
drill equipment) or vehicles operating at low speeds making them 
unsuitable for normal highway operation; and meeting one or more of the 
following criteria:
     Any vehicle equipped with an axle that has a gross axle 
weight rating (GAWR) of 29,000 pounds; or
     Any truck or bus that has a speed attainable in 2 miles of 
not more than 33 mph; or
     Any truck that has a speed attainable in 2 miles of not 
more than 45 mph, an unloaded vehicle weight that is not less than 95 
percent of its gross vehicle weight rating (GVWR), and no capacity to 
carry occupants other than the driver and operating crew.
    The agencies are also adopting in the final rules provisions to 
exempt any vocational vehicle that can operate in both on and off-road 
environments and has speed restricted tires rated at 55 mph or 
below.\138\ The agencies' reasoning in adopting a speed restricted 
exemption for tires is that the majority of mixed service tires used 
for off-road use was identified as being restricted at 55 mph or 
less.\139\ Also, as identified by FMVSS No. 119, speed restricted tires 
at a rating of 55 mph or less are incapable of meeting the same on-road 
performance standards as conventional tires. The agencies acknowledge 
that using a speed restriction criteria could allow certain vehicles to 
be exempted inappropriately (i.e., low speed city delivery tractors) 
but the agencies believe this is preferable to creating a situation 
where a segment of vehicles are precluded from performing their 
intended applications. Therefore, the final rules include an exemption 
for any mixed service (on and off-road) vocational vehicle equipped 
with off-road tires that are speed restricted at 55 mph or less.
---------------------------------------------------------------------------

    \138\ See 40 CFR 1037.631.
    \139\ Particular tire use was identified during the FMVSS 119 
rulemaking and confirmed through subsequent market research. See 
``2010 Year Book the Tire and RIM Association Inc.''
---------------------------------------------------------------------------

    Manufacturers choosing to exempt vehicles based on the above 
criteria will be required to provide a description of how they meet the 
qualifications for each vehicle family group in their end-of-the year 
and final year reports (see Section V).
    A manufacturer having an off-road vehicle failing to meet the 
criteria under the agencies' off-road exemptions will be allowed to 
submit a petition describing how and why their vehicles should qualify 
for exclusion. The process of petitioning for an exemption is explained 
in Sec.  1037.631 and Sec.  535.8. For each request, the manufacturer 
will be required to describe why it believes an exemption is warranted 
and address the following factors which the agencies will consider in 
granting its petition:
     The agencies provide an exemption based on off-road 
capability of the vehicle or if the vehicle is fitted with speed 
restricted tires. Which exemption does your vehicle qualify under; and
     Are there any comparable tires that exist in the market to 
carry out the desired application both on and off road for the subject 
vehicle(s) of the petition which have LLR values that would enable 
compliance with the standard?
(b) Heavy-Duty Engine Standards for Engines Installed in Vocational 
Vehicles
    EPA is finalizing GHG standards \140\ and NHTSA is finalizing fuel 
consumption standards for new heavy-duty engines installed in 
vocational vehicles. The standards will vary depending on whether the 
engines are diesel or gasoline powered since emissions and fuel 
consumption profiles differ significantly depending on whether the 
engine is gasoline or diesel powered. The agencies' analyses, as 
discussed briefly below and in more detail later in this preamble and 
in the RIA Chapter 2, show that these standards are appropriate and 
feasible under each agency's respective statutory authorities.
---------------------------------------------------------------------------

    \140\ Specifically, EPA is finalizing CO2, 
N2O, and CH4 emissions standards for new 
heavy-duty engines over an EPA specified useful life period (See 
Section 0 for the N2O and CH4 standards).
---------------------------------------------------------------------------

    The agencies have analyzed the feasibility of achieving the GHG and 
fuel consumption standards, based on projections of what actions 
manufacturers are expected to take to reduce emissions and fuel 
consumption. EPA and NHTSA also present the estimated costs and 
benefits of the heavy-duty engine standards in Section III below. In 
developing the final rules, the agencies have evaluated the kinds of 
technologies that could be utilized by engine manufacturers compared to 
a baseline engine, as well as the associated costs for the industry and 
fuel savings for the consumer and the magnitude of the GHG and fuel 
consumption savings that may be achieved.
    EPA's existing criteria pollutant emissions regulations for heavy-
duty highway engines establish four service classes (three for 
compression-ignition or diesel engines and one for spark ignition or 
gasoline engines) that represent the engine's intended and primary 
vehicle application, as shown in Table II-16 (40 CFR 1036.140 and 
NHTSA's 49 CFR 535.4). The agencies proposed to use the existing 
service classes to define the engine subcategories in this HD GHG 
emissions and fuel consumption program. The agencies did not receive 
any adverse comments to using this approach. Thus, the agencies are 
adopting the four engine subcategories for this final action.

              Table II-16--Engine Regulatory Subcategories
------------------------------------------------------------------------
            Engine category                    Intended application
------------------------------------------------------------------------
Light Heavy-duty (LHD) Diesel..........  Class 2b through Class 5 trucks
                                          (8,501 through 19,500 pounds
                                          GVWR).
Medium Heavy-duty (MHD) Diesel.........  Class 6 and Class 7 trucks
                                          (19,501 through 33,000 pounds
                                          GVWR).
Heavy Heavy-duty (HHD) Diesel..........  Class 8 trucks (33,001 pounds
                                          and greater GVWR.
Gasoline...............................  Incomplete vehicles less than
                                          14,000 pounds GVWR and all
                                          vehicles (complete or
                                          incomplete) greater than
                                          14,000 pounds GVWR.
------------------------------------------------------------------------

(i) Diesel Engine Standards for Engines Installed in Vocational 
Vehicles
    In the NPRM, the agencies proposed the following CO2 and 
fuel consumption standards for HD diesel engines to be

[[Page 57177]]

installed in vocational vehicles, as shown in Table II-17.

                  Table II-17--Vocational Diesel Engine Standards Over the Heavy-Duty FTP Cycle
----------------------------------------------------------------------------------------------------------------
                                                                   Light heavy-    Medium heavy-   Heavy heavy-
              Model year                        Standard            duty diesel     duty diesel     duty diesel
----------------------------------------------------------------------------------------------------------------
2014-2016.............................  CO2 Standard (g/bhp-hr).             600             600             567
                                        Voluntary Fuel                      5.89            5.89            5.57
                                         Consumption Standard
                                         (gallon/100 bhp-hr).
2017 and Later........................  CO2 Standard (g/bhp-hr).             576             576             555
                                        Fuel Consumption (gallon/           5.66            5.66            5.45
                                         100 bhp-hr).
----------------------------------------------------------------------------------------------------------------

    The agencies explained in the NPRM that the standards were based on 
our assessment of the findings of the 2010 NAS report and other 
literature sources that there are technologies available to reduce fuel 
consumption in all these engines by this level in the final time frame 
in a cost-effective manner. Similar to the technology basis for HD 
engines used in combination tractors, these technologies include 
improved turbochargers, aftertreatment optimization, low temperature 
exhaust gas recirculation, and engine friction reductions.
    The agencies proposed that the HD diesel engine CO2 
standards for vocational vehicles would become effective in MY 2014 for 
EPA, with more stringent CO2 standards becoming effective in 
MY 2017, while NHTSA's fuel consumption standards would become 
effective in MY 2017, which would be both consistent with the EISA 
four-year minimum lead-time requirements and harmonized with EPA's 
timing for stringency increases. The agencies explained that the three-
year timing, besides being required by EISA, made sense because EPA's 
heavy-duty highway engine program for criteria pollutants had begun to 
provide new emissions standards for the industry in three year 
increments, which had caused the heavy-duty engine and vehicle 
manufacturer product plans to fall largely into three year cycles 
reflecting this regulatory environment.\141\ To further harmonize with 
EPA, NHTSA proposed voluntary fuel consumption standards for HD diesel 
engines for vocational vehicles in MYs 2014-2016, allowing 
manufacturers to opt into the voluntary standards in any of those model 
years.\142\ Manufacturers opting into the program must declare by 
statement their intent to comply prior to or at the same time they 
submit their first application for a certificate of conformity. A 
manufacturer opting into the program would begin tracking credits and 
debits beginning in the model year in which they opt in. Both agencies 
proposed to allow manufacturers to generate and use credits to achieve 
compliance with the HD diesel engine standards for vocational vehicles, 
including averaging, banking, and trading (ABT), and deficit carry-
forward.
---------------------------------------------------------------------------

    \141\ See generally 75 FR at 74200-201.
    \142\ Once a manufacturer opts into the NHTSA program it must 
stay in the program for all the optional MYs and remain standardized 
with the implementation approach being used to meet the EPA emission 
program.
---------------------------------------------------------------------------

    The agencies proposed to require HD diesel engine manufacturers to 
achieve, on average, a three percent reduction in fuel consumption and 
CO2 emissions for the 2014 standards over the baseline MY 
2010 performance for the HHD diesel engines, and a five percent 
reduction for the LHD and MHD diesel engines. The standards for the LHD 
and MHD engine categories were proposed to be set at the same level 
because the agencies found that there is an overlap in the displacement 
of engines which are currently certified as LHDD or MHDD. The agencies 
developed the baseline 2010 model year CO2 emissions from 
data provided to EPA by manufacturers during the non-GHG certification 
process. Analysis of CO2 emissions from 2010 model year LHD 
and MHDD diesel engines showed little difference between LHD and MHD 
diesel engine baseline CO2 performance in the 2010 model 
year, which overall averaged 630 g CO2/bhp-hr (6.19 gal/100 
bhp-hr).\143\ Furthermore, the technologies available to reduce fuel 
consumption and CO2 emissions from these two categories of 
engines are similar. The agencies considered combining these engine 
categories into a single category, but decided to maintain these two 
separate engine categories with the same standard level to respect the 
different useful life periods associated with each category.
---------------------------------------------------------------------------

    \143\ Calculated using the conversion 10,180 g CO2/
gallon for diesel fuel.
---------------------------------------------------------------------------

    For vocational engines certified on the FTP cycle, the agencies 
proposed to require a five percent reduction for HHD engines and nine 
percent for LHD and MHD engines. For LHD and MHD engines in 2017 MY, 
the nine percent reduction is based on the assumption that valvetrain 
friction reduction can be achieved in LHD and MHD engines in addition 
to turbo efficiency and accessory (water, oil, and fuel pump) 
improvements, improved EGR cooler, and other approaches being used for 
HHD engines.
    Commenters who discussed the HD diesel engine standards generally 
did not differentiate between the standards for engines used in 
combination tractors and the engines used in vocational vehicles. As 
explained above in Section II.B.2.b, some commenters, such as EMA/TMA, 
Cummins, DTNA, and other manufacturers, supported the proposed 
standards, as long as the flexibilities proposed in the NPRM were 
finalized as proposed. Volvo argued that the standards are being phased 
in too quickly. Environmental groups and NGOs commented that the 
standards should be more stringent and reflect the potential for 
greater fuel consumption and CO2 emissions reductions 
through the use of additional technologies outlined in the 2010 NAS 
study.
    In response to those comments, the agencies refer back to our 
discussion in Section II.B.2.b. The agencies believe that the 
additional reductions may be achieved through the increased development 
of the technologies evaluated for the 2014 model year standard, but the 
agencies' analysis indicates that this type of advanced engine 
development will require a longer development time than MY 2014. The 
agencies are therefore providing additional lead time to allow for the 
introduction of this additional technology, and waiting until 2017 to 
increase stringency to levels reflecting application of 
turbocompounding. See Chapter 2 of the RIA for more details.
    While it made sense to set standards at the same level for LHD and 
MHD diesel engines for vocational vehicles, the agencies found that it 
did not make sense to set HHD standards at the same level. Based on 
manufacturer-submitted

[[Page 57178]]

CO2 data for the non-GHG emissions certification process, 
the agencies found that the baseline for HHD diesel engines was much 
lower than for LHD/MHD diesel engines--584 g CO2/bhp-hr 
(5.74 gal/100 bhp-hr) on average for HHD, compared to 630 g 
CO2/bhp-hr (6.19 gal/100 bhp-hr) on average for LHD/
MHD.\144\ In addition to the differences in the baseline performance, 
the agencies believe that there may be some technologies available to 
reduce fuel consumption and CO2 emissions that may be 
appropriate for the HHD diesel engines but not for the LHD/MHD diesel 
engines, such as turbocompounding. Therefore, the agencies are setting 
a different standard level for HHD diesel engines to be used in 
vocational vehicles. Additional discussion on technical feasibility is 
included in Section III below and in Chapter 2 of the RIA.
---------------------------------------------------------------------------

    \144\ Calculated using the conversion 10,180 g CO2/
gallon for diesel fuel.
---------------------------------------------------------------------------

    After consideration of the comments, EPA and NHTSA are adopting as 
proposed the CO2 emission standards and fuel consumption 
standards for heavy-duty diesel engines installed in vocational 
vehicles are presented in Table II-17. Consistent with proposal, the 
first set of standards take effect with MY 2014 (mandatory standards 
for EPA, voluntary standards for NHTSA), and the second set take effect 
with MY 2017 (mandatory for both agencies).
    Compliance with the standards for engines installed in vocational 
vehicles will be evaluated based on the composite HD FTP cycle. In the 
NPRM, the agencies proposed standards based on the Heavy-duty FTP cycle 
for engines used in vocational vehicles reflecting their primary use in 
transient operating conditions (typified by both frequent accelerations 
and decelerations), as well as in some steady cruise conditions as 
represented on the Heavy-duty FTP. The primary reason the agencies 
proposed two separate certification cycles for HD diesel engines--one 
for HD diesel engines used in combination tractors and the other for HD 
diesel engines used in vocational vehicles--is to encourage engine 
manufacturers to install technologies appropriate to the intended use 
of the engine with the vehicle.\145\
---------------------------------------------------------------------------

    \145\ See generally 75 FR at 74201.
---------------------------------------------------------------------------

    DTNA, Cummins, EMA/TMA, and Honeywell commented that certain 
vocational vehicle applications would achieve greater fuel consumption 
and CO2 emissions reductions in-use by using an engine 
designed to meet the SET-based standard. They stated that some 
vocational vehicles operate at steady-state more frequently than in 
transient operation, such as motor coaches, and thus should be able to 
have an engine certified on a steady-state cycle to better reflect the 
vehicle's real use.
    In response, while the agencies recognize the value to 
manufacturers of having additional flexibility that allows them to meet 
the standards in a way most consistent with how their vehicles and 
engines will ultimately be used, we remain concerned about increasing 
flexibility in ways that might impair fuel consumption and 
CO2 emissions reductions. The agencies are therefore 
providing the option in these final rules for some vocational vehicles, 
but not others, to have SET certified engines. Heavy heavy-duty 
vocational engines will be allowed to be SET certified for vocational 
vehicles, since SET certified HHD engines must meet more stringent GHG 
and fuel consumption standards than FTP certified engines. We believe 
this will provide manufacturers additional flexibility while still 
achieving the expected fuel consumption and CO2 emissions 
reductions. However, medium heavy-duty vocational engines will not be 
allowed to be SET-certified, because medium heavy-duty engines 
certified on the FTP must meet a more stringent standard than engines 
certified on the SET, and the agencies are not confident that fuel 
consumption and CO2 emissions reduction levels would 
necessarily be maintained.
    As discussed above in Section II.B.2.b, the agencies place 
important weight in making our decisions about the cost-effectiveness 
of the standards and the availability of lead time on the fact that 
engine manufacturers are expected to redesign and upgrade their 
products during MYs 2014-2017. The final two-step CO2 
emission and fuel consumption standards recognize the opportunity for 
technology improvements over the rulemaking time frame, while 
reflecting the typical diesel truck manufacturers' and diesel engine 
manufacturers' product plan cycles. Over these four model years there 
will be an opportunity for manufacturers to evaluate almost every one 
of their engine models and add technology in a cost-effective way, 
consistent with existing redesign schedules, to control GHG emissions 
and reduce fuel consumption. The time-frame and levels for the 
standards, as well as the ability to average, bank and trade credits 
and carry a deficit forward for a limited time, are expected to provide 
manufacturers the time needed to incorporate technology that will 
achieve the final GHG and fuel consumption reductions, and to do this 
as part of the normal engine redesign process. This is an important 
aspect of the final rules, as it will avoid the much higher costs that 
would occur if manufacturers needed to add or change technology at 
times other than these scheduled redesigns.\146\ This time period will 
also provide manufacturers the opportunity to plan for compliance using 
a multi-year time frame, again in accord with their normal business 
practice. Further details on lead time, redesigns and technical 
feasibility can be found in Section III.
---------------------------------------------------------------------------

    \146\ See 75 FR at 25467-68.
---------------------------------------------------------------------------

    The agencies recognize, however, that the schedule of changes for 
the final standards may not be the most cost-effective one for all 
manufacturers. For HD diesel engines for use in tractors, the agencies 
discussed above in Section II.B.2.b our decision in this final program 
to allow an ``OBD phase-in'' option for meeting the standards, based on 
comments received from several industry organizations indicating that 
aligning technology changes for multiple regulatory requirements would 
provide them with greater flexibility. In the context of HD diesel 
engines for use in vocational vehicles, Volvo, EMA/TMA, and DDC 
specifically requested an ``OBD phase-in'' option in its comments to 
the NPRM. DDC argued that bundling design changes where possible can 
reduce the burden on industry for complying with regulations, so 
aligning the introduction of the OBD, GHG, and fuel consumption 
standards could help reduce the resources devoted to validation of new 
product designs and certification.
    The agencies have the same interest in providing this flexibility 
for manufacturers of HD diesel engines for use in vocational vehicles 
as in providing it for manufacturers of HD diesel engines for use in 
combination tractors, as long as equivalent emissions and fuel savings 
are maintained. Thus, in order to provide additional flexibility for 
manufacturers looking to align their technology changes with multiple 
regulatory requirements, the agencies are finalizing an alternate ``OBD 
phase-in'' option for meeting the HD diesel engine standards which 
delivers equivalent CO2 emissions and fuel consumption 
reductions as the primary standards for the engines built in the 2013 
through 2017 model years, as shown in Table II-18.

[[Page 57179]]

    Table II-18--Comparison of CO2 reductions for the Engine Standards Under the Alternative OBD Phase-in and
                                                Primary Phase-In
----------------------------------------------------------------------------------------------------------------
                                 HHD FTP                                                LHD/MHD FTP
----------------------------------------------------------------------------------------------------------------
                                                               Difference                             Difference
                                      Primary      Optional   in lifetime    Primary      Optional   in lifetime
                                      phase-in     phase-in    CO2 engine    phase-in     phase-in    CO2 engine
                                    standard (g/ standard (g/  emissions   standard (g/ standard (g/  emissions
                                      bhp-hr)      bhp-hr)       (MMT)       bhp-hr)      bhp-hr)       (MMT)
----------------------------------------------------------------------------------------------------------------
Baseline..........................          584          584  ...........          630          630
2013 MY Engine....................          584          577           20          630          618           14
2014 MY Engine....................          567          577          -28          600          618          -22
2015 MY Engine....................          567          577          -28          600          618          -22
2016 MY Engine....................          567          555           34          600          576           29
2017 MY Engine....................          555          555            0          576          576            0
Net Reductions (MMT)..............  ...........  ...........           -3  ...........  ...........            0
----------------------------------------------------------------------------------------------------------------

     Table II-19 presents the final HD diesel engine CO2 
emission and fuel consumption standards under the optional ``OBD phase-
in'' option.

                            Table II-19--Optional Heavy-Duty Engine Standard Phase-in
----------------------------------------------------------------------------------------------------------------
                                                                   Light heavy-    Medium heavy-   Heavy heavy-
              Model year                        Standard            duty diesel     duty diesel     duty diesel
----------------------------------------------------------------------------------------------------------------
2013..................................  CO2 Standard (g/bhp-hr).             618             618             577
                                        Voluntary Fuel                      6.07            6.07            5.67
                                         Consumption Standard
                                         (gallon/100 bhp-hr).
2016 and Later........................  CO2 Standard (g/bhp-hr).             576             576             555
                                        Fuel Consumption (gallon/           5.66            5.66            5.45
                                         100 bhp-hr).
----------------------------------------------------------------------------------------------------------------

    In order to ensure equivalent CO2 and fuel consumption 
reductions and orderly compliance, and to avoid gaming, the agencies 
are requiring that if a manufacturer selects the OBD phase-in option, 
it must certify its engines starting in the 2013 model year and 
continue using this phase-in through the 2016 model year. Manufacturers 
may opt into the OBD phase-in option through the voluntary NHTSA 
program, but must opt in in the 2013 model year and continue using this 
phase-in through the 2016 model year. Manufacturers that opt in to the 
voluntary NHTSA program in 2014 and 2015 will be required to meet the 
primary phase-in schedule and may not adopt the OBD phase-in option.
    As discussed above in Section II.B.2.b, while the agencies believe 
that the HD diesel engine standards are appropriate, cost-effective, 
and technologically feasible in the rulemaking time frame, we also 
recognize that when regulating a category of engines for the first 
time, there will be individual products that may deviate significantly 
from the baseline level of performance, whether because of a specific 
approach to criteria pollution control, or due to engine calibration 
for specific applications or duty cycles. That earlier discussion 
described HD diesel engines for use in combination tractors, but the 
same supporting information is relevant to the agencies' consideration 
of an alternate standard for HD diesel engines installed in vocational 
vehicles. In the NPRM, the agencies proposed an optional engine 
standard for HD diesel engines installed in vocational vehicles based 
on a five percent reduction from the engine's own 2011 model year 
baseline level, but requested comment on whether a two percent 
reduction would be more appropriate.\147\ The comments received in 
response did not directly address engines for vocational vehicles, but 
the agencies believe that the information provided by Navistar and 
others is equally applicable to HD diesel engines for combination 
tractors and for vocational vehicles. Our assessment for the final 
standards is that a 2.5 percent reduction is appropriate for LHD and 
MHD engines installed in vocational vehicles and 3 percent is 
appropriate for HHD engines installed in vocational vehicles given the 
technologies available for application to legacy products by model year 
2014.\148\ Unlike the majority of engine products in this segment, 
engine manufacturers have devoted few resources to developing 
technologies for these legacy products reasoning that the investment 
would have little value if the engines are to be substantially 
redesigned or replaced in the next five years. Hence, although the 
technologies we have identified to achieve the proposed five percent 
reduction would theoretically work for these legacy products, there is 
inadequate lead time for manufacturers to complete the pre-application 
development needed to add the technology to these engines by 2014. The 
mix of technologies available off the shelf for legacy engines varies 
between engine lines within OEMs and varies among OEMs as well. On 
average, based on our review of manufacturer development history and 
current plans, we project that for the legacy products approximately 
half of the defined technologies appropriate for the 2014 standard will 
be available and ready for application by 2014 for older legacy engine 
designs. Hence, we have concluded that if we limit the reductions to 
those improvements which reflect further enhancements of already 
installed systems rather than the addition or replacement of 
technologies with fully developed new on the shelf components, the 
potential improvement for the 2014 model year will be 2.5 percent for 
LHD and MHD engines and 3 percent HHD engines.
---------------------------------------------------------------------------

    \147\ See 75 FR at 74202.
    \148\ To be codified at 40 CFR 1036.620.
---------------------------------------------------------------------------

    Just as for HD diesel engines used in combination tractors, the 
agencies stress that this option for HD engines used in vocational 
vehicles is temporary and

[[Page 57180]]

limited and is being adopted to address diverse manufacturer needs 
associated with complying with this first phase of the regulations. 
This optional, alternative standard will be available only for the 2014 
through 2016 model years, because we believe that manufacturers will 
have had ample opportunity to make appropriate changes to bring their 
product performance into line with the rest of the industry after that 
time. This optional standard will not be available unless and until a 
manufacturer has exhausted all available credits and credit 
opportunities, and engines under the alternative standard could not 
generate credits.
    The agencies note that manufacturers choosing to utilize this 
option in MYs 2014-2016 will have to make a greater relative 
improvement in MY 2017 than the rest of the industry, since they will 
be starting from a worse level. For compliance purposes, in MYs 2014-
2016 emissions from engines certified and sold at the alternate level 
will be averaged with emissions from engines certified and sold at more 
stringent levels to arrive at a weighted average emissions level for 
all engines in the subcategory. Again, this option can only be taken if 
all other credit opportunities have been exhausted and the manufacturer 
still cannot meet the primary standards. If a manufacturer chooses this 
option to meet the EPA emission standards in MY 2014-2016, and wants to 
opt into the NHTSA fuel consumption program in these same MYs it must 
follow the exact path followed under the EPA program utilizing 
equivalent fuel consumption standards.
    As discussed above in Section II.B.2.b, Volvo argued that 
manufacturers could game the standard by establishing an artificially 
high 2011 baseline emission level. This could be done, for example, by 
certifying an engine with high fuel consumption and GHG emissions that 
is either: (1) Not sold in significant quantities; or (2) later altered 
to emit fewer GHGs and consume less fuel through service changes. In 
order to mitigate this possibility, the agencies are requiring either 
that the 2011 model year baseline must be developed by averaging 
emissions over all engines in an engine averaging set certified and 
sold for that model year so as to prevent a manufacturer from 
developing a single high GHG output engine solely for the purpose of 
establishing a high baseline or meet additional criteria. The agencies 
are allowing manufacturers to combine light heavy-duty and medium 
heavy-duty diesel engines into a single averaging set for this 
provision because the engines have the same GHG emissions and fuel 
consumption standards. If a manufacturer does not certify all engine 
families in an averaging set to the alternate standards, then the 
tested configuration of the engine certified to the alternate standard 
must have the same engine displacement and its rated power within 5 
percent of the highest rated power as the baseline engine. In addition, 
the tested configurations must have a BSFC equivalent to or better than 
all other configurations within the engine family and represent a 
configuration that is sold to customers.
(ii) Gasoline Engine Standard
    Heavy-duty gasoline engines are also used in vocational vehicle 
applications. The number of engines certified in the past for this 
segment of vehicles is very limited and has ranged between three and 
five engine models.\149\ Unlike the heavy-duty diesel engines typical 
of this segment which are built for vocational vehicles, these gasoline 
engines are developed for heavy-duty pickup trucks and vans primarily, 
but are also sold as loose engines to vocational vehicle manufacturers, 
for use in vocational vehicles such as some delivery trucks. Some 
fleets still prefer gasoline engines over diesel engines. In the past, 
this was the case since gasoline stations were more prevalent than 
stations that sold diesel fuel. Because they are developed for HD 
pickups and vans, the agencies evaluated these engines in parallel with 
the heavy-duty pickup truck and van standard development. As in the 
pickup truck and van segment, the agencies anticipated that the 
manufacturers will have only one engine re-design within the 2014-2018 
model years under consideration within the proposal. The agencies 
therefore proposed fuel consumption and CO2 emissions 
standards for gasoline engines for use in vocational vehicles, which 
represent a five percent reduction in CO2 emissions and fuel 
consumption in the 2016 model year over the 2010 MY baseline through 
use of technologies such as coupled cam phasing, engine friction 
reduction, and stoichiometric gasoline direct injection.
---------------------------------------------------------------------------

    \149\ EPA's heavy-duty engine certification database at http://www.epa.gov/otaq/certdata.htm#largeng.
---------------------------------------------------------------------------

    In our meetings with all three of the major manufacturers in the HD 
pickup and van segment, confidential future product plans were shared 
with the agencies. Reflecting those plans and our estimates for when 
engine changes will be made in alignment with those product plans, we 
had concluded for proposal that the 2016 model year reflects the most 
logical model year start date for the heavy-duty gasoline engine 
standards. In order to meet the standards we are finalizing for heavy-
duty pickups and vans, we project that all manufacturers will have 
redesigned their gasoline engine offerings by the start of the 2016 
model year. Given the small volume of loose gasoline engine sales 
relative to complete heavy-duty pickup sales, we think it is 
appropriate to set the timing for the heavy-duty gasoline engine 
standard in line with our projections for engine redesigns to meet the 
heavy-duty pickup truck standards. Therefore, NHTSA's final fuel 
consumption standard and EPA's final CO2 standard for heavy-
duty gasoline engines are first effective in the 2016 model year.
    The baseline 2010 model year CO2 performance of these 
heavy-duty gasoline engines over the Heavy-duty FTP cycle is 660 g 
CO2/bhp-hr (7.43 gal/100 bhp-hr) in 2010 based on non-GHG 
certification data provided to EPA by the manufacturers. The agencies 
are finalizing 2016 model year standards that require manufacturers to 
achieve a five percent reduction in CO2 compared to the 2010 
MY baseline through use of technologies such as coupled cam phasing, 
engine friction reduction, and stoichiometric gasoline direct 
injection. Additional detail on technology feasibility is included in 
Section III and in the RIA Chapter 2. As shown in Table II-20, NHTSA is 
finalizing as proposed a 7.06 gallon/100 bhp-hr standard for fuel 
consumption while EPA is adopting as proposed a 627 g CO2/
bhp-hr standard tested over the Heavy-duty FTP, effective in the 2016 
model year. Similar to EPA's non-GHG standards approach, manufacturers 
may generate and use credits by the same engine averaging set to show 
compliance with both agencies' standards.

            Table II-20--Heavy-Duty Gasoline Engine Standards
------------------------------------------------------------------------
                                                             Gasoline
            Model year                                        engine
                                                             standard
------------------------------------------------------------------------
2016 and Later....................  CO2 Standard (g/bhp-             627
                                     hr).
                                    Fuel Consumption                7.06
                                     (gallon/100 bhp-hr).
------------------------------------------------------------------------

(c) In-Use Standards
    Section 202(a)(1) of the CAA specifies that emissions standards are 
to be applicable for the useful life of the vehicle. The in-use 
standards that EPA

[[Page 57181]]

is finalizing apply to individual vehicles and engines. NHTSA is not 
finalizing in-use standards that would apply to the vehicles and 
engines in a similar fashion.
    EPA proposed that the in-use standards for heavy-duty engines 
installed in vocational vehicles be established by adding an adjustment 
factor to the full useful life emissions results projected in the EPA 
certification process to account for measurement variability inherent 
in testing done at different laboratories with different engines. The 
agency proposed a two percent adjustment factor and requested comments 
and additional data during the proposal to assist in developing an 
appropriate factor level. The agency received additional data during 
the comment period which identified production variability which was 
not accounted for at proposal. Details on the development of the final 
adjustment factor are included in RIA Chapter 3. Based on the data 
received, EPA determined that the adjustment factor in the final rules 
should be higher than the proposed level of two percent. EPA is 
finalizing a three percent adjustment factor for the in-use standard to 
provide a reasonable margin for production and test-to-test variability 
that could result in differences between the initial emission test 
results and emission results obtained during subsequent in-use testing.
    We are finalizing regulatory text (in Sec.  1036.150) to allow 
engine manufacturers to used assigned deterioration factors (DFs) 
without performing their own durability emission tests or engineering 
analysis. However, the engines would still be required to meet the 
standards in actual use without regard to whether the manufacturer used 
the assigned DFs. This allowance is being adopted as an interim 
provision applicable only for this initial phase of standards.
    Manufacturers will be allowed to use an assigned additive DF of 0.0 
g/bhp-hr for CO2 emissions from any conventional engine 
(i.e., an engine not including advance or innovative technologies). 
Upon request, we could allow the assigned DF for CO2 
emissions from engines including advance or innovative technologies, 
but only if we determine that it would be consistent with good 
engineering judgment. We believe that we have enough information about 
in-use CO2 emissions from conventional engines to conclude 
that they will not increase as the engines age. However, we lack such 
information about the more advanced technologies.
    EPA proposed that the useful life for these engines and vehicles 
with respect to GHG emissions be set equal to the respective useful 
life periods for criteria pollutants. EPA proposed that the existing 
engine useful life periods, as included in Table II-21, be broadened to 
include CO2 emissions and fuel consumption for both engines 
and vocational vehicles. The agency did not receive any adverse 
comments with this approach and is finalizing the useful life periods 
as proposed (see 40 CFR 1036.108(d) and 1037.105). While NHTSA will use 
useful life considerations for establishing fuel consumption 
performance for initial compliance and for ABT, NHTSA does not intend 
to implement an in-use compliance program for fuel consumption, because 
it is not required under EISA and because it is not currently 
anticipated there will be notable deterioration of fuel consumption 
over the engines' useful life.

                    Table II-21--Useful Life Periods
------------------------------------------------------------------------
                                               Years           Miles
------------------------------------------------------------------------
Class 2b-5 Vocational Vehicles, Spark                 10         110,000
 Ignited, and Light Heavy-Duty Diesel
 Engines................................
Class 6-7 Vocational Vehicles and Medium              10         185,000
 Heavy-Duty Diesel Engines..............
Class 8 Vocational Vehicles and Heavy                 10         435,000
 Heavy-Duty Diesel Engines..............
------------------------------------------------------------------------

(2) Test Procedures and Related Issues
    The agencies are finalizing test procedures to evaluate fuel 
consumption and CO2 emissions of vocational vehicles in a 
manner very similar to Class 7 and Class 8 combination tractors. This 
section describes the simulation model for demonstrating compliance, 
engine test procedures, and a test procedure for evaluating hybrid 
powertrains (a potential means of generating credits, although not part 
of the technology package on which the final standard for vocational 
vehicles is premised).
(a) Computer Simulation Model
    As previously mentioned, to achieve the goal of reducing emissions 
and fuel consumption for both trucks and engines, we are finalizing 
separate engine and vehicle-based emission and fuel consumption 
standards for vocational vehicles and engines used in those vehicles. 
For the vocational vehicles, engine manufacturers are subject to the 
engine standards, and chassis manufacturers are required to install 
certified engines in their chassis. The chassis manufacturer is subject 
to a separate vehicle-based standard that uses the final vehicle 
simulation model, the GEM, to evaluate the impact of the tire design to 
determine compliance with the vehicle standard.
    A simulation model, in general, uses various inputs to characterize 
a vehicle's properties (such as weight, aerodynamics, and rolling 
resistance) and predicts how the vehicle would behave on the road when 
it follows a driving cycle (vehicle speed versus time). On a second-by-
second basis, the model determines how much engine power needs to be 
generated for the vehicle to follow the driving cycle as closely as 
possible. The engine power is then transmitted to the wheels through 
transmission, driveline, and axles to move the vehicle according to the 
driving cycle. The second-by-second fuel consumption of the vehicle, 
which corresponds to the engine power demand to move the vehicle, is 
then calculated according to the fuel consumption map embedded in the 
compliance model. Similar to a chassis dynamometer test, the second-by-
second fuel consumption is aggregated over the complete drive cycle to 
determine the fuel consumption of the vehicle.
    NHTSA and EPA are finalizing an approach consistent with the 
proposal to evaluate fuel consumption and CO2 emissions 
respectively through a simulation of whole-vehicle operation, 
consistent with the NAS recommendation to use a truck model to evaluate 
truck performance. The EPA developed the GEM for the specific purpose 
of this rulemaking to evaluate vehicle performance. The GEM is similar 
in concept to a number of vehicle simulation tools developed by 
commercial and government entities. The model developed by the EPA and 
finalized here was designed for the express purpose of vehicle 
compliance demonstration and is therefore simpler and less configurable 
than similar

[[Page 57182]]

commercial products. This approach gives a compact and quicker tool for 
evaluating vehicle compliance without the overhead and costs of a more 
complicated model. Details of the model, including changes made to the 
model to address concerns of the peer reviewers and commenters are 
included in Chapter 4 of the RIA. An example of the GEM input screen is 
shown in Figure II-4.
[GRAPHIC] [TIFF OMITTED] TR15SE11.004

    EPA and NHTSA have validated the GEM simulation of vocational 
vehicles against a commonly used simulation tool used in industry, GT-
Drive, for each vocational vehicle subcategory. Prior to using GT-Drive 
as a comparison tool, the agencies first benchmarked a GT-Drive 
simulation of the combination tractor tested at Southwest Research 
against the experimental test results from the chassis dynamometer in 
the same manner as done for GEM. Then the EPA developed three 
vocational vehicle models (LHD, MHD, and HHD) and simulated them using 
both GEM and GT-Drive. Overall, the GEM and GT-Drive predicted the fuel 
consumption and CO2 emissions for all three vocational 
vehicle subcategories with differences of less than 2 percent for the 
three test cycles--the California ARB Transient cycle, 55 mph cruise, 
and 65 mph cruise cycle.\150\ The final simulation model is described 
in greater detail in RIA Chapter 4 and is available for download by 
interested parties at (http://www.epa.gov/otaq/).
---------------------------------------------------------------------------

    \150\ See RIA Chapter 4, Table 4-8.
---------------------------------------------------------------------------

    The agencies are requiring that for demonstrating compliance, a 
chassis manufacturer would measure the performance of tires, input the 
values into GEM, and compare the model's output to the standard. As 
explained earlier, low rolling resistance tires are the only technology 
on which the agencies' own feasibility analysis for these vehicles is 
predicated. The input values for the simulation model will be derived 
by the manufacturer from the final tire test procedure described in 
this action. The remaining model inputs will be fixed values pre-
defined by the agencies. These are detailed in the RIA Chapter 4, 
including the engine fuel consumption map to be used in the simulation.
(b) Tire Rolling Resistance Assessment
    In terms of how tire rolling resistance would be measured, the 
agencies proposed to require that the tire rolling resistance input to 
the GEM be determined using ISO 28580:2009(E), Passenger car, truck and 
bus tyres--Methods of measuring rolling resistance--Single point test 
and correlation of measurement results.\151\ The agencies stated that 
they believed the ISO test method was the most appropriate for this 
program because the method is the same one used by the NHTSA tire fuel 
efficiency consumer information program,\152\ by European 
regulations,\153\ and by the EPA SmartWay program.
---------------------------------------------------------------------------

    \151\ See http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=44770.
    \152\ 75 FR 15893, March 30,2010.
    \153\ See http://www.energy.ca.gov/2009publications/CEC-600-2009-010/CEC-600-2009-010-SD-REV.PDF (last accessed May 9, 2011).
---------------------------------------------------------------------------

    The NPRM also discussed the potential for tire-to-tire variability 
to confound rolling resistance measurement results for LRR tires--that 
is, different tires of the same tire model could turn out to have 
different rolling resistance measurements when run on

[[Page 57183]]

the same test. NHTSA's research during the development of the light-
duty vehicle tire fuel efficiency consumer information program 
identified several sources of variability including test procedures, 
test equipment and the tires themselves, but found that all of the 
existing test methods had similar levels of and sources of 
variability.\154\ The agencies proposed to address production tire-to-
tire variability by specifying that three tire samples within each tire 
model be tested three times each, and that the average of the nine 
tests would be used as the Rolling Resistance Coefficient (CRR) for the 
tire, which would be the basis for the rolling resistance value for 
that tire that the manufacturer would enter into the GEM. The agencies 
requested comment on this proposed method.\155\
---------------------------------------------------------------------------

    \154\ 75 FR 15893, March 30, 2010.
    \155\ See generally 75 FR at 74204.
---------------------------------------------------------------------------

    The agencies received many comments on the subject of tire rolling 
resistance, including suggestions for alternative test procedures and 
compliance issues. Regarding whether the agencies should base tire CRR 
inputs for the GEM on the use of the ISO 28580 test procedure, the 
American Automotive Policy Council (AAPC) argued that the agencies 
should instead require the SAE J2452 Coastdown test method for 
calculating tire rolling resistance, which the commenter stated was 
preferred by OEMs because it simulates the use of tires on actual 
vehicles rather than the ISO procedure which tests the tire by itself. 
The Rubber Manufacturers Association (RMA) argued, in contrast, that 
the agencies should use the SAE J1269 multi-point test, which is 
currently the basis for the EPA SmartWay\TM\ CRR baseline values. RMA 
also argued that the SAE J1269 multi-point test can be used to 
accurately predict truck/bus tire CRR at various loads and inflations, 
including at the ISO 28580 load and inflation conditions, and that 
therefore the agencies should use the SAE test, or if the agencies want 
to use ISO, they should accept results from the SAE test and just 
correlate them. Regarding compliance obligations, RMA further argued 
that it was not clear how or in what format testing information would 
need to be provided in order to be in compliance with the proposed 
requirement at Sec.  1037.125(i).
    The agencies analyzed many comments on the subject of tire rolling 
resistance. One of the primary concerns raised in comments was that the 
proposed test protocol and measurement methodology would not adequately 
address production tire variability and measurement variability. 
Commenters stated that machine-to-machine differences are a significant 
source of variation, and this variation would make it difficult for 
manufacturers to be confident that the agency would assign the same CRR 
to a tire was tested for compliance purposes. Commenters argued that 
the ISO 28580 test method is unique in that it specifies a procedure to 
correlate results between different test equipment (i.e., different 
rolling resistance test machines), but not all aspects of the ISO 
procedure have been completely defined. Commenters stated that under 
ISO 28580, the lab alignment procedure depends on the specification of 
a reference test machine to which all other labs will align their 
measurement results. RMA particularly emphasized the need for 
establishing a tire testing reference lab for use with ISO 28580, 
referencing the European Tyre and Rim Technical Organization (ETRTO) 
estimate that CRR values could vary as much as 20 percent absent an 
inter-laboratory alignment procedure. RMA stated the agencies should 
specify a reference laboratory with the designation proposed in a 
supplemental notice that provides public comment. In addition, RMA 
commented that the extra burden proposed by the agencies for testing 
three tires, three times each is nine times more burdensome than what 
is required through the ISO procedure.
    Based on the additional tire rolling resistance research conducted 
by the agencies, we have decided to use the ISO 28580 test procedure, 
as proposed, to measure tire performance for these final rules.
    The agencies believe this test procedure provides two advantages 
over other test methods. First, the ISO 28580 test method is unique in 
that it specifies a procedure to correlate results between different 
test equipment (i.e., different tire rolling resistance test machines). 
This is important because NHTSA's research conducted for the light-duty 
tire fuel efficiency program indicated that machine-to-machine 
differences are a source of variation.\156\ In addition, the ISO 28580 
test procedure is either used, or proposed to be used, by several 
groups including the European Union through Regulation (EC) No 661/2009 
\157\and the California Air Resources Board (CARB) through a staff 
recommendation for a California regulation,\158\ and the EPA SmartWay 
program. Using the ISO 28580 may help reduce burden on manufacturers by 
allowing a single test protocol to be used for multiple regulations and 
programs. While we recognize that commenters recommended the use of 
other test procedures, like SAE J1269, the agencies have determined 
there is no established data conversion method from the SAE J1269 
vehicle condition for vocational vehicle tires to the ISO 28580 single 
point condition at this time, and that given our reasonable preference 
for the ISO procedure, it would not be practical to attempt to include 
the use of the SAE J1269 procedure as an optional way of determining 
CRR values for the GEM inputs.
---------------------------------------------------------------------------

    \156\ 75 FR 15893, March 30, 2010.
    \157\ See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2009:200:0001:0024:EN:PDF (last accessed May 
8, 2011).
    \158\ See http://www.energy.ca.gov/2009publications/CEC-600-2009-010/CEC-600-2009-010-SD-REV.PDF (last accessed May 9, 2011).
---------------------------------------------------------------------------

    The agencies received comments from the Rubber Manufacturers 
Association, Michelin, and Bridgestone which identified the need to 
develop a reference lab and alignment tires. Because the ISO has not 
yet specified a reference lab and machine for the ISO 28580 test 
procedure, NHTSA announced in its March 2010 final rule concerning the 
light-duty tire fuel efficiency consumer information program that NHTSA 
would specify this laboratory for the purposes of implementing that 
rule so that tire manufacturers would know the identity of the machine 
against which they may correlate their test results. NHTSA has not yet 
announced the reference test machine(s) for the tire fuel efficiency 
consumer information program. Therefore, for the light-duty tire fuel 
efficiency rule, the agencies are postponing the specification of a 
procedure for machine-to-machine alignment until a tire reference lab 
is established. The agencies anticipate establishing this lab in the 
future with intentions for the lab to accommodate the light-duty tire 
fuel efficiency program.
    Under the ISO 28580 lab alignment procedure, machine alignment is 
conducted using batches of alignment tires of two models with defined 
differences in rolling resistance that are certified on a reference 
test machine. ISO 28580 specifies requirements for these alignment 
tires (``Lab Alignment Tires'' or LATs), but exact tire sizes or models 
of LATs are not specifically identified in ISO 28580. Because the test 
procedure has not been finalized and heavy-duty LATs are not currently 
defined, the agencies are postponing the use of these elements of ISO 
28580 to

[[Page 57184]]

a future rulemaking. The agencies also note the lab-to-lab comparison 
conducted in the most recent EPA tire test program mentioned 
previously. The agencies reviewed the CRR data from the tires that were 
tested at both the STL and Smithers laboratories to assess inter-
laboratory and machine variability. The agencies conducted statistical 
analysis of the data to gain better understanding of lab-to-lab 
correlation and developed an adjustment factor for data measured at 
each of the test labs. Based on these results, the agencies believe the 
lab-to-lab variation for the STL and Smithers laboratories would have 
very small effect on measured CRR values. Based on the test data, the 
agencies judge that it is reasonable to implement the HD program with 
current levels of variability, and to allow the use of either Smithers 
or STL laboratories for determining the CRR value in the HD program, or 
demonstrate that the test facilities will not bias results low relative 
to Smithers or STL laboratories.
    RMA also commented that the extra burden proposed by the agencies 
for testing three tires, three times each is nine times more burdensome 
than what is required through the ISO procedure. Since the proposal, 
EPA obtained replicate test data for a number of Class 8 combination 
tractor tires from various manufacturers. Some of these were tires 
submitted to SmartWay for verification, while some were tires tested by 
manufacturers for other purposes. Three tire model samples for 11 tire 
models were tested using the ISO 28580 test.\159\ A mean and a standard 
deviation were calculated for each set of three replicate measurements 
performed on each tire of the 3-tire sample. The coefficient of 
variability (COV) of the CRR was calculated by dividing the standard 
deviation by the mean. The values of COV ranged from 0 percent (no 
measurable variability) to six percent. In addition, during the period 
September 2010 and June 2011, EPA contracted with Smithers-Rapra to 
select and test for rolling resistance using ISO 28580 for a 
representative sample of Class 4-8 vocational vehicle tires. As part of 
the test, 10 tires were selected for replicate testing.\160\ Three 
replicate tests were conducted for each of the tires, to evaluate test 
variability only. The COV of the RRC results ranged from 
nearly 0 to 2 percent, with a mean of less than 1 percent. Based on the 
results of these two testing programs, the agencies determined that the 
impact of production variability is greater than the impact of 
measurement variability. Thus, the agencies concluded that the extra 
burden of testing a single tire three times was not necessary to obtain 
accurate results, but the variability of RRC results due to 
manufacturing of the tires is significant to continue to require 
testing of three tire samples for each tire model. In summary, we are 
allowing manufacturers to determine the rolling resistance coefficient 
of the heavy-duty tires by testing three tire samples one time each.
---------------------------------------------------------------------------

    \159\ Bachman, Joseph. EPA Memorandum to the Docket. Heavy-Duty 
Tire Evaluation. Docket EPA-HQ-OAR-2010-0162. July 2011.
    \160\ Bachman, Joseph. EPA Memorandum to the Docket. Heavy-Duty 
Tire Evaluation. Docket EPA-HQ-OAR-2010-0162. July 2011.
---------------------------------------------------------------------------

    For the final rules, the agencies are also including a warm up 
cycle as part of the procedure for bias ply tires to allow these tires 
to reach a steady temperature and volume state before ISO 28580 
testing. This procedure is similar to a procedure that was developed 
for the light-duty tire fuel efficiency consumer information program, 
and was adopted from a procedure defined in Federal motor vehicle 
safety standard No. 109 (FMVSS No. 109).\161\
---------------------------------------------------------------------------

    \161\ See 49 CFR 571.109.
---------------------------------------------------------------------------

    Finally, the agencies are including testing and reporting for 
`single-wide' or `super-single' type tires. These tires replace the 
traditional `dual' wheel tire combination with a single wheel and tire 
that is nearly as wide as the dual combination with similar load 
capabilities. These tire types were developed as a fuel saving 
technology. The tires provide lower rolling resistance along with a 
reduction in weight when compared to a typical set of dual wheel tire 
combinations; and are one of the technologies included in the EPA 
SmartWay\TM\ program. The agencies have learned that there is limited 
testing equipment available that is capable of testing single wide 
tires; single wide tires require a wider test machine drum than 
required for conventional tires. Although the number of machines 
available is limited, the agencies believe the equipment is adequate 
for the testing and reporting of CRR for this program.
    As discussed above, the agencies are taking the approach of using 
CRR for the HD fuel efficiency and greenhouse gas program to align with 
the measurement methodology already employed or proposed by the EPA 
SmartWay program, the European Union Regulation (EC) No 661/2009 \162\ 
and the California Air Resources Board (CARB) through a staff 
recommendation for a California regulation.\163\ In the NPRM, the 
agencies proposed to use CRR, but for purposes of developing these 
final rules, the agencies also evaluated whether to use CRR or Rolling 
Resistance Force (RRF) as the measurement for tire rolling 
resistance for the GEM input. The agencies considered RRF 
largely because in the NPRM for Passenger Car Tire Fuel Efficiency 
(TFE) program, NHTSA had proposed to use RRF. A key 
distinction between these two programs, and their associated metrics, 
are the differences in how the measurement data are used and who uses 
the data. In particular, the HD fuel efficiency and GHG emissions 
program is a compliance program using information developed by and for 
technical personnel at manufacturers and agencies to determine a 
vehicle's compliance with regulations. The TFE program, in contrast, is 
a consumer education program intended to inform consumers making 
purchase decisions regarding the fuel saving benefits of replacement 
passenger car tires. The target audiences are much different for the 
two programs which in turn affect how the information will be used. The 
agencies believe that RRF may be more intuitive for non-
technical people because tires that are larger and/or that carry higher 
loads will generally have numerically higher RRF values than 
smaller tires and/or tires that carry lower loads. CRR values generally 
follow an opposite trend, where tires that are larger and/or carry 
higher loads will generally have numerically lower CRR values than 
smaller tires and/or tires that carry lower loads. The agencies believe 
this key distinction helps define the type of metrics to be used and 
communicated in accordance with their respective purposes.
---------------------------------------------------------------------------

    \162\ See Note 157, above.
    \163\ See Note 158, above.
---------------------------------------------------------------------------

    Additionally, the CRR metric for use in the MD/HD program is not 
susceptible to the skew associated with tire diameter. Medium- and 
heavy-duty vehicle tires are available in a small fraction of the tire 
sizes of the passenger market and, for the most part, are larger tires 
than those found on passenger cars. When viewing CRR over a larger 
range of sizes, small diameter tires tend to appear as having a lower 
performance, which is not necessarily accurate, with the converse 
occurring as the diameter increases.
    Using the CRR value for determining the rolling resistance also 
takes into account the load carrying capability for the tire being 
tested, which, intuitively, can lead to some potentially confusing 
results. Several vocational vehicle manufacturers argued in their 
comments that LRR tires were not available for, e.g., vehicles like 
refuse trucks, which tend to use large diameter tires to carry very 
heavy loads. Based on the agencies'

[[Page 57185]]

testing, in fact, the measured CRR (as opposed to the RRF) 
for refuse trucks were found to be among the best tested. This finding 
can be explained by considering that CRR is calculated by dividing the 
measured rolling resistance force by the tire's load capacity rating. 
Although the tire may have a relatively high rolling resistance force, 
the tire load capacity rating is also very high, resulting in an 
overall lower (better) CRR value than many other types of tires. The 
amount of load tire can carry (test load) contributes to a very low 
reported CRR, thus confirming low rolling resistance tires meeting the 
standards, as measured by CRR, are available to the industry regardless 
of segment or application.
    Based on these considerations, the agencies have decided to use the 
CRR metric for the HD fuel efficiency and GHG emissions program.
(c) Defined Vehicle Configurations in the GEM
    As discussed above, the agencies are finalizing a methodology that 
chassis manufacturers will use to quantify the tire rolling resistance 
values to be input into the GEM. Moreover, the agencies are defining 
the remaining GEM inputs (i.e., specifying them by rule), which differ 
by the regulatory subcategory (for reasons described in the RIA Chapter 
4). The defined inputs, among others, include the drive cycle, 
aerodynamics, vehicle curb weight, payload, engine characteristics, and 
drivetrain for each vehicle type.
(i) Metric
    Based on NAS's recommendation and feedback from the heavy-duty 
truck industry, NHTSA and EPA proposed standards for vocational 
vehicles that would be expressed in terms of moving a ton of payload 
over one mile. Thus, NHTSA's proposed fuel consumption standards for 
these vehicles would be represented as gallons of fuel used to move one 
ton of payload one thousand miles, or gal/1,000 ton-mile. EPA's 
proposed CO2 vehicle standards would be represented as grams 
of CO2 per ton-mile. The agencies received comments that a 
payload-based metric is not appropriate for all types of vocational 
vehicles, specifically buses. The agencies recognize that a payload-
based approach may not be the most representative of an individual 
vocational application; however, it best represents the broad 
vocational category. The metric which we proposed treats all vocational 
applications equally and requires the same technologies be applied to 
meet the standard. Thus, the agencies are adopting the proposed metric, 
but will revisit the issue of metrics in any future action, if 
required, depending on the breadth of each standard.
(ii) Drive cycle
    The drive cycles proposed for the vocational vehicles consisted of 
the same three modes used for the Class 7 and 8 combination tractors. 
The proposed cycle included the Transient mode, as defined by 
California ARB in the HHDDT cycle, a constant speed cycle at 65 mph and 
a 55 mph constant speed mode. The agencies proposed different 
weightings for each mode for vocational vehicles than those proposed 
for Class 7 and 8 combination tractors, given the known difference in 
driving patterns between these two categories of vehicles. The same 
reasoning underlies the agencies' use of the Heavy-duty FTP cycle to 
evaluate compliance with the standards for diesel engines used in 
vocational vehicles.
    The variety of vocational vehicle applications makes it challenging 
to establish a single cycle which is representative of all such trucks. 
However, in aggregate, the vocational vehicles typically operate over 
shorter distances and spend less time cruising at highway speeds than 
combination tractors. The agencies evaluated for proposal two sources 
for mode weightings, as detailed in RIA Chapter 3. The agencies 
proposed the mode weightings based on the vehicle speed characteristics 
of single unit trucks used in EPA's MOVES model which were developed 
using Federal Highway Administration data to distribute vehicle miles 
traveled by road type.\164\ The proposed weighted CO2 and 
fuel consumption value consisted of 37 percent of 65 mph Cruise, 21 
percent of 55 mph Cruise, and 42 percent of Transient performance.
---------------------------------------------------------------------------

    \164\ The Environmental Protection Agency. Draft MOVES2009 
Highway Vehicle Population and Activity Data. EPA-420-P-09-001, 
August 2009 http://www.epa.gov/otaq/models/moves/techdocs/420p09001.pdf.
---------------------------------------------------------------------------

    The agencies received comments stating that the proposed drive 
cycles and weightings are not representative of individual vocational 
applications, such as buses and refuse haulers. A number of groups 
commented that the vocational vehicle cycle is not representative of 
real world driving and recommended changes to address that concern. 
Several organizations proposed the addition of new drive cycles to make 
the test more representative.
    Bendix suggested using the Composite International Truck Local and 
Commuter Cycle (CILCC) as the general purpose mixed urban/freeway 
cycles and to use four representative cycles: mixed urban, freeway, 
city bus, refuse, and utility. Bendix suggested using the Standardized 
On-Road Test (SORT) cycles for vocational vehicles operating in the 
urban environment in addition to SORT cycles for 3 different 
vocations--with separate weightings. They stated that SORT with an 
average speed of 11.2 mph, lines up most closely with the average of 
transit bus duty cycles at 9.9 mph as well as the overall U.S. National 
average of 12.6 mph. As alternative approaches they suggested adopting 
the Orange County duty cycle for the urban transit bus vocation, or 
creating an Urban Transit Bus cycle with several possible weighting 
factors--all with very high percentage transient (90% to 100%), very 
low 55 mph (0% to 7%), very low 65 mph (0% to 3%), and an average speed 
of 15 to 17 mph. Bendix supported their assertions about urban bus 
vehicle speed with data from the 2010 American Public Transportation 
Association (APTA) `Fact Book' and other sources. In contrast, Bendix 
stated, the GEM cycle average speed is currently 32.6 mph. Such high 
speeds at steady state will penalize technologies such as 
hybridization.
    Clean Air Task Force said the agencies have not adequately 
addressed the diversity of the vocational vehicle fleet since they are 
not distinguished by different duty cycles. They urged the agencies to 
sub-divide vocational vehicles by expected use, with separate test 
cycles for each sub-group in order to capture the full potential 
benefits of hybridization and other advanced technologies in a 
meaningful and accurate way in future rulemakings for MY2019 and later 
trucks.
    Two groups cautioned that unintended consequences could result from 
the lack of diversity in duty cycles. DTNA said that the single drive 
cycle proposed for all vehicles by the agencies would likely lead to 
unintended consequences--such as customers being driven for regulatory 
reasons to purchase a transmission that does not suit their actual 
operation. Similarly, Volvo said medium- and heavy-duty vehicles are 
uniquely built for specific applications but it will not be feasible to 
develop regulatory protocols that can accurately predict efficiency in 
each application duty cycle. This trade-off could result in unintended 
or negative consequences in parts of the market.
    Several commenters suggested changing the weightings of the cycle 
to more accurately reflect real world driving. Allison stated that the 
vocational vehicle cycle includes too much steady state driving time. 
They suggested (with supporting data from

[[Page 57186]]

the Oakridge National Laboratory analysis) reducing steady state 
driving at 60 mph to minimal or no time on the cycle to address this 
problem. Allison commented that GEM contains lengthy accelerations to 
reach 55 and 65 miles per hour--much longer than is required in real 
world driving. They supported this statement with data from a testing 
program conducted at Oakridge National Laboratory showing medium- and 
heavy-duty vehicles accelerate more rapidly than in the GEM drive 
cycle. According to Allison, this long acceleration time in the GEM, 
coupled with too much steady state operation with very little 
variation, is not representative of vocational vehicle operation. In 
addition, Allison said that the GEM does not adequately account for 
shift time, clutch profile, turbo lag, and other impacts on both steady 
state and transient operation. The impact, they state, is that the 
cycle will hinder proper deployment of technologies to reduce fuel 
consumption and GHG emissions.
    BAE focused their comments on urban transit bus operation. They 
stated the weighting factors for steady state operation are 
inconsistent with urban transit bus cycles.
    Other commenters suggested the agencies develop chassis dynamometer 
tests based on the engine (FTP) test. Cummins said that chassis 
dynamometer testing should allow the use of average vehicle 
characteristics to determine road load and make use of the vehicle FTP 
and SET cycles. Others commented that the correlation between the FTP 
and the UDDS is poor.
    After careful consideration of the comments, the agencies are 
adopting the proposed drive cycles. The final drive cycles and 
weightings represent the straight truck operations which dominate the 
vehicle miles travelled by vocational vehicles. The agencies do not 
believe that application-specific drive cycles are required for this 
final action because the program is based on the generally-applicable 
use of low rolling resistance tires. The drive cycles that we are 
adopting treat all vocational applications equally predicate standard 
stringency on use of the same technology (LRR tires) to meet the 
standard. The drive cycles in the final rule accurately reflect the 
performance of this technology. The agencies are also finalizing, as 
proposed, the mode weightings based on the vehicle speed 
characteristics of single unit trucks used in EPA's MOVES model which 
were developed using Federal Highway Administration data to distribute 
vehicle miles traveled by road type.\165\ Similar to the issue of 
metrics discussed above, the agencies may revisit drive cycles and 
weightings in any future regulatory action to develop standards 
specific to applications.
---------------------------------------------------------------------------

    \165\ The Environmental Protection Agency. Draft MOVES2009 
Highway Vehicle Population and Activity Data. EPA-420-P-09-001, 
August 2009 http://www.epa.gov/otaq/models/moves/techdocs/420p09001.pdf.
---------------------------------------------------------------------------

(iii) Empty Weight and Payload
    The total weight of the vehicle is the sum of the tractor curb 
weight and the payload. The agencies are proposed to specify each of 
these aspects of the vehicle. The agencies developed the proposed 
vehicle curb weight inputs based on industry information developed by 
ICF.\166\ The proposed curb weights were 10,300 pounds for the LHD 
trucks, 13,950 pounds for the MHD trucks, and 29,000 pounds for the HHD 
trucks.
---------------------------------------------------------------------------

    \166\ ICF International. ``Investigation of Costs for Strategies 
to Reduce Greenhouse Gas Emissions for Heavy-Duty On-Road 
Vehicles.'' July 2010. Pages 16-20. Docket ID EPA-HQ-OAR-
2010-0162-0044.
---------------------------------------------------------------------------

    NHTSA and EPA proposed payload requirements for each regulatory 
category developed from Federal Highway statistics based on averaging 
the payloads for the weight categories represented within each vehicle 
subcategory.\167\ The proposed payloads were 5,700 pounds for the Light 
Heavy-Duty trucks, 11,200 pounds for Medium Heavy-Duty trucks, and 
38,000 pounds for Heavy Heavy-Duty trucks.
---------------------------------------------------------------------------

    \167\ The U.S. Federal Highway Administration. Development of 
Truck Payload Equivalent Factor. Table 11. Last viewed on March 9, 
2010 at http://ops.fhwa.dot.gov/freight/freight_analysis/faf/faf2_reports/reports9/s510_11_12_tables.htm.
---------------------------------------------------------------------------

    The agencies received comments from several stakeholders regarding 
the proposed curb weights and payloads for vocational vehicles. BAE 
said a Class 8 transit bus has a typical curb weight of 27,000 pounds 
and maximum payload of 15,000 pounds. Daimler commented that Class 8 
buses have a GVWR of 42,000 pounds. Autocar said that Class 8 refuse 
trucks typically have a curb weight of 31,000 to 33,000 pounds, typical 
average payload of 10,000 pounds, and typical maximum payload of 20,000 
pounds.
    Upon further consideration, the agencies are reducing the assigned 
weight of heavy heavy-duty vocational vehicles. While we still believe 
the proposed values are appropriate for some vocational vehicles, we 
reduced the total weight to bring it closer to some of the lighter 
vocational vehicles. The agencies are adopting final curb weights of 
10,300 pounds for the LHD trucks, 13,950 pounds for the MHD trucks, and 
27,000 pounds for the HHD trucks. The agencies are also adopting 
payloads of 5,700 pounds for the Light Heavy-Duty trucks, 11,200 pounds 
for Medium Heavy-Duty trucks, and 15,000 pounds for Heavy Heavy-Duty 
trucks. Additional information is available in RIA Chapter 3.
(iv) Engine
    As the agencies are finalizing separate engine and vehicle 
standards, the GEM will be used to assess the compliance of the chassis 
with the vehicle standard. To maintain the separate assessments, the 
agencies are adopting the proposed approach of using fixed values that 
are predefined by the agencies for the engine characteristics used in 
GEM, including the fuel consumption map which provides the fuel 
consumption at hundreds of engine speed and torque points. If the 
agencies did not standardize the fuel map, then a vehicle that uses an 
engine with emissions and fuel consumption better than the standards 
would require fewer vehicle reductions than those being finalized. As 
proposed, the agencies are using diesel engine characteristics in the 
GEM, as most representative of the largest fraction of engines in this 
market. The agencies did not receive any adverse comments to using this 
approach.
    The agencies are finalizing two distinct sets of fuel consumption 
maps for use in GEM. The first fuel consumption map would be used in 
GEM for the 2014 through 2016 model years and represent a diesel engine 
which meets the 2014 model year engine CO2 emissions 
standards. A second fuel consumption map would be used beginning in the 
2017 model year and represents a diesel engine which meets the 2017 
model year CO2 emissions and fuel consumption standards and 
accounts for the increased stringency in the final MY 2017 standard). 
The agencies have modified the 2017 MY heavy heavy-duty diesel fuel map 
used in the GEM for the final rulemaking to address comments received. 
Details regarding this change can be found in RIA Chapter 4.4.4. 
Effectively there is no change in stringency of the vocational vehicle 
standard (not including the engine) between the 2014 MY and 2017 MY 
standards for the full rulemaking period. These inputs are reasonable 
(indeed, seemingly necessitated) given the separate final regulatory 
requirement that vocational vehicle chassis manufacturers use only 
certified engines.

[[Page 57187]]

(v) Drivetrain
    The agencies' assessment of the current vehicle configuration 
process at the truck dealer's level is that the truck companies provide 
software tools to specify the proper drivetrain matched to the buyer's 
specific circumstances. These dealer tools allow a significant amount 
of customization for drive cycle and payload to provide the best 
specification for the customer. The agencies are not seeking to disrupt 
this process. Optimal drivetrain selection is dependent on the engine, 
drive cycle (including vehicle speed and road grade), and payload. Each 
combination of engine, drive cycle, and payload has a single optimal 
transmission and final drive ratio. The agencies are specifying the 
engine's fuel consumption map, drive cycle, and payload; therefore, it 
makes sense to specify the drivetrain that matches.
(d) Engine Metrics and Test Procedures
    EPA proposed that the GHG emission standards for heavy-duty engines 
under the CAA would be expressed as g/bhp-hr while NHTSA's proposed 
fuel consumption standards under EISA, in turn, be represented as gal/
100 bhp-hr. The NAS panel did not specifically discuss or recommend a 
metric to evaluate the fuel consumption of heavy-duty engines. However, 
as noted above they did recommend the use of a load-specific fuel 
consumption metric for the evaluation of vehicles.\168\ An analogous 
metric for engines is the amount of fuel consumed per unit of work. The 
g/bhp-hr metric is also consistent with EPA's current standards for 
non-GHG emissions for these engines. The agencies did not receive any 
adverse comments related to the metrics for HD engines; therefore, we 
are adopting the metrics as proposed.
---------------------------------------------------------------------------

    \168\ See NAS Report, Note 21, at page 39.
---------------------------------------------------------------------------

    With regard to GHG and fuel consumption control, the agencies 
believe it is appropriate to set standards based on a single test 
procedure, either the Heavy-duty FTP or SET, depending on the primary 
expected use of the engine. EPA's criteria pollutant standards for 
engines currently require that manufacturers demonstrate compliance 
over the transient Heavy-duty FTP cycle; over the steady-state SET 
procedure; and during not-to-exceed testing. EPA created this multi-
layered approach to criteria emissions control in response to engine 
designs that optimized operation for lowest fuel consumption at the 
expense of very high criteria emissions when operated off the 
regulatory cycle. EPA's use of multiple test procedures for criteria 
pollutants helps to ensure that manufacturers calibrate engine systems 
for compliance under all operating conditions. We are not concerned if 
manufacturers further calibrate these engines off cycle to give better 
in-use fuel consumption while maintaining compliance with the criteria 
emissions standards as such calibration is entirely consistent with the 
goals of our joint program. Further, we believe that setting standards 
based on both transient and steady-state operating conditions for all 
engines could lead to undesirable outcomes.
    It is critical to set standards based on the most representative 
test cycles in order for performance in-use to obtain the intended (and 
feasible) air quality and fuel consumption benefits. We are finalizing 
standards based on the composite Heavy-duty FTP cycle for engines used 
in vocational vehicles reflecting these vehicles' primary use in 
transient operating conditions typified by frequent accelerations and 
decelerations as well as some steady cruise conditions as represented 
on the Heavy-duty FTP. The primary reason the agencies are finalizing 
two separate diesel engine standards--one for diesel engines used in 
tractors and the other for diesel engines used in vocational vehicles--
is to encourage engine manufacturers to install engine technologies 
appropriate to the intended use of the engine with the vehicle. The 
current non-GHG emissions engine test procedures also require the 
development of regeneration emission rates and frequency factors to 
account for the emission changes during a regeneration event (40 CFR 
86.004-28). EPA and NHTSA proposed not to include these emissions from 
the calculation of the compliance levels over the defined test 
procedures. Cummins and Daimler supported and stated sufficient 
incentives already exist for manufacturers to limit regeneration 
frequency. Conversely, Volvo opposed the omission of IRAF requirements 
for CO2 emissions because emissions from regeneration can be 
a significant portion of the expected improvement and a significant 
variable between manufacturers
    For the proposal, we considered including regeneration in the 
estimate of fuel consumption and GHG emissions and decided not to do so 
for two reasons. First, EPA's existing criteria emission regulations 
already provide a strong motivation to engine manufacturers to reduce 
the frequency and duration of infrequent regeneration events. The very 
stringent 2010 NOX emission standards cannot be met by 
engine designs that lead to frequent and extend regeneration events. 
Hence, we believe engine manufacturers are already reducing 
regeneration emissions to the greatest degree possible. In addition to 
believing that regenerations are already controlled to the extent 
technologically possible, we believe that attempting to include 
regeneration emissions in the standard setting could lead to an 
inadvertently lax emissions standard. In order to include regeneration 
and set appropriate standards, EPA and NHTSA would have needed to 
project the regeneration frequency and duration of future engine 
designs in the time frame of this program. Such a projection would be 
inherently difficult to make and quite likely would underestimate the 
progress engine manufacturers will make in reducing infrequent 
regenerations. If we underestimated that progress, we would effectively 
be setting a more lax set of standards than otherwise would be 
expected. Hence in setting a standard including regeneration emissions 
we faced the real possibility that we would achieve less effective 
CO2 emissions control and fuel consumption reductions than 
we will achieve by not including regeneration emissions. Therefore, the 
agencies are finalizing an approach as proposed which does not include 
the regenerative emissions.
(e) Hybrid Powertrain Technology
    Although the final vocational vehicle standards are not premised on 
use of hybrid powertrains, certain vocational vehicle applications may 
be suitable candidates for use of hybrids due to the greater frequency 
of stop-and-go urban operation and their use of power take-off (PTO) 
systems. Examples are vocational vehicles used predominantly in stop-
start urban driving (e.g., delivery trucks). As an incentive, the 
agencies are finalizing to provide credits for the use of hybrid 
powertrain technology as described in Section IV. Under the advanced 
technology credit provisions, credits generated by use of hybrid 
powertrains could be used to meet any of the heavy-duty standards, and 
are not restricted to the averaging set generating the credit, unlike 
the other credit provisions in the final rules. The agencies are 
finalizing that any credits generated using such advanced technologies 
could be applied to any heavy-duty vehicle or engine, and not be 
limited to the averaging set generating the credit. Section IV below 
also details the final approach to account for the use of a hybrid 
powertrain when evaluating compliance with the vehicle standard. In 
general, manufacturers can derive the fuel consumption and 
CO2 emissions

[[Page 57188]]

reductions based on comparative test results using the final chassis 
testing procedures.
(3) Summary of Final Flexibility and Credit Provisions
    EPA and NHTSA are finalizing four flexibility provisions 
specifically for heavy-duty vocational vehicle and engine 
manufacturers, as discussed in Section IV below. These are an 
averaging, banking and trading program for emissions and fuel 
consumption credits, as well as provisions for early credits, advanced 
technology credits, and credits for innovative vehicle or engine 
technologies which are not included as inputs to the GEM or are not 
demonstrated on the engine FTP test cycle. With the exception of the 
advanced technology credits, credits generated under these provisions 
can only be used within the same averaging set which generated the 
credit (for example, credits generated by HHD vocational vehicles can 
only be used by HHD vehicles). EPA is also adopting a temporary 
provision whereby N2O emission credits can be used to comply 
with the CO2 emissions standard, as described in Section IV 
below.
(3) Deferral of Standards for Small Chassis Manufacturing Business and 
Small Business Engine Companies
    EPA and NHTSA are finalizing an approach to defer greenhouse gas 
emissions and fuel consumption standards from small vocational vehicle 
chassis manufacturers meeting the SBA size criteria of a small business 
as described in 13 CFR 121.201 (see 40 CFR 1036.150 and 1037.150). The 
agencies will instead consider appropriate GHG and fuel consumption 
standards for these entities as part of a future regulatory action. 
This includes both U.S.-based and foreign small volume heavy-duty truck 
and engine manufacturers.
    The agencies have identified ten chassis entities that appear to 
fit the SBA size criterion of a small business.\169\ The agencies 
estimate that these small entities comprise less than 0.5 percent of 
the total heavy-duty vocational vehicle market in the United States 
based on Polk Registration Data from 2003 through 2007,\170\ and 
therefore that the exemption will have a negligible impact on the GHG 
emissions and fuel consumption improvements from the final standards.
---------------------------------------------------------------------------

    \169\ The agencies have identified Lodal, Indiana Phoenix, 
Autocar LLC, HME, Giradin, Azure Dynamics, DesignLine International, 
Ebus, Krystal Koach, and Millenium Transit Services LLC as potential 
small business chassis manufacturers.
    \170\ M.J. Bradley. Heavy-duty Vehicle Market Analysis. May 
2009.
---------------------------------------------------------------------------

    EPA and NHTSA have also identified three engine manufacturing 
entities that appear to fit the SBA size criteria of a small business 
based on company information included in Hoover's.\171\ Based on 2008 
and 2009 model year engine certification data submitted to EPA for non-
GHG emissions standards, the agencies estimate that these small 
entities comprise less than 0.1 percent of the total heavy-duty engine 
sales in the United States. The final exemption from the standards 
established under this rulemaking would have a negligible impact on the 
GHG emissions and fuel consumption reductions otherwise due to the 
standards.
---------------------------------------------------------------------------

    \171\ The agencies have identified Baytech Corporation, Clean 
Fuels USA, and BAF Technologies, Inc. as three potential small 
businesses.
---------------------------------------------------------------------------

    To ensure that the agencies are aware of which companies would be 
exempt, we are finalizing as proposed to require that such entities 
submit a declaration to EPA and NHTSA containing a detailed written 
description of how that manufacturer qualifies as a small entity under 
the provisions of 13 CFR 121.201, as described in Section V below.

E. Other Standards

    In addition to finalizing CO2 emission standards for 
heavy-duty vehicles and engines, EPA is also finalizing separate 
standards for N2O and CH4 emissions.\172\ NHTSA 
is not finalizing comparable separate standards for these GHGs because 
they are not directly related to fuel consumption in the same way that 
CO2 is, and NHTSA's authority under EISA exclusively relates 
to fuel efficiency. N2O and CH4 are important 
GHGs that contribute to global warming, more so than CO2 for 
the same amount of emissions due to their high Global Warming Potential 
(GWP).\173\ EPA is finalizing N2O and CH4 
standards which apply to HD pickup trucks and vans as well as to all 
heavy-duty engines. EPA is not finalizing N2O and 
CH4 standards for the Class 7 and 8 tractor or Class 2b-8 
chassis manufacturers because these emissions would be controlled 
through the engine program.
---------------------------------------------------------------------------

    \172\ NHTSA's statutory responsibilities relating to reducing 
fuel consumption are directly related to reducing CO2 
emissions, but not to the control of other GHGs.
    \173\ The global warming potentials (GWP) used in this rule are 
consistent with the 2007 Intergovernmental Panel on Climate Change 
(IPCC) Fourth Assessment Report (AR4). At this time, the 1996 IPCC 
Second Assessment Report (SAR) GWP values are used in the official 
U.S. greenhouse gas inventory submission to the United Nations 
Framework Convention on Climate Change (per the reporting 
requirements under that international convention). N2O 
has a GWP of 298 and CH4 has a GWP of 25 according to the 
2007 IPCC AR4.
---------------------------------------------------------------------------

    EPA requested comment on possible alternative CO2 
equivalent approaches to provide near-term flexibility for 2012-14 MY 
light-duty vehicles. As described below, EPA is finalizing alternative 
provisions allowing manufacturers to use CO2 credits, on a 
CO2-equivalent (CO2eq) basis, to meet the 
N2O and CH4 standards, which is consistent with 
many commenters' preferred approach.
    Almost universally across current engine designs, both gasoline- 
and diesel-fueled, N2O and CH4 emissions are 
relatively low today and EPA does not believe it would be appropriate 
or feasible to require reductions from the levels of current gasoline 
and diesel engines. This is because for the most part, the same 
hardware and controls used by heavy-duty engines and vehicles that have 
been optimized for non-methane hydrocarbon (NMHC) and NOX 
control indirectly result in highly effective control of N2O 
and CH4. Additionally, unlike criteria pollutants, specific 
technologies beyond those presently implemented in heavy-duty vehicles 
to meet existing emission requirements have not surfaced that 
specifically target reductions in N2O or CH4. 
Because of this, reductions in N2O or CH4 beyond 
current levels in most heavy-duty applications would occur through the 
same mechanisms that result in NMHC and NOX reductions and 
would likely result in an increase in the overall stringency of the 
criteria pollutant emission standards. Nevertheless, it is important 
that future engine technologies or fuels not currently researched do 
not result in increases in these emissions, and this is the intent of 
the final ``cap'' standards. The final standards would primarily 
function to cap emissions at today's levels to ensure that 
manufacturers maintain effective N2O and CH4 
emissions controls currently used should they choose a different 
technology path from what is currently used to control NMHC and 
NOX but also largely successful methods for controlling 
N2O and CH4. As discussed below, some 
technologies that manufacturers may adopt for reasons other than 
reducing fuel consumption or GHG emissions could increase 
N2O and CH4 emissions if manufacturers do not 
address these emissions in their overall engine and aftertreatment 
design and development plans. Manufacturers will be able to design and 
develop the engines and aftertreatment to avoid such emissions 
increases through appropriate emission control technology selections 
like those already used and available

[[Page 57189]]

today. Because EPA believes that these standards can be capped at the 
same level, regardless of type of HD engine involved, the following 
discussion relates to all types of HD engines regardless of the 
vehicles in which such engines are ultimately used. In addition, since 
these standards are designed to cap current emissions, EPA is 
finalizing the same standards for all of the model years to which the 
rules apply.
    EPA believes that the final N2O and CH4 cap 
standards will accomplish the primary goal of deterring increases in 
these emissions as engine and aftertreatment technologies evolve 
because manufacturers will continue to target current or lower 
N2O and CH4 levels in order to maintain typical 
compliance margins. While the cap standards are set at levels that are 
higher than current average emission levels, the control technologies 
used today are highly effective and there is no reason to believe that 
emissions will slip to levels close to the cap, particularly 
considering compliance margin targets. The caps will protect against 
significant increases in emissions due to new or poorly implemented 
technologies. However, we also believe that an alternative compliance 
approach that allows manufacturers to convert these emissions to 
CO2eq emission values and combine them with CO2 
into a single compliance value would also be appropriate, so long as it 
did not undermine the stringency of the CO2 standard. As 
described below, EPA is finalizing that such an alternative compliance 
approach be available to manufacturers to provide certain flexibilities 
for different technologies.
    EPA requested comments in the NPRM on the approach to regulating 
N2O and CH4 emissions including the 
appropriateness of ``cap'' standards, the technical bases for the 
levels of the final N2O and CH4 standards, the 
final test procedures, and the final timing for the standards. In 
addition, EPA requested any additional emissions data on N2O 
and CH4 from current technology engines. We solicited 
additional data, and especially data for in-use vehicles and engines 
that would help to better characterize changes in emissions of these 
pollutants throughout their useful lives, for both gasoline and diesel 
applications. As is typical for EPA emissions standards, we are 
finalizing that manufacturers should establish deterioration factors to 
ensure compliance throughout the useful life. We are not at this time 
aware of deterioration mechanisms for N2O and CH4 
that would result in large deterioration factors, but neither do we 
believe enough is known about these mechanisms to justify finalizing 
assigned factors corresponding to no deterioration, as we are 
finalizing for CO2, or for that matter to any predetermined 
level. In addition to N2O and CH4 standards, this 
section also discusses air conditioning-related provisions and EPA 
provisions to extend certification requirements to all-electric HD 
vehicles and vehicles and engines designed to run on ethanol fuel.
(1) What is EPA's Approach to Controlling N2O?
    N2O is a global warming gas with a GWP of 298. It 
accounts for about 0.3 percent of the current greenhouse gas emissions 
from heavy-duty trucks.\174\
---------------------------------------------------------------------------

    \174\ Value adapted from ``Inventory of U.S. Greenhouse Gas 
Emissions and Sinks: 1990-2007''. April 2009.
---------------------------------------------------------------------------

    N2O is emitted from gasoline and diesel vehicles mainly 
during specific catalyst temperature conditions conducive to 
N2O formation. Specifically, N2O can be generated 
during periods of emission hardware warm-up when rising catalyst 
temperatures pass through the temperature window when N2O 
formation potential is possible. For current heavy-duty gasoline 
engines with conventional three-way catalyst technology, N2O 
is not generally produced in significant amounts because the time the 
catalyst spends at the critical temperatures during warm-up is short. 
This is largely due to the need to quickly reach the higher 
temperatures necessary for high catalyst efficiency to achieve emission 
compliance of criteria pollutants. N2O formation is 
generally only a concern with diesel and potentially with future 
gasoline lean-burn engines with compromised NOX emissions 
control systems. If the risk for N2O formation is not 
factored into the design of the controls, these systems can but need 
not be designed in a way that emphasizes efficient NOX 
control while allowing the formation of significant quantities of 
N2O. However, these future advanced gasoline and diesel 
technologies do not inherently require N2O formation to 
properly control NOX. Pathways exist today that meet 
criteria emission standards that would not compromise N2O 
emissions in future systems as observed in current production engine 
and vehicle testing \175\ which would also work for future diesel and 
gasoline technologies. Manufacturers would need to use appropriate 
technologies and temperature controls during future development 
programs with the objective to optimize for both NOX and 
N2O control. Therefore, future designs and controls at 
reducing criteria emissions would need to take into account the balance 
of reducing these emissions with the different control approaches while 
also preventing inadvertent N2O formation, much like the 
path taken in current heavy-duty compliant engines and vehicles. 
Alternatively, manufacturers who find technologies that reduce criteria 
or CO2 emissions but see increases N2O emissions 
beyond the cap could choose to offset N2O emissions with 
reduction in CO2 as allowed in the CO2eq option 
discussed in Section II.E.3.
---------------------------------------------------------------------------

    \175\ Memorandum ``N2O Data from EPA Heavy-Duty 
Testing''.
---------------------------------------------------------------------------

    EPA is finalizing an N2O emission standard that we 
believe would be met by most current-technology gasoline and diesel 
vehicles at essentially no cost to the vehicle, though the agency is 
accounting for additional N2O measurement equipment costs. 
EPA believes that heavy-duty emission standards since 2008 model year, 
specifically the very stringent NOX standards for both 
engine and chassis certified engines, directly result in stringent 
N2O control. It is believed that the current emission 
control technologies used to meet the stringent NOX 
standards achieve the maximum feasible reductions and that no 
additional technologies are recognized that would result in additional 
N2O reductions. As noted, N2O formation in 
current catalyst systems occurs, but their emission levels are 
inherently low, because the time the catalyst spends at the critical 
temperatures during warm-up when N2O can form is short. At 
the same time, we believe that the standard would ensure that the 
design of advanced NOX control systems for future diesel and 
lean-burn gasoline vehicles would control N2O emission 
levels. While current NOX control approaches used on current 
heavy-duty diesel vehicles do not compromise N2O emissions 
and actually result in N2O control, we believe that the 
standards would discourage any new emission control designs for diesels 
or lean-burn gasoline vehicles that achieve criteria emissions 
compliance at the cost of increased N2O emissions. Thus, the 
standard would cap N2O emission levels, with the expectation 
that current gasoline and diesel vehicle control approaches that comply 
with heavy-duty vehicle emission standards for NOX would not 
increase their emission levels, and that the cap would ensure that 
future diesel and lean-burn gasoline vehicles with advanced 
NOX controls would appropriately control their emissions of 
N2O.

[[Page 57190]]

(a) Heavy-Duty Pickup Truck and Van N2O Exhaust Emission 
Standard
    EPA is finalizing the proposed per-vehicle N2O emission 
standard of 0.05 g/mi, measured over the Light-duty FTP and HFET drive 
cycles. Similar to the CO2 standard approach, the 
N2O emission level of a vehicle would be a composite of the 
Light-duty FTP and HFET cycles with the same 55 percent city weighting 
and 45 percent highway weighting. The standard would become effective 
in model year 2014 for all HD pickups and vans that are subject to the 
CO2 emission requirements. Averaging between vehicles would 
not be allowed. The standard is designed to prevent increases in 
N2O emissions from current levels, i.e., a no-backsliding 
standard.
    The N2O standard level is approximately two times the 
average N2O level of current gasoline and diesel heavy-duty 
trucks that meet the NOX standards effective since 2008 
model year.\176\ Manufacturers typically use design targets for 
NOX emission levels at approximately 50 percent of the 
standard, to account for in-use emissions deterioration and normal 
testing and production variability, and we expect manufacturers to 
utilize a similar approach for N2O emission compliance. We 
are not adopting a more stringent standard for current gasoline and 
diesel vehicles because the stringent heavy-duty NOX 
standards already result in significant N2O control, and we 
do not expect current N2O levels to rise for these vehicles 
particularly with expected manufacturer compliance margins.
---------------------------------------------------------------------------

    \176\ Memorandum ``N2O Data from EPA Heavy-Duty 
Testing.''
---------------------------------------------------------------------------

    Diesel heavy-duty pickup trucks and vans with advanced emission 
control technology are in the early stages of development and 
commercialization. As this segment of the vehicle market develops, the 
final N2O standard would require manufacturers to 
incorporate control strategies that minimize N2O formation. 
Available approaches include using electronic controls to limit 
catalyst conditions that might favor N2O formation and 
considering different catalyst formulations. While some of these 
approaches may have associated costs, EPA believes that they will be 
small compared to the overall costs of the advanced NOX 
control technologies already required to meet heavy-duty standards.
    The light-duty GHG rule requires that manufacturers begin testing 
for N2O by 2015 model year. The manufacturers of complete 
pickup trucks and vans (Ford, General Motors, and Chrysler) are already 
impacted by the light-duty GHG rule and will therefore have this 
equipment and capability in place for the timing of this rulemaking.
    Overall, we believe that manufacturers of HD pickups and vans (both 
gasoline and diesel) would meet the standard without implementing any 
significantly new technologies, only further refinement of their 
existing controls, and we do not expect there to be any significant 
costs associated with this standard.
(b) Heavy-Duty Engine N2O Exhaust Emission Standard
    EPA proposed a per engine N2O emissions standard of 0.05 
g/bhp-hr for heavy-duty engines, but is finalizing a standard of 0.10 
g/bhp-hr based on additional data submitted to the agency which better 
represents the full range of current diesel and gasoline engine 
performance. The final N2O standard becomes effective in 
2014 model year for diesel engines, as proposed. However, EPA is 
finalizing N2O standards for gasoline engines that become 
effective in 2016 model year to align with the first year of the 
CO2 gasoline engine standards. Without this alignment, 
manufacturers would not have any flexibility, such as CO2eq 
credits, in meeting the N20 cap and therefore would not have 
any recourse to comply if an engine's N2O emissions were 
above the standard. The standard remains the same over the useful life 
of the engine. The N2O emissions would be measured over the 
composite Heavy-duty FTP cycle because it is believed that this cycle 
poses the highest risk for N2O formation versus the 
additional heavy-duty compliance cycles. The agencies received comments 
from industry suggesting that the N2O and CH4 
emissions be evaluated over the same test cycle required for 
CO2 emissions compliance. In other words, the commenters 
wanted to have the N2O emissions measured over the SET for 
engines installed in tractors. The agencies are not adopting this 
approach for the final action because we do not have sufficient data to 
set the appropriate N2O level using the SET. The agencies 
are not requiring any additional burden by requiring the measurement to 
be conducted over the Heavy-Duty FTP cycle because it is already 
required for criteria emissions. Averaging of N2O emissions 
between HD engines will not be allowed. The standard is designed to 
prevent increases in N2O emissions from current levels, 
i.e., a no-backsliding standard.
    The proposed N2O level was twice the average 
N2O level of primarily pre-2010 model year diesel engines as 
demonstrated in the ACES Study and in EPA's testing of two additional 
engines with selective catalytic reduction aftertreatement 
systems.\177\ Manufacturers typically use design targets for 
NOX emission levels of about 50 percent of the standard, to 
account for in-use emissions deterioration and normal testing and 
production variability, and manufacturers are expected to utilize a 
similar approach for N2O emission compliance.
---------------------------------------------------------------------------

    \177\ Coordinating Research Council Report: ACES Phase 1 of the 
Advanced Collaborative Emissions Study, 2009. (This study included 
detailed chemical characterization of exhaust species emitted from 
four 2007 model year heavy heavy diesel engines).
---------------------------------------------------------------------------

    EPA sought comment about deterioration factors for N2O 
emissions. See 75 FR 74208. Industry stakeholders recommended that the 
agency define a DF of zero. While we believe it is also possible that 
N2O emissions will not deteriorate in use, very little data 
exist for aged engines and vehicles. Therefore, the value we are 
assigning is conservative, specifically additive DF of 0.02 g/bhp-hr. 
While the value is conservative, it is small enough to allow compliance 
for all engines except those very close to the standards. For engines 
too close to the standard to use the assigned DFs, the manufacturers 
would need to demonstrate via engineering analysis that deterioration 
is less than assigned DF.
    EPA sought additional data on the level of the proposed 
N2O level of 0.05 g/bhp-hr. See 75 FR 74208. The agency 
received additional data of 2010 model year engines from the Engine 
Manufacturers Association.\178\ The agencies reanalyzed a new data set, 
as shown in Table II-22, to derive the final N2O standard of 
0.10 g/bhp-hr with a defined deterioration factor of 0.02 g/bhp-hr.
---------------------------------------------------------------------------

    \178\ Engine Manufacturers Association. EMA N2O Email 
03--22--2011. See Docket EPA-HQ-OAR-2010-0162.

[[Page 57191]]

                     Table II-22--N2O Data Analysis
------------------------------------------------------------------------
                                                           Composite FTP
                                            Rated power      cycle N2O
              Engine family                    (HP)       result  (g/bhp-
                                                                hr)
------------------------------------------------------------------------
EPA Data of 2007 Engine with SCR........  ..............           0.042
EPA Data of 2010 Production Intent        ..............           0.037
 Engine.................................
A.......................................             450          0.0181
A.......................................             600          0.0151
B.......................................             360          0.0326
C.......................................             380          0.0353
D.......................................             560          0.0433
D.......................................             455          0.0524
E.......................................             600          0.0437
F.......................................             500          0.0782
G.......................................             483          0.1127
H.......................................             385          0.0444
H.......................................             385          0.0301
H.......................................             385          0.0283
J.......................................             380          0.0317
========================================================================
                                                    Mean           0.043
                                                2 * Mean            0.09
------------------------------------------------------------------------

    Engine emissions regulations do not currently require testing for 
N2O. The Mandatory GHG Reporting final rule requires 
reporting of N2O and requires that manufacturers either 
measure N2O or use a compliance statement based on good 
engineering judgment in lieu of direct N2O measurement (74 
FR 56260, October 30, 2009). The light-duty GHG final rule allows 
manufacturers to provide a compliance statement based on good 
engineering judgment through the 2014 model year, but requires 
measurement beginning in 2015 model year (75 FR 25324, May 7, 2010). 
EPA is finalizing a consistent approach for heavy-duty engine 
manufacturers which allows them to delay direct measurement of 
N2O until the 2015 model year.
    Manufacturers without the capability to measure N2O by 
the 2015 model year would need to acquire and install appropriate 
measurement equipment in response to this final program. EPA has 
established four separate N2O measurement methods, all of 
which are commercially available today. EPA expects that most 
manufacturers would use either photo-acoustic measurement equipment for 
stand-alone, existing FTIR instrumentation at a cost of $50,000 per 
unit or upgrade existing emission measurement systems with NDIR 
analyzers for $25,000 per test cell.
    Overall, EPA believes that manufacturers of heavy-duty engines, 
both gasoline and diesel, would meet the final standard without 
implementing any new technologies, and beyond relatively small 
facilities costs for any company that still needs to acquire and 
install N2O measurement equipment, EPA does not project that 
manufacturers would incur significant costs associated with this final 
N2O standard.
    EPA is not adopting any vehicle-level N2O standards for 
heavy-duty vocational vehicles and combination tractors. The 
N2O emissions would be controlled through the heavy-duty 
engine portion of the program. The only requirement of those vehicle 
manufacturers to comply with the N2O requirements is to 
install a certified engine.
(2) What is EPA's approach to controlling CH4?
    CH4 is greenhouse gas with a GWP of 25. It accounts for 
about 0.03 percent of the greenhouse gases from heavy-duty trucks.\179\
---------------------------------------------------------------------------

    \179\ Value adapted from ``Inventory of U.S. Greenhouse Gas 
Emissions and Sinks: 1990-2007. April 2009.
---------------------------------------------------------------------------

    EPA is finalizing a standard that would cap CH4 emission 
levels, with the expectation that current heavy-duty vehicles and 
engines meeting the heavy-duty emission standards would not increase 
their levels as explained earlier due to robust current controls and 
manufacturer compliance margin targets. It would ensure that emissions 
would be addressed if in the future there are increases in the use of 
natural gas or any other alternative fuel. EPA believes that current 
heavy-duty emission standards, specifically the NMHC standards for both 
engine and chassis certified engines directly result in stringent 
CH4 control. It is believed that the current emission 
control technologies used to meet the stringent NMHC standards achieve 
the maximum feasible reductions and that no additional technologies are 
recognized that would result in additional CH4 reductions. 
The level of the standard would generally be achievable through normal 
emission control methods already required to meet heavy-duty emission 
standards for hydrocarbons and EPA is therefore not attributing any 
cost to this part of the final action. Since CH4 is produced 
in gasoline and diesel engines similar to other hydrocarbon components, 
controls targeted at reducing overall NMHC levels generally also work 
at reducing CH4 emissions. Therefore, for gasoline and 
diesel vehicles, the heavy-duty hydrocarbon standards will generally 
prevent increases in CH4 emissions levels. CH4 
from heavy-duty vehicles is relatively low compared to other GHGs 
largely due to the high effectiveness of the current heavy-duty 
standards in controlling overall HC emissions.
    EPA believes that this level for the standard would be met by 
current gasoline and diesel trucks and vans, and would prevent 
increases in future CH4 emissions in the event that 
alternative fueled vehicles with high methane emissions, like some past 
dedicated compressed natural gas vehicles, become a significant part of 
the vehicle fleet. Currently EPA does not have separate CH4 
standards because, unlike other hydrocarbons, CH4 does not 
contribute significantly to ozone formation.\180\ However, 
CH4 emissions levels in the gasoline and diesel heavy-duty 
truck fleet have nevertheless

[[Page 57192]]

generally been controlled by the heavy-duty HC emission standards. Even 
so, without an emission standard for CH4, future emission 
levels of CH4 cannot be guaranteed to remain at current 
levels as vehicle technologies and fuels evolve.
---------------------------------------------------------------------------

    \180\ But See Ford Motor Co. v. EPA, 604 F. 2d 685 (DC Cir. 
1979) (permissible for EPA to regulate CH4 under CAA 
section 202(b)).
---------------------------------------------------------------------------

    In recent model years, a small number of heavy-duty trucks and 
engines were sold that were designed for dedicated use of natural gas. 
While emission control designs on these recent dedicated natural gas-
fueled vehicles demonstrate CH4 control can be as effective 
as on gasoline or diesel equivalent vehicles, natural gas-fueled 
vehicles have historically generated significantly higher 
CH4 emissions than gasoline or diesel vehicles. This is 
because the fuel is predominantly methane, and most of the unburned 
fuel that escapes combustion without being oxidized by the catalyst is 
emitted as methane. However, even if these vehicles meet the heavy-duty 
hydrocarbon standard and appear to have effective CH4 
control by nature of the hydrocarbon controls, the heavy-duty standards 
do not require CH4 control and therefore some natural gas 
vehicle manufacturers have invested very little effort into methane 
control. While the final CH4 cap standard should not require 
any different emission control designs beyond what is already required 
to meet heavy-duty hydrocarbon standards on a dedicated natural gas 
vehicle (i.e., feedback controlled 3-way catalyst), the cap will ensure 
that systems provide robust control of methane much like a gasoline-
fueled engine. We are not finalizing more stringent CH4 
standards because we believe that the controls used to meet current 
heavy-duty hydrocarbon standards should result in effective 
CH4 control when properly implemented. Since CH4 
is already measured under the current heavy-duty emissions regulations 
(so that it may be subtracted to calculate NMHC), the final standard 
will not result in additional testing costs.
(a) Heavy-Duty Pickup Truck and Van CH4 Standard
    EPA is finalizing the proposed CH4 emission standard of 
0.05 g/mi as measured on the Light-duty FTP and HFET drive cycles, to 
apply beginning with model year 2014 for HD pickups and vans subject to 
the CO2 standards. Similar to the CO2 standard 
approach, the CH4 emission level of a vehicle will be a 
composite of the Light-duty FTP and HFET cycles, with the same 55 
percent city weighting and 45 percent highway weighting.
    The level of the standard is approximately two times the average 
heavy-duty gasoline and diesel truck and van levels.\181\ As with 
N2O, this standard level recognizes that manufacturers 
typically set emissions design targets with a compliance margin of 
approximately 50 percent of the standard. Thus, we believe that the 
standard should be met by current gasoline vehicles with no increase 
from today's CH4 levels. Similarly, since current diesel 
vehicles generally have even lower CH4 emissions than 
gasoline vehicles, we believe that diesels will also meet the standard 
with a larger compliance margin resulting in no change in today's 
CH4 levels.
---------------------------------------------------------------------------

    \181\ Memorandum ``CH4 Data from 2010 and 2011 Heavy-
Duty Vehicle Certification Tests''.
---------------------------------------------------------------------------

(b) Heavy-Duty Engine CH4 Exhaust Emission Standard
    EPA is adopting a heavy-duty engine CH4 emission 
standard of 0.10 g/hp-hr with a defined deterioration factor of 0.02 g/
bhp-hr as measured on the composite Heavy-duty FTP, to apply beginning 
in model year 2014 for diesel engines and in 2016 model year for 
gasoline engines. EPA is adopting a different CH4 standard 
than proposed based on additional data submitted to the agency which 
better represents the full range of current diesel and gasoline engine 
performance. EPA is adopting CH4 standards for gasoline 
engines that become effective in 2016 model year to align with the 
first year of the gasoline engine CO2 standards. Without 
this alignment, manufacturers would not have any flexibility, such as 
CO2eq credits, in meeting the CH4 cap and 
therefore would not be able to sell any engine with a CH4 
level above the standard. The final standard would cap CH4 
emissions at a level currently achieved by diesel and gasoline heavy-
duty engines. The level of the standard would generally be achievable 
through normal emission control methods already required to meet 2007 
emission standards for NMHC and EPA is therefore not attributing any 
cost to this part of this program (see 40 CFR 86.007-11).
    The level of the final CH4 standard is twice the average 
CH4 emissions from gasoline engines from General Motors in 
addition to the four diesel engines in the ACES study.\182\ As with 
N2O, this final level recognizes that manufacturers 
typically set emission design targets at about 50 percent of the 
standard. Thus, EPA believes the final standard would be met by current 
diesel and gasoline engines with little if any technological 
improvements. The agency believes a more stringent CH4 
standard is not necessary due to effective CH4 controls in 
current heavy-duty technologies, since, as discussed above for 
N2O, EPA believes that the challenge of complying with the 
CO2 standards should be the primary focus of the 
manufacturers.
---------------------------------------------------------------------------

    \182\ Coordinating Research Council Report: ACES Phase 1 of the 
Advanced Collaborative Emissions Study, 2009.
---------------------------------------------------------------------------

    CH4 is measured under the current 2007 regulations so 
that it may be subtracted to calculate NMHC. Therefore EPA expects that 
the final standard would not result in additional testing costs.
    EPA is not adopting any vehicle-level CH4 standards for 
heavy-duty combination tractors or vocational vehicles in this final 
action. The CH4 emissions will be controlled through the 
heavy-duty engine portion of the program. The only requirement of these 
truck manufacturers to comply with the CH4 requirements is 
to install a certified engine.
(3) Use of CO2 Credits
    As proposed, if a manufacturer is unable to meet the N2O 
or CH4 cap standards, the EPA program will allow the 
manufacturer to comply using CO2 credits. In other words, a 
manufacturer could offset any N2O or CH4 
emissions above the standard by taking steps to further reduce 
CO2. A manufacturer choosing this option would convert its 
measured N2O and CH4 test results that are in 
excess of the applicable standards into CO2eq to determine 
the amount of CO2 credits required. For example, a 
manufacturer would use 25 Mg of positive CO2 credits to 
offset 1 Mg of negative CH4 credits or use 298 Mg of 
positive CO2 credits to offset 1 Mg of negative 
N2O credits.\183\ By using the Global Warming Potential of 
N2O and CH4, the approach recognizes the inter-
correlation of these compounds in impacting global warming and is 
environmentally neutral for demonstrating compliance with the 
individual emissions caps. Because fuel conversion manufacturers 
certifying under 40 CFR part 85, subpart F do not participate in ABT 
programs, EPA is finalizing a compliance option for fuel conversion 
manufacturers to comply with the N2O and CH4 
standards that is similar to the credit program just described above. 
The compliance option will allow conversion manufacturers, on an 
individual engine family basis, to convert CO2 
overcompliance into CO2 equivalents of N20 and/or 
CH4 that can be subtracted from the CH4 and 
N20 measured values to demonstrate compliance with 
CH4 and/or N20 standards. Other than in the 
limited

[[Page 57193]]

case of N2O for model years 2014-16, we have not finalized 
similar provisions allowing overcompliance with the N2O or 
CH4 standards to serve as a means to generate CO2 
credits because the CH4 and N2O standards are cap 
standards representing levels that all but the worst vehicles should 
already be well below. Allowing credit generation against such cap 
standard would provide a windfall credit without any true GHG 
reduction.
---------------------------------------------------------------------------

    \183\ N2O has a GWP of 298 and CH4 has a 
GWP of 25 according to the IPCC AR4.
---------------------------------------------------------------------------

    The final NHTSA fuel consumption program will not use 
CO2eq, as suggested above. Measured performance to the NHTSA 
fuel consumption standards will be based on the measurement of 
CO2 with no adjustment for N2O and/or 
CH4. For manufacturers that use the EPA alternative 
CO2eq credit, compliance to the EPA CO2 standard 
will not be directly equivalent to compliance with the NHTSA fuel 
consumption standard.
(4) Amendment to Light-Duty Vehicle N2O and CH4 
Standards
    EPA also requested comment on revising a portion of the light-duty 
vehicle standards for N2O and CH4. 75 FR at 
74211. Specifically, EPA requested comments on two additional options 
for manufacturers to comply with N2O and CH4 
standards to provide additional near-term flexibility. EPA is 
finalizing one of those options, as discussed below.
    For light-duty vehicles, as part of the MY 2012-2016 rulemaking, 
EPA finalized standards for N2O and CH4 which 
take effect with MY 2012. 75 FR at 25421-24. Similar to the heavy-duty 
standards discussed in Section II.E above, the light-duty vehicle 
standards for N2O and CH4 were established to cap 
emissions and to prevent future emissions increases, and were generally 
not expected to result in the application of new technologies or 
significant costs for the manufacturers for current vehicle designs. 
EPA also finalized an alternative CO2 equivalent standard 
option, which manufacturers may choose to use in lieu of complying with 
the N2O and CH4 cap standards. The CO2 
equivalent standard option allows manufacturers to fold all 
N2O and CH4 emissions, on a CO2eq 
basis, along with CO2 into their otherwise applicable 
CO2 emissions standard level. For flexible fueled vehicles, 
the N2O and CH4 standards must be met on both 
fuels (e.g., both gasoline and E-85).
    After the light-duty standards were finalized, manufacturers raised 
concerns that for a few of the vehicle models in their existing fleet 
they were having difficulty meeting the N2O and/or 
CH4 standards, especially in the early years of the program 
for a few of the vehicle models in their existing fleet. These 
standards could be problematic in the near term because there is little 
lead time to implement unplanned redesigns of vehicles to meet the 
standards. In such cases, manufacturers may need to either drop vehicle 
models from their fleet or to comply using the CO2 
equivalent alternative. On a CO2eq basis, folding in all 
N2O and CH4 emissions would add 3-4 g/mile or 
more to a manufacturer's overall fleet-average CO2 emissions 
level because the alternative standard must be used for the entire 
fleet, not just for the problem vehicles.\184\ See 75 FR at 74211. This 
could be especially challenging in the early years of the program for 
manufacturers with little compliance margin because there is very 
limited lead time to develop strategies to address these additional 
emissions. As stated at proposal, EPA believed this posed a legitimate 
issue of sufficiency of lead time in the short term, as well as an 
issue of cost, since EPA assumed that the N2O and 
CH4 standards would not result in significant costs for 
existing vehicles. Id. However, EPA expected that manufacturers would 
be able to make technology changes (e.g., calibration or catalyst 
changes) to the few vehicle models not currently meeting the 
N2O and/or CH4 standards in the course of their 
planned vehicle redesign schedules in order to meet the standards.
---------------------------------------------------------------------------

    \184\ 0.030 g/mile CH4 multiplied by a GWP of 25 plus 
0.010 g/mile N2O multiplied by a GWP of 298 results in a 
combined 3.7 g/mile CO2-equivalent value. Manufacturers 
using the default N2O value of 0.10 g/mile prior to MY 
2015 in lieu of measuring N2O would fold in the entire 
0.010 g/mile on a CO2-equivalent basis, or about 3 g/mile 
under the CO2-equivalent option.
---------------------------------------------------------------------------

    Because EPA intended for these standards to be caps with little 
anticipated near-term impact on manufacturer's current product lines, 
EPA requested comment in the heavy-duty vehicle and engine proposal on 
two approaches to provide additional flexibilities in the light-duty 
vehicle program for meeting the N2O and CH4 
standards. 75 FR at 74211. EPA requested comments on the option of 
allowing manufacturers to use the CO2 equivalent approach 
for one pollutant but not the other for their fleet--that is, allowing 
a manufacturer to fold in either CH4 or N2O as 
part of the CO2-equivalent standard. For example, if a 
manufacturer is having trouble complying with the CH4 
standard but not the N2O standard, the manufacturer could 
use the CO2 equivalent option including CH4, but 
choose to comply separately with the applicable N2O cap 
standard.
    EPA also requested comments on an alternative approach of allowing 
manufacturers to use CO2 credits, on a CO2 
equivalent basis, to offset N2O and CH4 emissions 
above the applicable standard. This is similar to the approach proposed 
and being finalized for heavy-duty vehicles as discussed above in 
Section II.E. EPA requested comments on allowing the additional 
flexibility in the light-duty program for MYs 2012-2014 to help 
manufacturers address any near-term issues that they may have with the 
N2O and CH4 standards.
    Commenters providing comment on this issue supported additional 
flexibility for manufacturers, and manufacturers specifically supported 
the heavy-duty vehicle approach of allowing CO2 credits on a 
CO2 equivalent basis to be used to meet the CH4 
and N2O standards. The Alliance of Automobile Manufacturers 
and the American Automotive Policy Council commented that the proposed 
heavy-duty approach represented a significant improvement over the 
approach adopted for light-duty vehicles. Manufacturers support de-
linking N2O and CH4, and commented that the 
formation of the pollutants do not necessarily trend together. 
Manufacturers also commented that a deficit against the N2O 
or CH4 cap would be required to be covered with 
CO2 credits for that model, but the approach does not 
``punish'' manufacturers for using a specific technology (which could 
provide CO2 benefits, e.g., diesel, CNG, etc.) by requiring 
manufacturers to use the CO2-equivalent approach for their 
entire fleet. The Natural Gas Vehicle Interests also supported allowing 
the use of CO2 credits on a CO2-equivalent basis 
for compliance with CH4 standards and urged providing this 
type of flexibility on a permanent basis. The Institute for Policy 
Integrity also submitted comments supportive of providing additional 
flexibility to manufacturers as long as it does not undermine standard 
stringency. This commenter was supportive of either approach discussed 
at proposal.\185\
---------------------------------------------------------------------------

    \185\ The Institute for Policy Integrity questioned whether EPA 
had provided adequate notice of the proposal, given that it appeared 
in the proposed GHG rules for heavy duty vehicles. EPA provided 
notice not only in the preamble, but in the summary of action 
appearing on the first page of the Federal Register notice (``EPA is 
also requesting comment on possible alternative CO2-
equivalent approaches for model year 2012-14 light-duty vehicles''). 
75 FR at 74152. This is ample notice (demonstrated as well by the 
comments received on the issue, including from the Institute).
---------------------------------------------------------------------------

    Manufacturers supported not only adopting the aspects of the heavy-
duty approach noted above, but the entire

[[Page 57194]]

heavy-duty vehicle approach, including two aspects of the program not 
contemplated in EPA's request for comments. First, manufacturers 
commented that EPA incorrectly characterizes the light-duty vehicle 
issues with CH4 and N2O as short-term or early 
lead time issues. For the reasons discussed above, manufacturers 
believe the changes should be made permanent, for the entire 2012-2016 
light-duty rulemaking period and, indeed, in any subsequent rules for 
the light-duty vehicle sector. Second, manufacturers commented that 
N2O and CH4 should be measured on the combined 
55/45 weighting of the FTP and highway cycles, respectively, as these 
cycles are the yardstick for fuel economy and CO2 
measurement. Manufacturers commented that there should not be a 
disconnect between the light-duty and heavy-duty vehicle programs.
    EPA continues to believe that it is appropriate to provide 
additional flexibility to manufacturers to meet the N2O and 
CH4 standards. EPA is thus finalizing provisions allowing 
manufacturers to use CO2 credits, on a CO2-
equivalent basis, to meet the N2O and CH4 
standards, which is consistent with many commenters' preferred 
approach. Manufacturers will have the option of using CO2 
credits to meet N2O and CH4 standards on a test 
group basis as needed for MYs 2012-2016. Because fuel conversion 
manufacturers certifying under 40 CFR part 85, subpart F do not 
participate in ABT programs, EPA is finalizing a compliance option for 
fuel conversion manufacturers to comply with the N2O and 
CH4 standards similar to the credit option just described 
above. The compliance option will allow conversion manufacturers, on an 
individual test group basis, to convert CO2 overcompliance 
into CO2 equivalents of N2O and/or CH4 
that can be subtracted from the CH4 and N2O 
measured values to demonstrate compliance with CH4 and/or 
N2O standards.
    In EPA's request for comments, EPA discussed the new flexibility as 
being needed to address lead time issues for MYs 2012-2014. EPA 
understands that manufacturers are now making technology decisions for 
beyond MY 2014 and that some technologies such as FFVs may have 
difficulty meeting the CH4 and N2O standards, 
presenting manufacturers with difficult decisions of absorbing the 3-4 
g/mile CO2-equivalent emissions fleet wide, making 
significant investments in existing vehicle technologies, or curtailing 
the use of certain technologies.\186\ The CH4 standard, in 
particular, could prove challenging for FFVs because exhaust 
temperatures are lower on E-85 and CH4 is more difficult to 
convert over the catalyst. EPA's initial estimate that these issues 
could be resolved without disrupting product plans by MY 2015 appears 
to be overly optimistic, and therefore EPA is extending the flexibility 
through model year 2016. This change helps ensure that the 
CH4 and N2O standards will not be an obstacle for 
the use of FFVs or other technologies in this timeframe, and at the 
same time, assure that overall fleet average GHG emissions will remain 
at the same level as under the main standards.
---------------------------------------------------------------------------

    \186\ ``Discussions with Vehicle Manufacturers Regarding the 
Light-duty Vehicle CH4 and N2O Standards,'' 
Memorandum from Christopher Lieske to Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    In response to comments from manufacturers and from the Natural Gas 
Vehicle Interests that the changes to the program make sense and should 
be made on a permanent basis (i.e. for model years after 2016), EPA is 
extending this flexibility through MY 2016 as discussed above, but we 
believe it is premature to decide here whether or not these changes 
should be permanent. EPA may consider this issue further in the context 
of new standards for MYs 2017-2025 in the planned future light-duty 
vehicle rulemaking. With regard to comments on changing the test 
procedures over which N2O and CH4 emissions are 
measured to determine compliance with the standards, the level of the 
standards and the test procedures go hand-in-hand and must be 
considered together. Weighting the highway test result with the city 
test result in the emissions measurement would in most cases reduce the 
overall emissions levels for determining compliance with the standards, 
and would thereby, in effect make the standards less stringent. This 
appears to be inappropriate. In addition, EPA did not request comments 
on changing the level of the N2O and CH4 
standards or the test procedures and it is inappropriate to amend the 
standards for that reason as well.
(5) EPA's Final Standards for Direct Emissions From Air Conditioning
    Air conditioning systems contribute to GHG emissions in two ways--
direct emissions through refrigerant leakage and indirect exhaust 
emissions due to the extra load on the vehicle's engine to provide 
power to the air conditioning system. HFC refrigerants, which are 
powerful GHG pollutants, can leak from the A/C system.\187\ This 
includes the direct leakage of refrigerant as well as the subsequent 
leakage associated with maintenance and servicing, and with disposal at 
the end of the vehicle's life.\188\ The most commonly used refrigerant 
in automotive applications--R134a, has a high GWP of 1430.\189\ Due to 
the high GWP of R134a, a small leakage of the refrigerant has a much 
greater global warming impact than a similar amount of emissions of 
CO2 or other mobile source GHGs.
---------------------------------------------------------------------------

    \187\ The United States has submitted a proposal to the Montreal 
Protocol which, if adopted, would phasedown production and 
consumption of HFCs.
    \188\ The U.S. EPA has reclamation requirements for refrigerants 
in place under Title VI of the Clean Air Act.
    \189\ The global warming potentials used in this rule are 
consistent with the 2007 Intergovernmental Panel on Climate Change 
(IPCC) Fourth Assessment Report. At this time, the global warming 
potential values from the 1996 IPCC Second Assessment Report are 
used in the official U.S. greenhouse gas inventory submission to the 
United Nations Framework Convention on Climate Change (per the 
reporting requirements under that international convention, which 
were last updated in 2006).
---------------------------------------------------------------------------

    Heavy-duty air conditioning systems today are similar to those used 
in light-duty applications. However, differences may exist in terms of 
cooling capacity (such that sleeper cabs have larger cabin volumes than 
day cabs), system layout (such as the number of evaporators), and the 
durability requirements due to longer vehicle life. However, the 
component technologies and costs to reduce direct HFC emissions are 
similar between the two types of vehicles.
    The quantity of GHG refrigerant emissions from heavy-duty trucks 
relative to the CO2 emissions from driving the vehicle and 
moving freight is very small. Therefore, a credit approach is not 
appropriate for this segment of vehicles because the value of the 
credit is too small to provide sufficient incentive to utilize feasible 
and cost-effective air conditioning leakage improvements. For the same 
reason, including air conditioning leakage improvements within the main 
standard would in many instances result in lost control opportunities. 
Therefore, EPA is finalizing the proposed requirement that vehicle 
manufacturers meet a low leakage requirement for all air conditioning 
systems installed in 2014 model year and later trucks, with one 
exception. The agency is not finalizing leakage standards for Class 2b-
8 Vocational Vehicles at this time due to the complexity in the build 
process and the potential for different entities besides the chassis 
manufacturer to be involved in the air conditioning system production 
and installation, with

[[Page 57195]]

consequent difficulties in developing a regulatory system.
    For air conditioning systems with a refrigerant capacity greater 
than 733 grams, EPA is finalizing a leakage standard which is a 
``percent refrigerant leakage per year'' to assure that high-quality, 
low-leakage components are used in each air conditioning system design. 
The agency believes that a single ``gram of refrigerant leakage per 
year'' would not fairly address the variety of air conditioning system 
designs and layouts found in the heavy-duty truck sector. EPA is 
finalizing a standard of 1.50 percent leakage per year for heavy-duty 
pickup trucks and vans and Class 7 and 8 tractors. The final standard 
was derived from the vehicles with the largest system refrigerant 
capacity based on the Minnesota GHG Reporting database.\190\ The 
average percent leakage per year of the 2010 model year vehicles is 2.7 
percent. This final level of reduction is roughly comparable to that 
necessary to generate credits under the light-duty vehicle program. See 
75 FR 25426-25427. Since refrigerant leakage past the compressor shaft 
seal is the dominant source of leakage in belt-driven air conditioning 
systems, the agency recognizes that a single ``percent refrigerant 
leakage per year'' is not feasible for systems with a refrigerant 
capacity of 733 grams or lower, as the minimum feasible leakage rate 
does not continue to drop as the capacity or size of the air 
conditioning system is reduced. The fixed leakage from the compressor 
seal and other system devices results in a minimum feasible yearly 
leakage rate, and further reductions in refrigerant capacity (the 
`denominator' in the percent refrigerant leakage calculation) will 
result in a system which cannot meet the 1.50 percent leakage per year 
standard. EPA does not believe that leakage reducing technologies are 
available at this time which would allow lower capacity systems to meet 
the percent per year standard, so we are finalizing a maximum gram per 
year leakage standard of 11.0 grams per year for air conditioning 
systems with a refrigerant capacity of 733 grams or lower. EPA defined 
the standard, as well as the refrigerant capacity threshold, by 
examining the State of Minnesota GHG Reporting Database for the yearly 
leakage rate from 2010 and 2011 model year pickup trucks. In the 
Minnesota data, the average leak rate for the pickup truck category (16 
unique model and refrigerant capacity combinations) was 13.3 grams per 
year, with an average capacity of 654 grams, resulting in an average 
percent refrigerant leakage per year of 2.0 percent. 4 of the 16 model/
capacity combinations in the reporting data achieved a leak rate 11.0 
grams per year or lower, and this was chosen as the maximum yearly leak 
rate, as several manufacturers have demonstrated that this level of 
yearly leakage is feasible. To avoid a discontinuity between the 
``percent leakage'' and ``leak rate'' standards--where one approach 
would be more or less stringent, depending on the refrigerant 
capacity--a refrigerant capacity of 733 grams was chosen as a threshold 
capacity, below which, the leak rate approach can be used. EPA believes 
this approach of having a leak rate standard for lower capacity systems 
and a percent leakage per year standard for higher capacity systems 
will result in reduced refrigerant emissions from all air conditioning 
systems, while still allowing manufacturers the ability to produce low-
leak, lower capacity systems in vehicles which require them.
---------------------------------------------------------------------------

    \190\ The Minnesota refrigerant leakage data can be found at 
http://www.pca.state.mn.us/climatechange/mobileair.html#leakdata.
---------------------------------------------------------------------------

    Manufacturers can choose to reduce A/C leakage emissions in two 
ways. First, they can utilize leak-tight components. Second, 
manufacturers can largely eliminate the global warming impact of 
leakage emissions by adopting systems that use an alternative, low-
Global Warming Potential (GWP) refrigerant. One alternative 
refrigerant, HFO-1234yf, with a GWP of 4, has been approved for use in 
light-duty passenger vehicles under EPA's Significant New Alternatives 
Program (SNAP). While the scope of this SNAP approval does not include 
heavy-duty highway vehicles, we expect that those interested in using 
this refrigerant in other sectors will petition EPA for broader 
approval of its use in all mobile air conditioning systems. In 
addition, the EPA is currently acting on a petition to de-list R-134a 
as an acceptable refrigerant for new, light-duty passenger vehicles. 
The time frame and scale of R-134a de-listing is yet to be determined, 
but any phase-down of R-134a use will likely take place after this 
rulemaking is in effect. Given that HFO-1234yf is yet to be approved 
for heavy-duty vehicles, and that the time frame for the de-listing of 
R-134a is not known, EPA believes that a leakage standard for heavy-
duty vehicles is still appropriate. If future heavy-duty vehicles adopt 
refrigerants other than R-134a, the calculated refrigerant leak rate 
can be adjusted by multiplying the leak rate by the ratio of the GWP of 
the new refrigerant divided by the GWP of the old refrigerant (e.g. for 
HFO-1234yf replacing R-134a, the calculated leak rate would be 
multiplied by 0.0028, or 4 divided by 1430).
    EPA believes that reducing A/C system leakage is both highly cost-
effective and technologically feasible. The availability of low leakage 
components is being driven by the air conditioning program in the 
light-duty GHG rule which apply to 2012 model year and later vehicles. 
The cooperative industry and government Improved Mobile Air 
Conditioning program has demonstrated that new-vehicle leakage 
emissions can be reduced by 50 percent by reducing the number and 
improving the quality of the components, fittings, seals, and hoses of 
the A/C system.\191\ All of these technologies are already in 
commercial use and exist on some of today's systems, and EPA does not 
anticipate any significant improvements in sealing technologies for 
model years beyond 2014. However, EPA has recognized some manufacturers 
utilize an improved manufacturing process for air conditioning systems, 
where a helium leak test is performed on 100 percent of all o-ring 
fittings and connections after final assembly. By leak testing each 
fitting, the manufacturer or supplier is verifying the o-ring is not 
damaged during assembly (which is the primary source of leakage from o-
ring fittings), and when calculating the yearly leak rate for a system, 
EPA will allow a relative emission value equivalent to a `seal washer' 
can be used in place of the value normally used for an o-ring fitting, 
when 100 percent helium leak testing is performed on those fittings. 
While further updates to the SAE J2727 standard may be forthcoming (to 
address new materials and measurement methods for permeation through 
hoses), EPA believes it is appropriate to include the helium leak test 
update to the leakage calculation method at this time.
---------------------------------------------------------------------------

    \191\ Team 1-Refrigerant Leakage Reduction: Final Report to 
Sponsors, SAE, 2007.
---------------------------------------------------------------------------

    Consistent with the light-duty 2012-2016 MY vehicle rule, we are 
estimating costs for leakage control at $18 (2008$) in direct 
manufacturing costs. Including a low complexity indirect cost 
multiplier (ICM) of 1.14 results in costs of $21 in the 2014 model 
year. A/C control technology is considered to be on the flat portion of 
the learning curve, so costs in the 2017 model year will be $19. These 
costs are applied to all heavy-duty pickups and vans, and to all 
combination tractors. EPA views these costs as minimal and the 
reductions of potent GHGs to be easily feasible and reasonable in the 
lead times provided by the final rules.

[[Page 57196]]

    EPA is requiring that manufacturers demonstrate improvements in 
their A/C system designs and components through a design-based method. 
The method for calculating A/C leakage is based closely on an industry-
consensus leakage scoring method, described below. This leakage scoring 
method is correlated to experimentally-measured leakage rates from a 
number of vehicles using the different available A/C components. Under 
the final approach, manufacturers will choose from a menu of A/C 
equipment and components used in their vehicles in order to establish 
leakage scores, which will characterize their A/C system leakage 
performance and calculate the percent leakage per year as this score 
divided by the system refrigerant capacity.
    Consistent with the light-duty rule, EPA is finalizing a 
requirement that a manufacturer will compare the components of its A/C 
system with a set of leakage-reduction technologies and actions that is 
based closely on that being developed through the Improved Mobile Air 
Conditioning program and SAE International (as SAE Surface Vehicle 
Standard J2727, ``HFC-134a, Mobile Air Conditioning System Refrigerant 
Emission Chart,'' August 2008 version). See generally 75 FR 25426. The 
SAE J2727 approach was developed from laboratory testing of a variety 
of A/C related components, and EPA believes that the J2727 leakage 
scoring system generally represents a reasonable correlation with 
average real-world leakage in new vehicles. Like the cooperative 
industry-government program, our final approach will associate each 
component with a specific leakage rate in grams per year that is 
identical to the values in J2727 and then sum together the component 
leakage values to develop the total A/C system leakage. However, in the 
heavy-duty vehicle program, the total A/C leakage score will then be 
divided by the value of the total refrigerant system capacity to 
develop a percent leakage per year. EPA believes that the design-based 
approach will result in estimates of likely leakage emissions 
reductions that will be comparable to those that would eventually 
result from performance-based testing.
    EPA is not specifying a specific in-use standard for leakage, as 
neither test procedures nor facilities exist to measure refrigerant 
leakage from a vehicle's air conditioning system. However, consistent 
with the light-duty rule, where we require that manufacturers attest to 
the durability of components and systems used to meet the 
CO2 standards (see 75 FR 25689), we will require that 
manufacturers of heavy-duty vehicles attest to the durability of these 
systems, and provide an engineering analysis which demonstrates 
component and system durability.
(6) Indirect Emissions From Air Conditioning
    In addition to direct emissions from refrigerant leakage, air 
conditioning systems also create indirect exhaust emissions due to the 
extra load on the vehicle's engine to provide power to the air 
conditioning system. These indirect emissions are in the form of the 
additional CO2 emitted from the engine when A/C is being 
used due to the added loads. Unlike direct emissions which tend to be a 
set annual leak rate not directly tied to usage, indirect emissions are 
fully a function of A/C usage.
    These indirect CO2 emissions are associated with air 
conditioner efficiency, since air conditioners create load on the 
engine. See 74 FR 49529. However, the agencies are not setting air 
conditioning efficiency standards for vocational vehicles, combination 
tractors, or heavy-duty pickup trucks and vans. The CO2 
emissions due to air conditioning systems in these heavy-duty vehicles 
are minimal compared to their overall emissions of CO2. For 
example, EPA conducted modeling of a Class 8 sleeper cab using the GEM 
to evaluate the impact of air conditioning and found that it leads to 
approximately 1 gram of CO2/ton-mile. Therefore, a projected 
24 percent improvement of the air conditioning system (the level 
projected in the light-duty GHG rulemaking), would only reduce 
CO2 emissions by less than 0.3 g CO2/ton-mile, or 
approximately 0.3 percent of the baseline Class 8 sleeper cab 
CO2 emissions.
(7) Ethanol-Fueled and Electric Vehicles
    Current EPA emissions control regulations explicitly apply to 
heavy-duty engines and vehicles fueled by gasoline, methanol, natural 
gas and liquefied petroleum gas. For multi-fueled vehicles they call 
for compliance with requirements established for each consumed fuel. 
This contrasts with EPA's light-duty vehicle regulations that apply to 
all vehicles generally, regardless of fuel type. As we proposed, we are 
revising the heavy-duty vehicle and engine regulations to make them 
consistent with the light-duty vehicle approach, applying standards for 
all regulated criteria pollutants and GHGs regardless of fuel type, 
including application to all-electric vehicles (EVs). This provision 
will take effect in the 2014 model year, and be optional for 
manufacturers in earlier model years. However, to satisfy the CAA 
section 202(a)(3) lead time constraints, the provision will remain 
optional for all criteria pollutants through the 2015 model year. 
Commenters did not oppose this change in EPA regulations.
    This change primarily affects manufacturers of ethanol-fueled 
vehicles (designed to operate on fuels containing at least 50 percent 
ethanol) and EVs. Flex-fueled vehicles (FFVs) designed to run on both 
gasoline and fuel blends with high ethanol content will also be 
impacted, as they will need to comply with requirements for operation 
both on gasoline and ethanol.
    The regulatory requirements we are finalizing today for 
certification on ethanol follow those already established for methanol, 
such as certification to NMHC equivalent standards and waiver of 
certain requirements. We expect testing to be done using the same E85 
test fuel as is used today for light-duty vehicle testing, an 85/15 
blend of commercially-available ethanol and gasoline vehicle test fuel. 
EV certification will also follow light-duty precedents, primarily 
calling on manufacturers to exercise good engineering judgment in 
applying the regulatory requirements, but will not be allowed to 
generate NOX or PM credits.
    This provision is not expected to result in any significant added 
burden or cost. It is already the practice of HD FFV manufacturers to 
voluntarily conduct emissions testing for these vehicles on E85 and 
submit the results as part of their certification application, along 
with gasoline test fuel results. No changes in certification fees are 
being set in connection with this provision. We expect that there will 
be strong incentives for any manufacturer seeking to market these 
vehicles to also want them to be certified: (1) Uncertified vehicles 
carry a disincentive to potential purchasers who typically have the 
benefit to the environment as one of their reasons for considering 
alternative fuels, (2) uncertified vehicles are not eligible for the 
substantial credits they could likely otherwise generate, (3) EVs have 
no tailpipe or evaporative emissions and thus need no added hardware to 
put them in a certifiable configuration, and (4) emissions controls for 
gasoline vehicles and FFVs are also effective on dedicated ethanol-
fueled vehicles, and thus costly development programs and specialized 
components will not be needed; in fact the highly integrated nature of 
modern automotive products make the emission control systems essential 
to reliable vehicle performance.

[[Page 57197]]

    Regarding technological feasibility, as mentioned above, HD FFV 
manufacturers already test on E85 and the resulting data shows that 
they can meet emissions standards on this fuel. Furthermore, there is a 
substantial body of certification data on light-duty FFVs (for which 
testing on ethanol is already a requirement), showing existing emission 
control technology is capable of meeting even the more stringent Tier 2 
standards in place for light-duty vehicles.
(8) Correction to 40 CFR 1033.625
    In a 2008 final rule that set new locomotive and marine engine 
standards, EPA adopted a provision allowing manufacturers to use a 
limited number of nonroad engines to power switch locomotives provided, 
among other things, that ``the engines were certified to standards that 
are numerically lower than the applicable locomotive standards of this 
part (1033).'' (40 CFR 1033.625(a)). The goal of this provision is to 
encourage the replacement of aging, high-emitting switch locomotives 
with new switch locomotives having very low emissions of PM, 
NOX, and hydrocarbons. However, this provision neglected to 
consider the fact that preexisting nonroad engine emission standards 
for CO were set at levels that were slightly numerically higher than 
those for locomotives. The applicable switch locomotive CO standard of 
part 1033 is 3.2 g/kW-hr (2.4 g/hp-hr), while the applicable nonroad 
engine CO standard is 3.5 g/kW-hr (2.6 g/hp-hr). This is the case even 
for the cleanest final Tier 4 nonroad engines that will phase in 
starting in 2014. Thus, nonroad engines cannot be certified to CO 
standards that are numerically lower than the applicable locomotive 
standards, and the nonroad engine provision is rendered practically 
unusable. This matter was brought to EPA's attention by affected engine 
manufacturers.\192\
---------------------------------------------------------------------------

    \192\ See e-mail correspondence from Timothy A. French, EMA, to 
Donald Kopinski and Charles Moulis, U.S. EPA dated 12/8/10, 
``Switcher Locomotive Flexibility'', docket  EPA-HQ-OAR-
2010-0162.
---------------------------------------------------------------------------

    As indicated above, EPA believes that allowing certification of new 
switch locomotive engines to nonroad engine standards will greatly 
reduce emissions from switch locomotives, and EPA does not believe the 
slight difference in CO standards should prevent this environmentally 
beneficial program. EPA is therefore adopting a corrective technical 
amendment in part 1033. The regulation is being amended at Sec.  
1033.625(a)(2) to add the following italicized text: ``The engines were 
certified to PM, NOX, and hydrocarbon standards that are 
numerically lower than the applicable locomotive standards of this 
part.'' This change is a straightforward correction to restore the 
intended usability of the provision and is not expected to have adverse 
environmental impacts, as nonroad engines have CO emissions that are 
typically well below both the nonroad and locomotive emissions 
standards.
(9) Corrections to 40 CFR Part 600
    EPA adopted changes to fuel economy labeling requirements on July 
6, 2011 (76 FR 39478). We are making the following corrections to these 
regulations in 40 CFR part 600:
     We adopted a requirement to use the specifications of SAE 
J1711 for fuel economy testing related to hybrid-electric vehicles. In 
this final rule, we are extending that requirement to the calculation 
provisions in Sec.  600.114-12. This change was inadvertently omitted 
from the earlier final rule.
     We are correcting an equation in Sec.  600.116-12.
     We are removing text describing label content that differs 
from the sample labels that were published with the final rule. The 
sample labels properly characterize the intended label content.
(10) Definition of Urban Bus
    EPA is adding a new section 86.012-2 to revise the definition of 
``urban bus.'' The new definition will treat engines used in urban 
buses the same as engines used in any other HD vehicle application, 
relying on the definitions of primary intended service class for 
defining which standards and useful life apply for bus engines. This 
change is necessary to allow for installation of engines other than 
HHDDE for hybrid bus applications.

III. Feasibility Assessments and Conclusions

    In this section, NHTSA and EPA discuss several aspects of our joint 
technical analyses. These analyses are common to the development of 
each agency's final standards. Specifically we discuss: the development 
of the baseline used by each agency for assessing costs, benefits, and 
other impacts of the standards, the technologies the agencies evaluated 
and their costs and effectiveness, and the development of the final 
standards based on application of technology in light of the attribute 
based distinctions and related compliance measurement procedures. We 
also discuss the agencies' consideration of standards that are either 
more or less stringent than those adopted.
    This program is based on the need to obtain significant oil savings 
and GHG emissions reductions from the transportation sector, and the 
recognition that there are appropriate and cost-effective technologies 
to achieve such reductions feasibly in the model years of this program. 
The decision on what standard to set is guided by each agency's 
statutory requirements, and is largely based on the need for 
reductions, the effectiveness of the emissions control technology, the 
cost and other impacts of implementing the technology, and the lead 
time needed for manufacturers to employ the control technology. The 
availability of technology to achieve reductions and the cost and other 
aspects of this technology are therefore a central focus of this final 
rulemaking.
    CBD submitted several comments on whether NHTSA had met EISA's 
mandate to set standards ``designed to achieve the maximum feasible 
improvement'' and, to that end, appropriately considered feasible 
technologies in setting the stringency level. CBD stated that the 
proposed rule had been improperly limited to currently available 
technology, and that none of the alternatives contained all of the 
available technology, which it argued violated EISA and the CAA. CBD 
also stated that the phase-in schedule violated the technology-forcing 
intention of EISA, and that the agencies misperceived their statutory 
mandates, arguing that the agencies are required to force technological 
innovation through aggressive standards.
    As demonstrated in the standard-specific discussions later in this 
section of the preamble, the standards adopted in the final program are 
consistent with section 202(a) of the CAA and section 32902(k)(2) of 
EISA. With respect to the EPA rules, we note at the outset, that CBD's 
premise that EPA must adopt ``technology-forcing'' standards for heavy-
duty vehicles and engines is wrong. A technology-forcing standard is 
one that is to be based on standards which will be available, rather 
than technology which is presently available. NRDC v. Thomas, 805 F. 2d 
410, 429 (DC Cir. 1986). Clean Air Act provisions requiring ``the 
greatest degree of emission reduction achievable through the 
application of technology which the Administrator determines will be 
available'' are technology-forcing. See e.g., CAA sections 
202(a)(3)(1);\193\

[[Page 57198]]

213(a)(3). Section 202(a)(1) standards are technology-based, but not 
technology-forcing, requiring EPA to issue standards for a vehicle's 
useful life ``after providing such period as the Administrator finds 
necessary to permit the development and application of the requisite 
technology, giving appropriate consideration to the cost of compliance 
within such period.'' See NACAA v. EPA, 489 F. 3d 1221, 1230 (DC Cir. 
2007) upholding EPA's interpretation of similar language in CAA section 
231(a) as providing even greater leeway to weigh the statutory factors 
than if the provision were technology-forcing. See generally 74 FR at 
49464-465 (Sept. 28. 2009); 75 FR at 74171.
---------------------------------------------------------------------------

    \193\ CBD cites the District Court's opinion in Cent. Valley 
Chrysler-Jeep Inc. v. Goldstene, 529 F. Supp. 2d 1151, 1178 (E.D. 
Cal. 2007) for the proposition that standard-setting provisions of 
Title II of the CAA are technology forcing, but the court was citing 
to the technology-forcing provision section 202(a)(3)(A)(i), which 
is not the applicable authority here.
---------------------------------------------------------------------------

    Section 202(a)(1) of course allows EPA to consider application of 
technologies which will be available as well as those presently 
available, id., and EPA exercised that discretion here. For example, as 
shown below, the agencies carefully considered application of hybrid 
technologies and bottoming cycle technologies for a number of the 
standards. Thus, the critical issue is whether EPA's choice of 
technology penetration on which the standards are premised is 
reasonable considering the statutory factors, the key ones being 
technology feasibility, technology availability in the 2014-2018 model 
years (i.e., adequacy of lead time), and technology cost and cost-
effectiveness. EPA has considerable discretion to weigh these factors 
in a reasonable manner (even for provisions which are explicitly 
technology-forcing, see Sierra Club v. EPA, 325 F. 3d 374, 378 (DC Cir. 
2003)), and has done so here.
    With respect to EISA, 49 U.S.C. section 32902(k)(2) directs NHTSA 
to ``determine in a rulemaking proceeding how to implement a commercial 
medium- and heavy-duty on-highway vehicle and work truck fuel 
efficiency improvement program designed to achieve the maximum feasible 
improvement,'' and ``adopt and implement appropriate test methods, 
measurement metrics, fuel economy standards, and compliance and 
enforcement protocols that are appropriate, cost-effective, and 
technologically feasible for commercial medium- and heavy-duty on-
highway vehicles and work trucks'' NHTSA recognizes that Congress 
intended EPCA (and by extension, EISA, which amended it) to be 
technology-forcing. See Center for Auto Safety v. National Highway 
Traffic Safety Admin., 793 F.2d 1322, 1339 (DC Cir. 1986). However, 
NHTSA believes it is important to distinguish between setting ``maximum 
feasible'' standards, as EPCA/EISA requires, and ``maximum 
technologically feasible'' standards, as CBD would have NHTSA do. The 
agency must weigh all of the statutory factors in setting fuel 
efficiency standards, and therefore may not weigh one statutory factor 
in isolation of others.
    Neither EPCA nor EISA define ``maximum feasible'' in the context of 
setting fuel efficiency or fuel economy standards. Instead, NHTSA is 
directed to consider and meet three factors when determining what the 
maximum feasible standards are--``appropriateness, cost-effectiveness, 
and technological feasibility.'' 32902(k)(2). These factors modify 
``feasible'' in the context of the MD/HD rules beyond a plain meaning 
of ``capable of being done.'' See Center for Biological Diversity v. 
National Highway Traffic Safety Admin., 538 F.3d 1172, 1194 (9th Cir. 
2008). With respect to the setting of standards for light-duty 
vehicles, EPCA/EISA ``gives NHTSA discretion to decide how to balance 
the statutory factors--as long as NHTSA's balancing does not undermine 
the fundamental purpose of EPCA: energy conservation.'' Id. at 1195. 
Where Congress has not directly spoken to a potential issue related to 
such a balancing, NHTSA's interpretation must be a ``reasonable 
accommodation of conflicting policies * * * committed to the agency's 
care by the statute.'' Id. (discussing consideration of consumer 
demand) (internal citations omitted). In the context of the agency's 
light-duty vehicle authority, it was determined that Congress delegated 
the process for setting the maximum feasible standard to NHTSA with 
broad guidelines concerning the factors that the agency must consider. 
Id. (internal citations omitted) (emphasis in original). We believe 
that the same conclusion should be drawn about the statutory provisions 
governing the agency's setting of standards for heavy-duty vehicles. 
Those provisions prescribe statutory factors commensurate to, and 
equally broad as, those prescribed for light-duty. Thus, NHTSA believes 
that it is firmly within our discretion to weigh and balance the 
factors laid out in 32902(k) in a way that is technology-forcing, as 
evidenced by these standards promulgated in this final action, but not 
in a way that requires the application of technology which will not be 
available in the lead time provided by the rules, or which is not cost-
effective, or is cost-prohibitive, as CBD evidently deems mandated.
    As detailed below for each regulatory category, NHTSA has 
considered the appropriateness, cost-effectiveness, and technological 
feasibility of the standards in designing a program to achieve the 
maximum feasible fuel efficiency improvement. It believes that each of 
those criteria is met.
    As described in Section I. F. (2) above, the final standards will 
remain in effect indefinitely at their 2018 or 2019 levels, unless and 
until the standards are revised. CBD maintained that this is a per se 
violation of EISA, arguing that, by definition, standards which are not 
updated continually and regularly cannot be considered maximum 
feasible. NHTSA would like to clarify that the NPRM specified that the 
standards would remain indefinitely ``until amended by a future 
rulemaking action.'' NPRM at 74172. Further, as noted above, NHTSA has 
broad discretion to determine the maximum feasible standards. Unlike 
Sec.  32902(b)(3)(B), which applies to automobiles regulated under 
light-duty CAFE, Sec.  32902(k) does not specify a maximum number of 
years that fuel economy standards for heavy-duty vehicles will be in 
place. Consistent with its broad authority to define maximum feasible 
standards, NHTSA interprets its authority as including the discretion 
to define expiration periods where Congress has not otherwise 
specified. This is particularly appropriate for the heavy-duty sector, 
where fuel efficiency regulation is unprecedented. NHTSA believes that 
it would be unwise to set an expiration period for this first 
rulemaking absent both Congressional direction and a known compelling 
reason for setting a specific date.
    NHTSA believes that the phase-in schedules provide an appropriate 
balance between the technology-forcing purpose of the statute and EISA-
mandated considerations of economic practicability. NHTSA recognizes, 
as noted in the case above, that balancing each statutory factor in 
order to set the maximum feasible standards means that the agency must 
engage in a ``reasonable accommodation of conflicting policies.'' See 
538 F.3d at 1195, supra. Here, the agency has determined that the 
phase-in schedules are one such reasonable accommodation.
    Navistar commented generally that the proposed rule was not 
technologically feasible, stating that the proposed standards assume 
technologies which are not in production for all manufacturers. This is

[[Page 57199]]

not the test for technical feasibility. Under the Clean Air Act, EPA 
needs only to outline a technical path toward compliance with a 
standard, giving plausible reasons for its belief that technology will 
either be developed or applied in the requisite period. NRDC v. EPA, 
655 F. 2d 318, 333-34 (DC Cir. 1981). EPA has done so here with respect 
to the alternative engine standards of particular concern to 
Navistar.\194\ Similarly, NHTSA has previously interpreted 
``technological feasibility'' to mean ``whether a particular method of 
improving fuel economy can be available for commercial application in 
the model year for which a standard is being established.'' 74 FR 
14196, 14216. NHTSA has further clarified that the consideration of 
technological feasibility ``does not mean that the technology must be 
available or in use when a standard is proposed or issued.'' Center for 
Auto Safety v. National Highway Traffic Safety Admin., 793 F.2d 1322, 
1325 n12 (DC Cir. 1986), quoting 42 FR 63, 184, 63, 188 (1977).
---------------------------------------------------------------------------

    \194\ See 40 CFR 1036.620.
---------------------------------------------------------------------------

    Consistent with these previous interpretations, NHTSA believes that 
a technology does not necessarily need to be currently available or in 
use for all regulated parties to be ``technologically feasible'' for 
this program, as long as it is reasonable to expect, based on the 
evidence before the agency, that the technology will be available in 
the model year in which the relevant standard takes effect. The 
agencies provide multiple technology pathways for compliance with a 
standard, allowing each manufacturer to develop technologies which fit 
their current production and research, and the standards are based on 
fleet penetration rates of those technologies. As discussed below, it 
is reasonable to assume that all the technologies on whose performance 
the standards are premised will be available over the period the 
standards are in effect.
    The Institute for Policy Integrity (IPI) commented that the 
agencies should increase the scope and stringency of the final rule to 
the point at which net benefits would be maximized, citing Executive 
Orders 12866 and 13563. EOs 12866 and 13563 instruct agencies, to the 
extent permitted by law, to select, among other things, the regulatory 
approaches which maximize net benefits. NHTSA agrees with IPI about the 
applicability of these EOs and has made every effort to incorporate 
their guidance in drafting this rule.
    Though IPI agreed that the proposed rule was cost-benefit 
justified, IPI further stated that the agencies must implement an 
alternative that provides the maximum net benefits. The agencies 
believe that standards that maximized net benefits would be beyond the 
point of technological feasibility for this first phase of the HD 
National Program. The standards already require the maximum feasible 
fuel efficiency improvements for the HD fleet in the 2014-2018 time 
frame. Thus, even though, the final standards are highly cost-
effective, and standards that maximized net benefits would likely be 
more stringent than those being promulgated in this final action, NHTSA 
believes that standards that maximized net benefits would not be 
appropriate or technologically feasible in the rulemaking time frame. 
The Executive Orders cited by IPI cannot and do not require an agency 
to select a regulatory alternative that is inconsistent with its 
statutory obligations. Thus, the standards adopted in the final rules 
are consistent with the agencies' respective statutory authorities, and 
are not established at levels which are infeasible or cost-ineffective.
    Here, the focus of the standards is on applying fuel efficiency and 
emissions control technology to reduce fuel consumption, CO2 
and other greenhouse gases. Vehicles combust fuel to generate power 
that is used to perform two basic functions: (1) Transport the truck 
and its payload, and (2) operate various accessories during the 
operation of the truck such as the PTO units. Engine-based technology 
can reduce fuel consumption and CO2 emissions by improving 
engine efficiency, which increases the amount of power produced per 
unit of fuel consumed. Vehicle-based technology can reduce fuel 
consumption and CO2 emissions by increasing the vehicle 
efficiency, which reduces the amount of power demanded from the engine 
to perform the truck's primary functions.
    Our technical work has therefore focused on both engine efficiency 
improvements and vehicle efficiency improvements. In addition to fuel 
delivery, combustion, and aftertreatment technology, any aspect of the 
truck that affects the need for the engine to produce power must also 
be considered. For example, the drag due to aerodynamics and the 
resistance of the tires to rolling both have major impacts on the 
amount of power demanded of the engine while operating the vehicle.
    The large number of possible technologies to consider and the 
breadth of vehicle systems that are affected mean that consideration of 
the manufacturer's design and production process plays a major role in 
developing the final standards. Engine and vehicle manufacturers 
typically develop many different models based on a limited number of 
platforms. The platform typically consists of a common engine or truck 
model architecture. For example, a common engine platform may contain 
the same configuration (such as inline), number of cylinders, 
valvetrain architecture (such as overhead valve), cylinder head design, 
piston design, among other attributes. An engine platform may have 
different calibrations, such as different power ratings, and different 
aftertreatment control strategies, such as exhaust gas recirculation 
(EGR) or selective catalytic reduction (SCR). On the other hand, a 
common vehicle platform has different meanings depending on the market. 
In the heavy-duty pickup truck market, each truck manufacturer usually 
has only a single pickup truck platform (for example the F series by 
Ford) with common chassis designs and shared body panels, but with 
variations on load capacity of the axles, the cab configuration, tire 
offerings, and powertrain options. Lastly, the combination tractor 
market has several different platforms and the trucks within each 
platform (such as LoneStar by Navistar) have less commonality. Tractor 
manufacturers will offer several different options for bumpers, 
mirrors, aerodynamic fairing, wheels, and tires, among others. However, 
some areas such as the overall basic aerodynamic design (such as the 
grill, hood, windshield, and doors) of the tractor are tied to tractor 
platform.
    The platform approach allows for efficient use of design and 
manufacturing resources. Given the very large investment put into 
designing and producing each truck model, manufacturers of heavy-duty 
pickup trucks and vans typically plan on a major redesign for the 
models every 5 years or more (a key consideration in the choice of the 
five model year duration during which the vehicle standards are phased 
in). Recently, EPA's non-GHG heavy-duty engine program provided new 
emissions standards every three model years. Heavy-duty engine and 
truck manufacturer product plans typically have fallen into three year 
cycles to reflect this regime. While the recent non-GHG emissions 
standards can be handled generally with redesigns of engines and 
trucks, a complete redesign of a new heavy-duty engine or truck 
typically occurs on a slower cycle and often does not align in time due 
to the fact that the manufacturer of engines

[[Page 57200]]

differs from the truck manufacturer. At the redesign stage, the 
manufacturer will upgrade or add all of the technology and make most 
other changes supporting the manufacturer's plans for the next several 
years, including plans related to emissions, fuel efficiency, and 
safety regulations.
    A redesign of either engine or truck platforms often involves a 
package of changes designed to work together to meet the various 
requirements and plans for the model for several model years after the 
redesign. This often involves significant engineering, development, 
manufacturing, and marketing resources to create a new product with 
multiple new features. In order to leverage this significant upfront 
investment, manufacturers plan vehicle redesigns with several model 
years of production in mind. Vehicle models are not completely static 
between redesigns as limited changes are often incorporated for each 
model year. This interim process is called a refresh of the vehicle and 
it generally does not allow for major technology changes although more 
minor ones can be done (e.g., small aerodynamic improvements, etc). 
More major technology upgrades that affect multiple systems of the 
vehicle thus occur at the vehicle redesign stage and not in the time 
period between redesigns.
    As discussed below, there are a wide variety of CO2 and 
fuel consumption reducing technologies involving several different 
systems in the engine and vehicle that are available for consideration. 
Many can involve major changes to the engine or vehicle, such as 
changes to the engine block and cylinder heads or changes in vehicle 
shape to improve aerodynamic efficiency. Incorporation of such 
technologies during the periodic engine, transmission or vehicle 
redesign process would allow manufacturers to develop appropriate 
packages of technology upgrades that combine technologies in ways that 
work together and fit with the overall goals of the redesign. By 
synchronizing with their multi-year planning process, manufacturers can 
avoid the large increase in resources and costs that would occur if 
technology had to be added outside of the redesign process. We 
considered redesign cycles both in our costing and in assessing needed 
the lead time required.
    As described below, the vast majority of technology on whose 
performance the final standards are predicated is commercially 
available and already being utilized to a limited extent across the 
heavy-duty fleet. Therefore the majority of the emission and fuel 
consumption reductions which would result from these final rules would 
result from the increased use of these technologies. EPA and NHTSA also 
believe that these final rules will encourage the development and 
limited use of more advanced technologies, such as advanced 
aerodynamics and hybrid powertrains in some vocational vehicle 
applications.
    In evaluating truck efficiency, NHTSA and EPA have excluded 
consideration of standards which could result in fundamental changes in 
the engine or vehicle's performance. Put another way, none of the 
technology pathways underlying the final standards involve any 
alteration in vehicle utility. For example, the agencies did not 
consider approaches that would necessitate reductions in engine power 
or otherwise limit truck performance. The agencies have thus limited 
the assessment of technical feasibility and resultant vehicle cost to 
technologies which maintain freight utility. Similarly, the agencies' 
choice of attributes on which to base the standards, and the metrics 
used to measure them, are consciously adopted to preserve the utility 
of heavy-duty vehicles and engines.
    The agencies worked together to determine component costs for each 
of the technologies and build up the costs accordingly. For costs, the 
agencies considered both the direct or ``piece'' costs and indirect 
costs of individual components of technologies. For the direct costs, 
the agencies followed a bill of materials approach utilized by the 
agencies in the light-duty 2012-16 MY vehicle rule. A bill of 
materials, in a general sense, is a list of components or sub-systems 
that make up a system--in this case, an item of technology which 
reduces GHG emissions and fuel consumption. In order to determine what 
a system costs, one of the first steps is to determine its components 
and what they cost. NHTSA and EPA estimated these components and their 
costs based on a number of sources for cost-related information. In 
general, the direct costs of fuel consumption-improving technologies 
for heavy-duty pickups and vans are consistent with those used in the 
light-duty 2012-2016 MY vehicle rule, except that the agencies have 
scaled up certain costs where appropriate to accommodate the larger 
size and/or loads placed on parts and systems in the heavy-duty classes 
relative to the light-duty classes. For loose heavy-duty engines, the 
agencies have consulted various studies and have exercised engineering 
judgment when estimating direct costs. For technologies expected to be 
added to vocational vehicles and combination tractors, the agencies 
have again consulted various studies and have used engineering judgment 
to arrive at direct cost estimates. Once costs were determined, they 
were adjusted to ensure that they were all expressed in 2009 dollars 
using a ratio of gross domestic product deflators for the associated 
calendar years.
    Indirect costs were accounted for using the ICM approach explained 
in Chapter 2 of the RIA, rather than using the traditional Retail Price 
Equivalent (RPE) multiplier approach. For the heavy-duty pickup truck 
and van cost projections in this final action, the agencies have used 
ICMs developed for light-duty vehicles (with the exception that here 
return on capital has been incorporated into the ICMs, where it had not 
been in the light-duty rule) primarily because the manufacturers 
involved in this segment of the heavy-duty market are the same 
manufacturers that build light-duty trucks. For the Class 7 and 8 
tractor, vocational vehicle, and heavy-duty engine cost projections in 
this final rulemaking, EPA contracted with RTI International to update 
EPA's methodology for accounting for indirect costs associated with 
changes in direct manufacturing costs for heavy-duty engine and truck 
manufacturers.\195\ In addition to the indirect cost multipliers 
varying by complexity and time frame, there is no reason to expect that 
the multipliers would be the same for engine manufacturers as for truck 
manufacturers. The report from RTI provides a description of the 
methodology, as well as calculations of new indirect cost multipliers. 
The multipliers used here include a factor of 5 percent of direct costs 
representing the return on capital for heavy-duty engines and truck 
manufacturers. These indirect cost multipliers are intended to be used, 
along with calculations of direct manufacturing costs, to provide 
improved estimates of the full additional costs associated with new 
technologies. The agencies did not receive any adverse comments related 
to this methodology.
---------------------------------------------------------------------------

    \195\ RTI International. Heavy-duty Truck Retail Price 
Equivalent and Indirect Cost Multipliers. July 2010.
---------------------------------------------------------------------------

    Details of the direct and indirect costs, and all applicable ICMs, 
are presented in Chapter 2 of the RIA. In addition, for details on the 
ICMs, please refer to the RTI report (See Docket ID EPA-HQ-OAR-2010-
0162-0283). Importantly, the agencies have revised the ICM factors and 
the way that indirect costs are calculated using the ICMs. As a result, 
the ICM factors are now higher, the indirect costs are higher and, 
therefore, technology costs are

[[Page 57201]]

higher. The changes made to the ICMs and the indirect cost calculations 
are discussed in Section VIII of this preamble and are detailed in 
Chapter 2 of the RIA.
    EPA and NHTSA believe that the emissions reductions called for by 
the final standards are technologically feasible at reasonable costs 
within the lead time provided by the final standards, reflecting our 
projections of widespread use of commercially available technology. 
Manufacturers may also find additional means to reduce emissions and 
lower fuel consumption beyond the technical approaches we describe 
here. We encourage such innovation through provisions in our 
flexibility program as discussed in Section IV.
    The remainder of this section describes the technical feasibility 
and cost analysis in greater detail. Further detail on all of these 
issues can be found in the joint RIA Chapter 2.

A. Class 7-8 Combination Tractor

    Class 7 and 8 tractors are used in combination with trailers to 
transport freight.\196\ The variation in the design of these tractors 
and their typical uses drive different technology solutions for each 
regulatory subcategory. The agencies are adopting provisions to treat 
vocational tractors as vocational vehicles instead of as combination 
tractors, as noted in Section II.B. The focus of this section is on the 
feasibility of the standards for combination tractors, not the 
vocational tractors.
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    \196\ ``Tractor'' is defined in 49 CFR 571.3 to mean ``a truck 
designed primarily for drawing other motor vehicles and not so 
constructed as to carry a load other than a part of the weight of 
the vehicle and the load so drawn.''
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    EPA and NHTSA collected information on the cost and effectiveness 
of fuel consumption and CO2 emission reducing technologies 
from several sources. The primary sources of information were the 2010 
National Academy of Sciences report of Technologies and Approaches to 
Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles,\197\ 
TIAX's assessment of technologies to support the NAS panel report,\198\ 
EPA's Heavy-duty Lumped Parameter Model,\199\ the analysis conducted by 
the Northeast States Center for a Clean Air Future, International 
Council on Clean Transportation, Southwest Research Institute and TIAX 
for reducing fuel consumption of heavy-duty long haul combination 
tractors (the NESCCAF/ICCT study),\200\ and the technology cost 
analysis conducted by ICF for EPA.\201\ Following on the EISA of 2007, 
the National Research Council appointed a NAS committee to assess 
technologies for improving fuel efficiency of heavy-duty vehicles to 
support NHTSA's rulemaking. The 2010 NAS report assessed current and 
future technologies for reducing fuel consumption, how the technologies 
could be implemented, and identified the potential cost of such 
technologies. The NAS panel contracted with TIAX to perform an 
assessment of technologies which provide potential fuel consumption 
reductions in heavy-duty trucks and engines and the technologies' 
associated capital costs. Similar to the Lumped Parameter model which 
EPA developed to assess the impact and interactions of GHG and fuel 
consumption reducing technologies for light-duty vehicles, EPA 
developed a new version of that model to specifically address the 
effectiveness and interactions of the final pickup truck and light 
heavy-duty engine technologies. The NESCAFF/ICCT study assessed 
technologies available in 2012 through 2017 to reduce CO2 
emissions and fuel consumption of line haul combination tractors and 
trailers. Lastly, the ICF report focused on the capital, maintenance, 
and operating costs of technologies currently available to reduce 
CO2 emissions and fuel consumption in heavy-duty engines, 
combination tractors, and vocational vehicles.
---------------------------------------------------------------------------

    \197\ Committee to Assess Fuel Economy Technologies for Medium- 
and Heavy-Duty Vehicles; National Research Council; Transportation 
Research Board (2010). Technologies and Approaches to Reducing the 
Fuel Consumption of Medium- and Heavy-Duty Vehicles. (``The NAS 
Report'') Washington, DC, The National Academies Press. Available 
electronically from the National Academy Press Web site at http://www.nap.edu/catalog.php?record_id=12845.
    \198\ TIAX, LLC. ``Assessment of Fuel Economy Technologies for 
Medium- and Heavy-Duty Vehicles,'' Final Report to National Academy 
of Sciences, November 19, 2009.
    \199\ U.S. EPA. Heavy-duty Lumped Parameter Model.
    \200\ NESCCAF, ICCT, Southwest Research Institute, and TIAX. 
Reducing Heavy-Duty Long Haul Combination Truck Fuel Consumption and 
CO2 Emissions. October 2009.
    \201\ ICF International. ``Investigation of Costs for Strategies 
to Reduce Greenhouse Gas Emissions for Heavy-Duty On-Road 
Vehicles.'' July 2010. Docket Number EPA-HQ-OAR-2010-0162-0283.
---------------------------------------------------------------------------

(1) What technologies did the agencies consider to reduce the 
CO2 emissions and fuel consumption of combination tractors?
    Manufacturers can reduce CO2 emissions and fuel 
consumption of combination tractors through use of, among others, 
engine, aerodynamic, tire, extended idle, and weight reduction 
technologies. The standards in the final rules are premised on use of 
these technologies. The agencies note that SmartWay trucks are 
available today which incorporate the technologies on whose performance 
the final standards are based. We will also discuss other technologies 
that could potentially be used, such as vehicle speed limiters, 
although we are not basing the final standards on their use for the 
model years covered by this rulemaking, for various reasons discussed 
below.
    In this section we discuss the baseline tractor and engine 
technologies for the 2010 model year, and then discuss the types of 
technologies that the agencies considered to improve performance 
relative to this baseline, while Section III.A.2 discusses the 
technology packages the agencies used to determine the final standard 
levels.
(a) Baseline Tractor & Tractor Technologies
    Baseline tractor: The agencies developed the baseline tractor to 
represent the average 2010 model year tractor. Today there is a large 
spread in aerodynamics in the new tractor fleet. Trucks sold may 
reflect so-called classic styling (as described in Section II.B.3.c), 
or may be sold with aerodynamic packages. Based on our review of 
current truck model configurations and Polk data provided through MJ 
Bradley,\202\ we believe the aerodynamic configuration of the baseline 
new truck fleet is approximately 25 percent Bin I, 70 percent Bin II, 
and 5 percent Bin III (as these bin configurations are explained above 
in Section II.B. (2)(c). The baseline Class 7 and 8 day cab tractor 
consists of an aerodynamic package which closely resembles the Bin I 
package described in Section II.B. (2)(c), baseline tire rolling 
resistance of 7.8 kg/metric ton for the steer tire and 8.2 kg/metric 
ton,\203\ dual tires with steel wheels on the drive axles, and no 
vehicle speed limiter. The baseline tractor for the Class 8 sleeper 
cabs contains the same aerodynamic and tire rolling resistance 
technologies as the baseline day cab, does not include vehicle speed 
limiters, and does not include an idle reduction technology. The 
agencies assume the baseline transmission is a 10 speed manual. The 
agencies received a comment from the ICCT stating that the 0.69 Cd 
baseline for high roof sleepers published in the NPRM is higher than 
existing studies show. ICCT cited three studies

[[Page 57202]]

including a Society of Automotive Engineering paper showing a lower Cd 
for tractor trailers. The agencies based the average Cd for high roof 
sleepers on available in use fleet composition data, combined with an 
assessment of drag coefficient for different truck configurations. The 
agencies are finalizing the 0.69 baseline Cd for high roof sleeper 
based on our assessment for the NPRM. However, we will continue to 
gather information on the composition of the in-use fleet and may alter 
the baseline in a future action, should more data become available that 
demonstrates our estimate is incorrect.
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    \202\ MJ Bradley. Heavy-duty Market Analysis. May 2009. Page 10.
    \203\ U.S. Environmental Protection Agency. SmartWay Transport 
Partnership July 2010 e-update accessed July 16, 2010, from http://www.epa.gov/smartwaylogistics/newsroom/documents/e-update-july-10.pdf.
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    Performance from this baseline can be improved by the use of the 
following technologies:
    Aerodynamic technologies: There are opportunities to reduce 
aerodynamic drag from the tractor, but it is difficult to assess the 
benefit of individual aerodynamic features. Therefore, reducing 
aerodynamic drag requires optimizing of the entire system. The 
potential areas to reduce drag include all sides of the truck--front, 
sides, top, rear and bottom. The grill, bumper, and hood can be 
designed to minimize the pressure created by the front of the truck. 
Technologies such as aerodynamic mirrors and fuel tank fairings can 
reduce the surface area perpendicular to the wind and provide a smooth 
surface to minimize disruptions of the air flow. Roof fairings provide 
a transition to move the air smoothly over the tractor and trailer. 
Side extenders can minimize the air entrapped in the gap between the 
tractor and trailer. Lastly, underbelly treatments can manage the flow 
of air underneath the tractor. As discussed in the TIAX report, the 
coefficient of drag (Cd) of a SmartWay sleeper cab high roof tractor is 
approximately 0.60, which is a significant improvement over a truck 
with no aerodynamic features which has a Cd value of approximately 
0.80.\204\ The GEM demonstrates that an aerodynamic improvement of a 
Class 8 high roof sleeper cab with a Cd value of 0.60 (which represents 
a Bin III tractor) provides a 5 percent reduction in fuel consumption 
and CO2 emissions over a truck with a Cd of 0.68.
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    \204\ See TIAX, Note 198, Page 4-50.
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    Lower Rolling Resistance Tires: A tire's rolling resistance results 
from the tread compound material, the architecture and materials of the 
casing, tread design, the tire manufacturing process, and its operating 
conditions (surface, inflation pressure, speed, temperature, etc.). 
Differences in rolling resistance of up to 50 percent have been 
identified for tires designed to equip the same vehicle. The baseline 
rolling resistance coefficient for today's fleet is 7.8 kg/metric ton 
for the steer tire and 8.2 kg/metric ton for the drive tire, based on 
sales weighting of the top three manufacturers based on market 
share.\205\ Since 2007, SmartWay trucks have had steer tires with 
rolling resistance coefficients of less than 6.6 kg/metric ton for the 
steer tire and less than 7.0 kg/metric ton for the drive tire.\206\ Low 
rolling resistance (LRR) drive tires are currently offered in both dual 
assembly and single wide-base configurations. Single wide tires can 
offer rolling resistance reduction along with improved aerodynamics and 
weight reduction. The GEM demonstrates that replacing baseline tractor 
tires with tires which meet the Bin I level provides approximately a 4 
percent reduction in fuel consumption and CO2 emissions over 
the prescribed test cycle, as shown in RIA Chapter 2, Figure 2-2.
---------------------------------------------------------------------------

    \205\ See SmartWay, Note 203, above.
    \206\ Ibid.
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    Weight Reduction: Reductions in vehicle mass reduce fuel 
consumption and GHGs by reducing the overall vehicle mass to be 
accelerated and also through increased vehicle payloads which can allow 
additional tons to be carried by fewer trucks consuming less fuel and 
producing lower emissions on a ton-mile basis. Initially for proposal, 
the agencies considered evaluating vehicle mass reductions on a total 
vehicle basis for combination tractors.\207\ The agencies considered 
defining a baseline vehicle curb weight and the GEM would have used the 
vehicle's actual curb weight to calculate the increase or decrease in 
fuel consumption related to the overall vehicle mass relative to that 
baseline. After considerable evaluation of this issue, including 
discussions with the industry, we decided it would not be possible to 
define a single vehicle baseline mass for the tractors that would be 
appropriate and representative. Actual vehicle curb weights for these 
classes of vehicles vary by thousands of pounds dependent on customer 
features added to vehicles and critical to the function of the vehicle 
in the particular vocation in which it is used. This is true of 
vehicles such as Class 8 tractors considered in this section that may 
appear to be relatively homogenous but which in fact are quite 
heterogeneous.
---------------------------------------------------------------------------

    \207\ The agencies are using the approach of evaluating total 
vehicle mass for heavy-duty pickups and vans where we have more data 
on the current fleet vehicle mass.
---------------------------------------------------------------------------

    This reality led us to the solution we proposed. In the proposal, 
we reflected mass reductions for specific technology substitutions 
(e.g., installing aluminum wheels instead of steel wheels) where we 
could with confidence verify the mass reduction information provided by 
the manufacturer even though we cannot estimate the actual curb weight 
of the vehicle. In this way, we accounted for mass reductions where we 
can accurately account for its benefits.
    For the final rules, based on evaluation of the comments, the 
agencies developed an expanded list of weight reduction opportunities, 
from which the sum of the weight reduction from the technologies 
installed on a specific tractor can be input into the GEM as listed in 
Table II-9 in Section II. The list includes additional components, but 
not materials, from those proposed in the NPRM. For high strength 
steel, the weight reduction value is equal to 10 percent of the 
presumed baseline component weight, as the agencies used a conservative 
value based on the DOE report. We recognize that there may be 
additional potential for weight reduction in new high strength steel 
components which combine the reduction due to the material substitution 
along with improvements in redesign, as evidenced by the studies done 
for light-duty vehicles. In the development of the high strength steel 
component weights, we are only assuming a reduction from material 
substitution and no weight reduction from redesign, since we do not 
have any data specific to redesign of heavy-duty components nor do we 
have a regulatory mechanism to differentiate between material 
substitution and improved design. We are finalizing for wheels that 
both aluminum and light weight aluminum are eligible to be used as 
light-weight materials. Only aluminum and not light weight aluminum can 
be used as a light-weight material for other components. The reason for 
this is data was available for light weight aluminum for wheels but was 
not available for other components.
    As explained in Section II.B above, the agencies continue to 
believe that the 400 pound weight target is appropriate for setting the 
final combination tractor CO2 emissions and fuel consumption 
standards. The agencies agree with the commenter that 400 pounds of 
weight reduction without the use of single wide tires may not be 
achievable for all tractor configurations. The agencies have expanded 
the list of weight reduction components which can be input into the GEM 
in order to provide the manufacturers with additional means to comply 
with the combination tractors and to further encourage reductions in 
vehicle weight. The agencies considered increasing the

[[Page 57203]]

target value beyond 400 pounds given the additional reduction potential 
identified in the expanded technology list; however, lacking 
information on the capacity for the industry to change to these light 
weight components across the board by the 2014 model year, we have 
decided to maintain the 400 pound target. The agencies intend to 
continue to study the potential for additional weight reductions in our 
future work considering a second phase of truck fuel efficiency and GHG 
regulations.
    A weight reduction of 400 pounds applied to a truck which travels 
at 70,000 pounds will have a minimal impact on fuel consumption. 
However, for trucks which operate at the maximum GVWR which occurs 
approximately in one third of truck miles travelled, a reduced tare 
weight will allow for additional payload to be carried. The GEM 
demonstrates that a weight reduction of 400 pounds applied to the 
payload tons for one third of the trips provides a 0.3 percent 
reduction in fuel consumption and CO2 emissions over the 
prescribed test cycle, as shown in Figure 2-3 of RIA Chapter 2.
    Extended Idle Reduction: Auxiliary power units (APU)s, fuel 
operated heaters, battery supplied air conditioning, and thermal 
storage systems are among the technologies available today to reduce 
main engine extended idling from sleeper cabs. Each of these 
technologies reduces the baseline fuel consumption during idling from a 
truck without this equipment (the baseline) from approximately 0.8 
gallons per hour (main engine idling fuel consumption rate) to 
approximately 0.2 gallons per hour for an APU.\208\ EPA and NHTSA agree 
with the TIAX assessment of a 6 percent reduction in overall fuel 
consumption reduction.\209\
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    \208\ See the RIA Chapter 2 for details.
    \209\ See the 2010 NAS Report, Note 197, above, at 128.
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    Vehicle Speed Limiters: Fuel consumption and GHG emissions increase 
proportional to the square of vehicle speed. Therefore, lowering 
vehicle speeds can significantly reduce fuel consumption and GHG 
emissions. A vehicle speed limiter (VSL), which limits the vehicle's 
maximum speed, is a simple technology that is utilized today by some 
fleets (though the typical maximum speed setting is often higher than 
65 mph). The GEM shows that using a vehicle speed limiter set at 62 mph 
on a sleeper cab tractor will provide a 4 percent reduction in fuel 
consumption and CO2 emissions over the prescribed test 
cycles over a baseline vehicle without a VSL or one set above 65 
mph.\210\
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    \210\ The Center for Biological Diversity thought that the 
agencies; were limiting their consideration of vehicle speed 
limiters as a potential control technology due to perceived legal 
constraints. As noted above, vehicle speed limiters are a potential 
control technology for heavy duty vehicles and there is no statutory 
bar on either agency considering the performance of VSLs in 
developing the standards.
---------------------------------------------------------------------------

    Transmission: As discussed in the 2010 NAS report, automatic and 
automated manual transmissions may offer the ability to improve vehicle 
fuel consumption by optimizing gear selection compared to an average 
driver. However, as also noted in the report and in the supporting TIAX 
report, the improvement is very dependent on the driver of the truck, 
such that reductions ranged from 0 to 8 percent.\211\ Well-trained 
drivers would be expected to perform as well or even better than an 
automatic transmission since the driver can see the road ahead and 
anticipate a changing stoplight or other road condition that an 
automatic transmission can not anticipate. However, poorly-trained 
drivers that shift too frequently or not frequently enough to maintain 
optimum engine operating conditions could be expected to realize 
improved in-use fuel consumption by switching from a manual 
transmission to an automatic or automated manual transmission. Although 
we believe there may be real benefits in reduced fuel consumption and 
GHG emissions through the application of dual clutch, automatic or 
automated manual transmission technology, we are not reflecting this 
potential improvement in our standard setting or in our compliance 
model. We have taken this approach because we cannot say with 
confidence what level of performance improvement to expect.
---------------------------------------------------------------------------

    \211\ See TIAX, Note 198, above at 4-70.
---------------------------------------------------------------------------

    Low Friction Transmission, Axle, and Wheel Bearing Lubricants: The 
2010 NAS report assessed low friction lubricants for the drivetrain as 
a 1 percent improvement in fuel consumption based on fleet 
testing.\212\ The light-duty 2012-16 MY vehicle rule and the pickup 
truck portion of this program estimate that low friction lubricants can 
have an effectiveness value between 0 and 1 percent compared to 
traditional lubricants. However, it is not clear if in many heavy-duty 
applications these low friction lubricants could have competing 
requirements like component durability issues requiring specific 
lubricants with different properties than low friction.
---------------------------------------------------------------------------

    \212\ See the 2010 NAS Report, Note 197, page 67.
---------------------------------------------------------------------------

    Hybrid: Hybrid powertrain development in Class 7 and 8 tractors has 
been limited to a few manufacturer demonstration vehicles to date. One 
of the key benefit opportunities for fuel consumption reduction with 
hybrids is less fuel consumption when a vehicle is idling, but the 
standard is already premised on use of extended idle reduction so use 
of hybrid technology would duplicate many of the same emission 
reductions attributable to extended idle reduction. NAS estimated that 
hybrid systems would cost approximately $25,000 per tractor in the 2015 
through the 2020 time frame and provide a potential fuel consumption 
reduction of 10 percent, of which 6 percent is idle reduction which can 
be achieved (less expensively) through the use of other idle reduction 
technologies.\213\ The limited reduction potential outside of idle 
reduction for Class 8 sleeper cab tractors is due to the mostly highway 
operation and limited start-stop operation. Due to the high cost and 
limited benefit during the model years at issue in this action (as well 
as issues regarding sufficiency of lead time (see Section III.2 (a) 
below), the agencies are not including hybrids in assessing standard 
stringency (or as an input to GEM). However as discussed in Section IV, 
the agencies are providing incentives to encourage the introduction of 
advanced technologies including hybrid powertrains in appropriate 
applications.
---------------------------------------------------------------------------

    \213\ See the 2010 NAS Report, Note 197, page 128.
---------------------------------------------------------------------------

    Management: The 2010 NAS report noted many operational 
opportunities to reduce fuel consumption, such as driver training and 
route optimization. The agencies have included discussion of several of 
these strategies in RIA Chapter 2, but are not using these approaches 
or technologies in the standard setting process. The agencies are 
looking to other resources, such as EPA's SmartWay Transport 
Partnership and regulations that could potentially be promulgated by 
the Federal Highway Administration and the Federal Motor Carrier Safety 
Administration, to continue to encourage the development and 
utilization of these approaches.
(b) Baseline Engine & Engine Technologies
    The baseline engine for the Class 8 tractors is a Heavy Heavy-Duty 
Diesel engine with 15 liters of displacement which produces 455 
horsepower. The agencies are using a smaller baseline engine for the 
Class 7 tractors because of the lower combined weights of this class of 
vehicles require less power, thus the baseline is an 11L engine with 
350 horsepower. The agencies

[[Page 57204]]

developed the baseline diesel engine as a 2010 model year engine with 
an aftertreatment system which meets EPA's 0.20 grams of 
NOX/bhp-hr standard with an SCR system along with EGR and 
meets the PM emissions standard with a diesel particulate filter with 
active regeneration. The baseline engine is turbocharged with a 
variable geometry turbocharger. The following discussion of 
technologies describes improvements over the 2010 model year baseline 
engine performance, unless otherwise noted. Further discussion of the 
baseline engine and its performance can be found in Section III.A.2.6 
below.
    With respect to stringency level, the agencies received comments 
from Cummins and Daimler stating that the proposed stringency levels 
were appropriate for the lead-times. Conversely, the agencies received 
comments from several environmental groups (UCS, CATF, ACEEE) 
supporting a greater reduction in engine CO2 emissions and 
fuel consumption based on the NAS report. Navistar also stated that the 
agencies' baseline engine is inappropriate since there is not currently 
a 0.20 NOX compliant engine in production. A discussion of 
how the baseline engine configuration can be found below in Section 
(2)(b)(i).
    Navistar also stated that the baseline engines proposed in the 
NPRM, MY 2010 selective catalytic reduction (SCR)-equipped, could not 
meet the agencies' statutory obligation to set feasible standards, and 
requested instead that MY 2010 engines currently in-use be used to meet 
the feasibility factor. The agencies thus disagree with the statement 
that SCR is infeasible and therefore, the agencies reaffirm that the 
engine used as the baseline engine in the agencies' analysis does 
indeed exist. In fact, several engine families have been certified by 
EPA using SCR technology over the past two years, all of which have met 
the 0.20 g/bhp-hr NOX standard.\214\ EPA disagrees with 
Navistar that SCR engines currently certified do not meet this 
standard. Compliance with the 0.20 g/bhp-hr FTP NOX standard 
is measured based on an engine's performance when tested over a 
specific duty cycle (see 40 CFR 86.007-11(a)(2)). This is also true 
regarding the SET standard (see 40 CFR 86.007-11(a)(3)). Further, the 
FTP and SET tests are average tests, so emissions could go over 0.20 
even for some portion of the test itself. Manufacturers are also 
required to ensure that their engines meet the NTE standard under all 
conditions specified in the regulations (see 40 CFR 86.007-11(a)(4)).
---------------------------------------------------------------------------

    \214\ See 2010 Model Year Engine Certification Data and 2011 
Model Year Engine Certification Data files located in the Docket 
EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    Several manufacturers have been able to show compliance with these 
standards in applications for certification provided to EPA for several 
engine families. Navistar has provided no information indicating that 
these tests were false or improper. Indeed, Navistar does not appear to 
suggest, or provide any evidence, that engines with working SCR systems 
do not meet the NOX standard. Thus, it is demonstrably false 
to conclude that the NOX standard cannot be met with SCR-
equipped engines.
    A more detailed response to these comments appears in Section 6.2 
of the Response to Comment document for this rule.
    Engine performance for CO2 emissions and fuel 
consumption can be improved by use of the following technologies:
    Improved Combustion Process: Fuel consumption reductions in the 
range of 1 to 3 percent over the baseline diesel engine are identified 
in the 2010 NAS report through improved combustion chamber design, 
higher fuel injection pressure, improved injection shaping and timing, 
and higher peak cylinder pressures.\215\
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    \215\ See TIAX. Note 198, Page 4-13.
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    Turbochargers: Improved efficiency of a turbocharger compressor or 
turbine could reduce fuel consumption by approximately 1 to 2 percent 
over variable geometry turbochargers in the market today.\216\ The 2010 
NAS report identified technologies such as higher pressure ratio radial 
compressors, axial compressors, and dual stage turbochargers as design 
paths to improve turbocharger efficiency.
---------------------------------------------------------------------------

    \216\ See TIAX Note 198, Page 4-2.
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    Higher efficiency air handling processes: To maximize the 
efficiency of such processes, induction systems may be improved by 
manufacturing more efficiently designed flow paths (including those 
associated with air cleaners, chambers, conduit, mass air flow sensors 
and intake manifolds) and by designing such systems for improved 
thermal control. Improved turbocharging and air handling systems must 
include higher efficiency EGR systems and intercoolers that reduce 
frictional pressure loss while maximizing the ability to thermally 
control induction air and EGR. The agencies received comments from 
Honeywell confirming that turbochargers provide a role in reducing the 
CO2 emissions from engines. Other components that offer 
opportunities for improved flow efficiency include cylinder heads, 
ports and exhaust manifolds to further reduce pumping losses. Variable 
air breathing systems such as variable valve actuation may provide 
additional gains at different loads and speeds. The NESCCAF/ICCT study 
indicated up to 1.2 percent reduction could be achieved solely through 
improved EGR systems.
    Low Temperature Exhaust Gas Recirculation: Most medium- and heavy-
duty vehicle diesel engines sold in the U.S. market today use cooled 
EGR, in which part of the exhaust gas is routed through a cooler 
(rejecting energy to the engine coolant) before being returned to the 
engine intake manifold. EGR is a technology employed to reduce peak 
combustion temperatures and thus NOX. Low-temperature EGR 
uses a larger or secondary EGR cooler to achieve lower intake charge 
temperatures, which tend to further reduce NOX formation. If 
the NOX requirement is unchanged, low-temperature EGR can 
allow changes such as more advanced injection timing that will increase 
engine efficiency slightly more than 1 percent.\217\ Because low-
temperature EGR reduces the engine's exhaust temperature, it may not be 
compatible with exhaust energy recovery systems such as 
turbocompounding or a bottoming cycle.
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    \217\ See TIAX, Note 198, Page 4-13.
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    Engine Friction Reduction: Reduced friction in bearings, valve 
trains, and the piston-to-liner interface will improve efficiency. Any 
friction reduction must be carefully developed to avoid issues with 
durability or performance capability. Estimates of fuel consumption 
improvements due to reduced friction range from 0 to 2 percent.\218\
---------------------------------------------------------------------------

    \218\ TIAX, Note 198, pg 4-15
---------------------------------------------------------------------------

    Reduced Parasitic Loads: Accessories that are traditionally gear or 
belt driven by a vehicle's engine can be optimized and/or converted to 
electric power. Examples include the engine water pump, oil pump, fuel 
injection pump, air compressor, power-steering pump, cooling fans, and 
the vehicle's air-conditioning system. Optimization and improved 
pressure regulation may significantly reduce the parasitic load of the 
water, air and fuel pumps. Electrification may result in a reduction in 
power demand, because electrically powered accessories (such as the air 
compressor or power steering) operate only when needed if they are 
electrically powered, but they impose a parasitic demand all the time 
if they are engine driven. In other cases, such as

[[Page 57205]]

cooling fans or an engine's water pump, electric power allows the 
accessory to run at speeds independent of engine speed, which can 
reduce power consumption. The TIAX study used 2 to 4 percent fuel 
consumption improvement for accessory electrification, with the 
understanding that electrification of accessories will have more effect 
in short-haul/urban applications and less benefit in line-haul 
applications.\219\ Bendix, in their comments to the agencies, confirmed 
that there are engine accessories available that can improve an 
engine's fuel efficiency.
---------------------------------------------------------------------------

    \219\ See TIAX. Note 198, Page 3-5.
---------------------------------------------------------------------------

    Selective catalytic reduction: This technology is common on 2010 
the medium- and heavy-duty diesel engines used in Class 7 and 8 
tractors (and the agencies therefore have included it as part of the 
baseline engine, as noted above). Because SCR is a highly effective 
NOX aftertreatment approach, it enables engines to be 
optimized to maximize fuel efficiency, rather than minimize engine-out 
NOX. 2010 SCR systems are estimated to result in improved 
engine efficiency of approximately 3 to 5 percent compared to a 2007 
in-cylinder EGR-based emissions system and by an even greater 
percentage compared to 2010 in-cylinder approaches.\220\ As more 
effective low-temperature catalysts are developed, the NOX 
conversion efficiency of the SCR system will increase. Next-generation 
SCR systems could then enable additional efficiency improvements; 
alternatively, these advances could be used to maintain efficiency 
while down-sizing the aftertreatment. We estimate that continued 
optimization of the catalyst could offer 1 to 2 percent reduction in 
fuel use over 2010 model year systems in the 2014 model year.\221\ The 
agencies estimate an additional 1 to 2 percent reduction may be 
feasible in the 2017 model year through additional refinement.
---------------------------------------------------------------------------

    \220\ Stanton, D. ``Advanced Diesel Engine Technology 
Development for High Efficiency, Clean Combustion.'' Cummins, Inc. 
Annual Progress Report 2008 Vehicle Technologies Program: Advanced 
Combustion Engine Technologies, U.S. Department of Energy. Pp 113-
116. December 2008.
    \221\ See TIAX, Note 198, pg. 4-9.
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    Mechanical Turbocompounding: Mechanical turbocompounding adds a low 
pressure power turbine to the exhaust stream in order to extract 
additional energy, which is then delivered to the crankshaft. Published 
information on the fuel consumption reduction from mechanical 
turbocompounding varies between 2.5 and 5 percent.\222\ Some of these 
differences may depend on the operating condition or duty cycle that 
was considered by the different researchers. The performance of a 
turbocompounding system tends to be highest at full load and much less 
or even zero at light load.
---------------------------------------------------------------------------

    \222\ NESCCAF/ICCT study (p. 54) and TIAX (2009, pp. 3-5).
---------------------------------------------------------------------------

    Electric Turbocompounding: This approach is similar in concept to 
mechanical turbocompounding, except that the power turbine drives an 
electrical generator. The electricity produced can be used to power an 
electrical motor supplementing the engine output, to power electrified 
accessories, or to charge a hybrid system battery. None of these 
systems have been demonstrated commercially, but modeled results by 
industry and DOE have shown improvements of 3 to 5 percent.\223\
---------------------------------------------------------------------------

    \223\ K. G. Duleep of Energy and Environmental Analysis, R. 
Kruiswyk, 2008, pp. 212-214, NESCCAF/ICCT, 2009, p. 54.
---------------------------------------------------------------------------

    Bottoming Cycle: An engine with bottoming cycle uses exhaust or 
other heat energy from the engine to create power without the use of 
additional fuel. The sources of energy include the exhaust, EGR, charge 
air, and coolant. The estimates for fuel consumption reduction range up 
to 10 percent as documented in the 2010 NAS report.\224\ However, none 
of the bottoming cycle or Rankine systems has been demonstrated 
commercially and are currently in only the research stage. See Section 
2.4.2.7 of the RIA and Section II.B above.
---------------------------------------------------------------------------

    \224\ See 2010 NAS Report, Note 197, page 57.
---------------------------------------------------------------------------

(2) Projected Technology Package Effectiveness and Cost
(a) Class 7 and 8 Combination Tractors
    EPA and NHTSA project that CO2 emissions and fuel 
consumption reductions can be feasibly and cost-effectively achieved in 
these rules' time frames through the increased application of 
aerodynamic technologies, LRR tires, weight reduction, extended idle 
reduction technologies, vehicle speed limiters, and engine 
improvements. The agencies believe that hybrid powertrains systems for 
tractors will not be sufficiently developed and the necessary 
manufacturing capacity put in place to base a standard on any 
significant volume of hybrid tractors. The agencies are not aware of 
any full hybrid systems currently developed for long haul tractor 
applications. To date, hybrid systems for tractors have been primarily 
focused on idle shutdown technologies and not the broader energy 
storage and recovery systems necessary to achieve reductions over 
typical vehicle drive cycles. The final standards reflect the potential 
for idle shutdown technologies through the GEM model. Further as 
highlighted by the 2010 NAS report, the agencies do believe that full 
hybrid powertrains have the potential in the longer term to provide 
significant improvements in fuel efficiency and to reduce greenhouse 
gas emissions. However lacking any existing systems or manufacturing 
base, we cannot conclude such technology will be available in the 2014-
2018 timeframe. Developing a full hybrid system itself would be a three 
to five project followed by several more years to put in place 
manufacturing capacity. The agencies are including incentives for the 
use of hybrid technologies to help encourage their development and to 
reward manufacturers that can produce hybrids through prototype and low 
volume production methods. The agencies also are not including 
drivetrain technologies in the standard setting process, as discussed 
in Section II.B.3.h.iv.
    The agencies evaluated each technology and estimated the most 
appropriate application rate of technology into each tractor 
subcategory. The next sections describe the effectiveness of the 
individual technologies, the costs of the technologies, the projected 
application rates of the technologies into the regulatory 
subcategories, and finally the derivation of the final standards.
(i) Baseline Tractor Performance
    The agencies developed the baseline tractor for each subcategory to 
represent an average 2010 model year tractor configured as noted 
earlier. The approach taken by the agencies was to define the 
individual inputs to the GEM, as shown in Table III-1. For example, the 
agencies evaluated the industry's tractor offerings and concluded that 
the average tractor contains a generally aerodynamic shape (such as 
roof fairings) and avoids classic features such as an exhaust stacks at 
the B-pillar, which increases drag. As noted earlier, our assessment of 
the baseline new high roof tractor fleet aerodynamics consists of 
approximately 25 percent Bin I, 70 percent Bin II, and 5 percent Bin 
III tractors. The baseline rolling resistance coefficient for today's 
fleet is 7.8 kg/metric ton for the steer tire and 8.2 kg/metric ton for 
the drive tire, based on sales weighting of the top three

[[Page 57206]]

manufacturers based on market share.\225\ The agencies assumed no 
application of vehicle speed limiters, weight reduction technologies, 
or idle reduction technologies in the baseline tractor. The agencies 
use the inputs in the GEM to derive the baseline CO2 
emissions and fuel consumption of Class 7 and 8 tractors. The results 
are included in Table III-1.
---------------------------------------------------------------------------

    \225\ U.S. Environmental Protection Agency. SmartWay Transport 
Partnership July 2010 e-update accessed July 16, 2010, from http://www.epa.gov/smartwaylogistics/newsroom/documents/e-update-july-10.pdf.

                                                        Table III-1--Baseline Tractor Definitions
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Class 7                                                    Class 8
                                    --------------------------------------------------------------------------------------------------------------------
                                                    Day cab                                Day cab                              Sleeper cab
                                    --------------------------------------------------------------------------------------------------------------------
                                       Low roof     Mid roof    High roof     Low roof     Mid roof    High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Aerodynamics (Cd)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................         0.77         0.87         0.73         0.77         0.87         0.73         0.77         0.87         0.70
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Steer Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................          7.8          7.8          7.8          7.8          7.8          7.8          7.8          7.8          7.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Drive Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................          8.2          8.2          8.2          8.2          8.2          8.2          8.2          8.2          8.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Weight Reduction (lb)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................            0            0            0            0            0            0            0            0            0
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Extended Idle Reduction (gram CO2/ton-mile reduction)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................          N/A          N/A          N/A          N/A          N/A          N/A            0            0            0
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Vehicle Speed Limiter
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................  ...........  ...........  ...........  ...........  ...........  ...........  ...........  ...........  ...........
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Engine
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline...........................  2010 MY 11L  2010 MY 11L  2010 MY 11L  2010 MY 15L  2010 MY 15L  2010 MY 15L  2010 MY 15L  2010 MY 15L  2010 MY 15L
                                          Engine       Engine       Engine       Engine       Engine       Engine       Engine       Engine       Engine
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                     Table III-2--Class 7 and 8 Tractor Baseline CO2 Emissions and Fuel Consumption
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Class 7                                                    Class 8
                                    --------------------------------------------------------------------------------------------------------------------
                                                    Day cab                                Day cab                              Sleeper cab
                                    --------------------------------------------------------------------------------------------------------------------
                                       Low roof     Mid roof    High roof     Low roof     Mid roof    High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
CO2 (grams CO2/ton-mile)...........          116          128          138           88           95          103           80           89           94
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fuel Consumption (gal/1,000 ton-            11.4         12.6         13.6          8.7          9.4         10.1          7.8          8.7          9.3
 mile).............................
--------------------------------------------------------------------------------------------------------------------------------------------------------

(ii) Tractor Technology Package Definitions
    The agencies' assessment of the final technology effectiveness was 
developed through the use of the GEM in coordination with chassis 
testing of three SmartWay certified Class 8 sleeper cabs. The agencies 
developed the standards through a three-step process. First, the 
agencies developed technology performance characteristics for each 
technology, described below. Each technology is associated with an 
input parameter which is in turn modeled in the GEM. The performance 
levels for the range of Class 7 and 8 tractor aerodynamic packages and 
vehicle technologies are described in Table III-3. Second, the agencies 
combined the technology performance levels with a projected technology 
application rate to determine the GEM inputs used to set the stringency 
of the final standards. Third, the agencies input the parameters

[[Page 57207]]

into GEM and used the output to determine the final CO2 
emissions and fuel consumption levels.
Aerodynamics
    The aerodynamic packages are categorized as Bin I, Bin II, Bin III, 
Bin IV, or Bin V based on the aerodynamic performance determined 
through testing conducted by the manufacturer. A more complete 
description of these aerodynamic packages is included in Chapter 2 of 
the RIA. In general, the CdA values for each package and tractor 
subcategory were developed through EPA's coastdown testing of tractor-
trailer combinations, the 2010 NAS report, and SAE papers.
Tire Rolling Resistance
    The rolling resistance coefficient for the tires was developed from 
SmartWay's tire testing to develop the SmartWay certification, in 
addition to testing a selection of tractor tires as part of this 
program. The tire performance was evaluated in three levels--the 
baseline (average), 15 percent better than the average, and an 
additional 15 percent improvement. The first 15 percent improvement 
represents the threshold used to develop SmartWay certified tires for 
long haul tractors. The second 15 percent threshold represents an 
incremental step for improvements beyond today's SmartWay level and 
represents the best in class rolling resistance of the tires we tested.
Weight Reduction
    The weight reductions were developed from tire manufacturer 
information, the Aluminum Association, the Department of Energy, and 
TIAX, as discussed above in Section II.B.3.e.
Idle Reduction
    The benefits for the extended idle reductions were developed from 
literature, SmartWay work, and the 2010 NAS report. The agencies 
received comments from multiple stakeholders regarding idle reduction 
technologies (IRT). Two commenters asked us to revise the default value 
associated with the IRT technology, and two commenters want to use IRT 
in GEM even without automatic engine shut down (AES). The agencies 
proposed AES after 5 minutes with no exceptions to help ensure that the 
idle reductions are realized in-use. Use of an AES ensures the main 
engine will be shut down, whereas idle reduction technologies alone do 
not provide that level of certainty. Without an automatic shutdown of 
the main engine, actual savings would depend on operator behavior and 
thus be essentially unverifiable. The agencies are finalizing the 
calculation as proposed, along with the automotive engine shutdown 
requirement. Additional details regarding the comments and calculations 
are included in RIA Section 2.5.4.2.
    Several commenters requested that the level of emissions reductions 
vary in GEM by different idle reduction technologies, and one commenter 
requested that the application of battery powered APUs be incentivized. 
The agencies recognize that the level of emission reductions provided 
by different IRT varies, but are adopting a conservative level to 
recognize that some vehicles may be sold with only an AES but may then 
install an IRT in-use. Or some vehicles may be sold with one IRT but 
then choose to install alternative ones in-use. The agencies cannot 
verify the savings which depend on operator behavior.
    One commenter requested that we provide manufacturers with an 
option to allow the AES feature to be reprogammable after a specified 
number of miles or time in service. The agencies recognize that AES may 
impact the resale value of tractors and, in response to comments, are 
adopting provisions for the optional expiration of an AES. Thus, the 
initial buyer could select AES only for the number of miles based on 
the expected time before resale. Similar to vehicle speed limiters, we 
would discount the impact based on the full life of the truck (e.g. 
1,259,000 miles). Additional detail can be found in RIA Section 
2.5.4.2.
Vehicle Speed Limiter
    The agencies are not including vehicle speed limiters in the 
technology package for Class 7 and 8 tractors.
Summary of Technology Performance
    Table III-3 describes the performance levels for the range of Class 
7 and 8 tractor aerodynamic packages and vehicle technologies.

                                                  Table III-3--Class 7 and 8 Tractor Technology Values
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Class 7                                      Class 8
                                                              ------------------------------------------------------------------------------------------
                                                                        Day cab                   Day cab                       Sleeper cab
                                                              ------------------------------------------------------------------------------------------
                                                                 Low/mid                   Low/mid
                                                                   roof      High roof       roof      High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Aerodynamics (Cd)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bin I........................................................    0.77/0.87         0.79    0.77/0.87         0.79         0.77         0.87         0.75
Bin II.......................................................    0.71/0.82         0.72    0.71/0.82         0.72         0.71         0.82         0.68
Bin III......................................................  ...........         0.63  ...........         0.63  ...........  ...........         0.60
Bin IV.......................................................  ...........         0.56  ...........         0.56  ...........  ...........         0.52
Bin V........................................................  ...........         0.51  ...........         0.51  ...........  ...........         0.47
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Steer Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline.....................................................          7.8          7.8          7.8          7.8          7.8          7.8          7.8
Level I......................................................          6.6          6.6          6.6          6.6          6.6          6.6          6.6
Level II.....................................................          5.7          5.7          5.7          5.7          5.7          5.7          5.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Drive Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline.....................................................          8.2          8.2          8.2          8.2          8.2          8.2          8.2
Level I......................................................          7.0          7.0          7.0          7.0          7.0          7.0          7.0
Level II.....................................................          6.0          6.0          6.0          6.0          6.0          6.0          6.0
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 57208]]

 
                                                                  Weight Reduction (lb)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Control......................................................          400          400          400          400          400          400          400
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                Extended Idle Reduction (gram CO2/ton-mile reduction) \a\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Control......................................................          N/A          N/A          N/A          N/A            5            5            5
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Vehicle Speed Limiter \b\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Control......................................................          N/A          N/A          N/A          N/A          N/A          N/A          N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ While the standards are set based on this value, users would enter another value if AES is not applied or applied for less than the full useful life
  of the engine.
\b\ Vehicle speed limiters are an applicable technology for all Class 7 and 8 tractors, however the standards are not premised on the use of this
  technology.

(iii) Tractor Technology Application Rates
    As explained above, vehicle manufacturers often introduce major 
product changes together, as a package. In this manner the 
manufacturers can optimize their available resources, including 
engineering, development, manufacturing and marketing activities to 
create a product with multiple new features. In addition, manufacturers 
recognize that a truck design will need to remain competitive over the 
intended life of the design and meet future regulatory requirements. In 
some limited cases, manufacturers may implement an individual 
technology outside of a vehicle's redesign cycle.
    With respect to the levels of technology application used to 
develop the final standards, NHTSA and EPA established technology 
application constraints. The first type of constraint was established 
based on the application of fuel consumption and CO2 
emission reduction technologies into the different types of tractors. 
For example, idle reduction technologies are limited to Class 8 sleeper 
cabs using the assumption that day cabs are not used for overnight 
hoteling. A second type of constraint was applied to most other 
technologies and limited their application based on factors reflecting 
the real world operating conditions that some combination tractors 
encounter. This second type of constraint was applied to the 
aerodynamic, tire, and vehicle speed limiter technologies. Table III-4 
specifies the application rates that EPA and NHTSA used to develop the 
final standards. The agencies received a significant number of comments 
related to this second basis. In particular, commenters questioned the 
reasons for not requiring the maximum reduction technology in every 
case. The agencies have not done so because we have concluded that 
within each of these individual vehicle categories there are particular 
applications where the use of the identified technologies would be 
either ineffective or not technically feasible. The addition of 
ineffective technologies provides no environmental or fuel efficiency 
benefit, increases costs and is not a basis upon which to set a maximum 
feasible improvement. For example, the agencies have not required the 
use of full aerodynamic vehicle treatments on 100 percent of tractors 
because we know that in many applications (for example gravel truck 
engaged in local aggregate delivery) the added weight of the 
aerodynamic technologies will increase fuel consumption and hence 
CO2 emissions to a greater degree than the reduction that 
would be accomplished from the more aerodynamic nature of the tractor. 
To simply set the standard based on the largest reduction possible 
estimated narrowly over a single test procedure while ignoring the in-
use effects of the technology would in this case result in a perverse 
outcome that is not in keeping with the agencies' goals or the 
requirements of the CAA and EISA.
Aerodynamics Application Rate
    The impact of aerodynamics on a truck's efficiency increases with 
vehicle speed. Therefore, the usage pattern of the truck will determine 
the benefit of various aerodynamic technologies. Sleeper cabs are often 
used in line haul applications and drive the majority of their miles on 
the highway travelling at speeds greater than 55 mph. The industry has 
focused aerodynamic technology development, including SmartWay 
tractors, on these types of trucks. Therefore the agencies are adopting 
the most aggressive aerodynamic technology application to this 
regulatory subcategory. All of the major manufacturers today offer at 
least one SmartWay truck model. The 2010 NAS Report on heavy-duty 
trucks found that manufacturers indicated that aerodynamic improvements 
which yield 3 to 4 percent fuel consumption reduction or 6 to 8 percent 
reduction in Cd values, beyond technologies used in today's SmartWay 
trucks are achievable.\226\ The aerodynamic application rate for Class 
8 sleeper cab high roof cabs (i.e., the degree of technology 
application on which the stringency of the final standard is premised) 
consists of 20 percent of Bin IV, 70 percent Bin III, and 10 percent 
Bin II reflecting our assessment of the fraction of tractors in this 
segment that can successfully apply these aerodynamic packages.
---------------------------------------------------------------------------

    \226\ See TIAX, Note 198, Page 4-40.
---------------------------------------------------------------------------

    The 90 percent of tractors that we project can either be Bin II or 
Bin III equipped reflects the bulk of Class 8 high roof sleeper cab 
applications. We are not projecting a higher fraction of Bin III 
aerodynamic systems because of the limited lead time for the program 
and the need for these more advanced technologies to be developed and 
demonstrated before being applied across a wider fraction of the fleet. 
Aerodynamic improvements through new tractor designs and the

[[Page 57209]]

development of new aerodynamic components is an inherently slow and 
iterative process. Aerodynamic impacts are highly nonlinear and often 
reflect unexpected interactions between multiple components. Given the 
nature of aerodynamic improvements it is inherently difficult to 
estimate the degree to which improvements can be made beyond previously 
demonstrated levels. The changes required for Bins III and IV reflect 
the kinds of improvements projected in the Department of Energy's 
Supertruck program. That program assumes that such systems can be 
demonstrated on vehicles by 2017. In this case, the agencies are 
projecting that truck OEMs will be able to begin implementing these 
aerodynamic technologies prior to 2017 on a limited scale. Importantly, 
our averaging, banking and trading provisions provide manufacturers 
with the flexibility to implement these technologies over time even 
though the standard changes in a single step.
    The final aerodynamic application for the other tractor regulatory 
categories is less aggressive than for the Class 8 sleeper cab high 
roof. The agencies recognize that there are truck applications which 
require on/off-road capability and other truck functions which restrict 
the type of aerodynamic equipment applicable. We also recognize that 
these types of trucks spend less time at highway speeds where 
aerodynamic technologies have the greatest benefit. The 2002 VIUS data 
ranks trucks by major use.\227\ The heavy trucks usage indicates that 
up to 35 percent of the trucks may be used in on/off-road applications 
or heavier applications. The uses include construction (16 percent), 
agriculture (12 percent), waste management (5 percent), and mining (2 
percent). Therefore, the agencies analyzed the technologies to evaluate 
the potential restrictions that would prevent 100 percent application 
of SmartWay technologies for all of the tractor regulatory 
subcategories.
---------------------------------------------------------------------------

    \227\ U.S. Department of Energy. Transportation Energy Data 
Book, Edition 28-2009. Table 5.7.
---------------------------------------------------------------------------

    As discussed in Section II.B.2.c, in response to comments received 
from manufacturers making some of these same points, the agencies are 
finalizing only two aerodynamic bins for low and mid roof tractors. The 
agencies are reducing the number of bins for these tractors from the 
proposal to reflect the actual range of aerodynamic technologies 
effective in low and mid roof tractor applications. The aerodynamic 
improvements to the bumper, hood, windshield, mirrors, and doors are 
developed for the high roof tractor application and then carried over 
into the low and mid roof applications. As mentioned in Section 
II.B.2.c, the types of designs that would move high roof tractors from 
a Bin III to Bins IV and V include features such as gap reducers and 
integral roof fairings which would not be appropriate on low and mid 
roof tractors. Thus, the agencies are differentiating the aerodynamic 
performance for low- and mid-roof tractors into two bins--Bin I and Bin 
II. The application rates in the low and mid roof categories are the 
same as proposed, but aggregated into just two bins. Bin I for these 
tractors corresponds to the proposed ``Classic'' and ``Conventional'' 
bins and Bin II corresponds to the proposed ``SmartWay,'' ``Advanced 
SmartWay,'' and ``Advanced SmartWay II'' bins.
Low Rolling Resistance Tire Application Rate
    At proposal, the agencies stated that at least one LRR tire model 
is available today that meets the rolling resistance requirements of 
the Level I and Level II tire packages so the 2014 MY should afford 
manufacturers sufficient lead time to install these packages. EPA and 
NHTSA conducted additional evaluation testing on HD tires used for 
tractors. The agencies also received several comments on the 
suitability of low rolling resistance tires for various HD truck 
applications. The summary of the agencies findings and a response to 
issues raised by commenters is presented in Section II.D(1)(a).
    The agencies note that baseline rolling resistance level for tires 
installed on tractors is approximately equivalent to what the agencies 
consider to be low rolling resistance tires for vocational vehicles 
because of the tire manufacturer's focus on improving the rolling 
resistance of tractor tires. For the tire manufacturers to further 
reduce tire rolling resistance, the manufacturers must consider several 
performance criteria that affect tire selection. The characteristics of 
a tire also influence durability, traction control, vehicle handling, 
comfort, and retreadability. A single performance parameter can easily 
be enhanced, but an optimal balance of all the criteria will require 
improvements in materials and tread design at a higher cost, as 
estimated by the agencies. Tire design requires balancing performance, 
since changes in design may change different performance 
characteristics in opposing directions. Similar to the discussion 
regarding lesser aerodynamic technology application in tractor segments 
other than sleeper cab high roof, the agencies believe that the final 
standards should not be premised on 100 percent application of Level II 
tires in all tractor segments given the interference with vehicle 
utility that would result. The agencies are basing their analyses on 
application rates that vary by subcategory recognizing that some 
subcategories require a different balancing of performance versus 
rolling resistance.
Weight Reduction Technology Application Rate
    The agencies proposed setting the 2014 model year tractor standards 
using 100 percent application of a 400 pound weight reduction package. 
Volvo and ATA stated in their comments that not all fleets can use 
single wide tires and if this is the case the 400 pound weight 
reduction cannot be met. The agencies also received comments from MEMA, 
Navistar, American Chemistry Council, the Auto Policy Center, Iron and 
Steel Institute, Arvin Meritor, Aluminum Association, and environmental 
groups and NGOs identifying other potential weight reduction 
opportunities for tractors. As described in Section II.B.3.e above, the 
agencies are adopting an expanded list of weight reduction options 
which can be input into the GEM for the final rulemaking.
    As also explained in that earlier discussion, the agencies, upon 
further analysis, continue to believe that a 400 pound weight reduction 
package is appropriate for tractors in the time frame. As stated in 
Section II.B.2.e above, for tractors where single wide tires are not 
appropriate, the manufacturers have additional options available to 
achieve weight reduction, such as body panels and chassis components as 
documented in the earlier discussion. The agencies have extended the 
list of weight reduction components in order to provide the 
manufacturers with additional means to comply with the combination 
tractors and to further encourage reductions in vehicle weight. The 
agencies considered increasing the target value beyond 400 pounds given 
the additional reduction potential components identified in the 
expanded list; however, lacking information on the capacity for the 
industry to change to these light weight components across the board by 
the 2014 model year, we have decided to maintain the 400 pound target. 
The agencies intend to continue to study the potential for additional 
weight reductions in our future work considering a second phase of 
truck fuel efficiency and GHG regulations.

[[Page 57210]]

Idle Reduction Technology Application Rate
    Idle reduction technologies provide significant reductions in fuel 
consumption and CO2 emissions for Class 8 sleeper cabs and 
are available on the market today, and therefore will be available in 
the 2014 model year. There are several different technologies available 
to reduce idling. These include APUs, diesel fired heaters, and battery 
powered units. Our discussions with manufacturers indicate that idle 
technologies are sometimes installed in the factory, but it is also a 
common practice to have the units installed after the sale of the 
truck. We would like to continue to incentivize this practice and to do 
so in a manner that the emission reductions associated with idle 
reduction technology occur in use. Therefore, as proposed, we are 
allowing only idle emission reduction technologies with include an 
automatic engine shutoff (AES). We are also adopting some override 
provisions in response to comments we received (as explained below). As 
proposed, we are adopting a 100 percent application rate for this 
technology for Class 8 sleeper cabs, even though the current fleet is 
estimated to have a 30 percent application rate. The agencies are 
unaware of reasons why AES with extended idle reduction technologies 
could not be applied to all tractors with a sleeper cab, except those 
deemed a vocational tractor, in the available lead time.
    One commenter stated the application rate of AES should be less 
than 100 percent, but did not recommend an alternative application rate 
or provide justification for a change. The agencies re-evaluated the 
proposed 100 percent application rate and determined that a 100 percent 
application rate for this technology for Class 8 sleeper cabs remains 
appropriate. The agencies have also considered the many comments which 
raised concerns about the proposed mandatory 5 minute automatic engine 
shut down without override capability (in terms of safety, extreme 
temperatures and low battery conditions). To avoid unintended adverse 
impacts, we are adopting limited override provisions. Three of the five 
exceptions are similar to those currently in effect under a California 
Air Resources Board (CARB) regulation. CARB provides AES exceptions (or 
overrides) within its existing heavy-duty vehicle anti-idling laws, 
which were developed to address these same types of concerns. The 
exceptions we are adopting include override capability during exhaust 
emissions control device regeneration, during engine servicing and 
maintenance, when battery state of charge is too low, in extreme 
ambient temperatures, when engine coolant temperature is too low, and 
during PTO operation. The RIA provides more detail about these final 
override provisions in Section 2.5.4.3.
    The agencies received comment that we should extend the idle 
reduction benefits beyond Class 8 sleepers, including Class 7 tractors 
and vocational vehicles. The agencies reviewed literature to quantify 
the amount of idling which is conducted outside of hoteling operations. 
One study, conducted by Argonne National Laboratory, identified several 
different types of trucks which might idle for extended amounts of time 
during the work day.\228\ Idling may occur during the delivery process, 
queuing at loading docks or border crossings, during power take off 
operations, or to provide comfort during the work day. However, the 
study provided only ``rough estimates'' of the idle time and energy use 
for these vehicles. The agencies are not able to appropriately develop 
a baseline of workday idling for the other types of vehicles and 
identify the percent of this idling which could be reduced through the 
use of AES. Absent such information, the agencies cannot justify adding 
substantial cost for AES systems with such uncertain benefits.
---------------------------------------------------------------------------

    \228\ Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use 
by Idling Commercial Trucks. January 2006.
---------------------------------------------------------------------------

Vehicle Speed Limiter Application Rate
    Vehicle speed limiters may be used as a technology to meet the 
standard, but in setting the standard we assumed a zero percent 
application rate of vehicle speed limiters. Although we believe vehicle 
speed limiters are a simple, easy to implement, and inexpensive 
technology, we want to leave the use of vehicles speed limiters to the 
truck purchaser. Since truck fleets purchase trucks today with owner 
set vehicle speed limiters, we considered not including VSLs in our 
compliance model. However, we have concluded that we should allow the 
use of VSLs that cannot be overridden by the operator as a means of 
compliance for vehicle manufacturers that wish to offer it and truck 
purchasers that wish to purchase the technology. In doing so, we are 
providing another means of meeting that standard that can lower 
compliance cost and provide a more optimal vehicle solution for some 
truck fleets. For example, a local beverage distributor may operate 
trucks in a distribution network of primarily local roads. Under those 
conditions, aerodynamic fairings used to reduce aerodynamic drag 
provide little benefit due to the low vehicle speed while adding 
additional mass to the vehicle. A vehicle manufacturer could choose to 
install a VSL set a 55 mph for this customer. The resulting truck 
modeled in GEM could meet our final emission standard without the use 
of any specialized aerodynamic fairings. The resulting truck would be 
optimized for its intended application and would be fully compliant 
with our program all at a lower cost to the ultimate truck 
purchaser.\229\
---------------------------------------------------------------------------

    \229\ Ibid.
    The agencies note that because a VSL value can be input into 
GEM, its benefits can be directly assessed with the model and off 
cycle credit applications therefore are not necessary even though 
the standard is not based on performance of VSLs (i.e. VSL is an on-
cycle technology).
---------------------------------------------------------------------------

    As discussed in Section II.B.2.g above, we have chosen not to base 
the standards on performance of VSLs because of concerns about how to 
set a realistic application rate that avoids unintended adverse 
impacts. Although we expect there will be some use of VSL, currently it 
is used when the fleet involved decides it is feasible and practicable 
and increases the overall efficiency of the freight system for that 
fleet operator. However, at this point the agencies are not in a 
position to determine in how many additional situations use of a VSL 
would result in similar benefits to overall efficiency. Therefore, the 
agencies are not premising the final standards on use of VSL, and 
instead will rely on the industry to select VSL when circumstances are 
appropriate for its use. The agencies have not included either the cost 
or benefit due to VSLs in analysis of the program's costs and benefits. 
Implementation of this program may provide greater information for 
using this technology in standard setting in the future. Many 
stakeholders including the American Trucking Association have advocated 
for more widespread use of vehicle speed limits to address fuel 
efficiency and greenhouse gas emissions. The Center for Biological 
Diversity (CBD) argued the agencies should reflect the use of VSLs in 
setting the standard for tractors rather than assuming no VSL use in 
determining the appropriate standard. The agencies have chosen not to 
do so because, as explained, we are not able at this time to quantify 
to potential loss in utility due to the use of VSLs. Absent this 
information, we cannot make a determination regarding the 
reasonableness of setting a standard based on a particular VSL level. 
In

[[Page 57211]]

confirmation, a number of commenters most notably the Owner Operator 
Independent Drivers Association (OOIDA) suggest that VSLs could 
significantly impact the ability of a vehicle to deliver goods against 
a fixed schedule and hence would significantly impact its utility. ATA 
commented that limited flexibility must be built into speed limiters as 
not to interfere with NHTSA planned rulemaking in response to 2006 ATA 
petition and its 2008 Sustainability Plan. Similar comments were 
received from DTNA requesting that the agencies consider any NHTSA 
safety regulations that may also be regulating VSLs. NHTSA plans to 
issue a rule in 2012 addressing the safety performance features of 
VSLs.
    Table III-4 provides the final application rates of each technology 
broken down by weight class, cab configuration, and roof height.

                                       Table III-4--Final Technology Application Rates for Class 7 and 8 Tractors
                                                                      [In percent]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Class 7                                      Class 8
                                                              ------------------------------------------------------------------------------------------
                                                                        Day cab                   Day cab                       Sleeper cab
                                                              ------------------------------------------------------------------------------------------
                                                                 Low/mid                   Low/mid
                                                                   roof      High roof       roof      High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Aerodynamics (Cd)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bin I........................................................           40            0           40            0           30           30            0
Bin II.......................................................           60           30           60           30           70           70           10
Bin III......................................................  ...........           60  ...........           60  ...........  ...........           70
Bin IV.......................................................  ...........           10  ...........           10  ...........  ...........           20
Bin V........................................................  ...........            0  ...........            0  ...........  ...........            0
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Steer Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline.....................................................           40           30           40           30           30           30           10
Bin I........................................................           50           60           50           60           60           60           70
Bin II.......................................................           10           10           10           10           10           10           20
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Drive Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Baseline.....................................................           40           30           40           30           30           30           10
Bin I........................................................           50           60           50           60           60           60           70
Bin II.......................................................           10           10           10           10           10           10           20
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Weight Reduction (lb)
--------------------------------------------------------------------------------------------------------------------------------------------------------
400 lb. Weight Reduction.....................................          100          100          100          100          100          100          100
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Extended Idle Reduction (gram CO2/ton-mile reduction)
--------------------------------------------------------------------------------------------------------------------------------------------------------
AES..........................................................          N/A          N/A          N/A          N/A          100          100          100
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Vehicle Speed Limiter
--------------------------------------------------------------------------------------------------------------------------------------------------------
VSL..........................................................            0            0            0            0            0            0            0
--------------------------------------------------------------------------------------------------------------------------------------------------------

(iv) Derivation of the Final Tractor Standards
    The agencies used the technology inputs and final technology 
application rates in GEM to develop the final fuel consumption and 
CO2 emissions standards for each subcategory of Class 7 and 
8 combination tractors. The agencies derived a scenario tractor for 
each subcategory by weighting the individual GEM input parameters 
included in Table III-3 with the application rates in Table III-4. For 
example, the Cd value for a Class 8 Sleeper Cab High Roof scenario case 
was derived as 10 percent times 0.68 plus 70 percent times 0.60 plus 20 
percent times 0.55, which is equal to a Cd of 0.60. Similar 
calculations were done for tire rolling resistance, weight reduction, 
idle reduction, and vehicle speed limiters. To account for the two 
final engine standards, the agencies assumed a compliant engine in 
GEM.\230\ In other words, EPA is finalizing the use of a 2014 model 
year fuel consumption map in GEM to derive the 2014 model year tractor 
standard and a 2017 model year fuel consumption map to derive the 2017 
model year tractor standard.\231\ The agencies then ran GEM with a 
single set of vehicle inputs, as shown in Table III-5, to derive the 
final standards for each subcategory. Additional detail is provided in 
the RIA Chapter 2.
---------------------------------------------------------------------------

    \230\ See Section III.A.2.b below explaining the derivation of 
the engine standards.
    \231\ As explained further in Section V below, EPA would use 
these inputs in GEM even for engines electing to use the alternative 
engine standard.

[[Page 57212]]

                                         Table III-5--GEM Inputs for the Class 7 and 8 Tractor Standard Setting
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                  Class 7                                                                      Class 8
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                  Day cab                                                  Day cab                              Sleeper cab
--------------------------------------------------------------------------------------------------------------------------------------------------------
                    Low roof                        Mid roof    High roof     Low roof     Mid roof    High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Aerodynamics (Cd)
--------------------------------------------------------------------------------------------------------------------------------------------------------
0.73............................................         0.84         0.65         0.73         0.84         0.65         0.73         0.84         0.59
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Steer Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
6.99............................................         6.99         6.87         6.99         6.99         6.87         6.87         6.87         6.54
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Drive Tires (CRR kg/metric ton)
--------------------------------------------------------------------------------------------------------------------------------------------------------
7.38............................................         7.38         7.26         7.38         7.38         7.26         7.26         7.26         6.92
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Weight Reduction (lb)
--------------------------------------------------------------------------------------------------------------------------------------------------------
400.............................................          400          400          400          400          400          400          400          400
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Extended Idle Reduction (gram CO2/ton-mile reduction)
--------------------------------------------------------------------------------------------------------------------------------------------------------
N/A.............................................          N/A          N/A          N/A          N/A          N/A            5            5            5
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Vehicle Speed Limiter
--------------------------------------------------------------------------------------------------------------------------------------------------------
--..............................................  ...........  ...........  ...........  ...........  ...........  ...........  ...........  ...........
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Engine
--------------------------------------------------------------------------------------------------------------------------------------------------------
2014/17 MY 11L Engine...........................   2014/17 MY   2014/17 MY   2014/17 MY   2014/17 MY   2014/17 MY   2014/17 MY   2014/17 MY   2014/17 MY
                                                   11L Engine   11L Engine   15L Engine   15L Engine   15L Engine   15L Engine   15L Engine   15L Engine
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The level of the 2014 and 2017 model year final standards and 
percent reduction from the baseline for each subcategory are included 
in Table III-6.

                         Table III-6--Final 2014 and 2017 Model Year Tractor Reductions
----------------------------------------------------------------------------------------------------------------
 
----------------------------------------------------------------------------------------------------------------
                                     2014 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
                                                                              Day cab                Sleeper cab
                                                                 -----------------------------------------------
                                                                          Class 7         Class 8         Class
                                                                 -----------------------------------------------
Low Roof........................................................             107              81              68
Mid Roof........................................................             119              88              76
High Roof.......................................................             124              92              75
----------------------------------------------------------------------------------------------------------------
2014-2016 Model Year Gallons of Fuel per 1,000 Ton-Mile \232\
----------------------------------------------------------------------------------------------------------------
                                                                              Day cab                 Sleeper cab
                                                                 -----------------------------------------------
                                                                          Class 7         Class 8         Class
                                                                 -----------------------------------------------
Low Roof........................................................            10.5             8.0             6.7
Mid Roof........................................................            11.7             8.7             7.4
High Roof.......................................................            12.2             9.0             7.3
----------------------------------------------------------------------------------------------------------------
2017 Model Year CO2 Grams per Ton-Mile
----------------------------------------------------------------------------------------------------------------
                                                                              Day cab                 Sleeper cab
                                                                 -----------------------------------------------
                                                                          Class 7         Class 8         Class
                                                                 -----------------------------------------------
Low Roof........................................................             104              80              66
Mid Roof........................................................             115              86              73
High Roof.......................................................             120              89              72
----------------------------------------------------------------------------------------------------------------
2017 Model Year and Later Gallons of Fuel per 1,000 Ton-Mile
----------------------------------------------------------------------------------------------------------------

[[Page 57213]]

 
                                                                              Day cab                 Sleeper cab
                                                                 -----------------------------------------------
                                                                          Class 7         Class 8         Class
                                                                 -----------------------------------------------
Low Roof........................................................            10.2             7.8             6.5
Mid Roof........................................................            11.3             8.4             7.2
High Roof.......................................................            11.8             8.7             7.1
----------------------------------------------------------------------------------------------------------------

    A summary of the final technology package costs is included in 
Table III-7 with additional details available in the RIA Chapter 2.
---------------------------------------------------------------------------

    \232\ Manufacturers may voluntarily opt-in to the NHTSA fuel 
consumption program in 2014 or 2015. If a manufacturer opts-in, the 
program becomes mandatory.

                 Table III-7--Class 7 and 8 Tractor Technology Costs Inclusive of Indirect Cost Markups in the 2014 Model Year a (2009$)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Class 7                                      Class 8
                                                              ------------------------------------------------------------------------------------------
                                                                        Day cab                   Day cab                       Sleeper cab
                                                              ------------------------------------------------------------------------------------------
                                                                 Low/mid                   Low/mid
                                                                   roof      High roof       roof      High roof     Low roof     Mid roof    High roof
--------------------------------------------------------------------------------------------------------------------------------------------------------
Aerodynamics.................................................         $675         $924         $675         $924         $962         $983       $1,627
Steer Tires..................................................           68           68           68           68           68           68           68
Drive Tires..................................................           63           63          126          126          126          126          126
Weight Reduction.............................................        1,536        1,536        1,980        1,980        3,275        3,275        1,980
Idle Reduction with Auxiliary Power Unit.....................  ...........  ...........  ...........  ...........        3,819        3,819        3,819
Air Conditioning\c\..........................................           22           22           22           22           22           22           22
                                                              ------------------------------------------------------------------------------------------
    Total....................................................        2,364        2,612        2,871        3,119        8,271        8,291        7,641
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Costs shown are for the 2014 model year so do not reflect learning impacts which would result in lower costs for later model years. For a
  description of the learning impacts considered in this analysis and how it impacts technology costs for other years, refer to Chapter 2 of the RIA
  (see RIA 2.2.2).
\b\ Note that values in this table include penetration rates. Therefore, the technology costs shown reflect the average cost expected for each of the
  indicated classes. To see the actual estimated technology costs exclusive of penetration rates, refer to Chapter 2 of the RIA (see RIA 2.9 in
  particular).
\c\ EPA's air conditioning standards are presented in Section II.E.5 above.

(v) Reasonableness of the Final Standards
    The final standards are based on aggressive application rates for 
control technologies which the agencies regard as the maximum feasible 
for purposes of EISA section 32902 (k) and appropriate under CAA 
section 202 (a) for the reasons given in Section (iii) above; see also 
RIA Chapter 2.5.8.2. These technologies, at the estimated application 
rates, are available within the lead time provided, as discussed in RIA 
Chapter 2.5. Use of these technologies would add only a small amount to 
the cost of the vehicle, and the associated reductions are highly cost 
effective, an estimated $20 per ton of CO2eq per vehicle in 
2030 without consideration of the substantial fuel savings.\233\ This 
is even more cost effective than the estimated cost effectiveness for 
CO2eq removal and fuel economy improvements under the light-
duty vehicle rule, already considered by the agencies to be a highly 
cost effective reduction.\234\ Moreover, the cost of controls is 
rapidly recovered due to the associated fuel savings, as shown in the 
payback analysis included in Table VIII-11 located in Section VIII 
below. Thus, overall cost per ton of the program, considering fuel 
savings, is negative--fuel savings associated with the rules more than 
offset projected costs by a wide margin. See Table VIII-6 in Section 
VIII below. Given that the standards are technically feasible within 
the lead time afforded by the 2014 model year, are inexpensive and 
highly cost effective even without accounting for the fuel savings, and 
have no apparent adverse potential impacts (e.g., there are no 
projected negative impacts on safety or vehicle utility), the final 
standards represent a reasonable choice under section 202(a) of the CAA 
and the maximum feasible under NHTSA's EISA authority at 49 U.S.C. 
32902(k)(2).
---------------------------------------------------------------------------

    \233\ See Section VIII.D below.
    \234\ The light-duty rule had an estimated cost per ton of $50 
when considering the vehicle program costs only and a cost of -$210 
per ton considering the vehicle program costs along with fuel 
savings in 2030. See 75 FR 25515, Table III.H.3-1.
---------------------------------------------------------------------------

(vi) Alternative Tractor Standards Considered
    The agencies are not adopting tractor standards less stringent than 
the proposed standards because the agencies believe these standards are 
appropriate, highly cost effective, and technologically feasible within 
the rulemaking time frame.
    The agencies considered adopting tractor standards which are more 
stringent than those proposed reflecting increased application rates of 
the technologies discussed. We also considered setting more stringent 
standards based on the inclusion of hybrid powertrains in tractors. We 
stopped short of finalizing more stringent standards based on higher 
application rates of improved aerodynamic controls and tire rolling 
resistance because we concluded that the technologies would not be 
compatible with the use profile of a subset of tractors which operate 
in off-

[[Page 57214]]

road conditions. We have not adopted more stringent standards for 
tractors based on the use of hybrid vehicle technologies, believing 
that additional development and therefore lead-time is needed to 
develop hybrid systems and battery technology for tractors that operate 
primarily in highway cruise operations. We know, for example, that 
hybrid systems are being researched to capture and return energy for 
tractors that operate in gently rolling hills. However, as discussed 
above, it is not clear to us today that these systems will be generally 
applicable to tractors in the time frame of this regulation. In 
addition, even if hybrid technologies were generally available for 
these tractors during the MY 2014-2017 period, their costs would be 
extremely high and benefits would be limited given that idle reduction 
controls already capture many of the same emissions. According to the 
2010 NAS Report, hybrid powertrains in tractors have the potential to 
improve fuel consumption by 10 percent, but it displaces the 6 percent 
reduction for idle reduction technologies, for a net improvement of 4 
percent at a cost of $25,000 per vehicle.\235\
---------------------------------------------------------------------------

    \235\ See 2010 NAS Report, Note 197, Page 146.
---------------------------------------------------------------------------

(b) Tractor Engines
(i) Baseline Engine Performance
    As noted above, EPA and NHTSA developed the baseline medium- and 
heavy heavy-duty diesel engine to represent a 2010 model year engine 
compliant with the 0.20 g/bhp-hr NOX standard for on-highway 
heavy-duty engines.
    The agencies developed baseline SET values for medium- and heavy 
heavy-duty diesel engines based on 2009 model year confidential 
manufacturer data and from testing conducted by EPA. The agencies 
adjusted the pre-2010 data to represent 2010 model year engine maps by 
using predefined technologies including SCR and other systems that are 
being used in current 2010 model year production. If an engine utilized 
did not meet the 0.20 g/bhp-hr NOX level, then the 
individual engine's CO2 result was adjusted to accommodate 
aftertreatment strategies that would result in a 0.20 g/bhp-hr 
NOX emission level as described in RIA Chapter 2.4.2.1. The 
engine CO2 results were then sales weighted within each 
regulatory subcategory (i.e., medium heavy-duty diesel or heavy heavy-
duty diesel) to develop an industry average 2010 model year reference 
engine. Although, most of the engines fell within a few percent of this 
baseline at least one engine was more than six percent above this 
average baseline.

     Table III-8--2010 Model Year Baseline Diesel Engine Performance
------------------------------------------------------------------------
                                                               Fuel
                                           CO2 Emissions    consumption
                                            (g/bhp-hr)      (gallon/100
                                                              bhp-hr)
------------------------------------------------------------------------
Medium Heavy-Duty Diesel--SET...........             518            5.09
Heavy Heavy-Duty Diesel--SET............             490            4.81
------------------------------------------------------------------------

(ii) Engine Technology Package Effectiveness
    The MHD and HHD diesel engine technology package for the 2014 model 
year includes engine friction reduction, improved aftertreatment 
effectiveness, improved combustion processes, and low temperature EGR 
system optimization. The agencies considered improvements in parasitic 
and friction losses through piston designs to reduce friction, improved 
lubrication, and improved water pump and oil pump designs to reduce 
parasitic losses. The aftertreatment improvements are available through 
lower backpressure of the systems and optimization of the engine-out 
NOX levels. Improvements to the EGR system and air flow 
through the intake and exhaust systems, along with turbochargers can 
also produce engine efficiency improvements. We note that individual 
technology improvements are not additive due to the interaction of 
technologies. The agencies assessed the impact of each technology over 
each of the 13 SET modes to project an overall weighted SET cycle 
improvement in the 2014 model year of 3 percent, as detailed in RIA 
Chapter 2.4.2.9 through 2.4.2.14. All of these technologies represent 
engine enhancements already developed beyond the research phase and are 
available as ``off the shelf'' technologies for manufacturers to add to 
their engines during the engine's next design cycle. We have estimated 
that manufacturers will be able to implement these technologies on or 
before the 2014 engine model year. The agencies adopted a standard that 
therefore reflects a 100 percent application rate of this technology 
package. The agencies gave consideration to finalizing a more stringent 
standard based on the application of mechanical turbocompounding by 
model year 2014, a mechanical means of waste heat recovery, but 
concluded that manufacturers would have insufficient lead-time to 
complete the necessary product development and validation work 
necessary to include this technology. Implementing turbocompounding 
into an engine design must be done through a significant redesign of 
the engine architecture a process that typically takes 4 to 5 years. 
Hence, we believe that turbocompounding is a more appropriate 
technology for the agencies to consider in the 2017 timeframe.
    As explained earlier, EPA's heavy-duty highway engine standards for 
criteria pollutants apply in three year increments. The heavy-duty 
engine manufacturer product plans have fallen into three year cycles to 
reflect these requirements. The agencies are finalizing fuel 
consumption and CO2 emission standards recognizing the 
opportunity for technology improvements over this time frame 
(specifically, the addition of turbocompounding to the engine 
technology package) while reflecting the typical heavy-duty engine 
manufacturer product plan redesign and refresh cycles. Thus, the 
agencies are finalizing a more stringent standard for heavy-duty 
engines beginning in the 2017 model year.
    The MHDD and HHDD engine technology package for the 2017 model year 
includes the continued development of the 2014 model year technology 
package including refinement of the aftertreatment system plus 
turbocompounding. The agencies calculated overall reductions in the 
same manner as for the 2014 model year package. The weighted SET cycle 
improvements lead to a 6 percent reduction on the SET cycle, as 
detailed

[[Page 57215]]

in RIA Chapter 2.4.2.12. The agencies' final standards are premised on 
a 100 percent application rate of this technology package.
    Commenters noted that the National Academy of Sciences (NAS) study 
indicates that additional technology improvements can be made to heavy-
duty engines in MY 2014 and 2017. For diesel engine standards, the 
agencies evaluated the following technologies: Combustion system 
optimization, turbocharging and air handling systems, engine parasitic 
and friction reduction, integrated aftertreatment systems, 
electrification, and waste heat recovery.
    The agencies carefully evaluated the research supporting the NAS 
report and its recommendations and incorporated them to the extent 
practicable in the development of the HD program. While the NAS report 
suggests that greater engine improvements could be achieved by the use 
of technologies such as improved emission control systems and 
turbocompounding than do the agencies in this final action, we believe 
the standards being finalized represent the most stringent technically 
feasible for diesel engines used in tractors and vocational vehicles in 
the 2014 to 2017 model year time frame. The NAS study concluded that 
tractor engine fuel consumption can be reduced by approximately 15 
percent in the 2015 to 2020 time frame and vocational engine fuel 
consumption can be reduced by approximately 10 to 17 percent in the 
same time frame compared to a 2008 engine baseline.\236\ Throughout 
this presentation, the agencies' projections of performance 
improvements are measured relative to a 2010 engine performance 
baseline that itself reflects a four to five percent improvement over 
the 2008 engine baseline used by NAS. Based on a review of existing 
studies, NAS study authors found a range of reduction potential exists 
for improvements in combustion efficiency, electrification of 
accessories; improved emission control systems; and turbocompounding. 
The study found that improvements in combustion efficiency can provide 
reductions of 1 percent to 4 percent; electrification of accessories 
can provide reductions of 2 percent to 5 percent in a hybridized 
vehicle; improved emission control systems can provide a 1 percent to 4 
percent improvement (depending on whether the improvement is to the EGR 
or SCR system); and a 2.5 percent to 10 percent reduction is possible 
with mechanical or electrical turbocompounding. While the reductions 
being finalized in this regulation are lower than those published in 
the NAS study, the agencies believe that the percent reductions being 
finalized in these rules are consistent with the findings of the NAS 
study. The reasons for this are as follows.
---------------------------------------------------------------------------

    \236\ National Research Council, ``Technologies and Approaches 
to Reducing the Fuel Consumption of Medium- and Heavy-Duty 
Vehicles'' Figure S-1, page 4, National Acedemies Press, 2011.
---------------------------------------------------------------------------

    First, some technologies cannot be used by all manufacturers. For 
example, improved SCR conversion efficiency was projected by NAS to 
provide a 3 percent to 4 percent improvement in fuel consumption. 
Conversely, low temperature EGR was found to provide only a one percent 
improvement. While the majority of manufacturers do use SCR systems and 
will be able to realize the 3 percent to 4 percent improvement, not all 
manufacturers use SCR for NOX aftertreatment. Manufacturers 
that do not use SCR aftertreatment systems would only be able to 
realize the 1 percent improvement from low temperature EGR. The 
agencies need to take into consideration the entire market in setting 
the stringency of the standards and, in assessing feasibility and cost, 
cannot assume that all manufacturers will be able to use all 
technologies.
    Second, significant technical advances may be needed in order to 
realize the upper end of estimates for some technologies. For example, 
studies evaluated by NAS on turbocompounding found that a 2.5 percent 
to 10 percent reduction is feasible. However, only one system is 
available commercially and this system provides reductions on the low 
end of this range.\237\ Little technical information is available on 
the systems that achieve reductions in the upper range for 
turbocompounding. These systems are based on proprietary designs the 
improvement results for which have not yet been replicated by other 
companies or organizations. The agencies are assuming that all tractor 
engine manufacturers will use turbocompounding by 2017 model year. This 
will require a significant change in the design of heavy-duty tractor 
engines, one that represents the maximum technically feasible standard 
even at the low end of the assumed improvement spectrum.
---------------------------------------------------------------------------

    \237\ NAS 2010, page 53 cites Detroit Diesel Corporation, DD15 
Brochure, DDC-EMC-BRO-0003-0408, April 2008.
---------------------------------------------------------------------------

    Finally, different duty cycles used in the evaluation of medium- 
and heavy-duty engine technologies can affect reported fuel consumption 
improvements. For example, some technologies are dependent on high load 
conditions to provide the greatest reductions. The duty cycles used to 
evaluate some of the technologies considered by NAS differed 
significantly from that used by the agencies in the modeling for this 
rulemaking. Maximum and average speed was higher in some of the cycles 
used in the studies, for example, and one result was demonstrated on a 
nonroad engine cycle. In another example, the effectiveness of 
turbocompounding when evaluated on a duty cycle with higher engine load 
can show a greater reduction potential than when evaluated with a lower 
engine load. In addition, technologies such as improvements to cooling 
fans, air compressors, and air conditioning systems will not be 
demonstrated using the engine dynamometer test procedures being adopted 
in this final action because those components are not installed on the 
engine during the testing. The agencies selected the duty cycles for 
analysis, and for the final standards, that we believed best suited 
tractor engines.
    The agencies selected engine technologies and the estimated fuel 
reduction percentages for setting the standards. For the reasons stated 
above, the agencies believe the technologies and required improvements 
in fuel consumption represent the maximum feasible improvement, and are 
appropriate, cost-effective, and technologically feasible.
    We gave consideration to finalizing an even more stringent standard 
based on the use of waste heat recovery via a Rankine cycle (also 
called bottoming cycle) but concluded that there is insufficient lead-
time between now and 2017 for this promising technology to be developed 
and applied generally to all heavy-duty engines. TIAX noted in their 
report to the NAS committee that the engine improvements beyond 2015 
model year included in their report are highly uncertain, though they 
include Rankine cycle type waste heat recovery as applicable sometime 
between 2016 and 2020.\238\ The Department of Energy is working with 
industry to develop waste heat recovery systems for heavy-duty engines. 
At the Diesel Engine-Efficiency and Emissions Research (DEER) 
conference in 2010, Caterpillar presented details regarding their waste 
heat recovery systems development effort. In their presentation, 
Caterpillar clearly noted that the work is a research project and 
therefore does not imply

[[Page 57216]]

commercial viability.\239\ At the same conference, Concepts NREC 
presented a status of exhaust energy recovery in heavy-duty engines. 
The scope of Concepts NREC included the design and development of 
prototype parts.\240\ Cummins, also in coordination with DOE, is also 
active in developing exhaust energy recovery systems. Cummins made a 
presentation to the DEER conference in 2009 providing an update on 
their progress which highlighted opportunities to achieve a 10 percent 
engine efficiency improvement during their research, but indicated the 
need to focus their future development on areas with the highest 
recovery opportunities (such as EGR, exhaust, and charge air).\241\ 
Cummins also indicated that future development would focus on reducing 
the high additional costs and system complexity. Based upon the 
assessment of this information, the agencies did not include these 
technologies in determining the stringency of the final standards. 
However, we do believe the bottoming cycle approach represents a 
significant opportunity to reduce fuel consumption and GHG emissions in 
the future. EPA and NHTSA are therefore both finalizing provisions for 
advanced technology credits described in Section IV to create 
incentives for manufacturers to continue to invest to develop this 
technology.
---------------------------------------------------------------------------

    \238\ See TIAX, Note 198, Page 4-29.
    \239\ Kruiswyk, R. ``An Engine System Approach to Exhaust Waste 
Heat Recovery.'' Presented at DOE DEER Conference on September 29, 
2010. Last viewed on May 11, 2011 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2010/wednesday/presentations/deer10_kruiswyk.pdf.
    \240\ Cooper, D, N. Baines, N. Sharp. ``Organic Rankine Cycle 
Turbine for Exhaust Energy Recovery in a Heavy Truck Engine.'' 
Presented at the 2010 DEER Conference. Last viewed on May 11, 2011 
at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2010/wednesday/presentations/deer10_baines.pdf.
    \241\ Nelson, C. ``Exhaust Energy Recovery.'' Presented at the 
DOE DEER Conference on August 5, 2009. Last viewed on May 11, 2011 
at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2009/session5/deer09_nelson_1.pdf.
---------------------------------------------------------------------------

(iii) Derivation of Engine Standards
    EPA developed the final 2014 model year CO2 emissions 
standards (based on the SET cycle) for diesel engines by applying the 
three percent reduction from the technology package (just explained 
above) to the 2010 model year baseline values determined using the SET 
cycle. EPA developed the 2017 model year CO2 emissions 
standards for diesel engines while NHTSA similarly developed the 2017 
model year diesel engine fuel consumption standards by applying the 6 
percent reduction from the 2017 model year technology package 
(reflecting performance of turbocompounding plus the 2014 MY technology 
package) to the 2010 model year baseline values. The final standards 
are included in Table III-9.

                          Table III-9--Final Diesel Engine Standards Over the SET Cycle
----------------------------------------------------------------------------------------------------------------
                                                                                    MHD diesel      HHD diesel
                  Model year                                                          engine          engine
----------------------------------------------------------------------------------------------------------------
2014-2016.....................................  CO2 Standard (g/bhp-hr).........             502             475
                                                Voluntary Fuel Consumption                  4.93            4.67
                                                 Standard (gallon/100 bhp-hr).
2017 and later................................  CO2 Standard (g/bhp-hr).........             487             460
                                                Fuel Consumption (gallon/100 bhp-           4.78            4.52
                                                 hr).
----------------------------------------------------------------------------------------------------------------

(iv) Engine Technology Package Costs
    EPA has historically used two different approaches to estimate the 
indirect costs (sometimes called fixed costs) of regulations including 
costs for product development, machine tooling, new capital investments 
and other general forms of overhead that do not change with incremental 
changes in manufacturing volumes. Where the Agency could reasonably 
make a specific estimate of individual components of these indirect 
costs, EPA has done so. Where EPA could not readily make such an 
estimate, EPA has instead relied on the use of markup factors referred 
to as indirect cost multipliers (ICMs) to estimate these indirect costs 
as a ratio of direct manufacturing costs. In general, EPA has used 
whichever approach it believed could provide the most accurate 
assessment of cost on a case-by-case basis. The agencies' general 
approach used elsewhere in this action (for HD pickup trucks, gasoline 
engines, combination tractors, and vocational vehicles) estimates 
indirect costs based on the use of ICMs. See also 75 FR 25376. We have 
used this approach generally because these standards are based on 
installing new parts and systems purchased from a supplier. In such a 
case, the supplier is conducting the bulk of the research and 
development on the new parts and systems and including those costs in 
the purchase price paid by the original equipment manufacturer. In this 
situation, we believe that the ICM approach provides an accurate and 
clear estimate of the additional indirect costs borne by the 
manufacturer.
    For the heavy-duty diesel engine segment, however, the agencies do 
not consider this model to be the most appropriate because the primary 
cost is not expected to be the purchase of parts or systems from 
suppliers or even the production of the parts and systems, but rather 
the development of the new technology by the original equipment 
manufacturer itself. Most of the technologies the agencies are 
projecting the heavy-duty engine manufacturers will use for compliance 
reflect modifications to existing engine systems rather than wholesale 
addition of technology (e.g., improved turbochargers rather than adding 
a turbocharger where it did not exist before as was done in our light-
duty joint rulemaking in the case of turbo-downsizing). When the bulk 
of the costs come from refining an existing technology rather than a 
wholesale addition of technology, a specific estimate of indirect costs 
may be more appropriate. For example, combustion optimization may 
significantly reduce emissions and cost a manufacturer millions of 
dollars to develop but will lead to an engine that is no more expensive 
to produce. Using a bill of materials approach would suggest that the 
cost of the emissions control was zero reflecting no new hardware and 
ignoring the millions of dollars spent to develop the improved 
combustion system. Details of the cost analysis are included in the RIA 
Chapter 2. The agencies did not receive any comments regarding the cost 
approach used in the proposal.
    The agencies developed the engineering costs for the research and 
development of diesel engines with lower fuel consumption and 
CO2 emissions. The aggregate costs for engineering hours, 
technician support,

[[Page 57217]]

dynamometer cell time, and fabrication of prototype parts are estimated 
at $6.8 million (2009 dollars) per manufacturer per year over the five 
years covering 2012 through 2016. In aggregate, this averages out to 
$284 per engine during 2012 through 2016 using an annual sales volume 
of 600,000 light-, medium- and heavy-HD engines. The agencies received 
comments from Horriba regarding the assumption the agencies used in the 
proposal that said manufacturers would need to purchase new equipment 
for measuring N2O and the associated costs. Horriba provided 
information regarding the cost of stand-alone FTIR instrumentation 
(estimated at $50,000 per unit) and cost of upgrading existing emission 
measurement systems with NDIR analyzers (estimated at $25,000 per 
unit). The agencies further analyzed our assumptions along with 
Horriba's comments. Thus, we have revised the equipment costs estimates 
and assumed that 75 percent of manufacturers would update existing 
equipment while the other 25 percent would require new equipment. The 
agencies are estimating costs of $63,087 (2009 dollars) per engine 
manufacturer per engine subcategory (light-, medium- and heavy-HD) to 
cover the cost of purchasing photo-acoustic measurement equipment for 
two engine test cells. This would be a one-time cost incurred in the 
year prior to implementation of the standard (i.e., the cost would be 
incurred in 2013). In aggregate, this averages out to less than $1 per 
engine in 2013 using an annual sales volume of 600,000 light-, medium- 
and heavy-HD engines.
    Where we projected that additional new hardware was needed to the 
meet the final standards, we developed the incremental costs for those 
technologies and marked them up using the ICM approach. Table III-10 
below summarizes those estimates of cost on a per item basis. All costs 
shown in Table III-18, below, include a low complexity ICM of 1.15 and 
flat-portion of the curve learning is considered applicable to each 
technology.

 Table III-10--Heavy-Duty Diesel Engine Component Costs for Combination
                           Tractors\a\ (2009$)
------------------------------------------------------------------------
               Technology                      2014            2017
------------------------------------------------------------------------
Cylinder Head...........................              $6              $6
Turbo efficiency........................              18              17
EGR cooler..............................               4               3
Water pump..............................              91              84
Oil pump................................               5               4
Fuel pump...............................               5               4
Fuel rail...............................              10               9
Fuel injector...........................              11              10
Piston..................................               3               3
Engine Friction Reduction of Valvetrain.              82              76
Turbo-compounding (engines placed in                   0             875
 combination tractors only).............
MHHD and HHDD Total (combination                     234           1,091
 tractors)..............................
------------------------------------------------------------------------
Note:
\a\ Costs for aftertreatment improvements for MH and HH diesel engines
  are covered via the engineering costs (see text). For LH diesel
  engines, we have included the cost of aftertreatment improvements as a
  technology cost.

    The overall diesel engine technology package cost for an engine 
being placed in a combination tractor is $234 in the 2014 model year 
and $1,091 in the 2017 model year.
(v) Reasonableness of the Final Standards
    The final engine standards appear to be reasonable and consistent 
with the agencies' respective statutory authorities. With respect to 
the 2014 and 2017 MY standards, all of the technologies on which the 
standards are predicated have already been demonstrated in some 
capacity and their effectiveness is well documented. The final 
standards reflect a 100 percent application rate for these 
technologies. The costs of adding these technologies remain modest 
across the various engine classes as shown in Table III-10. Use of 
these technologies would add only a small amount to the cost of the 
vehicle,\242\ and the associated reductions are highly cost effective, 
an estimated $20 per ton of CO2eq per vehicle.\243\ This is 
even more cost effective than the estimated cost effectiveness for 
CO2eq removal under the light-duty vehicle rule, already 
considered by the agencies to be a highly cost effective 
reduction.\244\ Even the more expensive 2017 MY final standard still 
represents only a small fraction of the vehicle's total cost and is 
even more cost effective than the light-duty vehicle rule. Moreover, 
costs are more than offset by fuel savings. Accordingly, EPA and NHTSA 
view these standards as reflecting an appropriate balance of the 
various statutory factors under section 202(a) of the CAA and under 
NHTSA's EISA authority at 49 U.S.C. 32902(k)(2).
---------------------------------------------------------------------------

    \242\ Sample 2010 MY day cabs are priced at $89,000 while 2010 
MY sleeper cabs are priced at $113,000. See page 3 of ICF's 
``Investigation of Costs for Strategies to Reduce Greenhouse Gas 
Emissions for Heavy-Duty On-Road Vehicles.'' July 2010.
    \243\ See Tractor CO2 savings and technology costs in 
Table 7-5 in RIA chapter 7.
    \244\ The light-duty rule had an estimated cost per ton of $50 
when considering the vehicle program costs only and a cost of -$210 
per ton considering the vehicle program costs along with fuel 
savings in 2030. See 75 FR 25515, Table III.H.3-1.
---------------------------------------------------------------------------

(vi) Temporary Alternative Standard for Certain Engine Families
    As discussed above in Section II.B(2)(b), notwithstanding the 
general reasonableness of the final standards, the agencies recognize 
that heavy-duty engines have never been subject to GHG or fuel 
consumption (or fuel economy) standards and that such control has not 
necessarily been an independent priority for manufacturers. The result 
is that there are a group of legacy engines with emissions higher than 
the industry baseline for which compliance with the final 2014 MY 
standards may be more challenging and for which there may simply be 
inadequate lead time. The issue is not whether these engines' GHG and 
fuel consumption performance cannot be improved by utilizing the 
technology packages on which the final standards are based. Those 
technologies can be utilized by all diesel engines installed in 
tractors and the same degree of reductions obtained. Rather the 
underlying base engine components of these engines reflect designs that 
are decades old and therefore have base performance levels below what 
is typical for the industry as a whole

[[Page 57218]]

today. Manufacturers have been gradually replacing these legacy 
products with new engines. Engine manufacturers have indicated to the 
agencies they will have to align their planned replacement of these 
products with our final standards and at the same time add additional 
technologies beyond those identified by the agencies as the basis for 
the final standard. Because these changes will reflect a larger degree 
of overall engine redesign, manufacturers may not be able to complete 
this work for all of their legacy products prior to model year 2014. To 
pull ahead these already planned engine replacements would be 
impossible as a practical matter given the engineering structure and 
lead-times inherent in the companies' existing product development 
processes. We have also concluded that the use of fleet averaging would 
not address the issue of legacy engines because each manufacturer 
typically produces only a limited line of MHDD and HHDD engines. 
Because there are ample fleetwide averaging opportunities for heavy-
duty pickups and vans, the agencies do not perceive similar 
difficulties for these vehicles.
    Facing a similar issue in the light-duty vehicle rule, EPA adopted 
a Temporary Lead Time Allowance provision whereby a limited number of 
vehicles of a subset of manufacturers would meet an alternative 
standard in the early years of the program, affording them sufficient 
lead time to meet the more stringent standards applicable in later 
model years. See 75 FR 25414-25418. The agencies are finalizing a 
similar approach here. As explained above in Section II.B.(2)(b), the 
agencies are finalizing a regulatory alternative whereby a 
manufacturer, for a limited period, would have the option to comply 
with a unique standard requiring the same level of reduction of 
emissions (i.e., percent removal) and fuel consumption as otherwise 
required, but the reduction would be measured from its own 2011 model 
year baseline. We are thus finalizing an optional standard whereby 
manufacturers would elect to have designated engine families meet a 
standard of 3 percent reduction from their 2011 baseline emission and 
fuel consumption levels for that engine family or engine subcategory. 
Our assessment is that this three percent reduction is appropriate 
based on use of similar technology packages at similar cost as we have 
estimated for the primary program. In the NPRM, we solicited comment on 
extending this alternative (See 75 FR at 74202). As explained earlier, 
we have decided not to allow the alternative standard to continue past 
the 2016 MY. By this time, the engines should have gone through a 
redesign cycle which will allow manufacturers to replace those legacy 
engines which resulted in abnormally high baseline emission and fuel 
consumption levels and to achieve the MY 2017 standards which would be 
feasible using the technology package set out above (optimized 
NOX aftertreatment, improved EGR, reductions in parasitic 
losses, and turbocharging). Manufacturers would, of course, be free to 
adopt other technology paths which meet the final MY 2017 standards.
    Since the alternative standard is premised on the need for 
additional lead time, manufacturers would first have to utilize all 
available flexibilities which could otherwise provide that lead time. 
Thus, as proposed, the alternative would not be available unless and 
until a manufacturer had exhausted all available credits and credit 
opportunities, and engines under the alternative standard could not 
generate credits. See also 75 FR 25417-25419 (similar approach for 
vehicles which are part of Temporary Lead Time Allowance under the 
light-duty vehicle rule). We are finalizing that manufacturers can 
select engine families for this alternative standard without agency 
approval, but are requiring that manufacturers notify the agency of 
their choice and also requiring manufacturers to include in that 
notification a demonstration that it has exhausted all available 
credits and credit opportunities. Manufacturers would also have to 
demonstrate their 2011 baseline calculations as part of the 
certification process for each engine family for which the manufacturer 
elects to use the alternative standard. See Section V.C.1(b)(i) below.
(vii) ther Engine Standards Considered
    The agencies are not finalizing engine standards less stringent 
than the final standards because the agencies believe these final 
standards are appropriate, highly cost effective, and technologically 
feasible, as just described.
    The agencies considered finalizing engine standards which are more 
stringent. Since the final standards reflect 100 percent utilization of 
the various technology packages, some additional technology would have 
to be added. The agencies are finalizing 2017 model year standards 
based on the use of turbocompounding. As discussed above in Section 
III.A.2.b.iii, the agencies considered the inclusion of more advanced 
heat recovery systems, such as Rankine or bottoming cycles, which would 
provide further reductions. However, the agencies are not finalizing 
this level of stringency because our assessment is that these 
technologies would not be available for production by the 2017 model 
year.

B. Heavy-Duty Pickup Trucks and Vans

    This section describes the process the agencies used to develop the 
standards the agencies are finalizing for HD pickups and vans. We 
started by gathering available information about the fuel consumption 
and CO2 emissions from recent model year vehicles. The core 
portion of this information comes primarily from EPA's certification 
databases, CFEIS and Verify, which contain the publicly available data 
\245\ regarding emission and fuel economy results. This information is 
not extensive because manufacturers have not been required to chassis 
test HD diesel vehicles for EPA's criteria pollutant emissions 
standards, nor have they been required to conduct any testing of heavy-
duty vehicles on the highway cycle. Nevertheless, enough certification 
activity has occurred for diesels under EPA's optional chassis-based 
program, and, due to a California NOX requirement for the 
highway test cycle, enough test results have been voluntarily reported 
for both diesel and gasoline vehicles using the highway test cycle, to 
yield a reasonably robust data set. To supplement this data set, for 
purposes of this rulemaking EPA initiated its own testing program using 
in-use vehicles. This program and the results from it thus far are 
described in a memorandum to the docket for this rulemaking.\246\
---------------------------------------------------------------------------

    \245\ http://www.epa.gov/otaq/certdata.htm.
    \246\ Memorandum from Cleophas Jackson, U.S.EPA, to docket EPA-
HQ-OAR-2010-0162, ``Heavy-Duty Greenhouse Gas and Fuel Consumption 
Test Program Summary'', September 20, 2010.
---------------------------------------------------------------------------

    Heavy-duty pickup trucks and vans are sold in a variety of 
configurations to meet market demands. Among the differences in these 
configurations that affect CO2 emissions and fuel 
consumption are curb weight, GVWR, axle ratio, and drive wheels (two-
wheel drive or four-wheel drive). Because the currently-available test 
data set does not capture all of these configurations, it is necessary 
to extend that data set across the product mix using adjustment 
factors. In this way a test result from, say a truck with two-wheel 
drive, 3.73:1 axle ratio, and 8000 lb test weight, can be used to model 
emissions and fuel consumption from a truck of the same basic body 
design, but with four-wheel drive, a 4.10:1 axle ratio, and 8,500 lb 
test weight. The adjustment factors are

[[Page 57219]]

based on data from testing in which only the parameters of interest are 
varied. These parameterized adjustments and their basis are also 
described in a memorandum to the docket for this rulemaking.\247\
---------------------------------------------------------------------------

    \247\ Memorandum from Anthony Neam and Jeff Cherry, U.S.EPA, to 
docket EPA-HQ-OAR-2010-0162, October 18, 2010.
---------------------------------------------------------------------------

    The agencies requested and received from each of the three major 
manufacturers confidential information for each model and 
configuration, indicating the values of each of these key parameters as 
well as the annual production (for the U.S. market). Production figures 
are useful because, under our final standards for HD pickups and vans, 
compliance is judged on the basis of production-weighted (corporate 
average) emissions or fuel consumption level, not individual vehicle 
levels. For consistency and to avoid confounding the analysis with data 
from unusual market conditions in 2009, the production and vehicle 
specification data is from the 2008 model year. We made the simplifying 
assumption that these sales figures reasonably approximate future sales 
for purposes of this analysis.
    One additional assessment was needed to make the data set useful as 
a baseline for the standards selection. Because the appropriate 
standards are determined by applying efficiency-improving technologies 
to the baseline fleet, it is necessary to know the level of penetration 
of these technologies in the latest model year (2010). This information 
was also provided confidentially by the manufacturers. Generally, the 
agencies found that the HD pickup and van fleet was at a roughly 
consistent level of technology application, with (1) the transition 
from 4-speed to 5- or 6-speed automatic transmissions mostly 
accomplished, (2) coupled cam phasing to achieve variable valve control 
on gasoline engines likewise mostly in place,\248\ and (3) substantial 
remaining potential for optimizing catalytic diesel NOX 
aftertreatment to improve fuel economy (the new heavy-duty 
NOX standards having taken effect in the 2010 model year).
---------------------------------------------------------------------------

    \248\ See Section III.B(2)(a) for our response to comments 
arguing for inclusion of this technology in the list of technologies 
needed to meet the standards.
---------------------------------------------------------------------------

    Taking this 2010 baseline fleet, and applying the technologies 
determined to be feasible and appropriate by the 2018 model year, along 
with their effectiveness levels, the agencies could then make a 
determination of appropriate final standards. The assessment of 
feasibility, described immediately below, takes into account the 
projected costs of these technologies. The derivation of these costs, 
largely based on analyses developed in the light-duty GHG and fuel 
economy rulemaking, are described in Section III.B(3).
    Our assessment concluded that the technologies that the agencies 
considered feasible and appropriate for HD pickups and vans could be 
consistently applied to essentially all vehicles across this sector by 
the 2018 model year. Therefore we did not apply varying penetration 
rates across vehicle types and models in developing and evaluating the 
final standards.
    Since the manufacturers of HD pickups and vans generally only have 
one basic pickup truck and van with different versions (i.e., different 
wheel bases, cab sizes, two-wheel drive, four-wheel drive, etc.) and do 
not have the flexibility of the light-duty fleet to coordinate model 
improvements over several years, changes to the HD pickups and vans to 
meet new standards must be carefully planned with the redesign cycle 
taken into account. The opportunities for large-scale changes (e.g., 
new engines, transmission, vehicle body and mass) thus occur less 
frequently than in the light-duty fleet, typically at spans of 8 or 
more years. However, opportunities for gradual improvements not 
necessarily linked to large scale changes can occur between the 
redesign cycles. Examples of such improvements are upgrades to an 
existing vehicle model's engine, transmission and aftertreatment 
systems. Given this long redesign cycle and our understanding with 
respect to where the different manufacturers are in that cycle, the 
agencies have initially determined that the full implementation of the 
final standards would be feasible and appropriate by the 2018 model 
year.
    Although we did not determine a technological need for less than 
full implementation of any technology, we did decide that a phased 
implementation schedule would be appropriate to accommodate 
manufacturers' redesign workload and product schedules, especially in 
light of this sector's relatively low sales volumes and long product 
cycles. We did not determine a specific cost of implementing the final 
standards immediately in 2014 without a phase-in, but we assessed it to 
be much higher than the cost of the phase-in we are finalizing, due to 
the workload and product cycle disruptions it would cause, and also due 
to manufacturers' resulting need to develop some of these technologies 
for heavy-duty applications sooner than or simultaneously with light-
duty development efforts. See generally 75 FR 25467-25468 explaining 
why attempting major changes outside the redesign cycle period raises 
very significant issues of both feasibility and cost. On the other 
hand, waiting until 2018 before applying any new standards could miss 
the opportunity to achieve meaningful and cost-effective early 
reductions not requiring a major product redesign.
    The final phase-in schedule, 15-20-40-60-100 percent in 2014-2015-
2016-2017-2018, respectively, was chosen to strike a balance between 
meaningful reductions in the early years (reflecting the technologies' 
penetration rates of 15 and 20 percent) and providing manufacturers 
with needed lead time via a gradually accelerating ramp-up of 
technology penetration.\249\ By expressing the final phase-in in terms 
of increasing fleetwide stringency for each manufacturer, while also 
providing for credit generation and use (including averaging, carry-
forward, and carry-back), we believe our program affords manufacturers 
substantial flexibility to satisfy the phase-in through a variety of 
pathways, among them, the gradual application of technologies across 
the fleet (averaging a fifth of total production in each year), greater 
application levels on only a portion of the fleet, or a mix of the two.
---------------------------------------------------------------------------

    \249\ The NHTSA program provides voluntary standards for model 
years 2014 and 2015. NHTSA and EPA are also providing an alternative 
standards phase-in that meets EISA's requirement for three years of 
regulatory stability. See Section II.C.d.ii for a more detailed 
discussion.
---------------------------------------------------------------------------

    We considered setting more stringent standards that would require 
the application of additional technologies by 2018. We expect, in fact, 
that some of these technologies may well prove feasible and cost-
effective in this time frame, and may even become technologies of 
choice for individual manufacturers. This dynamic has played out in EPA 
programs before and highlights the value of setting performance-based 
standards that leave engineers the freedom to find the most cost-
effective solutions.
    However, the agencies do believe that at this stage there is not 
enough information to conclude that the additional technologies provide 
an appropriate basis for standard-setting. For example, we believe that 
42V stop-start systems can be applied to gasoline vehicles with 
significant GHG and fuel consumption benefits, but we recognize that 
there is uncertainty at this time over the cost-effectiveness of these 
systems in heavy-duty applications, and legitimate concern with 
customer

[[Page 57220]]

acceptance of vehicles with high GCWR towing large loads that would 
routinely stop running at idle. Hybrid electric technology likewise 
could be applied to heavy-duty vehicles, and in fact has already been 
so applied on a limited basis. However, the development, design, and 
tooling effort needed to apply this technology to a vehicle model is 
quite large, and seems less likely to prove cost-effective in this time 
frame, due to the small sales volumes relative to the light-duty 
sector. Here again, potential customer acceptance would need to be 
better understood because the smaller engines that facilitate much of a 
hybrid's benefit are typically at odds with the importance pickup 
trucks buyers place on engine horsepower and torque, whatever the 
vehicle's real performance.
    We also considered setting less stringent standards calling for a 
more limited set of applied technologies. However, our assessment 
concluded with a high degree of confidence that the technologies on 
which the final standards are premised are clearly available at 
reasonable cost in the 2014-2018 time frame, and that the phase-in and 
other flexibility provisions allow for their application in a very 
cost-effective manner, as discussed in this section below.
    More difficult to characterize is the degree to which more or less 
stringent standards might be appropriate because of under- or over-
estimating effectiveness of the technologies whose performance is the 
basis of the final standards. Our basis for these estimates is 
described in the following Section 0. Because for the most part these 
technologies have not yet been applied to HD pickups and vans, even on 
a limited basis, we are relying to some degree on engineering judgment 
in predicting their effectiveness. Even so, we believe that we have 
applied this judgment using the best information available, primarily 
from our recent rulemaking on light-duty vehicle GHGs and fuel economy, 
and have generated a robust set of effectiveness values.
(1) What technologies did the agencies consider?
    The agencies considered over 35 vehicle technologies that 
manufacturers could use to improve the fuel consumption and reduce 
CO2 emissions of their vehicles during MYs 2014-2018. The 
majority of the technologies described in this section is readily 
available, well known, and could be incorporated into vehicles once 
production decisions are made. Several of the technologies have already 
been introduced into the heavy-duty pickup and van market (i.e., 
variable valve timing, improved accessories, etc.) in a limited number 
of applications. Other technologies considered may not currently be in 
production, but are beyond the research phase and under development, 
and are expected to be in production in highway vehicles over the next 
few years. These are technologies which are capable of achieving 
significant improvements in fuel economy and reductions in 
CO2 emissions, at reasonable costs. The agencies did not 
consider technologies in the research stage because there is 
insufficient time for such technologies to move from research to 
production during the model years covered by this final action.
    The agencies received comments regarding applicability of certain 
advanced technologies described in the TIAX 2009 report submitted to 
NAS. Specifically mentioned were turbocharging and downsizing of 
gasoline vehicles and hydraulic hybrid systems. While turbocharging and 
downsizing of gasoline vehicles was a principal technology underlying 
the standards in the light-duty rule, the agencies determined that in 
the realm of heavy-duty vehicles, this approach provides much less 
benefit to vehicles which are required to regularly operate at high and 
sustained loads. In light-duty applications, downsizing of a typically 
oversized engine largely results in benefits mainly under partial and 
light load conditions. This approach is more applicable to light-duty 
vehicles because they infrequently require high or full power. Further, 
while turbo downsizing was already occurring in a portion of the light-
duty fleet, it has not been demonstrated in the heavy-duty fleet, 
likely due to concerns with durability of this technology in the 
sustained high-load duty cycles frequently encountered. Similarly, 
other light-duty technologies (i.e., cylinder deactivation, engine 
start stop) were also determined to not be compatible with the duty 
cycle of heavy-duty vehicles for similar reasons. Due to the relatively 
aggressive implementation of this program and the lack of 
commercialization in the heavy-duty market, hydraulic hybrid systems 
were not considered a technology that could be implemented in the time 
frame of this program for the HD pickup and van sector. The fact that 
no HD pickup or van hydraulic hybrids have been, or are the verge of 
being marketed makes their widespread introduction before the MY 2018 
final year of the phase-in very unlikely.
    The technologies considered in the agencies' analysis are briefly 
described below. They fall into five broad categories: engine 
technologies, transmission technologies, vehicle technologies, 
electrification/accessory technologies, and hybrid technologies.
    In this class of trucks and vans, diesel engines are installed in 
about half of all vehicles. The ratio between gasoline and diesel 
engine purchases by consumers has tended to track changes in the 
overall cost of oil and the relative cost of gasoline and diesel fuels. 
When oil prices are higher, diesel sales tend to increase. This trend 
has reversed when oil prices fall or when diesel fuel prices are 
significantly higher than gasoline. In the context of our technology 
discussion for heavy-duty pickups and vans, we are treating gasoline 
and diesel engines separately so each has a set of baseline 
technologies. We discuss performance improvements in terms of changes 
to those baseline engines. Our cost and inventory estimates contained 
elsewhere reflect the current fleet baseline with an appropriate mix of 
gasoline and diesel engines. Note that we are not basing the final 
standards on a targeted switch in the mix of diesel and gasoline 
vehicles. We believe our final standards require similar levels of 
technology development and cost for both diesel and gasoline vehicles. 
Hence the final program does not force, nor does it discourage, changes 
in a manufacturer's fleet mix between gasoline and diesel vehicles. 
Although we considered setting a single standard based on the 
performance level possible for diesel vehicles, we are not finalizing 
such an approach because the potential disruption in the HD pickup and 
van market from a forced shift would not be justified. Types of engine 
technologies that improve fuel efficiency and reduce CO2 
emissions include the following:
     Low-friction lubricants--low viscosity and advanced low 
friction lubricants oils are now available with improved performance 
and better lubrication. If manufacturers choose to make use of these 
lubricants, they would need to make engine changes and possibly conduct 
durability testing to accommodate the low-friction lubricants.
     Reduction of engine friction losses--can be achieved 
through low-tension piston rings, roller cam followers, improved 
material coatings, more optimal thermal management, piston surface 
treatments, and other improvements in the design of engine components 
and subsystems that improve engine operation.
     Cylinder deactivation--deactivates the intake and exhaust 
valves and prevents fuel injection into some cylinders during light-
load operation.

[[Page 57221]]

The engine runs temporarily as though it were a smaller engine which 
substantially reduces pumping losses.
     Variable valve timing--alters the timing of the intake 
valve, exhaust valve, or both, primarily to reduce pumping losses, 
increase specific power, and control residual gases.
     Stoichiometric gasoline direct-injection technology--
injects fuel at high pressure directly into the combustion chamber to 
improve cooling of the air/fuel charge within the cylinder, which 
allows for higher compression ratios and increased thermodynamic 
efficiency.
     Diesel engine improvements and diesel aftertreatment 
improvements--improved EGR systems and advanced timing can provide more 
efficient combustion and, hence, lower fuel consumption. Aftertreatment 
systems are a relatively new technology on diesel vehicles and, as 
such, improvements are expected in coming years that allow the 
effectiveness of these systems to improve while reducing the fuel and 
reductant demands of current systems.
    Types of transmission technologies considered include:
     Improved automatic transmission controls --optimizes shift 
schedule to maximize fuel efficiency under wide ranging conditions, and 
minimizes losses associated with torque converter slip through lock-up 
or modulation.
     Six-, seven-, and eight-speed automatic transmissions--the 
gear ratio spacing and transmission ratio are optimized for a broader 
range of engine operating conditions specific to the mating engine.
    Types of vehicle technologies considered include:
     Low-rolling-resistance tires--have characteristics that 
reduce frictional losses associated with the energy dissipated in the 
deformation of the tires under load, therefore improving fuel 
efficiency and reducing CO2 emissions.
     Aerodynamic drag reduction--is achieved by changing 
vehicle shape or reducing frontal area, including skirts, air dams, 
underbody covers, and more aerodynamic side view mirrors.
     Mass reduction and material substitution--Mass reduction 
encompasses a variety of techniques ranging from improved design and 
better component integration to application of lighter and higher-
strength materials. Mass reduction is further compounded by reductions 
in engine power and ancillary systems (transmission, steering, brakes, 
suspension, etc.). The agencies recognize there is a range of diversity 
and complexity for mass reduction and material substitution 
technologies and there are many techniques that automotive suppliers 
and manufacturers are using to achieve the levels of this technology 
that the agencies have modeled in our analysis for this program.
    Types of electrification/accessory and hybrid technologies 
considered include:
     Electric power steering and Electro-Hydraulic power 
steering--are electrically-assisted steering systems that have 
advantages over traditional hydraulic power steering because it 
replaces a continuously operated hydraulic pump, thereby reducing 
parasitic losses from the accessory drive.
     Improved accessories--may include high efficiency 
alternators, electrically driven (i.e., on-demand) water pumps and 
cooling fans. This excludes other electrical accessories such as 
electric oil pumps and electrically driven air conditioner compressors.
     Air Conditioner Systems--These technologies include 
improved hoses, connectors and seals for leakage control. They also 
include improved compressors, expansion valves, heat exchangers and the 
control of these components for the purposes of improving tailpipe 
CO2 emissions as a result of A/C use.\250\
---------------------------------------------------------------------------

    \250\ See RIA Chapter 2.3 for more detailed technology 
descriptions.
---------------------------------------------------------------------------

(2) How did the agencies determine the costs and effectiveness of each 
of these technologies?
    Building on the technical analysis underlying the light-duty 2012-
2016 MY vehicle rule, the agencies took a fresh look at technology cost 
and effectiveness values for purposes of this final action. For costs, 
the agencies reconsidered both the direct or ``piece'' costs and 
indirect costs of individual components of technologies. For the direct 
costs, the agencies followed a bill of materials (BOM) approach 
employed by NHTSA and EPA in the light-duty rule.
    For two technologies, stoichiometric gasoline direct injection 
(SGDI) and turbocharging with engine downsizing, the agencies relied to 
the extent possible on the available tear-down data and scaling 
methodologies used in EPA's ongoing study with FEV, Incorporated. This 
study consists of complete system tear-down to evaluate technologies 
down to the nuts and bolts to arrive at very detailed estimates of the 
costs associated with manufacturing them.\251\
---------------------------------------------------------------------------

    \251\ U.S. Environmental Protection Agency, ``Draft Report--
Light-Duty Technology Cost Analysis Pilot Study,'' Contract No. EP-
C-07-069, Work Assignment 1-3, September 3, 2009.
---------------------------------------------------------------------------

    For the other technologies, considering all sources of information 
and using the BOM approach, the agencies worked together intensively to 
determine component costs for each of the technologies and build up the 
costs accordingly. Where estimates differ between sources, we have used 
engineering judgment to arrive at what we believe to be the best cost 
estimate available today, and explained the basis for that exercise of 
judgment.
    Once costs were determined, they were adjusted to ensure that they 
were all expressed in 2009 dollars using a ratio of gross domestic 
product (GDP) values for the associated calendar years,\252\ and 
indirect costs were accounted for using the new approach developed by 
EPA and used in the light-duty 2012-2016 MY vehicle rule. NHTSA and EPA 
also reconsidered how costs should be adjusted by modifying or scaling 
content assumptions to account for differences across the range of 
vehicle sizes and functional requirements, and adjusted the associated 
material cost impacts to account for the revised content, although some 
of these adjustments may be different for each agency due to the 
different vehicle subclasses used in their respective models.
---------------------------------------------------------------------------

    \252\ NHTSA examined the use of the CPI multiplier instead of 
GDP for adjusting these dollar values, but found the difference to 
be exceedingly small--only $0.14 over $100.
---------------------------------------------------------------------------

    Regarding estimates for technology effectiveness, NHTSA and EPA 
used the estimates from the light-duty rule as a baseline but adjusted 
them as appropriate, taking into account the unique requirement of the 
heavy-duty test cycles to test at curb weight plus half payload versus 
the light-duty requirement of curb plus 300 lb. The adjustments were 
made on an individual technology basis by assessing the specific impact 
of the added load on each technology when compared to the use of the 
technology on a light-duty vehicle. The agencies also considered other 
sources such as the 2010 NAS Report, recent CAFE compliance data, and 
confidential manufacturer estimates of technology effectiveness. NHTSA 
and EPA engineers reviewed effectiveness information from the multiple 
sources for each technology and ensured that such effectiveness 
estimates were based on technology hardware consistent with the BOM 
components used to estimate costs. Together, the agencies compared the 
multiple estimates and assessed their validity, taking care to ensure 
that common BOM definitions and other

[[Page 57222]]

vehicle attributes such as performance and drivability were taken into 
account.
    The agencies note that the effectiveness values estimated for the 
technologies may represent average values applied to the baseline fleet 
described earlier, and do not reflect the potentially-limitless 
spectrum of possible values that could result from adding the 
technology to different vehicles. For example, while the agencies have 
estimated an effectiveness of 0.5 percent for low friction lubricants, 
each vehicle could have a unique effectiveness estimate depending on 
the baseline vehicle's oil viscosity rating. Similarly, the reduction 
in rolling resistance (and thus the improvement in fuel efficiency and 
the reduction in CO2 emissions) due to the application of 
LRR tires depends not only on the unique characteristics of the tires 
originally on the vehicle, but on the unique characteristics of the 
tires being applied, characteristics which must be balanced between 
fuel efficiency, safety, and performance. Aerodynamic drag reduction is 
much the same--it can improve fuel efficiency and reduce CO2 
emissions, but it is also highly dependent on vehicle-specific 
functional objectives. For purposes of this NPRM, NHTSA and EPA believe 
that employing average values for technology effectiveness estimates is 
an appropriate way of recognizing the potential variation in the 
specific benefits that individual manufacturers (and individual 
vehicles) might obtain from adding a fuel-saving technology.
    The following section contains a detailed description of our 
assessment of vehicle technology cost and effectiveness estimates. The 
agencies note that the technology costs included in this NPRM take into 
account only those associated with the initial build of the vehicle.
(a) Engine Technologies
    NHTSA and EPA have reviewed the engine technology estimates used in 
the light-duty rule. In doing so NHTSA and EPA reconsidered all 
available sources and updated the estimates as appropriate. The section 
below describes both diesel and gasoline engine technologies considered 
for this program.
(i) Low Friction Lubricants
    One of the most basic methods of reducing fuel consumption in both 
gasoline and diesel engines is the use of lower viscosity engine 
lubricants. More advanced multi-viscosity engine oils are available 
today with improved performance in a wider temperature band and with 
better lubricating properties. This can be accomplished by changes to 
the oil base stock (e.g., switching engine lubricants from a Group I 
base oils to lower-friction, lower viscosity Group III synthetic) and 
through changes to lubricant additive packages (e.g., friction 
modifiers and viscosity improvers). The use of 5W-30 motor oil is now 
widespread and auto manufacturers are introducing the use of even lower 
viscosity oils, such as 5W-20 and 0W-20, to improve cold-flow 
properties and reduce cold start friction. However, in some cases, 
changes to the crankshaft, rod and main bearings and changes to the 
mechanical tolerances of engine components may be required. In all 
cases, durability testing would be required to ensure that durability 
is not compromised. The shift to lower viscosity and lower friction 
lubricants will also improve the effectiveness of valvetrain 
technologies such as cylinder deactivation, which rely on a minimum oil 
temperature (viscosity) for operation.
    Based on the light-duty 2012-2016 MY vehicle rule, and previously-
received confidential manufacturer data, NHTSA and EPA estimated the 
effectiveness of low friction lubricants to be between 0 to 1 percent.
    In the light-duty rule, the agencies estimated the cost of moving 
to low friction lubricants at $3 per vehicle (2007$). That estimate 
included a markup of 1.11 for a low complexity technology. For HD 
pickups and vans, we are using the same base estimate but have marked 
it up to 2009 dollars using the GDP price deflator and have used a 
markup of 1.24 for a low complexity technology to arrive at a value of 
$4 per vehicle. As in the light-duty rule, learning effects are not 
applied to costs for this technology and, as such, this estimate 
applies to all model years.253 254
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    \253\ Note that throughout the cost estimates for this HD 
analysis, the agencies have used slightly higher markups than those 
used in the 2012-2016 MY light-duty vehicle rule. The new, slightly 
higher ICMs include return on capital of roughly 6%, a factor that 
was not included in the light-duty analysis. The markups are also 
higher than those used the in proposal for this action. That change 
has to do with our decision to base the ICMs solely on EPA internal 
work rather than averaging that work with earlier work done under 
contract to EPA by RTI, International. That change is discussed in 
Section VIII.C of this preamble and is detailed in Chapter 2 of the 
RIA (See RIA 2.2.1)
    \254\ Note that the costs developed for low friction lubes for 
this analysis reflect the costs associated with any engine changes 
that would be required as well as any durability testing that may be 
required.
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(ii) Engine Friction Reduction
    In addition to low friction lubricants, manufacturers can also 
reduce friction and improve fuel consumption by improving the design of 
both diesel and gasoline engine components and subsystems. 
Approximately 10 percent of the energy consumed by a vehicle is lost to 
friction, and just over half is due to frictional losses within the 
engine.\255\ Examples include improvements in low-tension piston rings, 
piston skirt design, roller cam followers, improved crankshaft design 
and bearings, material coatings, material substitution, more optimal 
thermal management, and piston and cylinder surface treatments. 
Additionally, as computer-aided modeling software continues to improve, 
more opportunities for evolutionary friction reductions may become 
available.
---------------------------------------------------------------------------

    \255\ ``Impact of Friction Reduction Technologies on Fuel 
Economy,'' Fenske, G. Presented at the March 2009 Chicago Chapter 
Meeting of the `Society of Tribologists and Lubricated Engineers' 
Meeting, March 18th, 2009. Available at: http://www.chicagostle.org/program/2008-2009/Impact%20of%20Friction%20Reduction%20Technologies%20on%20Fuel%20Economy%20-%20with%20VGs%20removed.pdf (last accessed July 9, 2009).
---------------------------------------------------------------------------

    All reciprocating and rotating components in the engine are 
potential candidates for friction reduction, and minute improvements in 
several components can add up to a measurable fuel efficiency 
improvement. The light-duty 2012-2106 MY vehicle rule, the 2010 NAS 
Report, and NESCCAF and Energy and Environmental Analysis reports, as 
well as confidential manufacturer data, indicate a range of 
effectiveness for engine friction reduction to be between 1 to 3 
percent. NHTSA and EPA continue to believe that this range is accurate.
    Consistent with the light-duty rule, the agencies estimate the cost 
of this technology at $15 per cylinder compliance cost (2008$), 
including the low complexity ICM markup value of 1.24. Learning impacts 
are not applied to the costs of this technology and, as such, this 
estimate applies to all model years. This cost is multiplied by the 
number of engine cylinders.
(iii) Coupled Cam Phasing
    Valvetrains with coupled (or coordinated) cam phasing can modify 
the timing of both the inlet valves and the exhaust valves an equal 
amount by phasing the camshaft of an overhead valve engine. For 
overhead valve engines, which have only one camshaft to actuate both 
inlet and exhaust valves, couple cam phasing is the only variable valve 
timing implementation option available and requires only one cam 
phaser. Based on the light-duty rule, previously-received confidential 
manufacturer data, and the NESCCAF report, NHTSA and EPA estimated the 
effectiveness of couple cam phasing to be between 1 and 4 percent. 
NHTSA

[[Page 57223]]

and EPA reviewed this estimate for purposes of the NPRM, and continue 
to find it accurate.
    The agencies received comments questioning the exclusion of cam 
phasing from the technology packages. During the rulemaking process, 
manufacturers introduced many new or updated gasoline engines resulting 
in the majority of the 2010 gasoline heavy-duty engines including cam 
phasing, and so we now consider this technology to be in the baseline 
fleet. Because of this, the baseline analysis of technology for the 
2010 heavy-duty gasoline fleet already includes the benefits of cam 
phasing and therefore it is not appropriate for the agencies to include 
this as a technology that is available for most manufactures to add to 
their current gasoline engines.
(iv) Cylinder Deactivation
    In conventional spark-ignited engines throttling the airflow 
controls engine torque output. At partial loads, efficiency can be 
improved by using cylinder deactivation instead of throttling. Cylinder 
deactivation can improve engine efficiency by disabling or deactivating 
(usually) half of the cylinders when the load is less than half of the 
engine's total torque capability--the valves are kept closed, and no 
fuel is injected--as a result, the trapped air within the deactivated 
cylinders is simply compressed and expanded as an air spring, with 
reduced friction and heat losses. The active cylinders combust at 
almost double the load required if all of the cylinders were operating. 
Pumping losses are significantly reduced as long as the engine is 
operated in this ``part-cylinder'' mode.
    Cylinder deactivation control strategy relies on setting maximum 
manifold absolute pressures or predicted torque within a range in which 
it can deactivate the cylinders. Noise and vibration issues reduce the 
operating range to which cylinder deactivation is allowed, although 
manufacturers are exploring vehicle changes that enable increasing the 
amount of time that cylinder deactivation might be suitable. Some 
manufacturers may choose to adopt active engine mounts and/or active 
noise cancellations systems to address Noise Vibration and Harshness 
(NVH) concerns and to allow a greater operating range of activation. 
Cylinder deactivation is a technology keyed to more lightly loaded 
operation, and so may be a less likely technology choice for 
manufacturers designing for effectiveness in the loaded condition 
required for testing, and in the real world that involves frequent 
operation with heavy loads.
    Cylinder deactivation has seen a recent resurgence thanks to better 
valvetrain designs and engine controls. General Motors and Chrysler 
Group have incorporated cylinder deactivation across a substantial 
portion of their light-duty V8-powered lineups.
    Effectiveness improvements scale roughly with engine displacement-
to-vehicle weight ratio: The higher displacement-to-weight vehicles, 
operating at lower relative loads for normal driving, have the 
potential to operate in part-cylinder mode more frequently. For heavy-
duty vehicles tested and operated at loaded conditions, the power to 
weight ratio is considerably lower than the light-duty case greatly 
reducing the opportunity for ``part-cylinder'' mode and therefore was 
not considered in this rulemaking as an effective technology for heavy-
duty pickup truck and van applications.
(v) Stoichiometric Gasoline Direct Injection
    SGDI engines inject fuel at high pressure directly into the 
combustion chamber (rather than the intake port in port fuel 
injection). SGDI requires changes to the injector design, an additional 
high pressure fuel pump, new fuel rails to handle the higher fuel 
pressures and changes to the cylinder head and piston crown design. 
Direct injection of the fuel into the cylinder improves cooling of the 
air/fuel charge within the cylinder, which allows for higher 
compression ratios and increased thermodynamic efficiency without the 
onset of combustion knock. Recent injector design advances, improved 
electronic engine management systems and the introduction of multiple 
injection events per cylinder firing cycle promote better mixing of the 
air and fuel, enhance combustion rates, increase residual exhaust gas 
tolerance and improve cold start emissions. SGDI engines achieve higher 
power density and match well with other technologies, such as boosting 
and variable valvetrain designs.
    Several manufacturers have recently introduced vehicles with SGDI 
engines, including GM and Ford and have announced their plans to 
increase dramatically the number of SGDI engines in their portfolios.
    The light-duty 2012-2016 MY vehicle rule estimated the range of 1 
to 2 percent for SGDI. NHTSA and EPA reviewed this estimate for 
purposes of the NPRM, and continue to find it accurate.
    Consistent with the light-duty rule, NHTSA and EPA cost estimates 
for SGDI take into account the changes required to the engine hardware, 
engine electronic controls, ancillary and NVH mitigation systems. 
Through contacts with industry NVH suppliers, and manufacturer press 
releases, the agencies believe that the NVH treatments will be limited 
to the mitigation of fuel system noise, specifically from the injectors 
and the fuel lines. For this analysis, the agencies have estimated the 
costs at $481 (2009$) in the 2014 model year. Flat-portion of the curve 
learning is applied to this technology. This technology was considered 
for gasoline engines only, as diesel engines already employ direct 
injection.
(b) Diesel Engine Technologies
    Diesel engines have several characteristics that give them superior 
fuel efficiency compared to conventional gasoline, spark-ignited 
engines. Pumping losses are much lower due to lack of (or greatly 
reduced) throttling. The diesel combustion cycle operates at a higher 
compression ratio, with a very lean air/fuel mixture, and turbocharged 
light-duty diesels typically achieve much higher torque levels at lower 
engine speeds than equivalent-displacement naturally-aspirated gasoline 
engines. Additionally, diesel fuel has a higher energy content per 
gallon.\256\ However, diesel fuel also has a higher carbon to hydrogen 
ratio, which increases the amount of CO2 emitted per gallon 
of fuel used by approximately 15 percent over a gallon of gasoline.
---------------------------------------------------------------------------

    \256\ Burning one gallon of diesel fuel produces about 15 
percent more carbon dioxide than gasoline due to the higher density 
and carbon to hydrogen ratio.
---------------------------------------------------------------------------

    Based on confidential business information and the 2010 NAS Report, 
two major areas of diesel engine design will be improved during the 
2014-2018 time frame. These areas include aftertreatment improvements 
and a broad range of engine improvements.
(i) Aftertreatment Improvements
    The HD diesel pickup and van segment has largely adopted the SCR 
type of aftertreatment system to comply with criteria pollutant 
emission standards. As the experience base for SCR expands over the 
next few years, many improvements in this aftertreatment system such as 
construction of the catalyst, thermal management, and reductant 
optimization will result in a significant reduction in the amount of 
fuel used in the process. This technology was not considered in the 
light-duty rule. Based on confidential business information,

[[Page 57224]]

EPA and NHTSA estimate the reduction in CO2 as a result of 
these improvements at 3 to 5 percent.
    The agencies have estimated the cost of this technology at $25 for 
each percentage improvement in fuel consumption. This estimate is based 
on the agencies' belief that this technology is, in fact, a very cost 
effective approach to improving fuel consumption. As such, $25 per 
percent improvement is considered a reasonable cost. This cost would 
cover the engineering and test cell related costs necessary to develop 
and implement the improved control strategies that would allow for the 
improvements in fuel consumption. Importantly, the engineering work 
involved would be expected to result in cost savings to the 
aftertreatment and control hardware (lower platinum group metal 
loadings, lower reductant dosing rates, etc.). Those savings are 
considered to be included in the $25 per percent estimate described 
here. Given the 4 percent average expected improvement in fuel 
consumption results in an estimated cost of $119 (2009$) for a 2014 
model year truck or van. This estimate includes a low complexity ICM of 
1.24 and flat-portion of the curve learning from 2012 forward.
(ii) Engine Improvements
    Diesel engines in the HD pickup and van segment are expected to 
have several improvements in their base design in the 2014-2018 time 
frame. These improvements include items such as improved combustion 
management, optimal turbocharger design, and improved thermal 
management. This technology was not considered in the light-duty rule. 
Based on confidential business information, EPA and NHTSA estimate the 
reduction in CO2 as a result of these improvements at 4 to 6 
percent.
    The cost for this technology includes costs associated with low 
temperature exhaust gas recirculation, improved turbochargers and 
improvements to other systems and components. These costs are 
considered collectively in our costing analysis and termed ``diesel 
engine improvements.'' The agencies have estimated the cost of diesel 
engine improvements at $148 based on the cost estimates for several 
individual technologies. Specifically, the direct manufacturing costs 
we have estimated are: improved cylinder head, $9; turbo efficiency 
improvements, $16; EGR cooler improvements, $3; higher pressure fuel 
rail, $10; improved fuel injectors, $13; improved pistons, $2; and 
reduced valve train friction, $95. All values are in 2009 dollars and 
are applicable in the 2014 MY. Applying a low complexity ICM of 1.24 
results in a cost of $184 (2009$) applicable in the 2014 MY. We 
consider flat-portion of the curve learning to be appropriate for these 
technologies.
(c) Transmission Technologies
    NHTSA and EPA have also reviewed the transmission technology 
estimates used in the light-duty rule. In doing so, NHTSA and EPA 
considered or reconsidered all available sources and updated the 
estimates as appropriate. The section below describes each of the 
transmission technologies considered for the final standards.
(i) Improved Automatic Transmission Control (Aggressive Shift Logic and 
Early Torque Converter Lockup)
    Calibrating the transmission shift schedule to upshift earlier and 
quicker, and to lock-up or partially lock-up the torque converter under 
a broader range of operating conditions can reduce fuel consumption and 
CO2 emissions. However, this operation can result in a 
perceptible degradation in NVH. The degree to which NVH can be degraded 
before it becomes noticeable to the driver is strongly influenced by 
characteristics of the vehicle, and although it is somewhat subjective, 
it always places a limit on how much fuel consumption can be improved 
by transmission control changes. Given that the Aggressive Shift Logic 
and Early Torque Converter Lockup are best optimized simultaneously due 
to the fact that adding both of them primarily requires only minor 
modifications to the transmission or calibration software, these two 
technologies are combined in the modeling. We consider these 
technologies to be present in the baseline, since 6-speed automatic 
transmissions are installed in the majority of Class 2b and 3 trucks in 
the 2010 model year time frame.
(ii) Automatic 6- and 8-Speed Transmissions
    Manufacturers can also choose to replace 4- 5- and 6-speed 
automatic transmissions with 8-speed automatic transmissions. 
Additional ratios allow for further optimization of engine operation 
over a wider range of conditions, but this is subject to diminishing 
returns as the number of speeds increases. As additional planetary gear 
sets are added (which may be necessary in some cases to achieve the 
higher number of ratios), additional weight and friction are 
introduced. Also, the additional shifting of such a transmission can be 
perceived as bothersome or busy to some consumers, so manufacturers 
need to develop strategies for smooth shifts. Some manufacturers are 
replacing 4- and 5-speed automatics with 6-speed automatics already, 
and 7- and 8-speed automatics have entered production in light-duty 
vehicles, albeit in lower-volume applications in luxury and performance 
oriented cars.
    As discussed in the light-duty rule, confidential manufacturer data 
projected that 6-speed transmissions could incrementally reduce fuel 
consumption by 0 to 5 percent from a 4-speed automatic transmission, 
while an 8-speed transmission could incrementally reduce fuel 
consumption by up to 6 percent from a 4-speed automatic transmission. 
GM has publicly claimed a fuel economy improvement of up to 4 percent 
for its new 6-speed automatic transmissions.\257\
---------------------------------------------------------------------------

    \257\ General Motors, news release, ``From Hybrids to Six-
Speeds, Direct Injection And More, GM's 2008 Global Powertrain 
Lineup Provides More Miles with Less Fuel'' (released Mar. 6, 2007). 
Available at http:// www.gm.com/ experience/ fuel-- economy/ news/ 
2007/ adv-- engines/ 2008- powertrain- lineup- 082707.jsp (last 
accessed Sept. 18, 2008).
---------------------------------------------------------------------------

    NHTSA and EPA reviewed and revised these effectiveness estimates 
based on actual usage statistics and testing methods for these vehicles 
along with confidential business information. When combined with 
improved automatic transmission control, the agencies estimate the 
effectiveness for a conversion from a 4- to a 6-speed transmission to 
be 5.3 percent and a conversion from a 6- to 8-speed transmission to be 
1.7 percent. While 8-speed transmissions were not considered in the 
light-duty 2012-2016 MY vehicle rule, they are considered as a 
technology of choice for this analysis in that manufacturers are 
expected to upgrade the 6-speed automatic transmissions being 
implemented today with 8-speed automatic transmissions in the 2014-2018 
time frame. We are estimating the cost of an 8-speed automatic 
transmission at $281 (2009$) relative to a 6-speed automatic 
transmission in the 2014 model year. This estimate is based from the 
2010 NAS Report and we have applied a low complexity ICM of 1.24 and 
flat-portion of the curve learning. This technology applies to both 
gasoline and diesel pickup trucks and vans.
(d) Electrification/Accessory Technologies
(i) Electrical Power Steering or Electrohydraulic Power Steering
    Electric power steering (EPS) or Electrohydraulic power steering 
(EHPS) provides a potential reduction in CO2 emissions and 
fuel consumption over

[[Page 57225]]

hydraulic power steering because of reduced overall accessory loads. 
This eliminates the parasitic losses associated with belt-driven power 
steering pumps which consistently draw load from the engine to pump 
hydraulic fluid through the steering actuation systems even when the 
wheels are not being turned. EPS is an enabler for all vehicle 
hybridization technologies since it provides power steering when the 
engine is off. EPS may be implemented on most vehicles with a standard 
12V system. Some heavier vehicles may require a higher voltage system 
which may add cost and complexity.
    The light-duty rule estimated a one to two percent effectiveness 
based on the 2002 NAS report for light-duty vehicle technologies, a 
Sierra Research report, and confidential manufacturer data. NHTSA and 
EPA reviewed these effectiveness estimates and found them to be 
accurate, thus they have been retained for purposes of this NPRM.
    NHTSA and EPA adjusted the EPS cost for the current rulemaking 
based on a review of the specification of the system. Adjustments were 
made to include potentially higher voltage or heavier duty system 
operation for HD pickups and vans. Accordingly, higher costs were 
estimated for systems with higher capability. After accounting for the 
differences in system capability and applying the ICM markup of low 
complexity technology of 1.24, the estimated costs are $115 for a MY 
2014 truck or van (2009$). As EPS systems are in widespread usage 
today, flat-portion of the curve learning is deemed applicable. EHPS 
systems are considered to be of equal cost and both are considered 
applicable to gasoline and diesel engines.
(ii) Improved Accessories
    The accessories on an engine, including the alternator, coolant and 
oil pumps are traditionally mechanically-driven. A reduction in 
CO2 emissions and fuel consumption can be realized by 
driving the pumping accessories electrically, and only when needed 
(``on-demand''). Alternator improvements include internal changes 
resulting in lower mechanical and electrical losses combined with 
control logic that charges the battery at more efficient voltage levels 
and during conditions of available kinetic energy from the vehicle 
which would normally be wasted energy such as braking during vehicle 
decelerations.
    Electric water pumps and electric fans can provide better control 
of engine cooling. For example, coolant flow from an electric water 
pump can be reduced and the radiator fan can be shut off during engine 
warm-up or cold ambient temperature conditions which will reduce warm-
up time, reduce warm-up fuel enrichment, and reduce parasitic losses.
    Indirect benefit may be obtained by reducing the flow from the 
water pump electrically during the engine warm-up period, allowing the 
engine to heat more rapidly and thereby reducing the fuel enrichment 
needed during cold starting of the engine. Further benefit may be 
obtained when electrification is combined with an improved, higher 
efficiency engine alternator. Intelligent cooling can more easily be 
applied to vehicles that do not typically carry heavy payloads, so 
larger vehicles with towing capacity present a challenge, as these 
vehicles have high cooling fan loads.\258\
---------------------------------------------------------------------------

    \258\ In the CAFE model, improved accessories refer solely to 
improved engine cooling. However, EPA has included a high efficiency 
alternator in this category, as well as improvements to the cooling 
system.
---------------------------------------------------------------------------

    The agencies considered whether to include electric oil pump 
technology for the rulemaking. Because it is necessary to operate the 
oil pump any time the engine is running, electric oil pump technology 
has insignificant effect on efficiency. Therefore, the agencies decided 
to not include electric oil pump technology.
    NHTSA and EPA jointly reviewed the estimates of 1 to 2 percent 
effectiveness estimates used in the light-duty rule and found them to 
be accurate for Improved Electrical Accessories. Consistent with the 
light-duty rule, the agencies have estimated the cost of this 
technology at $93 (2009$) including a low complexity ICM of 1.24. This 
cost is applicable in the 2014 model year. Improved accessory systems 
are in production currently and thus flat-portion of the curve learning 
is applied. This technology was considered for diesel pickup trucks and 
vans only.
(e) Vehicle Technologies
(i) Mass Reduction
    Reducing a vehicle's mass, or down-weighting the vehicle, decreases 
fuel consumption by reducing the energy demand needed to overcome 
forces resisting motion, and rolling resistance. Manufacturers employ a 
systematic approach to mass reduction, where the net mass reduction is 
the addition of a direct component or system mass reduction plus the 
additional mass reduction taken from indirect ancillary systems and 
components, as a result of full vehicle optimization, effectively 
compounding or obtaining a secondary mass reduction from a primary mass 
reduction. For example, use of a smaller, lighter engine with lower 
torque-output subsequently allows the use of a smaller, lighter-weight 
transmission and drive line components. Likewise, the compounded weight 
reductions of the body, engine and drivetrain reduce stresses on the 
suspension components, steering components, wheels, tires and brakes, 
allowing further reductions in the mass of these subsystems. The 
reductions in unsprung masses such as brakes, control arms, wheels and 
tires further reduce stresses in the suspension mounting points. This 
produces a compounding effect of mass reductions.
    Estimates of the synergistic effects of mass reduction and the 
compounding effect that occurs along with it can vary significantly 
from one report to another. For example, in discussing its estimate, an 
Auto-Steel Partnership report states that ``These secondary mass 
changes can be considerable--estimated at an additional 0.7 to 1.8 
times the initial mass change.'' \259\ This means for each one pound 
reduction in a primary component, up to 1.8 pounds can be reduced from 
other structures in the vehicle (i.e., a 180 percent factor). The 
report also discusses that a primary variable in the realized secondary 
weight reduction is whether or not the powertrain components can be 
included in the mass reduction effort, with the lower end estimates 
being applicable when powertrain elements are unavailable for mass 
reduction. However, another report by the Aluminum Association, which 
primarily focuses on the use of aluminum as an alternative material for 
steel, estimated a factor of 64 percent for secondary mass reduction 
even though some powertrain elements were considered in the 
analysis.\260\ That report also notes that typical values for this 
factor vary from 50 to 100 percent. Although there is a wide variation 
in stated estimates, synergistic mass reductions do exist, and the 
effects result in tangible mass reductions. Mass reductions in a single 
vehicle component, for example a door side

[[Page 57226]]

impact/intrusion system, may actually result in a significantly higher 
weight savings in the total vehicle, depending on how well the 
manufacturer integrates the modification into the overall vehicle 
design. Accordingly, care must be taken when reviewing reports on 
weight reduction methods and practices to ascertain if compounding 
effects have been considered or not.
---------------------------------------------------------------------------

    \259\ ``Preliminary Vehicle Mass Estimation Using Empirical 
Subsystem Influence Coefficients,'' Malen, D.E., Reddy, K. Auto-
Steel Partnership Report, May 2007, Docket EPA-HQ-OAR-2009-0472-
0169. Accessed on the Internet on May 30, 2009 at: http://www.a-sp.org/database/custom/Mass%20Compounding%20-%20Final%20Report.pdf.
    \260\ ``Benefit Analysis: Use of Aluminum Structures in 
Conjunction with Alternative Powertrain Technologies in 
Automobiles,'' Bull, M. Chavali, R., Mascarin, A., Aluminum 
Association Research Report, May 2008, Docket EPA-HQ-OAR-2009-0472-
0168. Accessed on the Internet on April 30, 2009 at: http://www.autoaluminum.org/downloads/IBIS-Powertrain-Study.pdf.
---------------------------------------------------------------------------

    Mass reduction is broadly applicable across all vehicle subsystems 
including the engine, exhaust system, transmission, chassis, 
suspension, brakes, body, closure panels, glazing, seats and other 
interior components, engine cooling systems and HVAC systems. It is 
estimated that up to 1.25 kilograms of secondary weight savings can be 
achieved for every kilogram of weight saved on a light-duty vehicle 
when all subsystems are redesigned to take into account the initial 
primary weight savings.261 262
---------------------------------------------------------------------------

    \261\ ``Future Generation Passenger Compartment-Validation (ASP 
241)'' Villano, P.J., Shaw, J.R., Polewarczyk, J., Morgans, S., 
Carpenter, J.A., Yocum, A.D., in ``Lightweighting Materials--FY 2008 
Progress Report,'' U.S. Department of Energy, Office of Energy 
Efficiency and Renewable Energy, Vehicle Technologies Program, May 
2009, Docket EPA-HQ-OAR-2009-0472-0190.
    \262\ ``Preliminary Vehicle Mass Estimation Using Empirical 
Subsystem Influence Coefficients,'' Malen, D.E., Reddy, K. Auto-
Steel Partnership Report, May 2007, Docket EPA-HQ-OAR-2009-0472-
0169. Accessed on the Internet on May 30, 2009 at: http://www.a-sp.org/database/custom/Mass%20Compounding%20-%20Final%20Report.pdf.
---------------------------------------------------------------------------

    Mass reduction can be accomplished by proven methods such as:
     Smart Design: Computer aided engineering (CAE) tools can 
be used to better optimize load paths within structures by reducing 
stresses and bending moments applied to structures. This allows better 
optimization of the sectional thicknesses of structural components to 
reduce mass while maintaining or improving the function of the 
component. Smart designs also integrate separate parts in a manner that 
reduces mass by combining functions or the reduced use of separate 
fasteners. In addition, some ``body on frame'' vehicles are redesigned 
with a lighter ``unibody'' construction.
     Material Substitution: Substitution of lower density and/
or higher strength materials into a design in a manner that preserves 
or improves the function of the component. This includes substitution 
of high-strength steels, aluminum, magnesium or composite materials for 
components currently fabricated from mild steel.
     Reduced Powertrain Requirements: Reducing vehicle weight 
sufficiently allows for the use of a smaller, lighter and more 
efficient engine while maintaining or increasing performance. 
Approximately half of the reduction is due to these reduced powertrain 
output requirements from reduced engine power output and/or 
displacement, changes to transmission and final drive gear ratios. The 
subsequent reduced rotating mass (e.g., transmission, driveshafts/
halfshafts, wheels and tires) via weight and/or size reduction of 
components are made possible by reduced torque output requirements.
     Automotive companies have largely used weight savings in 
some vehicle subsystems to offset or mitigate weight gains in other 
subsystems from increased feature content (sound insulation, 
entertainment systems, improved climate control, panoramic roof, etc.).
     Lightweight designs have also been used to improve vehicle 
performance parameters by increased acceleration performance or 
superior vehicle handling and braking.
    Many manufacturers have already announced final future products 
plans reducing the weight of a vehicle body through the use of high 
strength steel body-in-white, composite body panels, magnesium alloy 
front and rear energy absorbing structures reducing vehicle weight 
sufficiently to allow a smaller, lighter and more efficient engine. 
Nissan will be reducing average vehicle curb weight by 15 percent by 
2015.\263\ Ford has identified weight reductions of 250 to 750 lb per 
vehicle as part of its implementation of known technology within its 
sustainability strategy between 2011 and 2020.\264\ Mazda plans to 
reduce vehicle weight by 220 pounds per vehicle or more as models are 
redesigned.265 266 Ducker International estimates that the 
average curb weight of light-duty vehicle fleet will decrease 
approximately 2.8 percent from 2009 to 2015 and approximately 6.5 
percent from 2009 to 2020 via changes in automotive materials and 
increased change-over from previously used body-on-frame automobile and 
light-truck designs to newer unibody designs.\263\ While the 
opportunity for mass reductions available to the light-duty fleet may 
not in all cases be applied directly to the heavy-duty fleet due to the 
different designs for the expected duty cycles of a ``work'' vehicle, 
mass reductions are still available particularly to areas unrelated to 
the components and systems necessary for the work vehicle aspects.
---------------------------------------------------------------------------

    \263\ ``Lighten Up!,'' Brooke, L., Evans, H. Automotive 
Engineering International, Vol. 117, No. 3, March 2009.
    \264\ ``2008/9 Blueprint for Sustainability,'' Ford Motor 
Company. Available at: http://www.ford.com/go/sustainability (last 
accessed February 8, 2010).
    \265\ ``Mazda to cut vehicle fuel consumption 30 percent by 
2015,'' Mazda press release, June 23, 2009. Available at: http://www.mazda.com/publicity/release/2008/200806/080623.html (last 
accessed February 8, 2010).
    \266\ ``Mazda: Don't believe hot air being emitted by hybrid 
hype,'' Greimel, H. Automotive News, March 30, 2009.
---------------------------------------------------------------------------

    Due to the payload and towing requirements of these heavy-duty 
vehicles, engine downsizing was not considered in the estimates for 
CO2 reduction in the area of mass reduction and material 
substitution. NHTSA and EPA estimate that a 3 percent mass reduction 
with no engine downsizing results in a 1 percent reduction in fuel 
consumption. In addition, a 5 and 10 percent mass reduction with no 
engine downsizing result in an estimated CO2 reduction of 
1.6 and 3.2 percent respectively. These effectiveness values are 50 
percent of the light-duty rule values due to the elimination of engine 
downsizing for this class of vehicle.
    In the NPRM, EPA and NHTSA relied on three studies to estimate the 
cost of vehicle mass reduction. The agencies used a value of $1.32 per 
pound of mass reduction that was derived from a 2002 National Academy 
of Sciences study, a 2008 Sierra Research report, and a 2008 MIT study. 
The cost was estimated to be constant, independent of the level of mass 
reduction.
    The agencies along with the California Air Resources Board (CARB) 
have recently completed work on an Interim Joint Technical Assessment 
Report (TAR) that considers light-duty GHG and fuel economy standards 
for model years 2017 through 2025 and have continued this work to 
support the light-duty vehicle NPRM, which is expected to be issued 
this fall. Based on new information from various industry and 
literature sources, the TAR modified the mass reduction/cost 
relationship used in the light-duty 2012-2016 MY vehicle rule to begin 
at the origin (zero cost at zero percent mass reduction) and to have 
increasing cost with increasing mass reduction.\267\ The resulting 
analysis showed costs for 5 percent mass reduction on light-duty 
vehicles to be near zero or cost parity.
---------------------------------------------------------------------------

    \267\ ``Interim Joint Technical Assessment Report: Light-Duty 
Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel 
Economy Standards for Model Years 2017-2025;'' September 2010; 
available at http://epa.gov/otaq/climate/regulations/ldv-ghg-tar.pdf 
and in the docket for this rule.
---------------------------------------------------------------------------

    In the proposal for heavy-duty vehicles, we estimated mass 
reduction costs based on the 2012-2016 light-duty analysis without 
accounting for the new work completed in the Interim Joint Technical 
Assessment and additional

[[Page 57227]]

work the agencies have considered for the upcoming light-duty vehicle 
NPRM. Since the heavy-duty vehicle proposal, the agencies have been 
able to consider updated cost estimates in the context of both light-
duty and heavy-duty vehicle bodies of work. While the agencies intend 
to discuss the additional work for the light-duty NPRM in much more 
detail in the documents for that rulemaking, we think it appropriate to 
explain here that after having considered a number of additional and 
highly-varying sources, the agencies believe that the cost estimates 
used in the TAR may have been lower than would be reasonable for HD 
pickups and vans, given their different and work-related uses and thus 
different construction as compared to the light-duty vehicles evaluated 
in the TAR. We do not believe that all of the weight reduction 
opportunities for light-duty vehicles can be applied to heavy-duty 
trucks. However, we do believe reductions in the following components 
and systems can be found that do not affect the payload and towing 
requirements of these heavy-duty vehicles: Body, closure panels, 
glazing, seats and other interior components, engine cooling systems 
and HVAC systems.
    The agencies have reviewed and considered many different mass 
reduction studies during the technical assessment for the heavy-duty 
vehicle GHG and fuel efficiency rulemaking. The agencies found that 
many of the studies on this topic vary considerably in their rigor, 
transparency, and applicability to the regulatory assessment. Having 
considered a variety of options, the agencies for this heavy-duty 
analysis have been unable to come up with a way to quantitatively 
evaluate the available studies. Therefore, the agencies have chosen a 
value within the range of the available studies that the agencies 
believe is reasonable. The studies and manufacturers' confidential 
business information relied upon in determining the final mass 
reduction costs are summarized in Figure 2.1, Section 2.3.6 of the RIA. 
Each study relied upon by the agencies in this determination has also 
been placed in the agencies' respective dockets. See NHTSA-2010-0079; 
EPA-HQ-0AR-2010-0162.
    The agencies note that the NAS 2010 study provided estimates of 
mass reduction costs, but the agencies did not consider using the NAS 
2010 study as the single source of mass reduction cost estimates 
because the NAS 2010 estimates were not based on literature reports 
that focused on trucks or were necessarily appropriate for MD/HD 
vehicles, and also because a variety of newer and more rigorous studies 
were available to the agencies than those relied upon by the NAS in 
developing its estimates. We note, however, that for a 5 percent 
reduction in mass, the NAS 2010 report estimates a per pound cost of 
mass reduction of $1.65.
    Thus, we are estimating the direct manufacturing costs for a 5 
percent mass reduction of a 6,000 lb vehicle at a range of $75-$90 per 
vehicle. With additional margin for uncertainty, we arrive at a direct 
manufacturing cost of $85-$100, which is roughly in the upper middle of 
the range of values that resulted from the additional and highly-
varying studies mentioned above that were considered in the agencies' 
review. We have broken this down for application to HD pickup trucks 
and vans as follows: Class 2b gasoline $85, Class 2b diesel $95, Class 
3 gasoline $90, and Class 3 diesel trucks $100. Applying the low 
complexity ICM of 1.24 results in estimated total costs for a 5 percent 
mass reduction applicable in the 2016 model year as follows: Class 2b 
gasoline $108, Class 2b diesel $121, Class 3 gasoline $115, and Class 3 
diesel trucks $127. All mass reduction costs stated here are in 2009 
dollars.
(ii) Low Rolling Resistance Tires
    Tire rolling resistance is the frictional loss associated mainly 
with the energy dissipated in the deformation of the tires under load 
and thus influences fuel efficiency and CO2 emissions. Other 
tire design characteristics (e.g., materials, construction, and tread 
design) influence durability, traction (both wet and dry grip), vehicle 
handling, and ride comfort in addition to rolling resistance. A typical 
LRR tire's attributes would include: increased tire inflation pressure, 
material changes, and tire construction with less hysteresis, geometry 
changes (e.g., reduced aspect ratios), and reduction in sidewall and 
tread deflection. These changes would generally be accompanied with 
additional changes to suspension tuning and/or suspension design.
    EPA and NHTSA estimated a 1 to 2 percent increase in effectiveness 
with a 10 percent reduction in rolling resistance, which was based on 
the 2010 NAS Report findings and consistent with the light-duty rule.
    Based on the light-duty rule and the 2010 NAS Report, the agencies 
have estimated the cost for LRR tires to be $7 per Class 2b truck or 
van, and $10 per Class 3 truck or van (both values in 2009$ and 
inclusive of a 1.24 low complexity markup).\268\ The higher cost for 
the Class 3 trucks and vans is due to the predominant use of dual rear 
tires and, thus, 6 tires per truck. Due to the commodity-based nature 
of this technology, cost reductions due to learning are not applied. 
This technology is considered applicable to both gasoline and diesel.
---------------------------------------------------------------------------

    \268\ ``Tires and Passenger Vehicle Fuel Economy,'' 
Transportation Research Board Special Report 286, National Research 
Council of the National Academies, 2006, Docket EPA-HQ-OAR-2009-
0472-0146.
---------------------------------------------------------------------------

(iii) Aerodynamic Drag Reduction
    Many factors affect a vehicle's aerodynamic drag and the resulting 
power required to move it through the air. While these factors change 
with air density and the square and cube of vehicle speed, 
respectively, the overall drag effect is determined by the product of 
its frontal area and drag coefficient, Cd. Reductions in these 
quantities can therefore reduce fuel consumption and CO2 
emissions. Although frontal areas tend to be relatively similar within 
a vehicle class (mostly due to market-competitive size requirements), 
significant variations in drag coefficient can be observed. Significant 
changes to a vehicle's aerodynamic performance may need to be 
implemented during a redesign (e.g., changes in vehicle shape). 
However, shorter-term aerodynamic reductions, with a somewhat lower 
effectiveness, may be achieved through the use of revised exterior 
components (typically at a model refresh in mid-cycle) and add-on 
devices that currently are being applied. The latter list would include 
revised front and rear fascias, modified front air dams and rear 
valances, addition of rear deck lips and underbody panels, and lower 
aerodynamic drag exterior mirrors.
    The light-duty 2012-2016 MY vehicle rule estimated that a fleet 
average of 10 to 20 percent total aerodynamic drag reduction is 
attainable which equates to incremental reductions in fuel consumption 
and CO2 emissions of 2 to 3 percent for both cars and 
trucks. These numbers are generally supported by confidential 
manufacturer data and public technical literature. For the heavy-duty 
truck category, a 5 to 10 percent total aerodynamic drag reduction was 
considered due to the different structure and use of these vehicles 
equating to incremental reductions in fuel consumption and 
CO2 emissions of 1 to 2 percent.
    Consistent with the light-duty rule, the agencies have estimated 
the cost for this technology at $58 (2009$) including a low complexity 
ICM of 1.24. This cost is applicable in the 2014 model year to

[[Page 57228]]

both gasoline and diesel pickup trucks and vans.
(3) What are the projected technology packages' effectiveness and cost?
    The assessment of the final technology effectiveness was developed 
through the use of the EPA Lumped Parameter model developed for the 
light-duty rule. Many of the technologies were common with the light-
duty assessment but the effectiveness of individual technologies was 
appropriately adjusted to match the expected effectiveness when 
implemented in a heavy-duty application. The model then uses the 
individual technology effectiveness levels but then takes into account 
technology synergies. The model is also designed to prevent double 
counting from technologies that may directly or indirectly impact the 
same physical attribute (e.g., pumping loss reductions).
    To achieve the levels of the final standards for gasoline and 
diesel powered heavy-duty vehicles, the technology packages were 
determined to generally require the technologies previously discussed 
respective to unique gasoline and diesel technologies. Although some of 
the technologies may already be implemented in a portion of heavy-duty 
vehicles, none of the technologies discussed are considered ubiquitous 
in the heavy-duty fleet. Also, as would be expected, the available test 
data shows that some vehicle models will not need the full complement 
of available technologies to achieve the final standards. Furthermore, 
many technologies can be further improved (e.g., aerodynamic 
improvements) from today's best levels, and so allow for compliance 
without needing to apply a technology that a manufacturer might deem 
less desirable.
    Technology costs for HD pickup trucks and vans are shown in Table 
III-11.

  Table III-11--Technology Costs for HD Pickup Trucks & Vans Inclusive of Indirect Cost Markups for the 2014MY
                                                     [2009$]
----------------------------------------------------------------------------------------------------------------
                                                                Class 2b     Class 2b     Class 3      Class 3
                         Technology                             gasoline      diesel      gasoline      diesel
----------------------------------------------------------------------------------------------------------------
Low friction lubes..........................................           $4           $4           $4           $4
Engine friction reduction...................................          116          N/A          116          N/A
Stoichiometric gasoline direct injection....................          481          N/A          481          N/A
Engine improvements.........................................          N/A          184          N/A          184
8s automatic transmission (increment to 6s automatic                  281          281          281          281
 transmission)..............................................
Improved accessories........................................          N/A           93          N/A           93
Low rolling resistance tires................................            7            7           10           10
Aerodynamic improvements....................................           58           58           58           58
Electric (or electro/hydraulic) power steering..............          115          115          115          115
Aftertreatment improvements.................................          N/A          119          N/A          119
Mass reduction (5%).........................................          108          121          115          127
Air conditioning............................................           21           21           21           21
    Total...................................................        1,190        1,003        1,209        1,013
                                                             ---------------------------------------------------
At 15% phase-in in 2014.....................................          179          150          180          152
----------------------------------------------------------------------------------------------------------------

(4) Reasonableness of the Final Standards
    The final standards are based on the application of the control 
technologies described in this section. These technologies are 
available within the lead time provided, as discussed in RIA Chapter 
2.3. These controls are estimated to add costs of approximately $1,048 
for MY 2018 heavy-duty pickups and vans. Reductions associated with 
these costs and technologies are considerable, estimated at a 12 
percent reduction of CO2eq emissions from the MY 2010 
baseline for gasoline engine-equipped vehicles and 17 percent for 
diesel engine equipped vehicles, estimated to result in reductions of 
18 MMT of CO2eq emissions over the lifetimes of 2014 through 
2018 MY vehicles.\269\ The reductions are cost effective, estimated at 
$90 per ton of CO2eq removed in 2030.\270\ This cost is 
consistent with the light-duty rule which was estimated at $100 per ton 
of CO2eq removed in 2020 excluding fuel savings. Moreover, 
taking into account the fuel savings associated with the program, the 
cost becomes -$230 per ton of CO2eq (i.e. a savings of $230 
per ton) in 2030. The cost of controls is fully recovered due to the 
associated fuel savings, with a payback period in the second year of 
ownership, as shown in Table VIII-9 below in Section VIII. Given the 
large, cost effective emission reductions based on use of feasible 
technologies which are available in the lead time provided, plus the 
lack of adverse impacts on vehicle safety or utility, EPA and NHTSA 
regard these final standards as appropriate and consistent with our 
respective statutory authorities under CAA section 202(a) and NHTSA's 
EISA authority under 49 U.S.C. 32902(k)(2). Based on the discussion 
above, NHTSA believes these standards are the maximum feasible under 
EISA.
---------------------------------------------------------------------------

    \269\ See Table VI-4 of this preamble.
    \270\ See Table 0-3 of this preamble.
---------------------------------------------------------------------------

(5) Alternative HD Pickup Truck and Van Standards Considered
    The agencies rejected consideration of any less stringent standards 
given that the standards adopted are feasible at reasonable cost and 
cost-effectiveness within the lead time of the program. Furthermore, as 
explained above, because the standards are premised on 100 percent 
application of available technologies during this period, the agencies 
rejected adoption of more stringent standards. The agencies have also 
explained above why the phase-in period for the standards is reasonable 
and that attempting more aggressive phase-ins would start to force 
changes outside normal redesign cycles at likely exorbitant cost.

C. Class 2b-8 Vocational Vehicles

    Vocational vehicles cover a wide variety of applications which 
influence both the body style and usage patterns. They also are built 
using a complex process, which includes additional entities such as 
body builders. These factors create special sensitivity to

[[Page 57229]]

concerns of needed lead time, as well as developing standards that do 
not interfere with vocational vehicles' utility. The agencies are 
adopting a standard for vocational vehicles for the first phase of the 
program that relies on less extensive addition of technology than do 
the other regulatory categories as well as making the chassis 
manufacturer the manufacturer subject to the standard. We intend that 
future rulemakings will consider increased stringency and possibly more 
application-specific standards. The agencies are also finalizing 
standards for the diesel and gasoline engines installed in vocational 
vehicles, similar to those discussed above for HD engines installed in 
Class 7 and 8 tractors.
(1) What technologies did the agencies consider to reduce the 
CO2 emissions and fuel consumption of vocational vehicles?
    Similar to the approach taken with tractors, the agencies evaluated 
aerodynamic, tire, idle reduction, weight reduction, hybrid powertrain, 
and engine technologies and their impact on reducing fuel consumption 
and GHG emissions. The engines used in vocational vehicles include both 
gasoline and diesel engines, thus, each type is discussed separately 
below. As explained in Section II.D.1.b, the final regulatory structure 
for heavy-duty engines separates the compression ignition (or 
``diesel'') engines into three regulatory subcategories--light heavy, 
medium heavy, and heavy heavy diesel engines--while spark ignition (or 
``gasoline'') engines are a single regulatory subcategory (an approach 
for which there was consensus in the public comments). Therefore, the 
subsequent discussion will assess each type of engine separately.
(a) Vehicle Technologies
    Vocational vehicles typically travel fewer miles than combination 
tractors. They also tend to be used in more urban locations (with 
consequent stop and start drive cycles). Therefore the average speed of 
vocational vehicles is significantly lower than combination tractors. 
This has a significant effect on the types of technologies that are 
appropriate to consider for reducing CO2 emissions and fuel 
consumption.
    The agencies considered the type of technologies for vocational 
vehicles based on the energy losses of a typical vocational vehicle. 
The technologies are similar to the ones considered for combination 
tractors. Argonne National Lab conducted an energy audit using 
simulation tools to evaluate the energy losses of vocational vehicles, 
such as a Class 6 pickup and delivery truck. Argonne found that 74 
percent of the energy losses are attributed to the engine, 13 percent 
to tires, 9 percent to aerodynamics, two percent to transmission 
losses, and the remaining four percent of losses to axles and 
accessories for a medium-duty truck traveling at 30 mph.\271\
---------------------------------------------------------------------------

    \271\ Argonne National Lab. Evaluation of Fuel Consumption 
Potential of Medium and Heavy-duty Vehicles through Modeling and 
Simulation. October 2009. Page 89.
---------------------------------------------------------------------------

    Low Rolling Resistance Tires: Tires are the second largest 
contributor to energy losses of vocational vehicles, as found in the 
energy audit conducted by Argonne National Lab (as just mentioned). The 
range of rolling resistance of tires used on vocational vehicles today 
is large. This is in part due to the fact that the competitive pressure 
to improve rolling resistance of vocational vehicle tires has been less 
than that found in the line haul tire market. In addition, the drive 
cycles typical for these applications often lead truck buyers to value 
tire traction and durability more heavily than rolling resistance. 
Therefore, the agencies concluded that a regulatory program that seeks 
to optimize tire rolling resistance in addition to traction and 
durability can bring about fuel consumption and CO2 emission 
reductions from this segment. The 2010 NAS report states that rolling 
resistance impact on fuel consumption reduces with mass of the vehicle 
and with drive cycles with more frequent starts and stops. The report 
found that the fuel consumption reduction opportunity for reduced 
rolling resistance ranged between one and three percent in the 2010 
through 2020 time frame.\272\ The agencies estimate that average 
rolling resistance from tires in 2010 model year can be reduced by 10 
percent for 50 percent of the vehicles by 2014 model year based on the 
tire development achievements over the last several years in the line 
haul truck market.
---------------------------------------------------------------------------

    \272\ See 2010 NAS Report, Note 197, page 146.
---------------------------------------------------------------------------

    Aerodynamics: The Argonne National lab work shows that aerodynamics 
has less of an impact on vocational vehicle energy losses than do 
engines or tires. In addition, the aerodynamic performance of a 
complete vehicle is significantly influenced by the body of the 
vehicle. The agencies are not regulating body builders in this phase of 
regulations for the reasons discussed in Section II. Therefore, we are 
not basing any of the final standards for vocational vehicles on 
aerodynamic improvements. Nor would aerodynamic performance be input 
into GEM to demonstrate compliance.
    Weight Reduction: NHTSA and EPA are also not basing any of the 
final vocational vehicle standards on use of vehicle weight reduction. 
Thus, vehicle mass reductions are not an input into GEM. The agencies 
are taking this approach despite comments suggesting that the agencies 
make use of weight reductions for this segment, because we are unable 
to quantify the potential impact of weight reduction on vehicle utility 
in this broad segment. Vocational vehicles serve an incredibly diverse 
range of functions. Each of these unique vehicle functions is likely to 
have its own unique tradeoff between vehicle utility and the potential 
for vehicle mass reduction. The agencies have not been able at this 
time to determine the degree to which such tradeoffs exist nor the 
specific level of the tradeoff for each unique vehicle vocation. No 
commenter provided data to inform this question. Absent this 
information, the agencies cannot at this time project the potential for 
worthwhile weight reductions from vocational vehicles.
    Drivetrain: Optimization of vehicle gearing to engine performance 
through selection of transmission gear ratios, final drive gear ratios 
and tire size can play a significant role in reducing fuel consumption 
and GHGs. Optimization of gear selection versus vehicle and engine 
speed accomplished through driver training or automated transmission 
gear selection can provide additional reductions. The 2010 NAS report 
found that the opportunities to reduce fuel consumption in heavy-duty 
vehicles due to transmission and driveline technologies in the 2015 
time frame ranged between 2 and 8 percent.\273\ Initially, the agencies 
considered reflecting transmission choices and technology in our 
standard setting process for both tractors and vocational vehicles (see 
previous discussion above on automated manual and automatic 
transmissions for tractors). We have however decided not to do so for 
the following reasons.
---------------------------------------------------------------------------

    \273\ See 2010 NAS Report, Note 197, pp 134 and 137.
---------------------------------------------------------------------------

    The primary factors that determine optimum gear selection are 
vehicle weight, vehicle aerodynamics, vehicle speed, and engine 
performance typically considered on a two dimensional map of engine 
speed and torque. For a given power demand (determined by speed, 
aerodynamics and vehicle mass) an optimum transmission and gearing 
setup will keep the engine power delivery operating at the best speed 
and torque points for highest engine

[[Page 57230]]

efficiency. Since power delivery from the engine is the product of 
speed and torque a wide range of torque and speed points can be found 
that deliver adequate power, but only a smaller subset will provide 
power with peak efficiency. Said more generally, the design goal is for 
the transmission to deliver the needed power to the vehicle while 
maintaining engine operation within the engine's ``sweet spot'' for 
most efficient operation. Absent information about vehicle mass and 
aerodynamics (which determines road load at highway speeds) it is not 
possible to optimize the selection of gear ratios for lowest fuel 
consumption. Truck and chassis manufacturers today offer a wide range 
of tire sizes, final gear ratios and transmission choices so that final 
bodybuilders can select an optimal combination given the finished 
vehicle weight, general aerodynamic characteristics and expected 
average speed. In order to set fuel efficiency and GHG standards that 
would reflect these optimizations, the agencies would need to regulate 
a wide range of small entities that are final bodybuilders, would need 
to set a large number of uniquely different standards to reflect the 
specific weight and aerodynamic differences and finally would need test 
procedures to evaluate these differences that would not themselves be 
excessively burdensome. Finally, the agencies would need the underlying 
data regarding effectively all of the vocational trucks produced today 
in order to determine the appropriate standards. Because the market is 
already motivated to reach these optimizations themselves today, 
because we have insufficient data to determine appropriate standards, 
and finally, because we believe the testing burden would be 
unjustifiably high, we are not finalizing to reflect transmission and 
gear ratio optimization in our GEM or in our standard setting.
    Some commenters suggested that the agencies predicate the 
vocational vehicle standard on the use of specific transmission 
technologies for example automated manual transmissions believing that 
these mechanically more efficient designs would inherently provide 
better fuel efficiency and lower greenhouse gas emissions than 
conventional torque convertor automatic transmission designs. However 
as discussed above the agencies believe that the small mechanical 
efficiency differences between these transmission designs are 
relatively insignificant in the context of the dominant impact of 
proper gear ratio selection in determining a vehicle's overall 
performance. In many cases, the mechanically more efficient design may 
prove less effective in use if other aspects of vehicle performance 
(such a vehicle launch under load) compromise the selection of gear 
ratios. This somewhat surprising outcome can be seen most readily by 
looking at modern passenger cars where mechanically less efficient 
torque converter automatic models often produce equal or better fuel 
economy when compared to the more mechanically efficient manual 
transmission versions of the same vehicles. Given this reality, we do 
not believe it would be appropriate to base the vocational truck 
standard on the use of a particular transmission technology. In the 
future, if we develop a complete vehicle chassis test approach to 
regulating this segment, we would then be able to incorporate 
transmission performance as we already do for the heavy-duty pickup 
truck and van segment.
    Idle Reduction: Episodic idling by vocational vehicles occurs 
during the workday, unlike the overnight idling of combination tractors 
(see discussion in Section III.A.2.a). Vocational vehicle idling can be 
divided into two typical types. The first type is idling while 
waiting--such as during a pickup or delivery. This type of idling can 
be reduced through automatic engine shut-offs. The second type of 
idling is to accomplish PTO operation, such as compacting garbage or 
operating a bucket. The agencies have found only one study that 
quantifies the emissions due to idling conducted by Argonne National 
Lab based on 2002 VIUS data.\274\ EPA conducted a work assignment to 
assist in characterizing PTO operations. The study of a utility truck 
used in two different environments (rural and urban) and a refuse 
hauler found that the PTO operated on average 28 percent of time 
relative to the total time spent driving and idling.\275\ The use of 
hybrid powertrains to reduce idling is discussed below.
---------------------------------------------------------------------------

    \274\ Gaines, Linda, A. Vyas, J. Anderson (Argonne National 
Laboratory). Estimation of Fuel Use by Idling Commercial Trucks. 
January 2006.
    \275\ Southwest Research Institute. Power Take Off Cycle 
Development and Testing. 2010. Docket EPA-HQ-OAR-2010-0162-3335.
---------------------------------------------------------------------------

    Hybrid Powertrains: Several types of vocational vehicles are well 
suited for hybrid powertrains. Vehicles such as utility or bucket 
trucks, delivery vehicles, refuse haulers, and buses have operational 
usage patterns with either a significant amount of stop-and-go activity 
or spend a large portion of their operating hours idling the main 
engine to operate a PTO unit. The industry is currently developing many 
variations of hybrid powertrain systems. The hybrids developed to date 
have seen fuel consumption and CO2 emissions reductions 
between 20 and 50 percent in the field. However, there are still some 
key issues that are restricting the penetration of hybrids, including 
overall system cost, battery technology, and lack of cost-effective 
electrified accessories. We have not predicated the standards based on 
the use of hybrids reflecting the still nascent level of technology 
development and the very small fraction of vehicle sales they would be 
expected to account for in this time frame--on the order of only a 
percent or two. Were we to overestimate the number of hybrids that 
could be produced, we would set a standard that is not feasible. We 
believe that it is more appropriate given the status of technology 
development and our hopes for future advancements in hybrid 
technologies to encourage their production through incentives. Thus, to 
create an incentive for early introduction of hybrid powertrains into 
the vocational vehicle fleet, the agencies are adopting the proposed 
advanced technology credits if hybrid powertrains are used as a 
technology to meet the vocational vehicle standard (or any other 
vehicle standard), as described in Section IV.
(b) Gasoline Engine Technologies
    The gasoline (or spark ignited) engines certified and sold as loose 
engines into the heavy-duty truck market are typically large V8 and V10 
engines produced by General Motors and Ford. The basic architecture of 
these engines is the same as the versions used in the heavy-duty pickup 
trucks and vans. Therefore, the technologies analyzed by the agencies 
mirror the gasoline engine technologies used in the heavy-duty pickup 
truck analysis in Section III.B above.
    Building on the technical analysis underlying the light-duty 2012-
2016 MY vehicle rule, the agencies took a fresh look at technology 
effectiveness values for purposes of this analysis using as a starting 
point the estimates from that rule. The agencies then considered the 
impact of test procedures (such as higher test weight of HD pickup 
trucks and vans) on the effectiveness estimates. The agencies also 
considered other sources such as the 2010 NAS Report, recent CAFE 
compliance data, and confidential manufacturer estimates of technology 
effectiveness. NHTSA and EPA engineers reviewed effectiveness 
information from the multiple sources for each technology and ensured 
that such effectiveness estimates were based

[[Page 57231]]

on technology hardware consistent with the BOM components used to 
estimate costs.
    The agencies note that the effectiveness values estimated for the 
technologies may represent average values, and do not reflect the 
potentially-limitless spectrum of possible values that could result 
from adding the technology to different vehicles. For example, while 
the agencies have estimated an effectiveness of 0.5 percent for low 
friction lubricants, each vehicle could have a unique effectiveness 
estimate depending on the baseline vehicle's oil viscosity rating. For 
purposes of this final rulemaking, NHTSA and EPA believe that employing 
average values for technology effectiveness estimates is an appropriate 
way of recognizing the potential variation in the specific benefits 
that individual manufacturers (and individual engines) might obtain 
from adding a fuel-saving technology.
    Baseline Engine: Similar to the gasoline engine used as the 
baseline in the light-duty rule, the agencies assumed the baseline 
engine in this segment to be a naturally aspirated, overhead valve V8 
engine.\276\ The agencies did not receive any comments regarding the 
baseline engine assumptions in the proposal. The following discussion 
of effectiveness is generally in comparison to 2010 baseline engine 
performance.
---------------------------------------------------------------------------

    \276\ The agencies note that baseline did not include coupled 
cam phasing for loose HD gasoline engines. The HD loose engines are 
slightly different than the ones used in the HD pickup trucks. They 
tend to be the older versions of the same engine.
---------------------------------------------------------------------------

    For the final rulemaking, the agencies considered the same set of 
technologies for loose gasoline engines at proposal. The agencies 
received comments which suggested that the agencies consider 
electrification of accessories to reduce the fuel consumption and 
CO2 emissions from heavy-duty gasoline engines. 
Electrification may result in a reduction in power demand, because 
electrically powered accessories (such as the air compressor or power 
steering) operate only when needed if they are electrically powered, 
but they impose a parasitic demand all the time if they are engine 
driven. In other cases, such as cooling fans or an engine's water pump, 
electric power allows the accessory to run at speeds independent of 
engine speed, which can reduce power consumption. However, technologies 
such as these improvements to accessories are not demonstrated using 
the engine dynamometer test procedures being adopted in this final rule 
because those systems are not installed on the engine during the 
testing. Thus, the technologies the agencies considered include the 
following:
    Engine Friction Reduction: In addition to low friction lubricants, 
manufacturers can also reduce friction and improve fuel consumption by 
improving the design of engine components and subsystems. Examples 
include improvements in low-tension piston rings, piston skirt design, 
roller cam followers, improved crankshaft design and bearings, material 
coatings, material substitution, more optimal thermal management, and 
piston and cylinder surface treatments. The 2010 NAS, NESCCAF \277\ and 
EEA \278\ reports as well as confidential manufacturer data used in the 
light-duty vehicle rulemaking suggested a range of effectiveness for 
engine friction reduction to be between 1 to 3 percent. NHTSA and EPA 
continue to believe that this range is accurate.
---------------------------------------------------------------------------

    \277\ Northeast States Center for a Clean Air Future. ``Reducing 
Greenhouse Gas Emissions from Light-Duty Motor Vehicles.'' September 
2004.
    \278\ Energy and Environmental Analysis, Inc. ``Technology to 
Improve the Fuel Economy of Light Duty Trucks to 2015.'' May 2006.
---------------------------------------------------------------------------

    Coupled Cam Phasing: Valvetrains with coupled (or coordinated) cam 
phasing can modify the timing of both the inlet valves and the exhaust 
valves an equal amount by phasing the camshaft of a single overhead cam 
engine or an overhead valve engine. Based on the light-duty 2012-2016 
MY vehicle rule, previously-received confidential manufacturer data, 
and the NESCCAF report, NHTSA and EPA estimated the effectiveness of 
couple cam phasing CCP to be between 1 and 4 percent. NHTSA and EPA 
reviewed this estimate for purposes of the NPRM, and continue to find 
it accurate.
    Cylinder Deactivation: In conventional spark-ignited engines 
throttling the airflow controls engine torque output. At partial loads, 
efficiency can be improved by using cylinder deactivation instead of 
throttling. Cylinder deactivation can improve engine efficiency by 
disabling or deactivating (usually) half of the cylinders when the load 
is less than half of the engine's total torque capability--the valves 
are kept closed, and no fuel is injected--as a result, the trapped air 
within the deactivated cylinders is simply compressed and expanded as 
an air spring, with reduced friction and heat losses. The active 
cylinders combust at almost double the load required if all of the 
cylinders were operating. Pumping losses are significantly reduced as 
long as the engine is operated in this ``part cylinder'' mode. 
Effectiveness improvements scale roughly with engine displacement-to-
vehicle weight ratio: The higher displacement-to-weight vehicles, 
operating at lower relative loads for normal driving, have the 
potential to operate in part-cylinder mode more frequently. Cylinder 
deactivation is less effective on heavily-loaded vehicles because they 
require more power and spend less time in areas of operation where only 
partial power is required. The technology also requires proper 
integration into the vehicles which is difficult in the vocational 
vehicle segment where often the engine is sold to a chassis 
manufacturer or body builder without knowing the type of transmission 
or axle used in the vehicle or the precise duty cycle of the vehicle. 
The cylinder deactivation requires fine tuning of the calibration as 
the engine moves into and out of deactivation mode to achieve 
acceptable NVH. Additionally, cylinder deactivation would be difficult 
to apply to vehicles with a manual transmission because it requires 
careful gear change control. NHTSA and EPA adjusted the 2012-16 MY 
light-duty rule estimates using updated power to weight ratings of 
heavy-duty trucks and confidential business information and downwardly 
adjusted the effectiveness to 0 to 3 percent for these vehicles to 
reflect the differences in drive cycle and operational opportunities 
compared to light-duty vehicles. Because of the complexities associated 
with integrating cylinder deactivation in a non-integrated vehicle 
assembly process and the low effectiveness of the technology, the 
agencies did not include cylinder deactivation in the final gasoline 
engine technology package.
    Stoichiometric gasoline direct injection: SGDI (also known as 
spark-ignition direct injection engines) inject fuel at high pressure 
directly into the combustion chamber (rather than the intake port in 
port fuel injection). Direct injection of the fuel into the cylinder 
improves cooling of the air/fuel charge within the cylinder, which 
allows for higher compression ratios and increased thermodynamic 
efficiency without the onset of combustion knock. Recent injector 
design advances, improved electronic engine management systems and the 
introduction of multiple injection events per cylinder firing cycle 
promote better mixing of the air and fuel, enhance combustion rates, 
increase residual exhaust gas tolerance and improve cold start 
emissions. SGDI engines achieve higher power density and match well 
with other technologies, such as boosting and variable valvetrain 
designs. The light-duty 2012-2016 MY vehicle rule estimated the 
effectiveness

[[Page 57232]]

of SGDI to be between 2 and 3 percent. NHTSA and EPA revised these 
estimated accounting for the use and testing methods for these vehicles 
along with confidential business information estimates received from 
manufacturers while developing the program. Based on these revisions, 
NHTSA and EPA estimate the range of 1 to 2 percent for SGDI.
(c) Diesel Engine Technologies
    Different types of diesel engines are used in vocational vehicles, 
depending on the application. They fall into the categories of Light, 
Medium, and Heavy Heavy-duty Diesel engines. The Light Heavy-duty 
Diesel engines typically range between 4.7 and 6.7 liters displacement. 
The Medium Heavy-duty Diesel engines typically have some overlap in 
displacement with the Light Heavy-duty Diesel engines and range between 
6.7 and 9.3 liters. The Heavy Heavy-duty Diesel engines typically are 
represented by engines between 10.8 and 16 liters.
    Baseline Engine: There are three baseline diesel engines, a Light, 
Medium, and a Heavy Heavy-duty Diesel engine. The agencies developed 
the baseline diesel engine as a 2010 model year engine with an 
aftertreatment system which meets EPA's 0.2 grams of NOX/
bhp-hr standard with an SCR system along with EGR and meets the PM 
emissions standard with a diesel particulate filter with active 
regeneration. The engine is turbocharged with a variable geometry 
turbocharger. As noted above in Section III.A.1.b, the agencies 
received comments from Navistar stating that the agencies used an 
artificially low baseline CO2 emissions level which was 
tilted toward the use of SCR aftertreatment system. As discussed in 
Section III.A.1.b, the agencies disagree with the statement that SCR is 
infeasible. Additional responses from the agencies are available in the 
Response to Comments document, Section 6.2.\279\ The following 
discussion of technologies describes improvements over the 2010 model 
year baseline engine performance, unless otherwise noted. Further 
discussion of the baseline engine and its performance can be found in 
Section III.C.2.(c)(i) below. The following discussion of effectiveness 
is generally in comparison to 2010 baseline engine performance, and is 
in reference to performance in terms of the Heavy-duty FTP that would 
be used for compliance for these engine standards. This is in 
comparison to the steady state SET procedure that would be used for 
compliance purposes for the engines used in Class 7 and 8 tractors. See 
Section II.B.2.(i) above.
---------------------------------------------------------------------------

    \279\ U.S. EPA. Greenhouse Gas Emissions Standards and Fuel 
Efficiency Standards for Medium- and Heavy-Duty Engines and 
Vehicles--EPA Response to Comments Document for Joint Rulemaking. 
EPA-420-R-11-004. Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    Turbochargers: Improved efficiency of a turbocharger compressor or 
turbine could reduce fuel consumption by approximately 1 to 2 percent 
over today's variable geometry turbochargers in the market today. The 
2010 NAS report identified technologies such as higher pressure ratio 
radial compressors, axial compressors, and dual stage turbochargers as 
design paths to improve turbocharger efficiency.
    Low Temperature Exhaust Gas Recirculation: Most LHDD, MHDD, and 
HHDD engines sold in the U.S. market today use cooled EGR, in which 
part of the exhaust gas is routed through a cooler (rejecting energy to 
the engine coolant) before being returned to the engine intake 
manifold. EGR is a technology employed to reduce peak combustion 
temperatures and thus NOX. Low-temperature EGR uses a larger 
or secondary EGR cooler to achieve lower intake charge temperatures, 
which tend to further reduce NOX formation. If the 
NOX requirement is unchanged, low-temperature EGR can allow 
changes such as more advanced injection timing that will increase 
engine efficiency slightly more than one percent. Because low-
temperature EGR reduces the engine's exhaust temperature, it may not be 
compatible with exhaust energy recovery systems such as 
turbocompounding or a bottoming cycle.
    Engine Friction Reduction: Reduced friction in bearings, valve 
trains, and the piston-to-liner interface will improve efficiency. Any 
friction reduction must be carefully developed to avoid issues with 
durability or performance capability. Estimates of fuel consumption 
improvements due to reduced friction range from 0.5 to 1.5 
percent.\280\
---------------------------------------------------------------------------

    \280\ See TIAX, Note 198, pg. 4-15.
---------------------------------------------------------------------------

    Selective catalytic reduction: This technology is common on 2010 
heavy-duty diesel engines. Because SCR is a highly effective 
NOX aftertreatment approach, it enables engines to be 
optimized to maximize fuel efficiency, rather than minimize engine-out 
NOX. 2010 SCR systems are estimated to result in improved 
engine efficiency of approximately 4 to 5 percent compared to a 2007 
in-cylinder EGR-based emissions system and by an even greater 
percentage compared to 2010 in-cylinder approaches.\281\ As more 
effective low-temperature catalysts are developed, the NOX 
conversion efficiency of the SCR system will increase. Next-generation 
SCR systems could then enable still further efficiency improvements; 
alternatively, these advances could be used to maintain efficiency 
while down-sizing the aftertreatment. We estimate that continued 
optimization of the catalyst could offer 1 to 2 percent reduction in 
fuel use over 2010 model year systems in the 2014 model year.\282\ The 
agencies also estimate that continued refinement and optimization of 
the SCR systems could provide an additional 2 percent reduction in the 
2017 model year.
---------------------------------------------------------------------------

    \281\ Stanton, D. ``Advanced Diesel Engine Technology 
Development for High Efficiency, Clean Combustion.'' Cummins, Inc. 
Annual Progress Report 2008 Vehicle Technologies Program: Advanced 
Combustion Engine Technologies, U.S. Department of Energy. Pp 113-
116. December 2008.
    \282\ See TIAX, Note 198, pg. 4-9
---------------------------------------------------------------------------

    Improved Combustion Process: Fuel consumption reductions in the 
range of 1 to 4 percent are identified in the 2010 NAS report through 
improved combustion chamber design, higher fuel injection pressure, 
improved injection shaping and timing, and higher peak cylinder 
pressures.\283\
---------------------------------------------------------------------------

    \283\ See 2010 NAS Report, Note 197, page 56.
---------------------------------------------------------------------------

    Reduced Parasitic Loads: Accessories that are traditionally gear or 
belt driven by a vehicle's engine can be optimized and/or converted to 
electric power. Examples include the engine water pump, oil pump, fuel 
injection pump, air compressor, power-steering pump, cooling fans, and 
the vehicle's air-conditioning system. Optimization and improved 
pressure regulation may significantly reduce the parasitic load of the 
water, air and fuel pumps. Electrification may result in a reduction in 
power demand, because electrically powered accessories (such as the air 
compressor or power steering) operate only when needed if they are 
electrically powered, but they impose a parasitic demand all the time 
if they are engine driven. In other cases, such as cooling fans or an 
engine's water pump, electric power allows the accessory to run at 
speeds independent of engine speed, which can reduce power consumption. 
The TIAX study used 2 to 4 percent fuel consumption improvement for 
accessory electrification, with the understanding that electrification 
of accessories will have more effect in short-haul/urban applications 
and less benefit in line-haul applications.\284\
---------------------------------------------------------------------------

    \284\ See TIAX. Note 198, Pages 3-5.

---------------------------------------------------------------------------

[[Page 57233]]

(2) What is the projected technology package's effectiveness and cost?
(a) Vocational Vehicles
(i) Baseline Vocational Vehicle Performance
    The baseline vocational vehicle model is defined in the GEM, as 
described in RIA Chapter 4.4.6. At proposal, the agencies used a 
baseline rolling resistance coefficient for today's vocational vehicle 
fleet of 9.0 kg/metric ton.\285\ As discussed in Section II.D.1, the 
agencies conducted a tire rolling resistance evaluation of tires used 
in vocational vehicles. The agencies found that the average rolling 
resistance of the tires was lower than the agencies' assessment at 
proposal. Based on this new information and our understanding of the 
potential to improve tire rolling resistance by 2014, the agencies are 
setting the vocational truck standard premised on the use of tires with 
a rolling resistance coefficient of 7.7 kg/metric ton. This value is 
consistent with the average performance of the subset of tires the 
agencies tested. We are projecting this standard will drive a 5 percent 
reduction in tire rolling resistance on average across the fleet. We 
are projecting this 5 percent reduction based on our expectation that 
manufacturers will desire to bring all of their tires below the 
standard (not just comply on average) and knowing manufacturers will 
need some degree of overcompliance to ensure despite manufacturing 
variability and test to test variability their products are compliant 
with the emission standards. In order to reflect both this tighter 
standard (based on 7.7) and the 5 percent reduction in rolling 
resistance we project it will accomplish, we are modeling the baseline 
performance of vocational truck tires as 8.1 kg/metric ton.
---------------------------------------------------------------------------

    \285\ The baseline tire rolling resistance for this segment of 
vehicles was derived for the proposal based on the current baseline 
tractor and passenger car tires. The baseline tractor drive tire has 
a rolling resistance of 8.2 kg/metric ton based on SmartWay testing. 
The average passenger car has a tire rolling resistance of 9.75 kg/
metric ton based on a presentation made to CARB by the Rubber 
Manufacturer's Association. As noted above, further analysis has 
resulted in an estimate of improved performance in the baseline 
fleet, which is based entirely on use of LRR tires on vocational 
vehicles (not cars). Additional details are available in the RIA 
chapter 2.
---------------------------------------------------------------------------

    Further vehicle technology is not included in this baseline, as 
discussed below in the discussion of the baseline vocational vehicle. 
The baseline engine fuel consumption represents a 2010 model year 
diesel engine, as described in RIA Chapter 4. Using these values, the 
baseline performance of these vehicles is included in Table III-12.
    The agencies note that the baseline performance derived for the 
final rule slightly differs from the values derived for the NPRM. The 
first difference is due to the change in rolling resistance from 9.0 to 
8.1 kg/metric ton based on the agencies' post-proposal test results. 
Second, there are minor differences in the fuel consumption and 
CO2 emissions due to the small modifications made to the 
GEM, as noted in RIA Chapter 4. In addition, the HHD vocational vehicle 
baseline performance for the final rule uses a revised payload 
assumption from 38,000 to 15,000 pounds, as described in Section 
II.D.3.c.iii.

          Table III-12--Baseline Vocational Vehicle Performance
------------------------------------------------------------------------
                                           Vocational vehicle
------------------------------------------------------------------------
                                              Medium heavy- Heavy  heavy-
                                 Heavy-duty       duty          duty
------------------------------------------------------------------------
Fuel Consumption Baseline               40.0          24.3          23.2
 (gallon/1,000 ton-mile)......
CO2 Baseline (grams CO2/ton-           408           247           236
 mile)........................
------------------------------------------------------------------------

(ii) Vocational Vehicle Technology Package
    The final program for vocational vehicles for this phase of 
regulatory standards is based on the performance of tire and engine 
technologies. Aerodynamics technology, weight reduction, drive train 
improvement, and hybrid power trains are not included for the reasons 
discussed above in Section III.C (1) and Section II.D.
    The assessment of the final technology effectiveness was developed 
through the use of the GEM. To account for the two final engine 
standards, EPA is finalizing the use of a 2014 model year fuel 
consumption map in the GEM to derive the 2014 model year truck standard 
and a 2017 model year fuel consumption map to derive the 2017 model 
year truck standard. (These fuel consumption maps reflect the main 
standards for HD diesel engines, not the alternative engine standards.) 
The agencies estimate that the rolling resistance of 50 percent of the 
tires can be reduced by 10 percent in the 2014 model year, for an 
overall reduction in rolling resistance of 5 percent. The vocational 
vehicle standards for all three regulatory categories were determined 
using a tire rolling resistance coefficient of 7.7 kg/metric ton in the 
2014 model year. The set of input parameters which are modeled in GEM 
are shown in Table III-13.

                         Table III-13--GEM Inputs for Final Vocational Vehicle Standards
----------------------------------------------------------------------------------------------------------------
                                                                       2014 MY                   2017 MY
----------------------------------------------------------------------------------------------------------------
Engine......................................................   2014 MY 7L for LHD/MHD    2017 MY 7L for LHD/MHD
                                                               and 15L for HHD Trucks   and 15L for HHD Trucks.
Tire Rolling Resistance (kg/metric ton).....................                      7.7                       7.7
----------------------------------------------------------------------------------------------------------------

    The agencies developed the final standards by using the engine and 
tire rolling resistance inputs in the GEM, as shown in Table III-13. 
The percent reductions shown in Table III-14 reflect improvements over 
the 2010 model year baseline vehicle with a 2010 model year baseline 
engine.

[[Page 57234]]

                     Table III-14--Final Vocational Vehicle Standards and Percent Reductions
----------------------------------------------------------------------------------------------------------------
                                                                                Vocational vehicle
                                                                 -----------------------------------------------
                                                                   Light heavy-    Medium heavy-   Heavy heavy-
                                                                       duty            duty            duty
----------------------------------------------------------------------------------------------------------------
2016 MY Fuel Consumption Standard (gallon/1,000 ton-mile).......            38.1            23.0            22.2
2017 MY Fuel Consumption Standard (gallon/1,000 ton-mile).......            36.7            22.1            21.8
2014 MY CO2 Standard (grams CO2/ton-mile).......................             388             234             226
2017 MY CO2 Standard (grams CO2/ton-mile).......................             373             225             222
Percent Reduction from 2010 baseline in 2014 MY.................              5%              5%              4%
Percent Reduction from 2010 baseline in 2017 MY.................              8%              9%              6%
----------------------------------------------------------------------------------------------------------------

(iii) Technology Package Cost
    The agencies did not receive any substantial comments on the engine 
costs proposed. Thus the agencies are projecting the costs of the 
technologies used to develop the final standards based on the costs 
used in the proposal, but revised to reflect 2009$, new ICMs, and a 50 
percent penetration rate of low rolling resistance tires (as explained 
above). EPA and NHTSA developed the costs of LRR tires based on the ICF 
report. The estimated cost per truck is $81 (2009$) for LHD and MHD 
trucks and $97 (2009$) for HHD trucks. These costs include a low 
complexity ICM of 1.18 and are applicable in the 2014 model year.
(iv) Reasonableness of the Final Vocational Vehicle Standards
    The final standards would not only add only a small amount to the 
vehicle cost, but are highly cost effective, an estimated $20 ton of 
CO2eq per vehicle in 2030.\286\ This is even less than the 
estimated cost effectiveness for CO2eq removal under the 
light-duty vehicle rule, already considered by the agencies to be a 
highly cost effective reduction.\287\ Moreover, the modest cost of 
controls is recovered almost immediately due to the associated fuel 
savings, as shown in the payback analysis included in Table VIII-7. 
Given that the standards are technically feasible within the lead time 
afforded by the 2014 model year, are inexpensive and highly cost 
effective, and do not have other adverse potential impacts (e.g., there 
are no projected negative impacts on safety or vehicle utility), the 
final standards represent a reasonable choice under section 202(a) of 
the CAA and NHTSA's EISA authority under 49 U.S.C. 32902(k)(2), and the 
agencies believe that the standards are consistent with their 
respective authorities. Based on the discussion above, NHTSA believes 
these standards are the maximum feasible under EISA.
---------------------------------------------------------------------------

    \286\ See Section VIII.D.
    \287\ As noted above, the light-duty rule had an estimated cost 
per ton of $50 when considering the vehicle program costs only and a 
cost of -$210 per ton considering the vehicle program costs along 
with fuel savings in 2030. See 75 FR 25515, Table III.H.3-1.
---------------------------------------------------------------------------

(v) Alternative Vehicle Standards Considered
    The agencies are not finalizing vehicle standards less stringent 
than the final standards because the agencies believe these standards 
are highly cost effective, as just explained.
    The agencies considered finalizing truck standards which are more 
stringent reflecting the inclusion of hybrid powertrains in those 
vocational vehicles where use of hybrid powertrains is appropriate. The 
agencies estimate that a 25 percent utilization rate of hybrid 
powertrains in MY 2017 vocational vehicles would add, on average, 
$30,000 to the cost of each vehicle and more than double the cost of 
the rule for this sector. See the RIA at chapter 6.1.8. The emission 
reductions associated with these very high costs appear to be modest. 
See the RIA Table 6-14. In addition, the agencies are finalizing 
flexibilities in the form of generally applicable credit opportunities 
for advanced technologies, to encourage use of hybrid powertrains. See 
Section IV.C. 2 below. Several commenters recommended that in addition 
to hybrid powertrains, the agencies consider setting more stringent 
standards based on the use of aerodynamic improvements, weight 
reduction, idle shutdown technologies, vehicle speed limiters, and 
specific transmission technologies. As described above, we are not 
finalizing standards based on these technologies for reasons that 
related to the unique nature of the very diverse vocational vehicle 
segment. At this time, the agencies have no means to determine the 
current baseline aerodynamic performance of all vocational vehicles 
(ranging from concrete mixers to school buses), nor a means to project 
to what degree the aerodynamic performance could be improved without 
compromising the utility of the vehicle. Absent this information, the 
agencies cannot set a standard based on improvements in aerodynamic 
performance. The agencies face similar obstacles regarding our ability 
to project the utility tradeoffs that may exist between limitations on 
vehicle speed or reductions in vehicle mass and utility and safety of 
vocational vehicles. We are confident the answer to those questions 
will differ for a school bus compared to a concrete mixer compared to a 
fire truck compared to an ambulance. Absent an approach to set distinct 
standards for each of the vocational vehicle types and the information 
necessary to determine the appropriate level of performance for those 
vehicles, the agencies cannot set standards for vocational vehicles 
based on the use of these technologies. For these reasons, the agencies 
are not adopting more comprehensive standards for vocational vehicles. 
The agencies do agree that at least some vocational vehicles can be 
made more efficient through the use of technologies, including those 
technologies mentioned in the comments, and the agencies fully intend 
to take on the challenge of developing the data, test procedures and 
regulatory structures necessary to set more comprehensive standards for 
vocational trucks in the future.
(b) Gasoline Engines
(i) Baseline Gasoline Engine Performance
    EPA and NHTSA developed the reference heavy-duty gasoline engines 
to represent a 2010 model year engine compliant with the 0.20 g/bhp-hr 
NOX standard for on-highway heavy-duty engines.
    NHTSA and EPA developed the baseline fuel consumption and 
CO2 emissions for the gasoline engines from manufacturer 
reported CO2 values used in the certification of non-GHG 
pollutants. The baseline engine for the analysis was developed to 
represent a 2011 model year engine, because this is the most current 
information available. The average CO2 performance of the 
heavy-duty gasoline engines was 660 g/bhp-hour, which will be used as a

[[Page 57235]]

baseline. The baseline gasoline engines are all stoichiometric port 
fuel injected V-8 engines without cam phasers or other variable valve 
timing technologies. While they may reflect some degree of static valve 
timing optimization for fuel efficiency they do not reflect the 
potential to adjust timing with engine speed.
(ii) Gasoline Engine Technology Package Effectiveness
    The gasoline engine technology package includes engine friction 
reduction, coupled cam phasing, and SGDI to produce an overall five 
percent reduction from the reference engine based on the Heavy-duty 
Lumped Parameter model. The agencies are projecting a 100 percent 
application rate of this technology package to the heavy-duty gasoline 
engines, which results in a CO2 standard of 627 g/bhp-hr and 
a fuel consumption standard of 7.05 gallon/100 bhp-hr. As discussed in 
Section II.D.b.ii, the agencies are adopting gasoline engine standards 
that begin in the 2016 model year based on the agencies' projection of 
the engine redesign schedules for the small number of engines in this 
category.
(iii) Gasoline Engine Technology Package Cost
    For the proposed costs, the agencies considered both the direct or 
``piece'' costs and indirect costs of individual components of 
technologies. For the direct costs, the agencies followed a BOM 
approach employed by NHTSA and EPA in the light-duty 2012-2016 MY 
vehicle rule. In this final action, the agencies are using marked up 
gasoline engine technology costs developed for the HD Pickup Truck and 
Van segment because these engines are made by the same manufacturers 
(primarily by Ford and GM) and are simply, sold as loose engines rather 
than as complete vehicles. Hence the engine cost estimates are 
fundamentally the same. The agencies did not receive any comments 
recommending adjustments to the proposed gasoline engine technology 
costs. The costs summarized in Table III-15 are consistent with the 
proposed values, but updated to reflect 2009$ and new ICMs. The costs 
shown in Table III-15 include a low complexity ICM of 1.24 and are 
applicable in the 2016 model year. No learning effects are applied to 
engine friction reduction costs, while flat-portion of the curve 
learning is considered applicable to both coupled cam phasing and SGDI.

 Table III-15--Heavy-Duty Gasoline Engine Technology Costs Inclusive of
                          Indirect Cost Markups
                                 [2009$]
------------------------------------------------------------------------
                                                                2016 MY
------------------------------------------------------------------------
Engine Friction Reduction....................................        $95
Coupled Cam Phasing..........................................         46
Stoichiometric Gas Direct Injection..........................        452
                                                              ----------
    Total....................................................        594
------------------------------------------------------------------------

(iv) Reasonableness of the Final Standard
    The final engine standards are reasonable and consistent with the 
agencies' respective authorities. With respect to the 2016 MY standard, 
all of the technologies on which the standards are predicated have been 
demonstrated and their effectiveness is well documented. The final 
standards reflect a 100 percent application rate for these 
technologies. The costs of adding these technologies remain modest 
across the various engine classes as shown in Table 0-15. Use of these 
technologies would add only a small amount to the cost of the 
vehicle,\288\ and the associated reductions are highly cost effective, 
an estimated $20 per ton of CO2eq per vehicle.\289\ This is 
even more cost effective than the estimated cost effectiveness for 
CO2eq removal and fuel economy improvement under the light-
duty vehicle rule, already considered by the agencies to be a highly 
cost effective reduction.\290\ Accordingly, EPA and NHTSA view these 
standards as reflecting an appropriate balance of the various statutory 
factors under section 202(a) of the CAA and under NHTSA's EISA 
authority at 49 U.S.C. 32902(k)(2). Based on the discussion above, 
NHTSA believes these standards are the maximum feasible under EISA.
---------------------------------------------------------------------------

    \288\ Sample 2010 MY vocational vehicles range in price between 
$40,000 for a Class 4 work truck to approximately $200,000 for a 
Class 8 refuse hauler. See pages 16-17 of ICF's ``Investigation of 
Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy-
Duty On-Road Vehicles.'' July 2010.
    \289\ See Vocational Vehicle CO2 savings and 
technology costs in Table 7-4 in RIA chapter 7.
    \290\ The light-duty rule had an estimated cost per ton of $50 
when considering the vehicle program costs only and a cost of -$210 
per ton considering the vehicle program costs along with fuel 
savings in 2030. See 75 FR 25515, Table III.H.3-1.
---------------------------------------------------------------------------

    Several commenters suggested that the lead time provided by the 
agencies for heavy-duty pickups and vans and by extension the 2016 
gasoline engine standards were unnecessarily long. The agencies do not 
agree with this assessment. The technologies that we are considering 
here cannot simply be bolted on to an existing engine but can only be 
effectively applied through an integrated design and development 
process. The four years lead time provided here is short in the context 
of engine redesigns and is only possible in part because the standards 
align with engine manufacturers' planned redesign processes that are 
either just starting or will be starting within the year. These 
standards set a clear metric of performance for those planned redesigns 
and we project will lead manufacturers to include a number of 
technologies that would not otherwise have been incorporated into those 
engines.
(v) Alternative Gasoline Engine Standards Considered
    The agencies are not finalizing gasoline standards less stringent 
than the final standards because the agencies believe these standards 
are feasible in the lead time provided, inexpensive, and highly cost 
effective.
    The final rule reflects 100 percent penetration of the technology 
package on whose performance the standard is based, so some additional 
technology would need to be added to obtain further improvements. The 
agencies considered finalizing gasoline engine standards which are more 
stringent reflecting the inclusion of cylinder deactivation and other 
advanced technologies. However, the agencies are not finalizing this 
level of stringency because our assessment is that these technologies 
cannot be adapted to the higher average engine loads of heavy-duty 
vehicles for production by the 2017 model year. We intend to continue 
to evaluate the potential for further gasoline engine improvements 
building on the work done for light-duty passenger cars and trucks as 
we begin work on the next phase of heavy-duty regulations.
(c) Diesel Engines
(i) Baseline Diesel Engine Performance
    EPA and NHTSA developed the baseline heavy-duty diesel engines to 
represent a 2010 model year engine compliant with the 0.20 g/bhp-hr 
NOX standard for on-highway heavy-duty engines.
    The agencies utilized 2007 through 2011 model year CO2 
certification levels from the Heavy-duty FTP cycle as the basis for the 
baseline engine CO2 performance. The pre-2010 data are 
subsequently adjusted to represent 2010 model year engine maps by using 
predefined technologies including SCR and other systems that are being 
used in current 2010 production. The engine CO2 results were 
then sales weighted

[[Page 57236]]

within each regulatory subcategory to develop an industry average 2010 
model year reference engine, as shown in Table III-16. The level of 
CO2 emissions and fuel consumption of these engines varies 
significantly, where the engine with the highest CO2 
emissions is estimated to be 20 percent greater than the sales weighted 
average. Details of this analysis are included in RIA Chapter 2.

 Table III-16--2010 Model Year Reference Diesel Engine Performance Over
                        the Heavy-Duty FTP Cycle
------------------------------------------------------------------------
                               CO2 emissions  (g/     Fuel consumption
                                     bhp-hr)         (gallon/100 bhp-hr)
------------------------------------------------------------------------
LHD Diesel..................                   630                  6.19
MHD Diesel..................                   630                  6.19
HHD Diesel..................                   584                  5.74
------------------------------------------------------------------------

(ii) Diesel Engine Packages
    The diesel engine technology packages for the 2014 model year 
include engine friction reduction, improved aftertreatment 
effectiveness, improved combustion processes, and low temperature EGR 
system optimization. The improvements in parasitic and friction losses 
come through piston designs to reduce friction, improved lubrication, 
and improved water pump and oil pump designs to reduce parasitic 
losses. The aftertreatment improvements are available through lower 
backpressure of the systems and optimization of the engine-out 
NOX levels. Improvements to the EGR system and air flow 
through the intake and exhaust systems, along with turbochargers can 
also produce engine efficiency improvements. It should be pointed out 
that individual technology improvements are not additive to each other 
due to the interaction of technologies. The agencies assessed the 
impact of each technology over the Heavy-duty FTP and project an 
overall cycle improvement in the 2014 model year of 3 percent for HHD 
diesel engines and 5 percent for LHD and MHD diesel engines, as 
detailed in RIA Chapter 2.4.2.9 and 2.4.2.10. EPA used a 100 percent 
application rate of this technology package to determine the level of 
the final 2014 MY standards
    Recently, EPA's heavy-duty highway engine program for criteria 
pollutants provided new emissions standards for the industry in three 
year increments. The heavy-duty engine manufacturer product plans have 
fallen into three year cycles to reflect this environment. EPA is 
finalizing CO2 emission standards recognizing the 
opportunity for technology improvements over this time frame while 
reflecting the typical heavy-duty engine manufacturer product plan 
redesign cycles. Thus, the agencies are establishing initial standards 
for the 2014 model year and a more stringent standard for these heavy-
duty engines beginning in the 2017 model year.
    The 2017 model year technology package for LHD and MHD diesel 
engine includes continued development and refinement of the 2014 model 
year technology package, in particular the additional improvement to 
aftertreatment systems. This package leads to a projected 9 percent 
reduction for LHD and MHD diesel engines in the 2017 model year. The 
HHD diesel engine technology packages for the 2017 model year include 
the continued development of the 2014 model year technology package. A 
similar approach to evaluating the impact of individual technologies as 
taken to develop the overall reduction of the 2014 model year package 
was taken with the 2017 model year package. The Heavy-duty FTP cycle 
improvements lead to a 5 percent reduction on the cycle for HHDD, as 
detailed in RIA Chapter 2.4.2.13. The agencies used a 100 percent 
application rate of the technology package to determine the final 2017 
MY standards. The agencies believe that bottom cycling technologies are 
still in the development phase and will not be ready for production by 
the 2017 model year.\291\ Therefore, these technologies were not 
included in determining the stringency of the final standards. However, 
we do believe the bottoming cycle approach represents a significant 
opportunity to reduce fuel consumption and GHG emissions in the future 
for vehicles that operate under primarily steady-state conditions like 
line-haul tractors and some vocational vehicles. As discussed above, we 
also considered setting standards based on the use of hybrid 
powertrains that are a better match to many vocational vehicle duty 
cycles but have decided for the reasons articulated above to not base 
the vocational vehicle standard on the use of hybrid technologies in 
this first regulation. However, EPA and NHTSA are both finalizing 
provisions described in Section IV to create incentives for 
manufacturers to continue to invest to develop these technologies in 
the believe that with further development these technologies can form 
the basis of future standards.
---------------------------------------------------------------------------

    \291\ TIAX noted in their report to the NAS panel that the 
engine improvements beyond 2015 model year included in their report 
are highly uncertain, though they include waste heat recovery in the 
engine package for 2016 through 2020 (page 4-29).
---------------------------------------------------------------------------

    The overall projected improvements in CO2 emissions and 
fuel consumption over the baseline are included in Table III-17.

 Table III-17--Percent Fuel Consumption and CO2 Emission Reductions Over
                        the Heavy-duty FTP Cycle
------------------------------------------------------------------------
                                                          2014     2017
------------------------------------------------------------------------
LHD Diesel............................................       5%       9%
MHD Diesel............................................        5        9
HHD Diesel............................................        3        5
------------------------------------------------------------------------

(iii) Technology Package Costs
    NHTSA and EPA jointly developed costs associated with the engine 
technologies to assess an overall package cost for each regulatory 
category. Our engine cost estimates for diesel engines used in 
vocational vehicles include a separate analysis of the incremental part 
costs, research and development activities, and additional equipment, 
such as emissions equipment to measure N2O emissions. Our 
general approach used elsewhere in this action (for HD pickup trucks, 
gasoline engines, Class 7 and 8 tractors, and Class 2b-8 vocational 
vehicles) estimates a direct manufacturing cost for a part and marks it 
up based on a factor to account for indirect costs. See also 75 FR 
25376. We believe that approach is appropriate when compliance with 
final standards is achieved generally by installing new parts and 
systems purchased from a supplier. In such a case, the supplier is 
conducting the bulk of the research and development on the new parts 
and systems and including those costs in the purchase price paid by the 
original equipment manufacturer. The indirect costs incurred by the 
original equipment manufacturer need not include much cost to cover 
research and development since the bulk of that effort is already done. 
For the MHD and

[[Page 57237]]

HHD diesel engine segment, however, the agencies believe we can make a 
more accurate estimate of technology cost using this alternate approach 
because the primary cost is not expected to be the purchase of parts or 
systems from suppliers or even the production of the parts and systems, 
but rather the development of the new technology by the original 
equipment manufacturer itself. Therefore, the agencies believe it more 
accurate to directly estimate the indirect costs. EPA commonly uses 
this approach in cases where significant investments in research and 
development can lead to an emission control approach that requires no 
new hardware. For example, combustion optimization may significantly 
reduce emissions and cost a manufacturer millions of dollars to develop 
but will lead to an engine that is no more expensive to produce. Using 
a bill of materials approach would suggest that the cost of the 
emissions control was zero reflecting no new hardware and ignoring the 
millions of dollars spent to develop the improved combustion system. 
Details of the cost analysis are included in the RIA Chapter 2. To 
reiterate, we have used this different approach because the MHD and HHD 
diesel engines are expected to comply in large part via technology 
changes that are not reflected in new hardware but rather knowledge 
gained through laboratory and real world testing that allows for 
improvements in control system calibrations--changes that are more 
difficult to reflect through direct costs with indirect cost 
multipliers.
    The agencies developed the engineering costs for the research and 
development of diesel engines with lower fuel consumption and 
CO2 emissions. The aggregate costs for engineering hours, 
technician support, dynamometer cell time, and fabrication of prototype 
parts are estimated at $6.8 million (2009$) per manufacturer per year 
over the five years covering 2012 through 2016. In aggregate, this 
averages out to $284 per engine during 2012 through 2016 using an 
annual sales value of 600,000 light, medium, and heavy heavy-duty 
engines. The agencies received comments from Horriba regarding the 
assumption the agencies used in the proposal that said manufacturers 
would need to purchase new equipment for measuring N2O and 
the associated costs. Horriba provided information regarding the cost 
of stand-alone FTIR instrumentation (estimated at $50,000 per unit) and 
cost of upgrading existing emission measurement systems with NDIR 
analyzers (estimated at $25,000 per unit). The agencies further 
analyzed our assumptions along with Horriba's comments. Thus, we have 
revised the equipment costs estimates and assumed that 75 percent of 
manufacturers would update existing equipment while the other 25 
percent would require new equipment. The agencies are estimating costs 
of $63,087 (2009$) per engine manufacturer per engine subcategory 
(light, medium, and heavy HD) to cover the cost of purchasing photo-
acoustic measurement equipment for two engine test cells. This would be 
a one-time cost incurred in the year prior to implementation of the 
standard (i.e., the cost would be incurred in 2013). In aggregate, this 
averages out to less than $1 per engine in 2013 using an annual sales 
value of 600,000 light, medium, and heavy HD engines.
    EPA also developed the incremental piece cost for the components to 
meet each the 2014 and 2017 standards. These costs shown in Table III-
18 which include a low complexity ICM of 1.15; flat-portion of the 
curve learning is considered applicable to each technology.

   Table III-18--Heavy-Duty Diesel Engine Component Costs Inclusive of
                         Indirect Cost Markups a
                                 [2009$]
------------------------------------------------------------------------
                                    2014 Model year     2017 Model year
------------------------------------------------------------------------
Cylinder Head (flow optimized,    $6 (MHD & HH), $11  $6 (MHD & HHD),
 increased firing pressure,        (LHD).              $10 (LHD).
 improved thermal management).
Exhaust Manifold (flow            $0................  $0.
 optimized, improved thermal
 management).
Turbocharger (improved            $18...............  $17.
 efficiency).
EGR Cooler (improved efficiency)  $4................  $3.
Water Pump (optimized, variable   $91...............  $84.
 vane, variable speed).
Oil Pump (optimized)............  $5................  $4.
Fuel Pump (higher working         $5................  $4.
 pressure, increased efficiency,
 improved pressure regulation).
Fuel Rail (higher working         $10 (MHD & HHD),    $9 (MHD & HHD),
 pressure).                        $12 (LHD).          $11 (LHD).
Fuel Injector (optimized,         $11 (MHD & HHD),    $10 (MHD & HHD),
 improved multiple event           $15 (LHD).          $13 (LHD).
 control, higher working
 pressure).
Piston (reduced friction skirt,   $3................  $3.
 ring and pin).
Aftertreatment system (improved   $0 (MHD & HHD),     $0 (MHD & HHD),
 effectiveness SCR, dosing,        $111 (LHD).         $101 (LHD).
 dpf)a.
Valve Train (reduced friction,    $82 (MHD), $109     $76 (MHD), $101
 roller tappet).                   (LHD).              (LHD).
------------------------------------------------------------------------
Note:
a Note that costs for aftertreatment improvements for MHD and HHD diesel
  engines are covered via the engineering costs (see text). For LH
  diesel engines, we have included the cost of aftertreatment
  improvements as a technology cost.

    The overall costs for each diesel engine regulatory subcategory are 
included in Table III-19.

         Table III-19--Diesel Engine Technology Costs per Engine
                                 [2009$]
------------------------------------------------------------------------
                                                          2014     2017
------------------------------------------------------------------------
LHD Diesel............................................     $388     $358
MHD Diesel............................................      234      216
HHD Diesel............................................      234      216
------------------------------------------------------------------------

Reasonableness of the Final Standards
    The final engine standards appear to be reasonable and consistent 
with the agencies' respective authorities. With respect to the 2014 and 
2017 MY standards, all of the technologies on which the standards are 
based have already been demonstrated and their effectiveness is well 
documented. The final standards reflect a 100 percent application rate 
for these technologies.

[[Page 57238]]

The costs of adding these technologies remain modest across the various 
engine classes as shown in Table III-19. Use of these technologies 
would add only a small amount to the cost of the vehicle,\292\ and the 
associated reductions are highly cost effective, an estimated $20 per 
ton of CO2eq per vehicle.\293\ This is even more cost 
effective than the estimated cost effectiveness for CO2eq 
removal and fuel economy improvement under the light-duty vehicle rule, 
already considered by the agencies to be a highly cost effective 
reduction.\294\ Accordingly, EPA and NHTSA view these standards as 
reflecting an appropriate balance of the various statutory factors 
under section 202(a) of the CAA and under NHTSA's EISA authority at 49 
U.S.C. 32902(k)(2). Based on the discussion above, NHTSA believes these 
standards are the maximum feasible under EISA.
---------------------------------------------------------------------------

    \292\ Sample 2010 MY vocational vehicles range in price between 
$40,000 for a Class 4 work truck to approximately $200,000 for a 
Class 8 refuse hauler. See pages 16-17 of ICF's ``Investigation of 
Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy-
Duty On-Road Vehicles.'' July 2010.
    \293\ See RIA chapter 7, Table 7-4.
    \294\ The light-duty rule had a cost per ton of $50 when 
considering the vehicle program costs only and a cost of -$210 per 
ton considering the vehicle program costs along with fuel savings in 
2030. See 75 FR 25515, Table III.H.3-1.
---------------------------------------------------------------------------

(v) Alternative Diesel Engine Standards Considered
    Other than the specific option related to legacy engine products, 
the agencies are not finalizing diesel engine standards less stringent 
than the final standards because the agencies believe these standards 
are highly cost effective.
    The agencies have not considered finalizing diesel engine standards 
which are more stringent because we have exhausted the list of engine 
technologies that we believe are directly applicable to medium- and 
heavy-duty diesel engines used in vocational applications. We are 
continuing to evaluate the potential for bottoming cycle technologies 
to be used in the future, however it is not clear today that this 
technology, although promising for more steady-state operation will 
provide any significant efficiency improvement under the more transient 
operating cycles typical of vocational vehicles. Moreover, as stated at 
II.D above, the agencies do not believe that this technology will be 
available in the time frame of this rule in any case.

IV. Final Regulatory Flexibility Provisions

    This section describes flexibility provisions intended to advance 
the goals of the overall program while providing alternate pathways to 
achieve those goals, consistent with the agencies' statutory authority, 
as well as with Executive Order 13563.\295\ The primary flexibility 
provisions for combination tractors and vocational vehicles and the 
engines installed in these vehicles are incorporated in a program of 
averaging, banking, and trading of credits. For HD pickups and vans, 
the primary flexibility provision is also an ABT program expressed in 
the fleet average form of the standards, along with provisions for 
credit and deficit carry-forward and for trading, patterned after the 
agencies' light-duty vehicle GHG and CAFE programs. Furthermore, EPA 
will allow manufacturers to comply with the N2O and 
CH4 standards using CO2 credits and is providing 
an opportunity for engine manufacturers to earn N2O credits 
that can be used to comply with the CO2 standards. However, 
EPA is not adopting an emission credit program associated with the 
CH4 or HFC standards. This section also describes other 
flexibility provisions that apply, including advanced technology 
credits, innovative technology credits and early compliance credits.
---------------------------------------------------------------------------

    \295\ Section 4 of EO 13563 states that ``Where relevant, 
feasible, and consistent with regulatory objectives, and to the 
extent permitted by law, each agency shall identify and consider 
regulatory approaches that reduce burdens and maintain flexibility 
and freedom of choice for the public.'' 76 FR 3821 (Jan. 21, 2011).
---------------------------------------------------------------------------

A. Averaging, Banking, and Trading Program

    Averaging, Banking, and Trading (ABT) of emissions credits have 
been an important part of many EPA mobile source programs under CAA 
Title II, including engine and vehicle programs. NHTSA has also long 
had an averaging and banking program for light-duty CAFE under EPCA, 
and recently gained authority to add a trading program for light-duty 
CAFE through EISA. ABT programs are useful because they can help to 
address many issues of technological feasibility and lead-time, as well 
as considerations of cost. They provide manufacturers flexibilities 
that assist the efficient development and implementation of new 
technologies and therefore enable new technologies to be implemented at 
a more aggressive pace than without ABT. ABT programs are more than 
just add-on provisions included to help reduce costs, and can be, as in 
EPA's Title II programs an integral part of the standard setting 
itself. A well-designed ABT program can also provide important 
environmental and energy security benefits by increasing the speed at 
which new technologies can be implemented (which means that more 
benefits accrue over time than with slower-starting standards) and at 
the same time increase flexibility for, and reduce costs to, the 
regulated industry. American Council for an Energy-Efficient Economy 
(ACEEE) has commented that ABT and related flexibilities should not be 
offered for this program because the agencies are not promoting the use 
of new technologies but rather the use of existing technologies. 
However, without ABT provisions (and other related flexibilities), 
standards would typically have to be numerically less stringent since 
the numerical standard would have to be adjusted to accommodate issues 
of feasibility and available lead time. See 75 FR at 25412-13. By 
offering ABT credits and additional flexibilities the agencies can 
offer progressively more stringent standards that help meet our fuel 
consumption reduction and GHG emission goals at a faster pace.
    Section II above describes EPA's GHG emission standards and NHTSA's 
fuel consumption standards. For each of these respective sets of 
standards, the agencies also offer ABT provisions, consistent with each 
agency's statutory authority. The agencies worked closely to design 
these provisions to be essentially identical to each other in form and 
function. Because of this fundamental similarity, the remainder of this 
section refers to these provisions collectively as ``the ABT program'' 
except where agency-specific distinctions are required.
    As discussed in detail below, the structure of the GHG and fuel 
consumption ABT program for HD engines was based closely on EPA's 
earlier ABT programs for HD engines; the program for HD pickups and 
vans was built on the existing light-duty GHG program flexibility 
provisions; and the first-time ABT provisions for combination tractors 
and vocational vehicles are as consistent as possible with EPA's other 
HD vehicle regulations. The flexibility provisions associated with this 
new regulatory category were intended to build systematically upon the 
structure of the existing programs.
    As an overview, ``averaging'' means the exchange of emission or 
fuel consumption credits between engine families or truck families 
within a given manufacturer's regulatory subcategories and averaging 
sets. For example, specific ``engine families,'' which manufacturers 
create by dividing their product lines into groups expected to have 
similar emission characteristics throughout their useful life, would be 
contained within an averaging set.

[[Page 57239]]

Averaging allows a manufacturer to certify one or more engine families 
(or vehicle families, as appropriate) within the same averaging set at 
levels worse than the applicable emission or fuel consumption standard. 
The increased emissions or fuel consumption over the standard would 
need to be offset by one or more engine (or vehicle) families within 
that manufacturer's averaging set that are certified better than the 
same emission or fuel consumption standard, such that the average 
emissions or fuel consumption from all the manufacturer's engine 
families, weighted by engine power, regulatory useful life, and 
production volume, are at or below the level of the emission or fuel 
consumption standard \296\ Total credits for each averaging set within 
each model year are determined by summing together the credits 
calculated for every engine family within that specific averaging set.
---------------------------------------------------------------------------

    \296\ The inclusion of engine power, useful life, and production 
volume in the averaging calculations allows the emissions or fuel 
consumption credits or debits to be expressed in total emissions or 
consumption over the useful life of the credit-using or generating 
engine sales.
---------------------------------------------------------------------------

    ``Banking'' means the retention of emission credits by the 
manufacturer for use in future model year averaging or trading. 
``Trading'' means the exchange of emission credits between 
manufacturers, which can then be used for averaging purposes, banked 
for future use, or traded to another manufacturer.
    In EPA's current HD engine program for criteria pollutants, 
manufacturers are restricted to averaging, banking and trading only 
credits generated by the engine families within a regulatory 
subcategory, and EPA and NHTSA proposed to continue this restriction in 
the GHG and fuel consumption program for engines and vehicles. However, 
the agencies sought comment on potential alternative approaches in 
which fewer restrictions are placed on the use of credits for 
averaging, banking, and trading. Particularly, the agencies requested 
comment on removing prohibitions on averaging and trading between some 
or all regulatory categories in the proposal, and on removing 
restrictions between some or all regulatory subcategories that are 
within the same regulatory category (e.g., allowing trading of credits 
between Class 7 day cabs and Class 8 sleeper cabs).
    The agencies received many comments on the restrictions proposed 
for the ABT program, namely on the proposal that credits could only be 
averaged within the specified vehicle and engine subcategories and not 
averaged across subcategories or between vehicle and engine categories. 
Many commenters, including Union of Concerned Scientist (UCS), NY Dept 
of Transportation, Natural Resources Defense Council, Oshkosh, and 
Autocar, requested that the agencies maintain the restrictions as 
proposed in the NPRM. UCS argued that allowing credits to be used 
across categories could undermine further technology advancements, and 
that manufacturers that have broad portfolios would have advantages 
over those manufacturers that do not. The Center for Biological 
Diversity (CBD) argued that because of the various credit opportunities 
in the ABT program and the potential that manufacturers will pay 
penalties rather than comply with the standards, the program could 
actually cause an increase in emissions and a decrease in fuel 
efficiency. On the other hand, several commenters, including EMA/TMA, 
Cummins, Volvo, and ATA, requested that the agencies maintain the 
proposed restrictions of averaging credits between the engine and 
vehicle categories, but reduce the restrictions on credit averaging 
across vehicle subcategories or engine subcategories or averaging sets 
within similar vehicle and engine weight classes (LHD, MHD and HHD). 
Cummins requested that the agencies allow credit averaging between 
engine subcategories within the same weight classes (LHD, MHD and HHD). 
Cummins explained that tractor and vocational engines in the 
corresponding weight classes not only share the same useful life but 
also use the same emission and fuel consumption technologies and 
therefore should be placed into the same engine averaging set. EMA/TMA 
argued that the NPRM restrictions would inhibit a manufacturer's 
ability to use credits to address market fluctuations, which would 
reduce the flexibility that the ABT program was intended to provide. As 
an example, EMA/TMA stated that if the line-haul market were depressed 
for a period of time a manufacturer could make up any deficit selling 
more low-roof tractors with regional hauling operations. The same 
market shift could eliminate a manufacturer's ability to generate 
credits using its aerodynamic high-roof sleeper cab tractors and could 
create a credit deficit if there is a demand for more of the less 
aerodynamic low-roof tractors. EMA/TMA argued that credit exchanges 
across vehicle categories within the same weight classes within the 
tractor subcategories and across vocational vehicle and tractor 
subcategories would allow a manufacturer more flexibility to deal with 
these types of market and customer demand situations. Finally, several 
commenters, including Ford, DTNA NADA, NTEA and Navistar, requested 
that the agencies reduce the proposed restrictions even further by 
allowing credit averaging between vehicle categories and engine 
categories. Navistar argued that more flexibility was necessary for 
manufacturers like itself to increase innovation at a reasonable cost, 
stating that more restrictions would increase costs within a shorter 
time frame.
    After considering these comments, the agencies continue to believe 
that the ABT program developed by the agencies increases and 
accelerates the technological feasibility of the GHG and fuel 
consumption standards by providing manufacturers flexibility in 
implementing new technologies in a way that may be more consistent with 
their business practices and cost considerations. In response to the 
comments submitted by CBD, the agencies disagree with CBD's statements 
that the ABT program will adversely affect the fuel efficiency and GHG 
emission goals of this regulation. This joint final action requires 
vehicle and engine manufacturers to meet increasingly more stringent 
emission and fuel consumption standards which will result in emission 
reductions and fuel consumption savings. Manufacturers will not have 
the option of not meeting the standards. The ABT program simply 
provides each manufacturer the flexibility to meet these standards 
based upon their individual products and implementation plans.
    By assuming the use of credits for compliance, the agencies were 
able to set the fuel consumption/GHG standards at more stringent levels 
than would otherwise have been feasible. One reason is that use of ABT 
allows each manufacturer maximum flexibility to develop compliance 
strategies consistent with its redesign cycles and with its product 
plans generally, allowing the agencies, in turn, to adopt standards 
which are numerically more stringent in earlier model years than would 
be possible with a more rigid program since those rigidities would be 
associated with greater costs. Greater improvements in fuel efficiency 
will occur under more stringent standards; manufacturers will simply 
have greater flexibility to determine where and how to make those 
improvements than they would have without credit options. Further, this 
is consistent with the directive in EO 13563 to ``seek to identify, as 
appropriate, means to

[[Page 57240]]

achieve regulatory goals that are designed to promote innovation.''
    The agencies further agree that certain restrictions on use of ABT 
which were proposed are unnecessary. The proposed ABT program for 
engines was somewhat more restrictive, in its definition of averaging 
sets, than EPA's parallel ABT program for criteria pollutant emissions 
from the same engines. The final rules conform to the ABT provisions 
for GHG heavy-duty engine emissions to be consistent with the parallel 
ABT provisions for criteria pollutants with same weight engines treated 
as a single averaging set regardless of the vehicles in which they are 
installed. We have applied this same principle with respect to 
combination tractors and vocational vehicles: Treating like weight 
classes as an averaging set. The agencies have determined that these 
additional flexibilities will help to reduce manufacturing costs 
further and encourage technology implementation without creating an 
unfair advantage for manufactures with vertically integrated portfolios 
including engines and vehicles. EPA's experience in administering the 
ABT program for heavy-duty diesel engine criteria pollutant emissions 
supports this conclusion. Therefore, the agencies have decided to allow 
credit averaging within and across vocational vehicle and tractor 
subcategories within the same weight class groups, as well as credit 
averaging across the same weight class vocational and tractor engine 
groups. This added flexibility beyond what was proposed in the NPRM 
will not be extended to the HD pickup truck and van category because 
this group of vehicles is comprised of only one subcategory and is not 
broken down like the other categories and corresponding subcategories 
into different weight classes, and the standard applies to the entire 
vehicle, so that there are no separate engine and vehicle standards. 
Put another way, the HD pickup truck and van category is one large 
averaging set that will remain as proposed.
    However, the agencies are maintaining the restrictions against 
averaging vehicle credits with engine credits or between vehicle weight 
classes or engine subcategories for this first phase of regulation. We 
believe averaging or trading credits between averaging sets would be 
problematic because of the diversity of applications involved. This 
diversity creates large differences in the real world conditions that 
impact lifetime emissions--such as actual operating life, load cycles, 
and maintenance practices. In lieu of conducting extensive and 
burdensome real world tracking of these parameters, along with 
corrective measures to provide some assurance of parity between credits 
earned and credits redeemed, averaging sets provide a reasonable amount 
of confidence that typical engines or vehicles within each set have 
comparable enough real world experience to make such follow-up activity 
unnecessary. The agencies believe this approach will ensure that 
CO2 emissions are reduced and fuel consumption is improved 
in each engine subcategory without interfering with the ability of 
manufacturers to engage in free trade and competition. Again, EPA's 
experience in administering its ABT program for criteria pollutant 
emissions from heavy-duty diesel engines confirms these views. The 
agencies also note that no commenter offered an explanation of why the 
restrictions on this ABT program should differ from the parallel ABT 
program respecting criteria pollutants. As explained earlier in this 
preamble, the agencies intend to re-evaluate the appropriateness of the 
ABT averaging sets and credit use restrictions we are adopting here for 
the HD GHG and fuel consumption program in the future based on 
information we gain implementing this first phase of regulation.
    Under previous ABT programs for other rulemakings, EPA and NHTSA 
have allowed manufacturers to carry forward credit deficits for a set 
period of time--if a manufacturer cannot meet an applicable standard in 
a given model year, it may make up its shortfall by overcomplying in a 
subsequent year. In the NPRM the agencies proposed to allow 
manufacturers of engines, tractors, HD pickups and vans, and vocational 
vehicles to carry forward deficits for up to three years before 
reconciling the shortfall--the same period allowed in numerous other 
EPA rules--but sought comments on alternative approaches for 
reconciling deficits. DTNA supported the three year period and stated 
that it was sufficient for reconciling deficits. CBD did not support 
the use of the carry forward of deficits because it would delay 
investments and technological innovation. The agencies respectfully 
disagree with CBD and believe this provision has enabled the agencies 
to consider overall standards that are more stringent and that will 
become effective sooner than we could consider with a more rigid 
program, one in which all of a manufacturer's similar vehicles or 
engines would be required to achieve the same emissions or fuel 
consumption levels, and at the same time. Therefore the agencies 
included in the final rulemaking the proposed 3 year reconciliation 
period. However, the agencies' respective credit programs require 
manufacturers to use credits to offset a shortfall before credits may 
be banked or traded for additional model years. This restriction 
reduces the chance of manufacturers passing forward deficits before 
reconciling shortfalls and exhausting those credits before reconciling 
past deficits.
    For the heavy-duty pickup and van category, the agencies proposed a 
5-year credit life provision, as adopted in the light-duty vehicle GHG/
CAFE program. Navistar requested that the agencies drop the 5-year 
credit expiration date proposed for the heavy-duty pickup and van 
category and not specify an expiration date for earned credits. 
Navistar stated that such credits are necessary to further improve the 
flexibilities of this program in order to meet the new stringent 
standards within the limited lead time provided. The agencies disagree. 
The 5-year credit life is substantial, and allows credits earned early 
in the phase-in to be held and used without discounting throughout the 
phase-in period.
    For engines, vocational vehicles and tractors, EPA also proposed 
that CO2 credits generated during this first phase of the HD 
National Program could not be used for later phases of standards, but 
NHTSA did not expressly specify the potential expiration of fuel 
consumption credits. DTNA and Cummins requested that the surplus 
credits from the first phase of the program not expire. DTNA suggested 
that the agencies drop any reference to credit expiration until the 
next rulemaking, at which time the agencies would have a better 
understanding of actual credit balances and what kind of lifespan for 
credits might be necessary or appropriate. DTNA argued that in some of 
EPA's past programs, EPA had delayed a final decision about credit 
expiration until development of the subsequent rule when, EPA had a 
better understanding of associated credit balances, along with the 
stringency of the standards being proposed for future model years. EPA 
had proposed to limit the lifespan of credits earned to the first phase 
of standards in the interest of ensuring a level playing field before 
the next phase begins. Upon further consideration, the agencies 
recognize that this is a new program and it is unknown whether any 
manufacturers will have credit surpluses by the end of the first phase 
of standards, much less whether some manufacturers will have 
significantly larger credit surpluses that might create an unlevel 
playing field going into the next phase. The agencies

[[Page 57241]]

are adopting a 5-year credit life provision for all regulatory 
categories, as adopted in the light-duty vehicle program and proposed 
for the HD pickup trucks and vans.\297\
---------------------------------------------------------------------------

    \297\ Note, however, that manufacturers have no property right 
in these credits, so no issues of deprivation of property arise if 
later rules choose not to recognize those credits. See 69 FR at 
39001-002 (June 29, 2004).
---------------------------------------------------------------------------

    The following sections provide further discussions of the 
flexibilities provided in this action under the ABT program and the 
agencies' rationale for providing them.
(1) Heavy-duty Engines
    For the heavy-duty engine ABT program, EPA and NHTSA proposed to 
use six averaging sets per 40 CFR 1036.740 for EPA and 49 CFR 535.7(d) 
for NHTSA, which aligned with the proposed regulatory engine 
subcategories. As described above, the agencies have decided that these 
engine averaging sets should be the same as for criteria pollutants 
under the EPA heavy-duty diesel engine rules, and agree with commenters 
that increasing the size of averaging sets from within subcategories to 
across subcategories within the same engine weight class would provide 
important additional flexibilities for engine manufacturers without 
negatively impacting fuel savings or emissions reductions. The agencies 
are therefore adopting four engine averaging sets rather than the 
proposed six. The four engine averaging sets are light heavy-duty (LHD) 
diesel, medium heavy-duty (MHD) diesel, heavy heavy-duty (HHD) diesel, 
and gasoline or spark ignited engines without distinction for the type 
of vehicle in which the engine is installed. Thus, the final ABT 
program will allow for averaging, banking, and trading of credits 
between HHD diesel engines which are certified for use in vocational 
vehicles and HHD diesel engines which are certified for installation in 
tractors. Similarly, the MHD diesel engines certified for use in either 
vocational vehicles or tractors will be treated as a single averaging 
set. As noted in Section I.G above, the agencies intend to monitor this 
program and consider possibilities of more widespread trading based on 
experience in implementing the program as the first engines and 
vehicles certified to the new standards are introduced. Credits 
generated by engine manufacturers under this ABT program are restricted 
for use only within their engine averaging set, based on performance 
against the standard as defined in Section II.B and II.D. Thus, LHD 
diesel engine manufacturers can only use their LHD diesel engine 
credits for averaging, banking and trading with LHD diesel engines, not 
with MHD diesel or HHD diesel engines. As noted, this limitation is 
consistent with ABT provisions in EPA's existing criteria pollutant 
program for engines and will help avoid problems created by the 
diversity of applications that the broad spectrum of HD engines goes 
into, as discussed above.
    The compliance program for the final rules adopts the proposed 
method for generating a manufacturer's CO2 emission and fuel 
consumption credit or deficit. The manufacturer's certification test 
results would serve as the basis for the generation of the 
manufacturer's Family Certification Level (FCL). The agencies did not 
receive comment on this, and continue to believe that it is the best 
approach. The FCL is a new term we proposed for this program to 
differentiate the purpose of this credit generation technique from the 
Family Emission Limit (FEL) previously used in a similar context in 
other EPA rules. A manufacturer may define its FCL at any level at or 
above the certification test results. Credits for the ABT program are 
generated when the FCL is compared to its CO2 and fuel 
consumption standard, as discussed in Section II. Credit calculation 
for the Engine ABT program, either positive or negative, is based on 
Equation IV-1 and Equation IV-2:

Equation IV-1: Final HD Engine CO2 credit (deficit)

HD Engine CO2 credit (deficit)(metric tons) = (Std - FCL) x 
(CF) x (Volume) x (UL) x (10-6)

Where:
Std = the standard associated with the specific engine regulatory 
subcategory (g/bhp-hr)
FCL = Family Certification Level for the engine family
CF = a transient cycle conversion factor in bhp-hr/mile which is the 
integrated total cycle brake horsepower-hour divided by the 
equivalent mileage of the Heavy-duty FTP cycle. For gasoline heavy-
duty engines, the equivalent mileage is 6.3 miles. For diesel heavy-
duty engines, the equivalent mileage is 6.5 miles. The CF determined 
by the Heavy-duty FTP cycle is used for engines certifying to the 
SET standard.
Volume = (projected or actual) production volume of the engine 
family
UL = useful life of the engine (miles)
10-6 converts the grams of CO2 to metric tons

Equation IV-2: Final HD Engine Fuel Consumption credit (deficit) in 
gallons

HD Engine Fuel Consumption credit (deficit)(gallons) = (Std - FCL) x 
(CF) x (Volume) x (UL) x 10\2\

Where:
Std = the standard associated with the specific engine regulatory 
subcategory (gallon/100 bhp-hr)
FCL = Family Certification Level for the engine family (gallon/100 
bhp-hr)
CF = a transient cycle conversion factor in bhp-hr/mile which is the 
integrated total cycle brake horsepower-hour divided by the 
equivalent mileage of the Heavy-duty FTP cycle. For gasoline heavy-
duty engines, the equivalent mileage is 6.3 miles. For diesel heavy-
duty engines, the equivalent mileage is 6.5 miles. The CF determined 
by the Heavy-duty FTP cycle is used for engines certifying to the 
SET standard.
Volume = (projected or actual) production volume of the engine 
family
UL = useful life of the engine (miles)
10\2\ = conversion to gallons

    To calculate credits or deficits, manufacturers will determine an 
FCL for each engine family they have designated for the ABT program. 
The agencies have defined engine families in 40 CFR 1036.230 and 49 CFR 
535.4 and manufacturers may designate how to group their engines for 
certification and compliance purposes. The FCL may be above or below 
its respective subcategory standard and is used to establish the 
CO2 credits earned in Equation IV-1 or the fuel consumption 
credits earned in Equation IV-2. The final CO2 and fuel 
consumption standards are associated with specific regulatory 
subcategories as described in Sections II.B and II.D (gasoline, light 
heavy-duty diesel, medium heavy-duty diesel, and heavy heavy-duty 
diesel). In the ABT program, engines certified with an FCL below the 
standard generate positive credits and an FCL above the standard 
generates negative credits. As discussed in Section II.B and II.D, 
engine averaging sets that include engine families for which a 
manufacture elects to use the alternative standard of a percent 
reduction from the engine family's 2011 MY baseline are ineligible to 
either generate or use credits. Credit deficits accumulated in an 
averaging set where engine families have used the alternate standard 
can carry that deficit forward for three years following the model year 
for which that deficit was generated at which time the deficit must be 
reconciled with surplus credits.
    The volume used in Equations IV-1 and IV-2 refers to the total 
number of eligible engines sold per family participating in the ABT 
program during that model year. The useful life values in Equation IV-1 
and IV-2 are the same as the regulatory classifications previously used 
for the engine subcategories. Thus, for LHD diesel engines and gasoline 
engines, the useful life values are 110,000 miles; for MHD

[[Page 57242]]

diesel engines, 185,000 miles; and for HHD diesel engines, 435,000 
miles.
    As described in Section II.E above, for purposes of EPA's 
standards, an engine manufacturer may choose to comply with the 
N2O or CH4 cap standards using CO2 
credits.\298\ A manufacturer choosing this option would convert its 
N2O or CH4 test results into CO2eq to 
determine the amount of CO2 credits required. This approach 
recognizes the correlation of these elements in impacting global 
climate change. To account for the different global warming potential 
of these GHGs, manufacturers will determine the amount of 
CO2 credits required by multiplying the shortfall by the 
GWP. For example, a manufacturer would use 25 kg of positive 
CO2 credits to offset 1 kg of negative CH4 
credits. Or a manufacturer would use 298 kg of positive CO2 
credits to offset 1 kg of negative N2O credits. In general 
the agencies do not expect manufacturers to use this provision, but are 
providing it as an alternative in the event an engine manufacturer has 
trouble meeting the CH4 and/or N2O emission caps. 
There are no ABT credits for performance that falls below the 
CH4 cap. As described below, EPA is adopting a provision 
applicable in MYs 2014 through 2016 to allow the creation of 
CO2 credits by demonstrating N2O below the 
current average baseline performance, a value that is well below the 
final N2O cap standard.
---------------------------------------------------------------------------

    \298\ This option does not apply to the NHTSA fuel consumption 
program, since NHTSA is not regulating N2O or 
CH4 emissions, since they are irrelevant to fuel 
consumption reductions.
---------------------------------------------------------------------------

    Manufacturers of engines that generate a credit deficit at the end 
of the model year for any of its averaging sets can carry that deficit 
forward for three years following the model year for which that deficit 
was generated at which time the deficit must be reconciled with surplus 
credits. Manufacturers must use credits once those credits have been 
generated to offset a shortfall before those credits can be banked or 
traded for additional model years. This restriction reduces the chance 
of an engine manufacturer passing forward deficits before reconciling 
their shortfalls and exhausting those credits before reconciling past 
deficits. Deficits will need to be reconciled at the reporting dates 
for model year three. Surplus credits earned in the engine categories 
will expire after five model years. As noted above, the agencies may 
reconsider 5 year credit life during the next phase of rulemaking.
    Under the EPA and NHTSA programs, engine manufacturers are provided 
flexibilities in complying with compression ignition (CI) engine 
standards. These flexibilities are provided in order to: (1) 
Synchronize the implementation schedules for the upcoming EPA OBD 
regulatory changes with the GHG and fuel consumption regulatory 
requirements; (2) aid manufacturers that produce legacy engines in the 
early years of the HD program; and (3) provide an opportunity for 
manufacturers to earn early credits as mentioned in sections 
II.B.(2)(b), II.D.(1)(b)(i) and IV.B.(1) of this document. The 
flexibilities provide manufacturers of CI engines with four different 
and distinct paths that can be followed to meet the EPA and NHTSA 
emission and fuel consumption standards. Manufacturers do not have 
these flexibility mechanisms for gasoline engines, since the standards 
for gasoline engines go into effect after the flexibility mechanisms 
have expired. As a general guideline applicable for each of these four 
compliance paths, if a manufacturer chooses to opt into the NHTSA 
program prior to MY 2017, which is the year the NHTSA compression 
ignition engine standards become mandatory, the path chosen must be the 
same path chosen to meet the EPA emission standards. Each of the four 
paths is discussed below.
    The first path is for a manufacturer to meet the regular or 
``primary'' standards that become mandatory in MY 2014 under the EPA 
regulations. These standards are voluntary in 2014, 2015, and 2016 
under the NHTSA program, and become mandatory in 2017 in the NHTSA 
program. The primary path standards become more stringent in model year 
2017 in both the EPA and NHTSA regulations. For the NHTSA program, an 
engine manufacturer may choose to voluntarily opt into the program 
early, in any of the MYs 2014, 2015 or 2016 allowing that manufacturer 
to earn credits for those model years. In the NHTSA program however, 
once the manufacturer has made the decision to opt into the program 
early it must remain in the program during the subsequent model years.
    Path two allows manufacturers to earn early credits as part of the 
``primary'' MY 2014 emission standard path. Early credits can be earned 
in MY 2013, as discussed in section IV.B.(1). Under the NHTSA fuel 
consumption program, an engine manufacturer may also choose to opt into 
the primary standards program beginning in MY 2013 to obtain early 
credits, but once the decision has been made to opt into the program in 
MY 2013 the manufacturer must remain in the program in the subsequent 
model years. If a manufacturer chooses to opt into the NHTSA program 
prior to the mandatory 2017 model year it must follow that same path 
chosen to meet the EPA emission standards.
    If a manufacturer produces ``legacy'' engines, which typically have 
2011 baseline emissions that are significantly higher than the 2010 
baseline for this regulation, the manufacturer may choose path three. 
This path allows a manufacturer to meet alternate CI engine standards 
in MYs 2014 through 2016 for specific engine families. More details 
about this path are provided in section II.B.(2)(b) and II.D.(1)(b)(i). 
This path can only be taken if all other credit opportunities have been 
exhausted and the manufacturer still cannot meet the primary standards 
under the first path. Again, if a manufacturer chooses this path to 
meet the EPA emission standards in MY 2014-2016, and wants to opt into 
the NHTSA fuel consumption program in these same MYs it must follow the 
exact path followed under the EPA program.
    The fourth path that a CI engine manufacturer can take is referred 
to as the alternative ``OBD phase-in'' path. Manufacturers that wish to 
``bundle'' or combine design changes needed for the 2013 and 2016 
heavy-duty OBD requirements with design changes needed for the GHG and 
fuel consumption requirements may choose this path. The EPA standards 
in this path become mandatory in MY 2013 instead of 2014. In addition, 
in this path emission and fuel consumption standards increase in 
stringency in 2016 rather than in 2017. While the OBD phase-in schedule 
requires engines built in MYs 2013 and 2016 to achieve greater 
reductions than those engines built in the model years under the 
primary program (path one above), it requires lower reductions for 
engines built in 2014 and 2015. Under the NHTSA program, an engine 
manufacturer may choose to opt into the ``OBD phase-in'' path only if 
this is the same path chosen under the EPA program and only if the 
manufacturer is opting into the program in MY 2013 and staying in the 
program through MY 2016. If a manufacturer chooses the OBD phase-in 
path to meet the EPA emission standards and decides to opt into the 
NHTSA program prior to the mandatory MY 2017 requirement, the 
manufacturer must follow the same path under both the EPA and NHTSA 
programs. Under this path the early credit MY 2013 flexibility as 
discussed in path two above is not available. While it does not involve 
credits, the agencies consider the alternative ``OBD phase-in'' path to 
be an additional flexibility.

[[Page 57243]]

    Additional flexibilities for engines, discussed later in Section 
IV.B, provide manufacturers the opportunity to generate early, advanced 
and innovative technology credits.
(2) Heavy-Duty Vocational Vehicles and Tractors
    In addition to the engine ABT program described above, the agencies 
also proposed a heavy-duty vehicle ABT program to facilitate reductions 
in GHG emissions and fuel consumption based on heavy-duty vocational 
vehicle and tractor design changes and improvements. EPA and NHTSA had 
proposed averaging sets which aligned with the proposed twelve 
regulatory subcategories; however in response to the comments 
described, which requested that averaging sets be expanded across 
subcategories within similar weight classes, (analogous to the 
principle on which ABT is structured under EPA's heavy-duty diesel 
engine program for criteria pollutants), the agencies are finalizing 
only three averaging sets--LHD, MHD, and HHD based upon the three 
weight classes. In other words, all HHD (Class 8) tractors, HHD 
vocational tractors, and HHD vocational vehicles will be treated as a 
single averaging set. Similarly, all MHD (Class 7) tractors, MHD 
vocational tractors, and MHD (Class 6-7) vocational vehicles will be 
treated as a single averaging set, and LHD vocational vehicles (Class 
2b-5) will be treated as a single averaging set. For this category, the 
structure of the final ABT program should create incentives for vehicle 
manufacturers to advance new, clean technologies, or existing 
technologies earlier than they otherwise would. ABT provides 
manufacturers the flexibility to deal with unforeseen shifts in the 
marketplace that affect sales volumes. At the same time, restricting 
trading to within these segments gives the agencies confidence that the 
reductions are truly offsetting given the similarity in products 
engaged in trading. This structure also allows for a straightforward 
compliance program for each sector, with aspects that are independently 
quantifiable and verifiable.
    Credit calculation for the final HD Vocational Vehicle and Tractor 
CO2 and fuel consumption credits, either positive or 
negative, will be generated according to Equation IV-3 and Equation IV-
4:

Equation IV-3: The Final HD Vocational Vehicle and Tractor 
CO2 credit (deficit)

HD Vocational Vehicle and Tractor CO2 credit 
(deficit)(metric tons) = (Std - FEL) x (Payload Tons) x (Volume) x (UL) 
x (10-6)

Where:
Std = the standard associated with the specific regulatory 
subcategory (g/ton-mile)
Payload tons = the prescribed payload for each class in tons (12.5 
tons for Class 7 tractors, 19 tons for Class 8 tractors, 2.85 tons 
for LHD vocational, 5.6 tons for MHD vocational, and 7.5 tons for 
HHD vocational vehicles)
FEL = Family Emission Limit for the vehicle family which is equal to 
the output from GEM (g/ton-mile)
Volume = (projected or actual) production volume of the vehicle 
family
UL = useful life of the vehicle (435,000 miles for HHD, 185,000 
miles for MHD, and 110,000 miles for LHD)
10-6 converts the grams of CO2 to metric tons

Equation IV-4: Final HD Vocational Vehicle and Tractor Fuel Consumption 
credit (deficit) in gallons

HD Vocational Vehicle and Tractor Fuel Consumption Credit (deficit) 
(gallons) = (Std - FEL) x (Payload Tons) x (Volume) x (UL) x 10\3\

Where:
Std = the standard associated with the specific regulatory 
subcategory (gallons/1,000 ton-mile)
Payload tons = the prescribed payload for each class in tons (12.5 
tons for Class 7 tractors, 19 tons for Class 8 tractors, 2.85 tons 
for LHD vocational, 5.6 tons for MHD vocational, and 7.5 tons for 
HHD vocational vehicles)
FEL = Family Emission Limit for the vehicle family (gallons/1,000 
ton-mile)
Volume = (projected or actual) production volume of the vehicle 
family
UL = useful life of the vehicle (435,000 miles for HHD, 185,000 
miles for MHD, and 110,000 miles for LHD)
10\3\ = conversion to gallons

    Manufacturers of vocational vehicles and tractors that generate a 
credit deficit at the end of the model year for any of its averaging 
sets can carry that deficit forward for three years following the model 
year for which that deficit was generated at which time the deficit 
must be reconciled with surplus credits. Manufacturers must use credits 
once those credits have been generated to offset a shortfall before 
those credits can be banked or traded for additional model years. This 
restriction reduces the chance of a vehicle manufacturer passing 
forward deficits before reconciling their shortfalls and exhausting 
those credits before reconciling past deficits. Deficits will need to 
be reconciled at the reporting dates for model year three. Surplus 
credits earned in the vehicle categories will have a five year 
expiration date. The agencies may reconsider the 5 year credit life 
during the next phase of the rulemaking.
    Additional flexibilities for HD vocational vehicles and tractors, 
discussed later in Section IV.B, provide manufacturers the opportunity 
to generate early, advanced, and innovative technology credits.
(3) Heavy-Duty Pickup Truck and Van Flexibility Provisions
    The NPRM included specific flexibility provisions for manufacturers 
of HD pickups and vans, similar to provisions adopted in the recent 
rulemaking for light-duty car and truck GHGs and fuel economy. The 
agencies are finalizing the flexibilities as proposed. In the heavy-
duty pickup and van category a manufacturer's credit or debit balance 
will be determined by calculating their fleet average performance and 
comparing it to the manufacturer's CO2 and fuel consumption 
standards, as determined by their fleet mix, for a given model year. A 
target standard is determined for each vehicle. These targets, weighted 
by their associated production volumes, are summed at the end of the 
model year to derive the production volume-weighted manufacturer annual 
fleet average standard. A manufacturer will generate credits if its 
fleet average CO2 or fuel consumption level is lower than 
its standard and will generate debits if its fleet average 
CO2 or fuel consumption level is above that standard. To 
receive the benefit of the advanced technology provisions, if the 
manufacturer's fleet includes conventional and advanced technology 
vehicles, the manufacturer will divide this fleet of vehicles into two 
separate fleets for calculation of fleet average credits. The end-of-
year reports will provide the appropriate data to reconcile pre-
compliance estimates with final model year figures (see 40 CFR 1037.730 
and 49 CFR 535.8).
    The EPA credit calculation is expressed in metric tons and 
considers production volumes, the fleet standards and performance, and 
a factor for the vehicle useful life, as in the light-duty GHG program. 
The NHTSA credit calculation uses the fleet standard and performance 
levels in fuel consumption units (gallons per 100 miles), as opposed to 
fuel economy units (mpg) as done in the light-duty program, along with 
the vehicle useful life, in miles, allowing the expression of credits 
in gallons. The total model year fleet credit (debit) calculations will 
use the following equations:

CO2 Credits (Mg) = [(CO2 Std - CO2 
Act) x Volume x UL] / 1,000,000

[[Page 57244]]

Fuel Consumption Credits (gallons) = (FC Std - FC Act) x Volume x UL x 
100

Where:
CO2 Std = Fleet average CO2 standard (g/mi)
FC Std = Fleet average fuel consumption standard (gal/100 mile)
CO2 Act = Fleet average actual CO2 value (g/
mi)
FC Act = Fleet average actual fuel consumption value (gal/100 mile)
Volume = the total production of vehicles in the regulatory category
UL = the useful life for the regulatory category (miles)

    As described above, HD pickup and van manufacturers will be able to 
carry forward deficits from their fleet-wide average for three years 
before reconciling the shortfall. Manufacturers will be required to 
provide a plan in their pre-model year reports showing how they will 
resolve projected credit deficits. However, just as in the engine 
category, manufacturers will need to use credits earned once those 
credits have been generated to offset a shortfall before those credits 
can be banked or traded for additional model years. This restriction 
reduces the chance of vehicle manufacturers passing forward deficits 
before reconciling their shortfalls and exhausting those credits before 
reconciling past deficits. Deficits will need to be reconciled at the 
reporting dates for model year three. Surplus credits earned in the HD 
pickup and van categories (like surplus credits for all the other 
subcategories) will have a five year expiration date. The agencies may 
reconsider the 5 year credit life during the next phase of the 
rulemaking.
    Additional flexibilities for heavy-duty pickup and van category are 
discussed below in Section IV.B which provides manufacturers the 
opportunity to generate early, advanced and innovative technology 
credits.

B. Additional Flexibility Provisions

    The agencies proposed additional provisions to facilitate 
reductions in GHG emissions and fuel consumption beginning in the 2014 
model year. While EPA and NHTSA believed the ABT and flexibility 
structure would be sufficient to encourage reduction efforts by heavy-
duty highway engine and vehicle manufacturers, the agencies understood 
that other efforts could create additional opportunities for 
manufacturers to reduce their GHG emissions and fuel consumption. These 
provisions would provide additional incentives for manufacturers to 
innovate and to develop new strategies and cleaner technologies. The 
agencies requested comment on these provisions, as described below.
(1) Early Credit Option
    The agencies proposed that manufacturers of HD engines, HD pickup 
trucks and vans, combination tractors, and vocational vehicles be 
eligible to generate early credits if they demonstrate improvements in 
excess of the standards prior to the model year the standards become 
effective. As an example, if a manufacturer's MY 2013 subcategory of 
tractors exceeds the EPA mandatory MY 2014 standard for those same 
vehicles, then that manufacturer could claim MY 2013 credits or ``early 
credits'' to utilize in its ABT program starting in the MY 2014. As 
noted in the NPRM, the start dates for EPA's GHG standards and NHTSA's 
fuel consumption standards vary by regulatory category (see Section II 
for the model years when the standards become effective), meaning that 
the early credits provision, if selected by a manufacturer, could begin 
during different model years. The NPRM stated that manufacturers would 
need to certify their engines or vehicles to the standards at least six 
months before the start of the first model year of the mandatory 
standards and that limitations on the use of credits in the ABT 
programs--i.e., limiting averaging to within each vehicle or engine 
averaging set--would apply for the early credits as well. In the NPRM, 
NHTSA and EPA requested comment on whether a credit multiplier, 
specifically a multiplier of 1.5, would be appropriate to apply to 
early credits from HD engines, combination tractors, and vocational 
vehicles (but not to early credits from HD pickups and vans), as a 
greater incentive for early compliance. See 75 FR at 74255.
    The agencies received comments from Cummins, DTNA, EMA/TMA, 
Navistar, Eaton, Bosch, CBD and CALSTART relating to these early credit 
provisions. All of these commenters supported the early credit 
provision for the most part, but many requested that the agencies 
eliminate some of the restrictions relating to this provision. EMA/TMA 
argued that MY 2012 should also be considered for early credits and 
that the requirement to certify six months before the start of the 
first model year would unnecessarily restrict manufacturers from 
earning credits for technology introduced within six months of the 
respective model year. In addition, EMA/TMA stated that requiring 
certification of the entire averaging set instead of individual vehicle 
configurations would not allow for early introduction of new 
technologies. Cummins stated that the six month lead time requirement 
should be removed and that manufacturers be allowed to earn early 
credits for individual engine families rather than only for the entire 
averaging set, stating that removal of these restrictions would further 
benefit the environment. CBD stated that early credits should only be 
granted if the emission and fuel consumption benefits are in addition 
to or above the existing performance levels and are quantifiable and 
verifiable.
    EPA and NHTSA have reviewed these comments and decided to clarify 
the proposed early credit provisions to account for the above concerns. 
Early credits are intended to be an incentive to manufacturers to 
introduce more efficient engines and vehicles earlier than they 
otherwise would be. However, the agencies do not want to provide a 
windfall of credits to manufacturers that may already have one or more 
products that meet the standards. Therefore, the final rules include 
the option for a manufacturer to obtain early credits for products if 
they certify their entire subcategory at GHG emissions and fuel 
consumption levels below the standards. See 75 FR at 74255. Thus, for 
example, early credits could be generated for all HHD engines installed 
in combination tractors. The agencies are making a clarification in 
this action that the manufacturers must certify their entire 
subcategory, not necessarily their entire averaging set, because the 
averaging sets are broadened under the final rulemaking from the 
categories proposed in the NPRM. In addition, the agencies are 
providing the flexibility for combination tractor manufacturers to 
obtain early credits for their additional sales, as compared to their 
2012 model year sales, of SmartWay designated combination tractors 
(which includes high roof sleeper cabs only) in 2013 model year. The 
agencies view this subcategory of vehicles as the only segment of 
vehicles or engines where the true additional reductions due to the 
early credits can be quantified outside of certifying an entire 
subcategory, because the benefit is tied directly to the increase in 
the SmartWay vehicles manufactured in MY 2013 in excess of those 
manufactured in MY 2012.
    A manufacturer may opt to apply for early credits from their 2013 
model year SmartWay designated combination tractor sales by first 
calculating the difference between the number of SmartWay designated 
combination tractors sold in 2012 MY versus 2013 model year. The 
increment in sales determines the number of 2013 model year SmartWay 
designated tractors which can be used to certify for early credits, at 
the manufacturer's choice of which vehicles to consider. The

[[Page 57245]]

manufacturer would then determine each tractor configuration's 
performance by modeling in GEM, using each vehicle configuration's 
appropriate inputs for coefficient of drag, tire rolling resistance, 
idle reduction, weight reduction, and vehicle speed limiter. Next, the 
difference between a specific tractor configuration's performance and 
the 2014 MY standard for the appropriate regulatory subcategory (e.g., 
Class 8 sleeper cab high roof tractors) would be calculated. The 
CO2 and fuel consumption credits are calculated using 
Equation IV-4 and IV-5.
    As discussed above and in Section II, manufacturers may opt into 
the NHTSA voluntary program prior to when the program becomes 
mandatory. Manufacturers that opt in become subject to NHTSA standards 
for all regulatory categories. This provides manufacturers the option 
of complying with NHTSA fuel consumption standards equivalent to the 
EPA emission standards in order to accumulate credits in the ABT 
program. If a manufacturer opts into the EPA early credit program, it 
may also opt into an equivalent NHTSA early credit program. In this 
case, the manufacturer must enter the program concurrently with the EPA 
program and will be subject to the full MY 2014-2015/2016 NHTSA 
voluntary program. NHTSA would like to clarify that for the early 
credit provision, implementation must occur in MY 2013 exactly as 
implemented under the EPA emission program, and not in the model year 
immediately before the NHTSA standards become mandatory (since 
otherwise manufacturers would generate credits under the fuel 
consumption program as a result of complying with mandatory GHG 
standards--a windfall). Further, once a manufacturer opts into the 
NHTSA program it must stay in the program for all the optional MYs and 
remain standardized with the implementation approach being used to meet 
the EPA emission program. EPA and NHTSA intend for manufacturers' ABT 
credit balances to remain equivalent wherever possible.
    The agencies also received comments from EMA/TMA and Cummins 
opposing the requirement to certify six months prior to the first model 
year of the mandatory standards for early credits. The commenters 
argued and the agencies agree that this restriction could cause some 
delays in technology rollout and are therefore not adopting this 
provision. The agencies reviewed the restriction and evaluated the 
light-duty 2012-2016 MY vehicle early credit program. No such 
restriction exists for LD vehicles. We therefore believe that this 
requirement is not necessary for our implementation of the program. In 
addition, we are adopting a provision which allows manufacturers to 
generate early credits for certifying less than a full model year 
early.
    Several commenters, including DTNA, Edison Electric Institute, 
Eaton, and Bosch, supported using a 1.5 multiplier for early credits, 
stating that it would encourage early introduction of technology. 
Cummins and UCS opposed the multiplier stating that the opportunity to 
earn credits at their normal value should be sufficient incentive for 
early compliance. The agencies believe that this incentive will further 
encourage faster implementation of emission and fuel savings technology 
and help to reduce the costs manufacturers will incur in efforts to 
comply with these rules. The agencies have therefore decided to 
finalize a 1.5 multiplier for early credits earned in MY 2013.\299\ 
However, the agencies note that manufacturers may not apply an 
additional 1.5 multiplier for advanced technology credits which are 
also certified as early credits.
---------------------------------------------------------------------------

    \299\ There is no multiplier for the early credit provisions in 
the light-duty vehicle rule. However, the situation there was more 
complicated, since early credits needed to be correlated with credit 
opportunities under the California GHG program for light-duty 
vehicle, and also needed to be integrated with statutory credits 
under EPCA/EISA for flexible fuel vehicles. See 75 FR at 25440-443. 
Thus, the light-duty vehicle rule early credit provisions are not 
analogous to those adopted in this rule for the heavy duty sector.
---------------------------------------------------------------------------

    With respect to heavy-duty pickups and vans, the agencies proposed 
that early credits could be generated on a fleetwide basis by 
comparison of the manufacturer's 2013 heavy-duty pickup and van fleet 
with the manufacturer's fleetwide targets, using the target standards 
equations for the 2014 model year. 75 FR at 74255. The agencies are 
finalizing these provisions as proposed. Under the structure for the 
fleet average standards, this credit opportunity entails certifying a 
manufacturer's entire HD pickup and van fleet in model year 2013. 
Industry commenters argued that early credits should be calculated 
against a target curve that is less stringent than the 2014 curve. We 
disagree. Because it is the first year of a 5-year phase-in, the 2014 
model year has quite modest emissions and fuel consumption reductions 
targets of only 15 percent of the 2018 model year standards stringency. 
Targeting even less significant improvements over the baseline would 
unduly increase the prospect for windfall credits by individual 
manufacturers who may have better than average baseline fleets. On the 
other hand, we are confident that the early credit program, based as it 
is on full fleet compliance with the MY 2014 targets, will not result 
in windfall credits as it represents, in effect, a complete bringing 
forward of the program start date by one model year for manufacturers 
who choose to pursue it. Again, the agencies consider the availability 
of early credits to be a valuable complement to the overall program to 
the extent that they encourage early implementation of effective 
technologies.
(2) Advanced Technology Credits
    The NPRM proposed targeted provisions that were expected to promote 
the implementation of advanced technologies. Specifically, 
manufacturers that incorporate these technologies would be eligible for 
special credits that could be applied to other heavy-duty vehicles or 
engines, including those in other heavy-duty categories. The credits 
are thus `special' in that they can be applied across the entire heavy-
duty sector, unlike the ABT and early credits discussed above and the 
innovative technology credits discussed in the following subsection. 
The eligible technologies were:
     Hybrid powertrain designs that include energy storage 
systems.
     Rankine cycle engines.\300\
---------------------------------------------------------------------------

    \300\ Although as noted in Section III above and in Chapter 2 of 
the RIA, this technology is still under development and so is not 
presently available.
---------------------------------------------------------------------------

     All-electric vehicles.
     Fuel cell vehicles.
    NHTSA and EPA requested comment on the list of technologies 
identified as advanced technologies and whether additional technologies 
should be added to the list. In addition to the increased fungibility 
of advanced technology credits, NHTSA and EPA requested comment on 
whether a credit multiplier, specifically a multiplier of 1.5, would be 
appropriate to apply to advanced technology credits, as a greater 
incentive for the technologies' introduction. See 75 FR at 74255.
    MEMA asked that the agencies expand the list of technologies that 
are eligible for Advanced Technology Credits to include advanced 
transmission and drivetrain technologies, tire and wheel accessories, 
and advanced engine accessories technologies (such as electronic air 
control systems and clutched turbocharged air compressor). Bendix 
requested that weight reduction approaches, improved transmission and 
drivetrains, driver management and coaching, and tire and wheel 
improvements be allowed to receive

[[Page 57246]]

credit through the Advanced Technology Credit Program.
    The advanced technology credit program is intended to encourage 
development of technologies that are not yet commercially available. In 
order to provide incentives for the research and development needed to 
introduce these technologies, Advanced Technology Credits can be 
applied to any heavy-duty vehicle or engine and are not limited to the 
vehicle or engine categories generating the credit. Because of this 
flexibility in the application of these credits, it is important that 
the list of eligible technologies only include technologies that are 
not yet available in the market. In addition, the technologies must 
lend themselves to straight forward methodologies for quantifying 
emissions and fuel consumption reductions. For some of the technologies 
that MEMA and Bendix asked be included in the program, such as 
electrified accessories and improved tires, the agencies have already 
established a mechanism for quantifying reductions associated with 
these approaches. For example, the agencies assumed in the regulatory 
impact analysis that some electrified accessories will be used to 
comply with the regulations. Specifically, improved water and oil pumps 
are assumed to be used for 2014 LHD, MHD, and HHD FTP and SET diesel 
engines to comply with standards and if used, their performance would 
be assessed in the engine certification process. (See RIA Chapter 2.4). 
Any reductions in engine load and resulting emissions and fuel 
consumption resulting from accessory electrification thus will be 
accounted for in engine dynamometer testing. However, other electrified 
accessories, such as air conditioning do not impact engine operation 
over the FTP and SET cycles. As such, we are allowing credit for 
tailpipe AC emissions (as opposed to AC leakage) to be established 
through the Innovative Technology Credit Program described in section 
IV.B(3) below. With regard to tire rolling resistance improvements, 
light weight wheels, and weight reduction associated with the use of 
super single tires, these are already part of the technology basis for 
the standard for combination tractors and are accounted for in the GEM, 
and are also part of the technology basis for the standards for heavy-
duty pickups and vans (See RIA Chapter 2.3). Some improved 
transmissions--such as automatic manuals--have been available 
commercially for ten years and as such, does not meet the criteria to 
be included on the list of advanced technologies. However, as described 
in Section IV.B.(3), advanced transmissions and drivetrains could be 
eligible for credits in the Innovative Technology Credit Program, and 
the agencies acknowledge the importance of including advanced 
transmissions and drivetrains in the program. With regard to weight 
reduction, the agencies are allowing additional weight reduction 
approaches to be used for tractors through modeling using GEM and 
through the innovative technology program. And finally, for driver 
management and coaching--while we recognize that there could be 
significant benefits to this, the difficulty in establishing a baseline 
condition for driver behavior limits the agencies' ability to establish 
a reduction for this approach at this time.
    The agencies have decided not to change the proposed list of 
technologies evaluated as advanced technologies, but are providing 
additional clarity in the advanced technology list. The agencies 
proposed that Rankine cycle engines be included, but the agencies are 
adopting the wording of Rankine cycle waste heat recovery system 
attached to an engine.
    The agencies received comments from Bendix, Bosch, MEMA, Navistar, 
Odyne, Green Truck Association, Eaton, ArvinMeritor and Calstart, which 
supported the 1.5 multiplier for advanced technology credits. MEMA 
argued that these added flexibilities are absolutely necessary to help 
advanced technologies penetrate the marketplace and are the primary 
impetus to integrate these technologies onto vehicles. The agencies 
also received comments from several stakeholders, including ACEEE and 
Cummins opposing the 1.5 multiplier for advanced technology credits. 
ACEEE argued that multipliers should be avoided because they lessen the 
total emission reductions by allowing a greater increase in the 
emissions of other vehicles than they offset. After reviewing these 
comments, the agencies have determined that the relatively low volumes 
expected in this time frame are likely to mitigate any potential 
dilution of environmental benefits and be outweighed by the benefits of 
introduction of advanced technology into the heavy-duty sector. 
Further, the credit multiplier will provide enough added benefit to the 
nascent heavy-duty hybrid community to help reduce barriers to market 
entry for new technologies. Therefore, the final rules include a 
multiplier of 1.5 for advanced technology credits. However, the 
agencies are also capping the amount of advanced credits that can be 
brought into any averaging set into any model year at 60,000 Mg to 
prevent market distortions.
(a) HD Pickup Truck and Van Hybrids and all Electric Vehicles
    For HD pickup and van hybrids, the agencies proposed that testing 
would be done using adjustments to the test procedures developed for 
light-duty hybrids. See 75 FR at 74255. NHTSA and EPA also proposed 
that all-electric and other zero tailpipe emission vehicles produced in 
model years before 2014 be able to earn credits for use in the 2014 and 
later HD pickup and van compliance program, provided the vehicles are 
covered by an EPA certificate of conformity for criteria pollutants. 
These credits would be calculated based on the 2014 diesel standard 
targets corresponding to the vehicle's work factor, and treated as 
though they were earned in 2014 for purposes of credit life. 
Manufacturers would not have to early-certify their entire HD pickup 
and van fleet in a model year as for other early-complying vehicles.
    NHTSA and EPA also proposed that model year 2014 and later EVs and 
other zero tailpipe emission vehicles be factored into the fleet 
average GHG and fuel consumption calculations based on the diesel 
standards targets for their model year and work factor. A manufacturer 
also has the option to subtract these vehicles out of its fleet and 
determine their performance as advanced technology credits that can be 
used for all other HD vehicle categories, but these credits would, of 
course, not then be reflected in the manufacturer's pickup and van 
category credit balance. Commenters generally supported the 
introduction of hybrid and zero tailpipe emission vehicles, but did not 
comment on the specific provisions discussed above. The agencies also 
proposed in determining advanced technology credits for electric and 
zero emission vehicles that in the credits equation the actual 
emissions and fuel consumption performance be set to zero (i.e. that 
emissions be considered on a tailpipe basis exclusively). We are 
finalizing these provisions as proposed.
    The proposal also solicited comment on the accounting of upstream 
GHG emissions. Some commenters argued that EPA should maintain its 
traditional focus in mobile source rulemakings on vehicle tailpipe 
emissions and leave the consideration of GHG emissions from upstream 
fuel production and distribution-related sources such as refineries and 
power plants to EPA regulatory programs which could focus specifically 
on those sources. Others argued that, since EPA accounts for upstream 
GHG emissions in its benefits assessments, the agency should reflect

[[Page 57247]]

upstream GHG emissions impacts in vehicle compliance values as well. 
After considering these comments, the agencies have decided to base the 
credit accounting on tailpipe emissions only. The agencies believe that 
introduction of EV technology into the heavy-duty pickup and van sector 
in these model years will be limited and that incentives are important 
to encourage such introduction. Similarly, the agencies believe that 
use of EV technology for these vehicles in these model years will be 
infrequent so that there is no need to adopt a cap whereby upstream 
emissions would be counted after a certain volume of sales. See 75 FR 
at 25434-438 (adopting such a cap for light-duty vehicles under the 
2012-2016 MY GHG standards). We also recognize that the ongoing EPA/
NHTSA rulemaking to reduce GHGs and fuel consumption in MY 2017 and 
later light-duty vehicles is examining this issue, and may yield 
information and policy direction relevant to the planned follow-on 
rulemaking for the heavy-duty sector.
(b) Vocational Vehicle and Tractor Hybrids
    For vocational vehicles or combination tractors incorporating 
hybrid powertrains, we proposed two methods for establishing the number 
of credits generated--chassis dynamometer and engine dynamometer 
testing--each of which is discussed next. As discussed in the NPRM the 
agencies are not aware of models that have been adequately peer 
reviewed with data that can assess this technology without the 
conclusion of a comparison test of the actual physical product.
(i) Chassis Dynamometer Evaluation
    For hybrid certification to generate credits we proposed to use 
chassis testing as an effective way to compare the CO2 
emissions and fuel consumption performance of conventional and hybrid 
vehicles. See 75 FR at 74256. We proposed that heavy-duty hybrid 
vehicles be certified using ``A to B'' vehicle chassis dynamometer 
testing. This concept allows a hybrid vocational vehicle manufacturer 
to directly quantify the benefit associated with use of its hybrid 
system on an application-specific basis. The concept would entail 
testing the conventional vehicle, identified as ``A'', using the cycles 
as defined in Section V. The ``B'' vehicle would be the hybrid version 
of vehicle ``A''. The ``B'' vehicle would need to be the same exact 
vehicle model as the ``A'' vehicle. As an alternative, if no specific 
``A'' vehicle exists for the hybrid vehicle that is the exact vehicle 
model, the most similar vehicle model would need to be used for 
testing. We proposed to define the ``most similar vehicle'' as a 
vehicle with the same footprint, same payload, same testing capacity, 
the same engine power system, the same intended service class, and the 
same coefficient of drag. We did not receive any adverse comments to 
this approach and are therefore adopting the same criteria as proposed.
    To determine the benefit associated with the hybrid system for GHG 
performance, the weighted CO2 emissions results from the 
chassis test of each vehicle would define the benefit as described 
below:
    1. (CO2--A - CO2--B)/(CO2--A) = --
-- (Improvement Factor)
    2. Improvement Factor x GEM CO2 Result--B = ------ (g/
ton mile benefit)
    Similarly, the benefit associated with the hybrid system for fuel 
consumption would be determined from the weighted fuel consumption 
results from the chassis tests of each vehicle as described below:
    3. (Fuel Consumption--A--Fuel Consumption--B)/(Fuel Consumption--A) 
= ------ (Improvement Factor)
    4. Improvement Factor x GEM Fuel Consumption Result--B = ------ 
(gallon/1,000 ton mile benefit)
    The credits for the hybrid vehicle would be calculated as described 
in the ABT program except that the result from Equation 2 and Equation 
4 above replaces the (Std-FEL) value.
    The agencies proposed two sets of duty cycles to evaluate the 
benefit depending on the vehicle application to assess hybrid vehicle 
performance--without and with PTO systems. The key difference between 
these two sets of vehicles is that one set (e.g., delivery trucks) does 
not operate a PTO while the other set (e.g., bucket and refuse trucks) 
does.
    The first set of duty cycles would apply to the hybrid powertrains 
used to improve the motive performance of the vehicles without a PTO 
system (such as pickup and delivery trucks). The typical operation of 
these vehicles is very similar to the overall drive cycles final in 
Section II. Therefore, the agencies are finalizing to use the same 
vehicle drive cycle weightings for testing these vehicles, as shown in 
Table IV-1.

                    Table IV-1--Final Drive Cycle Weightings for Hybrid Vehicles Without PTO
----------------------------------------------------------------------------------------------------------------
                                                                Transient
                                                                (percent)     55 mph (percent)  65 mph (percent)
----------------------------------------------------------------------------------------------------------------
Vocational Vehicles.......................................               75%                9%               16%
Day Cab Tractors..........................................               19%               17%               64%
Sleeper Cab Tractors......................................                5%                9%               86%
----------------------------------------------------------------------------------------------------------------

    The second set of duty cycles apply to testing hybrid vehicles used 
in applications such as utility and refuse trucks which tend to have 
additional benefits associated with use of stored energy, in terms of 
avoiding main engine operation and related CO2 emissions and 
fuel consumption during PTO operation. To appropriately address 
benefits, exercising the conventional and hybrid vehicles using their 
PTO would help to quantify the benefit to GHG emissions and fuel 
consumption reductions. The duty cycle proposed to quantify the hybrid 
CO2 and fuel consumption impact over this broader set of 
operation was the three primary drive cycles plus a PTO duty cycle. The 
PTO duty cycle as proposed took into account the sales impact and 
population of utility trucks and refuse haulers. As described in RIA 
Chapter 3, the agencies proposed to add an additional PTO cycle to 
measure the improvement achieved for this type of hybrid powertrain 
application. The agencies welcomed comments on the final drive cycle 
weightings and the final PTO cycle.
    The agencies received comments from Cummins stating that the 
proposed weighting of the PTO cycle used a time-based weighting instead 
of a VMT-based weighting. For the final rules, the agencies derived new 
PTO cycle weighting by calculating the average speed of a vehicle 
during the motive portion of its operation, as detailed in RIA Chapter 
3.7.1.1. The average speed is used in a conversion factor to convert 
the emissions from the PTO operation

[[Page 57248]]

measured in grams per hour into grams per ton-mile. A number of 
comments were received on the proposed hybrid chassis testing approach.
    The agencies received comments from engine manufacturers, hybrid 
manufacturers, and industry associations, as well as non-governmental 
organizations related to proper characterization of hybrid performance. 
To address concerns raised by commenters regarding hybrid testing 
several updates have been made to clarify a hybrid engine and/or system 
for pre-transmission, post-transmission, and chassis dynamometer 
testing. As described in 40 CFR 1036.801, a hybrid engine or hybrid 
power train means an engine or powertrain that includes energy storage 
features other than a conventional battery system or conventional 
flywheel. Supplemental electrical batteries and hydraulic accumulators 
are examples of hybrid energy storage systems. A hybrid vehicle is 
defined in 40 CFR 1037.801 and it means a vehicle that includes energy 
storage features (other than a conventional battery system or 
conventional flywheel) in addition to an internal combustion engine or 
other engine using consumable chemical fuel. The duty cycles used for 
testing hybrid systems as either the post-transmission or complete 
chassis configuration will be retained from the proposal, however the 
weighting factors have been adjusted so that the performance of 
applications expected to be hybridized in the near term is better 
reflected. The testing provisions for evaluating the performance 
including the driver model definition, vehicle model, and overall cycle 
performance have been enhanced as described in 40 CFR 1036.525 and 40 
CFR 1037.525. Additionally, provisions for evaluating power take-off 
performance improvement have been addressed for charge-sustaining 
testing. For those hybrid systems which utilize shore power (e.g. plug-
in hybrids), an innovative technology approach in which the certifier 
characterizes the performance associated with the operation of the 
system in a charge-depleting and charge-sustaining mode is most 
appropriate given the potential for variability in performance between 
applications and system designs. To address the issue of parity between 
methods it should be clarified that the approach taken for hybrid 
testing is consistent for chassis cycle based testing. This method used 
for both post-transmission and complete vehicle chassis testing is the 
development of an improvement factor which is then related to the base 
system performance. The pre-transmission approach relies on work based 
assessment of performance as with the current engine standards.
    Comments were received from EMA/TMA, ACEEE, stating that the hybrid 
definition and test methodology needs to be more clearly defined. 
Cummins and EMA/TMA asked that the control volumes for the chassis test 
procedure be specified. Allison stated that the baseline configuration 
in A to B testing needs clarification--as an example they said it is 
not clear if the baseline vehicle needs to be the same model year as 
the hybrid configuration. They added that it is unclear how to account 
for hotel or accessory loads.
    EMA/TMA, Allison, Odyne, and American Trucking Association said 
that the hybrid drive cycles do not match real world hybrid 
applications, and as such, will result in an underestimation of 
benefits resulting from hybrid use. Some or all of these commenters 
asked that a hybrid drive cycle be developed that consists mainly of 
transient cycle, increased idle time, low steady state operation, and 
high acceleration and deceleration rates. EMA/TMA said the proposed 
cycle--the CARB heavy-heavy duty truck transient mode cycle, was 
developed as a composite cycle based on a wide range of medium- and 
heavy-duty vehicles but does not reflect the high acceleration and 
deceleration of vehicles used in urban applications and which is 
typical for hybrid vehicles and does not reflect the level of 
acceleration and deceleration typical of hybrids. Eaton asked that the 
agencies establish four separate test cycles for hybrids rather than 
two that more closely match what actual hybrids do in use. Hino said 
that energy recapture from regenerative braking needs to be built into 
the test cycle and as currently designed it is not. Hino also urged the 
agencies to create test cycles that capture variations in different 
types of hybrids. Cummins said that more representative vehicle test 
cycles should be developed based on the FTP and SET to ensure that the 
test cycles are functionally equivalent between vehicles and engines to 
ensure fair evaluation of the technology. ICCT articulated the same 
point on the need for parity between engine and vehicle test cycles.
    EMA/TMA, DTNA, and Cummins asked that manufacturers not be required 
to conduct coastdown testing for hybrid vehicles to establish road 
loads for each type of vehicle. Instead, they asked that the agencies 
define default road load values for manufacturers to use for hybrids. 
EMA/TMA said that conducting coastdown tests is expensive. They also 
argued that road load is irrelevant to determining hybrid performance 
since the chassis dynamometer method requires a comparison of a vehicle 
that is identical in all respects except those factors directly 
relating to the hybrid powertrain.
    Cummins, ICCT, and Center for Clean Air Policy expressed general 
support for chassis dynamometer testing. Allison said that the lack of 
dynamometer infrastructure could limit the ability of manufacturers to 
certify and get hybrids into the market place. BAE said that hybrids 
should not have to be tested on a chassis dynamometer.
    Given the options available for certification of hybrid systems, 
the constraints on available infrastructure for traditional chassis 
testing and coastdown testing has been mitigated. Should a manufacturer 
contemplate chassis testing or powerpack testing to assess hybrid 
vehicle performance, coastdown testing will still be needed for 
vocational applications to develop the road load values. To address 
concerns regarding the baseline vehicle definition, the following 
clarifications are provided. The baseline vehicle must be identical to 
the hybrid, with the exception being the presence of the hybrid 
vehicle. Should an identical vehicle not be available as a baseline, 
the baseline vehicle and hybrid vehicle must have equivalent power or 
the hybrid vehicle must have greater power. Additionally, the sales 
volume of the conventional vehicle from the previous model year (the 
vehicle being displaced by the hybrid), must be substantially such that 
there can be a reasonable basis to believe the hybrid certification and 
related improvement factor are authentic. Should no previous year 
baseline or otherwise existing baseline vehicle exist, the manufacturer 
shall produce or provide a prototype equivalent test vehicle. For pre-
transmission hybrid certification, drivetrain components will not be 
included in the testing, as is the case for criteria pollutant engine 
certification today on a brake-specific basis. Manufacturers are 
expected to submit A to B test results for the hybrid vehicle 
certification being sought for each vehicle family. Manufacturers may 
choose the worst case performer as a basis for the entire family. The 
agencies continue to expect to use existing precedent regarding 
treatment of accessory loads for purposes of chassis testing. Accessory 
loads for A to B testing will not need to be accounted for differently 
for hybrid A to B chassis testing than for criteria pollutant chassis 
testing. Based on the description of the hybrid engines and vehicles as 
found in

[[Page 57249]]

40 CFR 1036 and 1037.801, the agencies will not restrict hybrid 
configuration certification. The expectation is that hybrid engines and 
vehicles certified under the provisions for GHG will use certified 
engines. As stated previously, based on data provided by commenters and 
industry associations, the agencies have revised the duty cycles for 
complete vehicle and post-transmission powerpack testing by revising 
the weighting factors such that the performance of the hybrid system is 
more appropriately characterized. The new weighting factors result in a 
performance assessment that more closely matches performance seen in-
use by many of the applications most likely to be hybridized in the 
near-term. At this time the requirement to conduct coastdown testing 
remains in place for the vehicle to be chassis tested or for the 
simulated vehicle in powertrain testing. Absent appropriate 
coefficients that accurately reflect vehicle performance, making an 
assumption about vehicle performance could lead to erroneous results 
and/or errors in the performance assessment. The agencies have provided 
numerous flexibilities, so the options available to those manufacturers 
who choose to certify hybrid engines or vehicles are not constrained to 
a single test method for which limited infrastructure may exist.
(ii) Engine Dynamometer Evaluation
    The engine test procedure proposed in the NPRM for hybrid 
evaluation involved exercising the conventional engine and hybrid-
engine system based on an engine testing strategy. The basis for the 
system control volume, which serves to determine the valid test 
article, would need to be the most accurate representation of real 
world functionality. An engine test methodology would be considered 
valid to the extent the test is performed on a test article that does 
not mischaracterize criteria pollutant performance or actual system 
performance. Energy inputs should not be based on simulation data which 
is not an accurate reflection of actual real world operation. Pre-
transmission test protocols will include both the engine and the hybrid 
system for assessing GHG performance, however EPA is not changing 
criteria pollutant certification at this time for engines. In effect, 
the engine will need to be certified for criteria pollutant 
performance, while the engine and hybrid system in combination may be 
certified for GHG performance. It is clearly important to be sure 
credits are generated based on known physical systems. This includes 
testing using the appropriate recovered vehicle kinetic energy. 
Additionally, the duty cycle over which this engine-hybrid system would 
be exercised would need to reflect the use of the application, while 
not promoting a proliferation of duty cycles which prevent a 
standardized basis for comparing hybrid system performance. The 
agencies proposed the use of the Heavy-duty FTP cycle for evaluation of 
hybrid vehicles, which is the same test cycle final for engines 
installed in vocational vehicles. For powerpack testing, which includes 
the engine and hybrid systems in a pre-transmission format, the engine 
based testing is applicable for determination of brake-specific 
emissions benefit versus the engine standard. For post-transmission 
powertrain systems and vehicles, the comparison evaluation based on the 
Improvement Factor and the GEM result based on a vehicle drive trace in 
a powertrain test cell or chassis dynamometer test cell seem to 
accurately reflect the performance improvements associated with these 
test configurations. It is important that introduction of clean 
technology be incentivized without compromising the program intent of 
real world improvements in GHG and fuel consumption performance. In the 
NPRM the agencies asked for comments on the most appropriate test 
procedures to accurately reflect the performance improvement associated 
with hybrid systems tested using these or other protocols. 75 FR at 
74257.
    A number of comments were received on the proposed engine testing 
approaches. Comments were received from EMA/TMA, Cummins, Allison, 
Hino, and ICCT, stating that the hybrid test methodology needs to be 
more clearly defined. EMA/TMA, Cummins, and Allison stated that the 
agencies have not defined what they will accept as a ``complete hybrid 
system'' and a clearer definition for hybrids needs to be developed. 
For example, Allison stated that the DRIA says that a ``complete hybrid 
system'' can exclude the transmission. They added that a hybrid system 
must include a transmission. EMA/TMA stated that simulated engine 
dynamometer testing should include hybrid components. EMA/TMA stated 
that the agencies' proposal that part 1065 may be amended, but did not 
provide specifics on how it might be amended. They suggested the 
following changes to part 1065: (1) All engine and hybrid components 
capable of providing or recovering traction power be included in the 
control volume; (2) use of hybrid system torque curves rather than 
engine torque curves; (3) reference to J2711 for management of energy 
storage devices; (4) adhere to conventional calculation of emissions 
with only positive work counted; and (5) provide an estimate of maximum 
available kinetic energy in 1065 to ensure that energy capture is 
consistent with real world operation of hybrids.
    Hino said that energy recapture from regenerative braking needs to 
be built into the test cycle and as currently designed it is not. 
Regenerative braking provides fuel consumption and GHG reduction 
benefits. Eaton said that the proposed powerpack testing does not 
capture true performance of hybrid vehicles. As noted above, ICCT 
commented on the need for parity between engine and vehicle test 
cycles. They supported hardware-in-the-loop post-transmission testing, 
but only if an equivalent cycle is used as for chassis testing.
    Concerns were raised by hybrid system manufacturers that the 
potential for a competitive advantage could exist for hybrids using 
different methods for certification based solely on the test method 
chosen. For determination of the allowable brake energy that may be 
used for the test cycle with hybrid engines, it is important to provide 
consistency between test methods. For that reason EPA is setting a 
brake energy fraction limit based on the engine FTP duty cycle which 
would apply to the pre-transmission hybrid and defining that as the 
limit for the post-transmission maximum available brake energy as well. 
The brake energy fraction will need to be determined based on the 
engine performance and the brake energy fraction limit will apply for 
all powertrain test cell (powerpack) testing. This limit on the brake 
energy fraction will be ratio of negative work to positive work as a 
function of engine rated power.
    The agencies are also finalizing that the proposed duty cycles 
considered for the proposal will continue to be used with this final 
action. The agencies proposed a transient duty cycle, a 55-mile-per-
hour steady state cruise and a 65-mile-per-hour steady state cruise. 
The transient duty cycle, which has been corrected to address a concern 
related to shift events, is essentially the same transient cycle 
proposed in the NPRM with the exception that it minimizes inappropriate 
shift events. Additionally, the steady state cycles proposed by the 
Agencies remain essentially unchanged. The modification being adopted 
with today's final action is to address the distribution of the 
emissions impact associated with each duty cycle. However, in response 
to the concerns detailed above and

[[Page 57250]]

raised by engine manufacturers, hybrid system manufacturers, 
environmental groups, and NGOs regarding the lack of transient 
operation in the hybrid cycles, the agencies are finalizing a change in 
the weighting of the hybrid vehicle cycles. The weighting factors will 
be changed such that a greater emphasis on the type of transient 
activity seen as more characteristic of hybrid applications will be 
evident. The new weighting factors between duty cycles for hybrid 
certification (without PTO) will be 75 percent for the transient, 9 
percent for the 55 mph cruise cycle, and 16 percent for the 65 mph 
cruise cycle. The basis for this change may be seen in the memorandum 
to OAR Docket EPA-HQ-OAR-2010-0162 which describes the data set used to 
describe real world vehicle performance. Additionally, provisions for 
addressing brake energy fraction have been provided in 40 CFR 1036.525 
for hybrid engine testing. The control volume for testing hybrid 
systems for GHG and fuel consumption assessment has included all hybrid 
power systems and for powertrain testing that is post-transmission, 
simulated components including tires and regenerative braking impacts. 
Additionally, provisions for accounting for the hybrid system and 
engine torque curve are available in the hybrid test procedures of 40 
CFR 1036.525.
    In addition, the final rules allow manufacturers that want to 
certify a hybrid on a different test cycle than the cycles described 
above for chassis and engine dynamometer testing instead make a 
demonstration using the procedures set out in the Innovative Technology 
Credit provisions. Likewise, a manufacturer seeking to certify a hybrid 
using an alternative approach, such as simulation modeling, would need 
to follow the procedure described in the Innovative Technology Credit 
section. However, manufacturers whose alternative hybrid testing 
procedure is approved through the Innovative Technology Credit Program 
would receive credits through the Advanced Technology Credit Program so 
such credits would be fungible across all vehicle and engine categories 
and would receive the 1.5 multiplier.
    EMA/TMA also asked that in addition to the above-described engine, 
chassis, and powerpack testing, other yet-to-be-defined methods should 
be allowed so that a novel application of hybrids can be evaluated for 
credit. They included hydraulic, kinetic, electro-mechanical, and 
genset hybrids as examples of additional configurations that should be 
accommodated by additional test cycles. Allison asked how emissions and 
fuel consumption changes associated with ageing of hybrid systems will 
be accounted for. ACEEE encouraged the agencies to finalize the three 
approaches outlined in the NPRM for hybrid testing in the final rules.
    Cummins supported three proposed options for evaluating hybrids. 
ICCT supported option 1 and 3, but not 2. ICCT stated that EPA and 
NHTSA need to ensure that: (1) Each hybrid test method/test cycle 
combination requires the same amount of total energy to run the cycle 
(for a specific vehicle weight), (2) each test method/test cycle 
combination has the same amount of total energy available for capture 
as regeneration by a hybrid system, and (3) that this available 
regeneration energy appears in similar increments in each test method/
test cycle combination.
    In allowing for three options for certification of hybrids, two of 
those options require the use of a baseline vehicle. The post-
transmission hybrid certification and the chassis dynamometer 
certification options are designed to allow for an assessment of the 
improvement offered by incorporating a hybrid system into the vehicle. 
Determination of an improvement factor for hybrid vehicle performance 
is significantly influenced by the selection of the baseline vehicle, 
test article ``A''. The Agencies received comments from engine and 
hybrid system manufacturers that the options for selection of the 
baseline should be carefully considered to avoid an unintended 
consequence of limited real world improvement due to selection of a 
baseline that was inappropriate. Several concerns regarding an 
inappropriate baseline were broached including selection of technology 
that is not actually available in the market, selection of baseline 
technology that is not representative of the application(s) either by 
sales volume or use, or selection of a baseline that in other ways 
provides an advantage to a manufacturer which creates an unfair 
competitive advantage. To address the concern of improvement factors 
that have a basis in reality and demonstrate real world improvements, 
as well as to continue to create incentives for the introduction of new 
technology the Agencies are addressing the issue of the baseline 
selection, as well as the determination of a ``most similar'' vehicle 
basis in the case where there may not be an existing production vehicle 
upon which the hybrid vehicle was based.
    In making the determination of an appropriate baseline, four 
options were considered by the agencies. These options included a fixed 
baseline weight and definition by vehicle class, a non-hybrid baseline 
intended for production vehicle and transmission system, a best in 
class conventional application, or vehicle based on highest sales 
volume. Each of these options has benefits and each raises potential 
concerns. The determination based solely on a single vehicle by class 
has the advantage of providing a fixed baseline the entire industry may 
easily target for assessing improvements. It raises concerns regarding 
the suitability of the vehicle selection for all applications in the 
weight class, as well as the appropriateness of the selection based on 
performance across the full range of vehicles and weights in the weight 
class. The ``intended for production'' conventional vehicle baseline 
ensures the baseline and hybrid vehicle pair will represent a real 
improvement for the specific application. The challenge exists when the 
conventional vehicle version of the hybrid may not exist. Another issue 
would exist if the conventional vehicle in the pair had performance 
characteristics such that the hybrid version does not represent 
significant improvements beyond other conventional vehicles. The best 
in class baseline vehicle approach provides some assurance that the 
improvement factor generated by the hybrid vehicle or system would in 
fact represent introduction of advanced technology with improvements 
beyond existing conventional technology. The opportunity for confusion 
that exists with a best in class determination includes matching all of 
the appropriate performance metrics with the appropriate applications 
in a way that is consistent with how the market values those 
improvements. This can become a moving target which could represent an 
ever evolving design target and eventually prove difficult for the 
Agencies to implement in a way that ensured a level playing field. The 
last option attempts to include the benefits of the previous options, 
while maintaining the clarity needed for manufacturers to design and 
build with a clear understanding of design targets. The highest sales 
volume application by weight class for the previous model year ensures 
benefits are measured based on how the market values performance. This 
has the potential to avoid ambiguity regarding which vehicle technology 
should serve as the baseline and it addresses a concern raised by some 
commenters regarding the use of a baseline vehicle that clearly is not 
a class leader. The presumption being that the market will value the 
conventional technology that provides the best value over the lifetime 
of the vehicle for its

[[Page 57251]]

intended service class and application. This approach is intended to be 
used in conjunction with the basic premise that the ``A'' vehicle will 
be the vehicle most similar to the hybrid ``B'' vehicle.
    Should no apparent baseline be available, the vehicle being 
displaced by the hybrid may be determined based on several 
characteristics including but not limited to vehicle class, vehicle 
application, and complete power system rated power (e.g. engine rated 
power for the base vehicle versus combined rated power for the engine-
hybrid system). The agencies will continue to use the primary method of 
highest sales volume, by application and vehicle weight class in its 
assessment of the manufacturers selection of a baseline, however should 
there be a new application introduced with no apparent existing 
baseline, the closest baseline vehicle may be selected by the 
manufacturer and will be evaluated by the agencies.
    The commenters' concerns will continue to be reviewed by the 
agencies as the program is implemented; however, the approach suggested 
may not be appropriate across every method. To the extent that the pre-
transmission testing is a work based assessment consistent with today's 
engine testing, we are remaining consistent with current practices in 
which the engine certification has applicability across applications. 
With that said we have defined a regenerative brake limit that will 
align the relative energy (regenerative to tractive) across all three 
methods. This can be found in 40 CFR 1036.525.
    Given the use of the same duty cycles for both post-transmission 
and chassis dynamometer testing, we are capturing the performance of 
the powertrain by exercising it in the same manner for both methods, so 
the methods will be equivalent in all three aspects that were mentioned 
by the commenter.
(3) Innovative Technology Credits
    The agencies proposed a credit opportunity intended to apply to new 
and innovative technologies that reduce fuel consumption and 
CO2 emissions, but for which the reduction benefits are not 
captured over the test procedure, including the GEM, used to determine 
compliance with the standards (i.e., the benefits are ``off-cycle''). 
See 75 FR at 74257-58; see also 75 FR 25438-25440 where EPA adopted a 
similar credit program for MY 2012-2016 light-duty vehicles.
    The agencies explained in the NPRM that EPA and NHTSA are aware of 
some emerging and innovative technologies and concepts in various 
stages of development with CO2 emissions and fuel 
consumption reduction potential that might not be adequately captured 
on the final certification test cycles or are not inputs to the GEM, 
and that some of these technologies might merit some additional 
CO2 and fuel consumption credit generating potential for the 
manufacturer. Eligible innovative technologies are those technologies 
that are newly introduced in one or more vehicle models or engines, but 
that are not yet widely implemented in the heavy-duty fleet--and more 
specifically, not yet widely implemented in the averaging set for which 
the credit is sought. Examples of such technologies mentioned in the 
NPRM include predictive cruise control, gear-down protection, active 
aerodynamic features, and adjustable ride height. Innovative 
technologies can include known, commercialized technologies if they are 
not yet widely utilized in a particular heavy-duty sector subcategory. 
Any credits for these technologies would need to be based on real-world 
fuel consumption and GHG reductions that can be measured with 
verifiable test methods using representative driving conditions typical 
of the engine or vehicle application.
    In the NPRM, the agencies stated that we would not consider 
technologies to be eligible for these credits if the technology has a 
significant impact on CO2 emissions and fuel consumption 
over the primary test cycles, or if it is one of the technologies on 
whose performance the various vehicle and engine standards are 
premised. The agencies believe it is appropriate to provide an 
incentive to encourage the introduction of these types of technologies 
and that a credit mechanism is an effective way to do so. Further, 
there needs to be a mechanism to account for the emission reductions 
and fuel efficiencies resulting when an innovative technology is used. 
The agencies proposed that this optional credit opportunity would be 
available through the 2018 model year reflecting that technologies 
which are now uncommon may be more widely utilized by then, but the 
agencies sought comment on the need to extend the ability to earn 
credits beyond the model year 2018. See generally 75 FR at 74257-258.
    EPA and NHTSA also proposed that credits generated using innovative 
technologies be restricted within the subcategory averaging set where 
the credit was generated but requested comments on whether these 
innovative technology credits should be fungible across vehicle and 
engine categories.
    The agencies also proposed that manufacturers quantify 
CO2 and fuel consumption reductions associated with the use 
of the off-cycle technologies such that the credits could be applied 
based on the metrics (such as g/mile and gal/100 mile for pickup 
trucks, g/ton-mile and gal/1,000 ton-mile for tractors and vocational 
vehicles, and g/bhp-hr and gal/100 bhp-hr for engines). Credits would 
have to be based on real additional reductions of CO2 
emissions and fuel consumption and would need to be quantifiable and 
verifiable with a repeatable methodology. Such data would be submitted 
to EPA and NHTSA, and would be subject to a public evaluation process 
in which the public would have opportunity for comment. See 75 FR at 
74258. We proposed that the technologies upon which the credits are 
based would be subject to full useful life compliance provisions, as 
with other emissions controls. Unless the manufacturer can demonstrate 
that the technology would not be subject to in-use deterioration over 
the useful life of the vehicle, the manufacturer would have to account 
for deterioration in the estimation of the credits in order to ensure 
that the credits are based on real in-use emissions reductions over the 
life of the vehicle.
    In cases where the benefit of a technological approach to reducing 
CO2 emissions and fuel consumption cannot be adequately 
represented using existing test cycles, it was proposed that EPA and 
NHTSA would review and approve as appropriate test procedures and 
analytical approaches to estimate the effectiveness of the technology 
for the purpose of generating credits. The demonstration program would 
have to be robust, verifiable, and capable of demonstrating the real-
world emissions benefit of the technology with strong statistical 
significance.
    Finally, the agencies explained in the NPRM that the CO2 
and fuel consumption benefit of some technologies may have to be 
demonstrated with a modeling approach. In other cases manufacturers 
might have to design on-road test programs that are statistically 
robust and based on real world driving conditions. As with the similar 
procedure for alternative off-cycle credits under the light-duty 2012-
2016 MY vehicle program, the agencies would include an opportunity for 
public comment as part of any approval process.
    The agencies requested comments on the proposed approach for off-
cycle innovative technology emissions credits, including comments on 
how

[[Page 57252]]

best to structure the program. EPA and NHTSA particularly requested 
comments on how the case-by-case approach to assessing off-cycle 
innovative technology credits could best be designed, including ways to 
ensure the verification of real-world emissions benefits and to ensure 
transparency in the process of reviewing manufacturer's proposed test 
methods.
    The agencies received numerous comments relating to all aspects of 
the innovative technology credit flexibility provision. The vast 
majority of the commenters supported this provision as proposed, but 
requested that certain aspects be further clarified, so the agencies 
are adopting the full provision as proposed and providing further 
discussion that addresses and clarifies the provision in response to 
comments. We also note generally that many comments asserting that the 
GEM or certain of the engine standards failed to account for certain 
types of emission reductions associated with technology improvements 
did not consider the availability of innovative technologies for such 
technologies. These comments are addressed specifically in the Response 
to Comment Document or elsewhere in this preamble.
    A number of organizations, including DTNA, MEMA, Navistar, Green 
Truck Association, Eaton, ACEEE, and NESCAUM, commented that 
technologies such as advanced transmissions, engine cooling strategies, 
idle reduction, light-weight components (including light-weight 
engines), and advanced drivelines should be able to receive credit 
through the innovative technology program. The agencies agree with 
these commenters. The NPRM did not provide a specific list of 
technologies that the agencies would consider ``innovative'' because 
the agencies intended that an innovative technology could be any 
technology not in widespread use in the subcategory that can be proven 
to reduce CO2 emissions and fuel consumption but for which 
the benefits are not captured utilizing the FTP procedures, SET 
procedures and GEM methodology used to determine compliance with the 
emission and fuel consumption standards. Any of the suggested 
technologies could be considered as an innovative technology if the 
associated emission and fuel consumption benefit has not already been 
considered to have widespread use in the subcategory, if the associated 
emission and fuel savings can be measured and validated, and if the 
technology and measurement methodology have been approved by the 
agencies. NHTSA and EPA will determine the impact of the technology and 
each agency in turn will accept the credits either jointly or 
independently depending upon whether the technology has a direct 
bearing upon GHG or fuel consumption performance.
    A number of commenters, including Bendix, Bosch, Cummins, EMA/TMA, 
Eaton, DTNA, Navistar, Volvo, ArvinMeritor and USC requested that the 
innovative technology process and procedures be more clearly structured 
and defined. Bendix requested that the agencies prescribe specific 
processes and procedures in the final rules by which innovative 
technologies can be submitted for review and approval. EMA/TMA 
requested that the agencies provide guidance on the certification 
process, and suggested that existing fuel consumption test procedures 
developed jointly by the Society of Automotive Engineers (SAE) and the 
Technology & Maintenance Council (TMC), specifically that the Type II 
and Type III procedures be used. Eaton requested that the agencies 
identify test methods that can be used for certification in order to 
provide transparency and certainty, and promote early technology 
introduction. In response to these comments, the agencies have further 
defined the process in the final action.
    In cases where the benefit of a technological approach to reducing 
CO2 emissions and fuel consumption cannot be adequately 
represented using existing test cycles, EPA and NHTSA will review and 
approve test procedures and analytical approaches as appropriate to 
estimate the effectiveness of the technology for the purpose of 
generating credits. The innovative technologies will be evaluated in an 
A-to-B comparison. The baseline engine and/or vehicle configuration 
must represent a configuration which is equivalent to the engine and/or 
vehicle with the innovative technology in terms of the other aspects of 
the engine and/or vehicle to prevent double counting of emissions 
reductions or gaming.
    Since innovative credits will be available for use within the same 
averaging set as the engine or vehicle which employs the innovative 
technology (for reasons explained below), the agencies are defining 
innovative credit approaches by regulatory category.
(a) Heavy-Duty Pickup Truck and Van Innovative Technology Credits
    For HD pickups and vans, EPA and NHTSA proposed that they would 
review and approve manufacturer-provided test procedures and analytical 
approaches to estimate the effectiveness of a technology for the 
purpose of generating credits. The proposal also expressed the view 
that the 5-cycle approach currently used in EPA's fuel economy labeling 
program for light-duty vehicles may provide a suitable test regime, 
provided it can be reliably conducted on the dynamometer and can 
capture the impact of the off-cycle technology (see 71 FR 77872, 
December 27, 2006). EPA established the 5-cycle test methods to better 
represent real-world factors impacting fuel economy, including higher 
speeds and more aggressive driving, colder temperature operation, and 
the use of air conditioning. Because we have not firmly established the 
suitability of the 5-cycle approach for HD pickups and vans at this 
time, and we received no comments or data helping to establish it, we 
are not adopting provisions to specify its use. However, it remains a 
candidate approach that manufacturers may pursue in making their 
demonstrations for innovative technology credits, described below.
    Manufacturer data submitted to the agencies in pursuit of 
innovative technology credits would be subject to a public evaluation 
process in which the public would have opportunity for comment.\301\ 
Whether the approach involves on-road testing, modeling, or some other 
analytical approach, the manufacturer would be required to present a 
final methodology to EPA and NHTSA. EPA and NHTSA would approve the 
methodology and credits only if certain criteria were met. Baseline 
emissions and fuel consumption \302\ and control emissions and fuel 
consumption would need to be clearly demonstrated over a wide range of 
real world driving conditions and over a sufficient number of vehicles 
to address issues of uncertainty with the data. Data would need to be 
on a vehicle model-specific basis unless a manufacturer demonstrated 
model-specific data was not necessary. The agencies would publish a 
notice of availability in the Federal Register notifying the public of 
a manufacturer's proposed alternative off-cycle credit calculation 
methodology and provide opportunity for comment. The notice will 
include details regarding the methodology, but not include any 
Confidential Business Information.
---------------------------------------------------------------------------

    \301\ See 75 FR 25440.
    \302\ Fuel consumption is derived from measured CO2 
emissions using conversion factors of 8,887 g CO2/gallon 
for gasoline and 10,180 g CO2/gallon for diesel fuel.
---------------------------------------------------------------------------

    The agencies did not receive any adverse comments on using the 
proposed approach for HD pickup trucks and vans. Consistent with the 
proposal, the agencies are adopting the

[[Page 57253]]

proposed innovative technology credit provisions for HD pickup trucks 
and vans.
(b) Heavy-Duty Engine, Combination Tractor, and Vocational Vehicle 
Innovative Technology Credits
    Innovative technology credits developed in the HD engine, 
combination tractor, and vocational vehicle categories will need to be 
applied to the subcategory in which they were generated. The agencies 
are adopting provisions in Sec.  1037.610 to determine the separation 
of engine credits and vehicle credits based on the method which is 
selected by the manufacturer to determine the effectiveness of the 
innovative technology. For example, improvements to the engine that are 
demonstrated in either the engine dynamometer test or powerpack test 
will clearly be engine credits. Improvements that are demonstrated 
using chassis dynamometer or on-road test will be considered vehicle 
credits. However, the agencies recognize that there may be exceptions 
to this approach, and will allow for the manufacturer to request an 
alternate classification of credits. A change in credit allocation will 
require approval from the agencies and would be subject to a public 
evaluation process.
    Furthermore, to address the concerns of some commenters mentioned 
above, the agencies are adopting an approach for HD engines and 
vehicles that provides two paths for approval of the test procedure to 
measure the CO2 emissions and fuel consumption reductions of 
an innovative off-cycle technology used in the HD engine or vehicle. 
These alternative approaches are similar to those adopted in the light-
duty vehicle rule. The first path will not require a public approval 
process of the test method. The ``pre-approved'' test methods for HD 
engines and vehicles will include the A-to-B chassis testing, powerpack 
testing, and on-road testing. The agencies are also adopting as 
proposed a second test method approval path that provides a 
manufacturer the ability to submit an alternative evaluation approach 
to EPA and NHTSA, which must be approved by the agencies prior to the 
demonstration program. As with HD pickup trucks and vans, such 
submissions of data should be submitted to the agencies and would be 
subject to a public evaluation process in which the public would have 
opportunity for comment.\303\ Baseline emissions and control emissions 
would need to be clearly demonstrated over a wide range of real world 
driving conditions and over a sufficient number of vehicles to address 
issues of uncertainty with the data. The agencies will publish a notice 
of availability in the Federal Register notifying the public of a 
manufacturer's proposed alternative off-cycle credit calculation 
methodology and provide opportunity for comment. The notice will 
include details regarding the methodology, but not include any 
Confidential Business Information. Approval of the approach to 
determining a CO2 and fuel consumption benefit would not 
imply approval of the results of the program or methodology; when the 
testing, modeling, or analyses are complete the results would likewise 
be subject to EPA and NHTSA review and approval.
---------------------------------------------------------------------------

    \303\ See 75 FR 25440.
---------------------------------------------------------------------------

    The pre-approved test procedures include engine dynamometer, 
powerpack, chassis dynamometer, and on-road testing. Each of the test 
procedures require the evaluation of a baseline and control engine or 
vehicle (A vs. B testing) to quantify the improvement. Manufacturers 
may use the engine dynamometer test procedures using the HD engine FTP 
or SET cycle. The chassis testing and powerpack testing would be 
conducted the same as described above for HD vocational vehicle and 
tractor hybrid testing in Section IV.B.2.b using the drive cycles and 
weightings finalized in this action for the primary program. If a 
manufacturer requires the use of an alternate duty cycle, then it will 
require prior approval from the agencies.
    The on-road testing would be tested according to SAE J1321 Joint 
TMC/SAE Fuel Consumption Test Procedure Type II Reaffirmed 1986-10 or 
SAE J1526 Joint TMC/SAE Fuel Consumption In-Service Test Procedure Type 
III Issues 1987-06, with additional constraints to improve the test 
repeatability. The first constraint requires that the minimum route 
distance be set at 100 miles. In addition, the route selected must be 
representative in terms of grade. The agencies will take into account 
published and relevant research in determining whether the grade is 
representative.\304\ Similarly, the speed of the route must be 
representative of the drive cycle weighting adopted for each regulatory 
subcategory. For example, if the route selected for an evaluation of a 
combination tractor with a sleeper cab contains only interstate 
driving, then the improvement factor would only apply to 86 percent of 
the weighted result. Lastly, the ambient air temperature must be 
between 5 and 35 [deg]C. The agencies also would allow the use of a 
Portable Emissions Measurement (PEMS) device for the measurement of 
CO2 emissions during the on-road testing. The agencies are 
not pre-approving any routes for the on-road testing. Manufacturers 
will be required to submit the proposed route prior to testing for 
approval.
---------------------------------------------------------------------------

    \304\ The agencies would consider information such as the study 
conducted by Oak Ridge National Lab which found that 72 percent of 
their data records were driven on flat terrain of less than 1 
percent grade to determine the representativeness of the route. See 
Capps, G., O. Franzes, B. Knee, M.B. Lascurain, and P. Otaduy. Class 
8 Heavy Truck Duty Cycle Project Final Report. ORNL/TM-2008/122, Oak 
Ridge National Laboratory. Last accessed on April 14, 2011 at page 
5-14 of http://cta.ornl.gov/data/tedb29/Edition29_Chapter05.pdf.
---------------------------------------------------------------------------

    The agencies requested comments on whether credits generated using 
innovative technologies should be fungible across vehicle and engine 
categories and received comments both supporting and opposing the 
limited fungibility of these credits. Cummins did not support the 
fungibility of innovative technology credits across subcategories, 
arguing that it is not advisable given the large number and variability 
of different technology types and the uncertainty in this provision. 
DTNA stated that the credits should be fungible across engine and 
vehicle classes to be treated the same as advanced technology credits. 
EPA and NHTSA acknowledge that the HD program is a new program and, 
though the agencies continue to believe the credit provision is an 
important flexibility, the agencies are implementing innovative 
technology credits based on the ability to assign a value for future 
technologies and test methods that are as yet to be defined. Given the 
fact that the agencies cannot make a determination at this time of, 
what innovative technologies will be offered, and thus the impact of 
increased fungibility to sectors outside the original application of 
the innovative technology might be, it is premature to allow that 
credit to be traded without restriction and with additional credit. 
Until such uncertainty can be understood and quantified, the agencies 
believe the final rules should continue to include restrictions on the 
fungibility of innovative technology credits across service classes and 
categories.
    The agencies proposed that this credit opportunity be available 
through the 2018 model year, reflecting that technologies may be common 
by then, but sought comment on the need to extend beyond model year 
2018. The agencies received comments from DTNA, Navistar, Eaton, 
Cummins and Bosch supporting the extension of this provision beyond 
model year 2018. Eaton stated that though some

[[Page 57254]]

technologies will be more common in 2018, new technologies will evolve 
facing the same difficulties concerning implementation and would 
benefit from this provision. Bosch explained that extension of the 
provision past 2018 is important because at the time of the final rule 
the GEM will not incorporate any newer technology until it is updated 
in phase two of the program, and manufacturers will therefore continue 
to need the innovative technology provision for receiving credits for 
technologies not accounted for in GEM. The agencies have reviewed these 
concerns and believe that they are valid. Therefore, the final rule 
does not state that this provision ends in model year 2018. Any action 
taken on these credits in a subsequent rulemaking will be addressed by 
the agencies at that time in that future rulemaking.
(4) N2O Credit
    EPA received a comment from an industry stakeholder requesting a 
provision to allow manufacturers of heavy-duty engines to gain credit 
for redesigning emission control systems to reduce N2O 
emissions. The commenter argued that unlike CH4, 
N2O emissions from some NOX control technologies 
can vary in inverse proportion to CO2 emissions. Given such 
a tradeoff, it would be appropriate to allow manufacturers to exploit 
that tradeoff to achieve the lowest overall greenhouse gas emissions 
possible. Thus, EPA is adopting a provision which allows engine 
manufacturers to generate CO2 credits for very low 
N2O emissions. Specifically, manufacturers that certify 
engines with full useful life N2O FEL emissions which are 
less than 0.04 g/hp-hr could generate 2.98 grams of CO2 
credit for 0.01 grams of N2O reduced (consistent with the 
relative global warming potentials of CO2 and 
N2O). For example, where a manufacturer certifies an engine 
family to have low per-brake horsepower hour N2O emissions 
of 0.01 g/hp-hr and applies the 0.02 g/hp-hr assigned deterioration 
factor, it could certify the engine family to a 0.03 g/hp-hr 
N2O FEL and generate enough CO2 credits to offset 
CO2 emissions 2.98 g/hp-hr above the standard. The 0.04 g/
hp-hr level is less than the cap standard of 0.10 g/bhp-hr (so credits 
generated would not be windfalls) and reflects EPA's best estimate of 
average N2O performance for today's engine technologies. See 
Table II-22 above. This value has been chosen to ensure the credit 
reflects improvements beyond today's baseline performance level. EPA is 
limiting this provision to model years 2014 through 2016, the same 
years that NHTSA's program is voluntary, to maintain alignment between 
the CO2 emissions and fuel consumption standards. EPA 
considered allowing the provision to continue beyond 2016 but decided 
given its relatively small value (we expect this credit to be worth 
approximately 3 g/bhp-hr on a standard of 460 g/bhp-hr) and the 
ultimate desirability of alignment of the EPA and NHTSA programs to 
limit the period of this flexibility to the period of time when the 
NHTSA program will be voluntary.

V. NHTSA and EPA Compliance, Certification, and Enforcement Provisions

A. Overview

(1) Compliance Approach
    This section describes EPA's and NHTSA's final program to ensure 
compliance with EPA's final emission standards for CO2, 
N2O, and CH4 and NHTSA's final fuel consumption 
standards, as described in Section II. To achieve the goals projected 
in the proposal, it is important for the agencies to have an effective 
and coordinated compliance program for our respective standards. As is 
the case with the light-duty vehicle rule, the final compliance program 
for heavy-duty vehicles and engines has two central priorities: (1) To 
address the agencies' respective statutory requirements; and (2) to 
streamline the compliance process for both manufacturers and the 
agencies by building on existing practice wherever possible, and by 
structuring the program such that manufacturers can use a single data 
set to satisfy the requirements of both agencies. It is also important 
to consider the provisions of EPA's existing criteria pollutant program 
and NHTSA's existing LD program in the development of the approach used 
for heavy-duty certification and compliance. The existing EPA heavy-
duty highway engine emissions program has an established infrastructure 
and methodology that will allow for an effective integration with this 
final GHG and fuel consumption program, without needing to create new 
unique processes in many instances. The HD compliance program will 
address the importance of the impact of new control methods for heavy-
duty vehicles as well as other control systems and strategies that may 
extend beyond the traditional purview of the criteria pollutant 
program.
    Section 202(b)(3)(A) of the Clean Air Act (CAA) defines ``model 
year'' to mean ``* * * the manufacturer's annual production period (as 
determined by the Administrator) which includes January 1 of such 
calendar year'' or to mean calendar year if the manufacturer has no 
annual production period. Section 32901(a)(16) of EISA defines ``model 
year'' with almost identical language. Section 202(b)(3)(A) of the CAA 
also allows the EPA Administrator to define model year differently to 
assure `` * * * that vehicles and engines manufactured before the 
beginning of a model year were not manufactured for purposes of 
circumventing the effective date of a standard * * *.'' Consistent with 
this statutory language, the NPRM proposed regulatory text to define 
``model year,'' in 40 CFR 1036.801, 40 CFR 1037.801 and 49 CFR 535.4. 
All three codified the primary CAA and EISA definition, but differed 
with respect to language intended to prevent circumvention of the 
standards. The proposed definition for engines was in the proposed rule 
published November 30, 2010, 75 FR 74377, which stated that ``model 
year'' means the manufacturer's annual new model production period, 
except as restricted under this definition. It must include January 1 
of the calendar year for which the model year is named, may not begin 
before January 2 of the previous calendar year, and it must end by 
December 31 of the named calendar year. Manufacturers may not adjust 
model years to circumvent or delay compliance with emission or 
standards or to avoid the obligation to certify annually.
    The proposed definition for vehicles was in the proposed rule 
published November 30, 2010, 75 FR 74401, which stated that ``model 
year'' means the manufacturer's annual new model production period, 
except as restricted under this definition and 40 CFR part 85, subpart 
X. It must include January 1 of the calendar year for which the model 
year is named, may not begin before January 2 of the previous calendar 
year, and it must end by December 31 of the named calendar year. Use 
the date on which a vehicle is shipped from the factory in which you 
finish your assembly process as the date of manufacture for determining 
your model year. For example, where a certificate holder sells a cab-
complete vehicle to a secondary vehicle manufacturer, the model year is 
based on the date the vehicle leaves the factory as a cab-complete 
vehicle.
    EPA's and NHTSA's vehicle model year definitions differed slightly 
in wording but were essentially the same for Sec. Sec.  1037.801 and 
535.4. In creating the model year definition for vehicles, the agencies 
were mindful of the confusion chassis manufacturers may face in 
determining their model years in a given period of production, for 
example, due to manufacturing and

[[Page 57255]]

shipping products at different levels of completion and involving 
multiple manufacturers. The agencies included the term ``ship date'' in 
order to provide chassis manufacturers a clear reference date (``in 
which you finish your assembly process''), as well as to decrease the 
risk of gaming that might occur if no reference date was specified and 
there were therefore no parameters on the choice of model year. The 
engine definition was chosen based on consistency with prior EPA 
definitions for other mobile source programs.
    The agencies received comments on the definitions from EMA/TMA and 
Navistar expressing concern over the potential for unintended 
consequences. The commenters argued that the use of ``ship date'' for 
vehicles could create difficulty and uncertainty for manufacturers for 
whom the ship date can be delayed for reasons outside of their control, 
such as late-arriving components. They also argued that the differences 
between the vehicle and engine definitions would increase the 
likelihood that a single vehicle would be subject to different fuel 
efficiency requirements during certain years of transition in the 
standards, as it would not be unlikely that a vehicle would be a later 
model year than an engine. For example, during the 2016-2017 period, an 
engine may be model year 2016 while the vehicle is model year 2017.
    NHTSA and EPA have considered further whether there are benefits to 
maintaining separate definitions for ``model year'' for the engine and 
vehicle standards based on these comments. We continue to believe that 
differences in manufacturing practices for engines and vehicles support 
the use of separate definitions. However, for this final action, we 
have decided to modify the definitions to account for the above 
concerns, address circumstances of multiple manufacturers, and provide 
increased consistency and clarity. Thus, instead of ``ship date,'' the 
vehicle definition for model year will refer to the date when the 
certifying manufacturer's ``manufacturing operations were completed,'' 
within the specified year. The final definition also specifies that 
each vehicle must be assigned a model year before introduction into 
U.S. commerce, but allow a manufacturer to redesignate a later model 
year if it does not complete its manufacturing operations for the 
vehicle within the initial model year.
    To further standardize with EPA definitions, NHTSA will add the EPA 
engine model year definition to its corresponding regulation 49 CFR 
535.4. We believe that this will address the concerns raised by 
commenters because it will provide standardization, more specificity 
and account for current manufacturer practices.
    The agencies are aware that the designation of a model year on a 
chassis for the purposes of this heavy-duty truck emission and fuel 
consumption program may result in a complete vehicle that has one model 
year associated with its chassis for emission/fuel consumption purposes 
and another model year designation in its vehicle identification number 
(VIN) for a motor vehicle's certification to Federal motor vehicle 
safety standards. However, as the chassis model year designation would 
only be used on the certificate of conformity by the responsible 
manufacturer for the purpose of complying with these rules, it would 
not contradict other purposes for which a VIN model year may be used.
    EMA/TMA also argued that the proposed dates used to specify the 
model year would shorten the lead time provided for manufacturers, 
because production for HD vehicles often begins in the early months of 
the year preceding the model year. We are addressing these concerns by 
finalizing January 1, 2014 as the date certain when manufacturers are 
required to comply. Prior to this date, certification of the vehicle 
would be optional. Thus, a manufacturer could produce uncertified model 
year 2014 vehicles through December 31, 2013. The heavy-duty compliance 
program uses a variety of mechanisms to conduct compliance assessments, 
including preproduction certification and postproduction testing and 
in-use monitoring once vehicles enter customer service. Specifically, 
the agencies are establishing a compliance program that utilizes 
existing EPA testing protocols and certification procedures. Under the 
provisions of this program, manufacturers will have significant 
opportunity to exercise implementation flexibility, based on the 
program schedule and design, as well as the credit provisions in the 
program for advanced technologies. This program includes a process to 
foster the use of innovative technologies, not yet contemplated in the 
current certification process. EPA and NHTSA will conduct compliance 
preview meetings which provide the agencies an opportunity to review a 
manufacturer's new product plans and ABT projections. Given the nature 
of the final compliance program that involves both engine and vehicle 
compliance for some categories, it is necessary for manufacturers to 
begin pre-certification meetings with the agencies early enough to 
address issues of certification and compliance for both integrated and 
non-integrated product offerings.
    Based on feedback EPA and NHTSA received during the light-duty GHG 
comment period, both agencies are seeking to ensure transparency in the 
compliance process of this program. In addition to providing 
information in published reports annually regarding the status of 
credit balances and compliance on an industry basis, EPA and NHTSA 
sought comments in the NPRM on additional strategies for providing 
information useful to the public regarding industry's progress toward 
reducing GHG emissions and fuel consumption from this sector while 
protecting sensitive business information. In response, commenters 
(Sierra Club and UCS) also had strong interests for the agencies to 
ensure that any collected data is made available to the public with an 
interest especially for providing details on the credit balances for 
each manufacturer and for data on specific vehicle configuration 
information data to better understand the market and help with the 
development of future programs. Additional requests (ALA and EDF) were 
also made for the agencies to expand consumer education and outreach 
for medium- and heavy-duty vehicles thereby empowering fleet purchasers 
to make better informed choices. Another commenter (ACEEE) specifically 
requested that the agencies publish a heavy-duty truck trend report 
describing vehicles and engines sold, including fuel efficiency and GHG 
performance and the use of advanced technology. It was further 
recommended (by ALA and EDF) that the agencies should create consumer 
education and outreach programs for medium and heavy-duty vehicles such 
as fuel consumption and GHG emissions information for all vehicles and 
engines covered by the rules, in buyers guide similar to the fuel 
economy guides that EPA and NHTSA provide for the light-duty CAFE 
program. ICCT and UCS also requested having a consumer based label for 
heavy-duty pickup trucks and vans providing fuel economy and emission 
information like in the light-duty CAFE program.
    The agencies agree that there is a need for sharing heavy-duty 
emissions and fuel consumption information and therefore will make 
information publically available under this program.
(a) Heavy-Duty Pickup Trucks and Vans
    The final compliance regulations (for certification, testing, 
reporting, and associated compliance activities) for heavy-duty pickup 
trucks and vans closely track both current practices and

[[Page 57256]]

the recently adopted greenhouse gas regulations for light-duty vehicles 
and trucks. Thus they are familiar to manufacturers. EPA already 
oversees testing, collects and processes test data, and performs 
calculations to determine compliance with both CAFE and CAA standards 
for Light-Duty. For Heavy-Duty products that closely parallel light-
duty pickups and vans, under a coordinated approach, the compliance 
mechanisms for both programs for NHTSA and EPA would be consistent and 
non-duplicative for GHG pollutant standards and fuel consumption 
requirements. Vehicle emission standards established under the CAA 
apply throughout a vehicle's full useful life.
    Under EPA's existing criteria pollutant emission standard program 
for heavy-duty pickup trucks and vans, vehicle manufacturers certify a 
group of vehicles called a test group. A test group typically includes 
multiple vehicle lines and model types that share critical emissions-
related features. The manufacturer generally selects and tests a single 
vehicle, typically considered ``worst case'' for criteria pollutant 
emissions, which is allowed to represent the entire test group for 
certification purposes. The test vehicle is the one expected to be the 
worst case for the emission standard at issue. Emissions from the test 
vehicle are assigned as the value for the entire test group. However, 
the compliance program in the recent GHG regulations for light-duty 
vehicles, which is essentially the well-established CAFE compliance 
program, allows and may require manufacturers to perform additional 
testing at finer levels of vehicle models and configurations in order 
to get more precise model-level fuel economy and CO2 
emission levels. The agencies are adopting this same approach for 
heavy-duty pickups and vans. Additionally, like the light-duty 
program's use of analytically derived fuel economy (ADFE) data, we will 
allow manufacturers to predict CO2 levels (and corresponding 
fuel consumption) of some vehicles in lieu of testing, using a 
methodology deemed appropriate by the agencies. Based on manufacturer 
input, a method for calculating analytically derived carbon dioxide 
(ADCO2) is specified in Sec.  1037.104 of this rule.\305\ At 
a manufacturer's request, EPA may approve analytical methods alternate 
to the method described in this rule if said alternate methods are 
deemed to be more accurate than the analytical method described in this 
rule.
---------------------------------------------------------------------------

    \305\ Memorandum from Don Kopinski, U.S. EPA to docket EPA-HQ-
OAR-2010-0162, July 7, 2011.
---------------------------------------------------------------------------

(b) Heavy-Duty Engines
    Heavy-duty engine certification and compliance for traditional 
criteria pollutants has been established by EPA in its current general 
form since 1985. In developing a program to address GHG pollutants, it 
is important to build upon the infrastructure for certification and 
compliance that exists today. At the same time, it is necessary to 
develop additional tools to address compliance with GHG emissions 
requirements, since the final standard reflect control strategies that 
extend beyond those of traditional criteria pollutants. In so doing, 
the agencies are finalizing use of EPA's current engine test based 
strategy--currently used for criteria pollutant compliance--to also 
measure compliance for GHG emissions. The agencies are also finalizing 
to add new strategies to address vehicle specific designs and hardware 
which impact GHG emissions. The traditional engine approach would 
largely match the existing criteria pollutant control strategy. This 
would allow the basic tools for certification and compliance, which 
have already been developed and implemented, to be expanded for carbon 
dioxide, methane, and nitrous oxide. Engines with similar emissions 
control technology may be certified in engine families, as with 
criteria pollutants.
    For EPA, the final approach for certification will follow the 
current process, which requires manufacturer submission of 
certification applications, approval of the application, and receipt of 
the certificate of conformity prior to introduction into commerce of 
any engines. EPA proposed the certificate of conformity be a single 
document that would be applicable for both criteria pollutants and 
greenhouse gas pollutants. For NHTSA, a manufacturer must submit 
certification applications with equivalent fuel consumption 
information. NHTSA will assess compliance with its fuel consumption 
standards based on the results of the EPA GHG emissions compliance 
process for each engine family.
(c) Class 7 and 8 Combination Tractors and Class 2b-8 Vocational 
Vehicles
    Currently, except for HD pickups and vans, EPA does not directly 
regulate exhaust emissions from heavy-duty vehicles as a complete 
entity. Instead, a compliance assessment of the engine is undertaken as 
described above. Vehicle manufacturers installing certified engines are 
required to do so in a manner that maintains all functionality of the 
emission control system. While no process exists for certifying these 
heavy-duty vehicles, the agencies believe that a process similar to the 
one we proposed to use for heavy-duty engines can be applied to the 
vehicles.
    The agencies are finalizing related certification programs for 
heavy-duty vehicles. Manufacturers will divide their vehicles into 
families and submit applications to each agency for certification for 
each family. However, the demonstration of compliance will not require 
emission testing of the complete vehicle, but will instead involve a 
computer simulation model, GEM. This modeling tool uses a combination 
of manufacturer-specified and agency-defined vehicle parameters to 
estimate vehicle emissions and fuel consumption. This model is then 
exercised over certain drive cycles. EPA and NHTSA are finalizing the 
duty cycles over which Class 7 and 8 combination tractors would be 
exercised to be: 65 mile per hour steady state cruise cycle, the 55 
mile per hour steady state cruise cycle, and the California ARB 
transient cycle. Additional details regarding these duty cycles will be 
addressed in Section V.D(1)(b) below. Over each duty cycle, the 
simulation tool will return the expected CO2 emissions, in 
g/ton-mile, and fuel consumption, gal/1,000 ton-mile, which would then 
be compared to the standards.

B. Heavy-Duty Pickup Trucks and Vans

 (i) Compliance Approach
    EPA and NHTSA are finalizing, largely as proposed, new emission 
standards to control greenhouse gases (GHGs) and reduce fuel 
consumption from heavy-duty vehicles with gross vehicle weight rating 
between 8,500 and 14,000 pounds that are not already covered under the 
MY 2012-2016 medium-duty passenger vehicle standards. In this section 
``trucks'' refers to heavy-duty pickup trucks and vans between 8,500 
and 14,000 pounds not already covered under the light-duty rule.
    First, EPA is finalizing fleet average emission standards for 
CO2 on a gram per mile (g/mile) basis and NHTSA is 
finalizing fuel consumption standards on a gal/100 mile basis that 
would apply to a manufacturer's fleet of heavy-duty trucks and vans 
with a GVWR from 8,500 pounds to14,000 pounds (Class 2b and 3). 
CO2 is the primary pollutant resulting from the combustion 
of vehicular fuels, and the amount of CO2 emitted is highly 
correlated to the amount of fuel consumed. In addition, the EPA is 
finalizing separate emissions standards for three other GHG

[[Page 57257]]

pollutants: CH4, N2O, and HFC. CH4 and 
N2O emissions relate closely to the design and efficient use 
of emission control hardware (i.e., catalytic converters). The 
standards for CH4 and N2O would be set as caps 
that would limit emissions increases and prevent backsliding from 
current emission levels. In lieu of meeting the caps, EPA is allowing 
manufacturers the option of offsetting any N2O emissions or 
any CH4 emissions above the cap by taking steps to further 
reduce CO2. Separately, EPA is finalizing to set standards 
to control the leakage of HFCs from air conditioning systems.
    Previously, complete vehicles with a Gross Vehicle Weight Rating of 
8,500-14,000 pounds could be certified according to 40 CFR part 86, 
subpart S. These heavy-duty chassis certified vehicles were required to 
pass emissions on both the Light-duty FTP and HFET (California 
requirement).\306\ These rules will use the same testing procedures 
already required for heavy-duty chassis certification, namely the 
Light-duty FTP and the HFET. Using the data from these two tests, EPA 
and NHTSA will compare the CO2 emissions and fuel 
consumption results against the attribute-based target. The attribute 
upon which the CO2 standard is based is a function of 
vehicle payload, vehicle towing capacity and two-wheel versus four-
wheel drive configuration. The attribute-based standard targets will be 
used to determine a manufacturer fleet standard. As discussed in 
section IV above, manufacturers may use the ABT program and other 
flexibilities in achieving and demonstrating compliance.
---------------------------------------------------------------------------

    \306\ Diesel engines are engine-certified with the option to 
chassis certification Federally and for California.
---------------------------------------------------------------------------

    These rules will generally require complete HD pickups and vans to 
have CO2, CH4 and N2O values assigned 
to them, either from actual chassis dynamometer testing or from the 
results of a representative vehicle in the test group with appropriate 
adjustments made for differences. Manufacturers will be allowed to 
exclude vehicles they sell to secondary manufacturers as incomplete 
vehicles, unless these vehicles are chassis-certified for criteria 
(non-GHG) pollutants. To the extent manufacturers are allowed to 
engine- or chassis-certify for criteria pollutant requirements today, 
they will be allowed to continue to do so under the final regulations. 
See subsection V.B(1)(e) for discussion of special provisions for 
chassis-certification to GHG and fuel consumption standards.
    Because this program for heavy-duty pickup trucks and vans is so 
similar to the program recently adopted for light-duty trucks and 
codified in 40 CFR part 86, subpart S, EPA will apply most of those 
subpart S regulatory provisions to heavy-duty pickup trucks and vans 
and not recodify them in the new part 1037. Most of the new part 1037 
thus would not apply for heavy-duty pickup trucks and vans. How 40 CFR 
part 86 applies, and which provisions of the new 40 CFR part 1037 apply 
for heavy-duty pickup trucks and vans is described in Sec.  1037.104. 
Similarly NHTSA's requirements for these vehicles in Sec.  535.6(a) are 
based on 40 CFR part 86.
(a) Certification Process
    CAA section 203(a)(1) prohibits manufacturers from introducing a 
new motor vehicle into commerce unless the vehicle is covered by an 
EPA-issued certificate of conformity. Section 206(a)(1) of the CAA 
describes the requirements for EPA issuance of a certificate of 
conformity, based on a demonstration of compliance with the emission 
standards established by EPA under section 202 of the Act. The 
certification demonstration requires emission testing, and 
certification is required for each model year.\307\
---------------------------------------------------------------------------

    \307\ CAA Section 206(a)(1).
---------------------------------------------------------------------------

    Under existing heavy-duty chassis certification and other EPA 
emission standard programs, vehicle manufacturers certify a group of 
vehicles called a test group. A test group typically includes multiple 
vehicle car lines and model types that share critical emissions-related 
features.\308\
---------------------------------------------------------------------------

    \308\ The specific test group criteria are described in 40 CFR 
86.1827-01, car lines and model types have the meaning given in 40 
CFR 86.1803-01.
---------------------------------------------------------------------------

    EPA requires the manufacturer to make a good faith demonstration in 
the certification application that vehicles in the test group will both 
(1) comply throughout their useful life within the emissions bin 
assigned, and (2) contribute to fleetwide compliance with the 
applicable emissions standards when the year is over. EPA issues a 
certificate for the vehicles included in the test group based on this 
demonstration, and includes a condition in the certificate that if the 
manufacturer does not comply with the fleet average, then production 
vehicles from that test group will be treated as not covered by the 
certificate to the extent needed to bring the manufacturer's fleet 
average into compliance with the applicable standards.
    The certification process often occurs several months prior to 
production and manufacturer testing may occur months before the 
certificate is issued. The certification process for the existing 
heavy-duty chassis program is an efficient way for manufacturers to 
conduct the needed testing well in advance of certification, and to 
receive certificates in a time frame which allows for the orderly 
production of vehicles. The use of conditions on the certificate has 
been an effective way to ensure that manufacturers comply throughout 
their useful life and meet fleet standards when the model year is 
complete and the accounting for the individual model sales is 
performed. EPA has also adopted this approach as part of its light-duty 
vehicle GHG compliance program.
    These rules will similarly condition each certificate of conformity 
for the GHG program upon a manufacturer's good faith demonstration of 
compliance with the manufacturer's fleetwide average CO2 
standard. The following discussion explains how the agencies will 
integrate this new vehicle certification program into the existing 
certification program.
    An integrated approach with NHTSA has been undertaken to allow 
manufacturers a single point of entry to address certification and 
compliance. Vehicle manufacturers will initiate the formal 
certification process with their submission of application for a 
certificate of conformity to EPA, similar to the light-duty program.
(b) Certification Test Groups and Test Vehicle Selection
    For heavy-duty chassis certification to the criteria emission 
standards, manufacturers currently, as mentioned above, divide their 
fleet into ``test groups'' for certification purposes. The test group 
is EPA's unit of certification; one certificate is issued per test 
group/evaporative family combination. These groupings cover vehicles 
with similar emission control system designs expected to have similar 
emissions performance (see 40 CFR 86.1827-01). The factors considered 
for determining test groups include Gross Vehicle Weight, combustion 
cycle, engine type, engine displacement, number of cylinders and 
cylinder arrangement, fuel type, fuel metering system, catalyst 
construction and precious metal composition, among others. Vehicles 
having these features in common are generally placed in the same test 
group.\309\
---------------------------------------------------------------------------

    \309\ EPA provides for other groupings in certain circumstances, 
and can establish its own test groups in cases where the criteria do 
not apply. See 40 CFR 86.1827-01(b), (c) and (d).
---------------------------------------------------------------------------

    This program will retain the current test group structure for 
heavy-duty

[[Page 57258]]

pickups and vans in the certification requirements for CO2 
and fuel consumption. At the time of certification, manufacturers will 
use the CO2 emission level from the Emission Data Vehicle as 
a surrogate to represent all of the models in the test group. However, 
following certification further testing will generally be allowed for 
compliance with the fleet average CO2 and fuel consumption 
standards as described below. EPA's issuance of a certificate will be 
conditioned upon the manufacturer's subsequent model level testing and 
attainment of the actual fleet average, much like light-duty CAFE and 
GHG compliance requires. Under the current program, complete heavy-duty 
Otto-cycle vehicles under 14,000 pounds Gross Vehicle Weight Rating are 
required to chassis certify (see 40 CFR 86.1801-01(a)). The current 
program allows complete heavy-duty diesel vehicles under 14,000 pounds 
GVWR to optionally chassis certify (see 40 CFR 86.1863-07(a)). The new 
regulations we are adopting will not change these existing EPA 
certification options for complete (or incomplete) HD vehicles. EPA 
recognizes that the existing heavy-duty chassis test group criteria do 
not necessarily relate to CO2 emission levels. See 75 FR 
25472 (addressing the same issue for light-duty vehicles). For 
instance, while some of the criteria, such as combustion cycle, engine 
type and displacement, and fuel metering, may have a relationship to 
CO2 emissions, others, such as those pertaining to the some 
exhaust aftertreatment features, may not. In fact, there are many 
vehicle design factors that impact CO2 generation and 
emissions but are not major factors included in EPA's test group 
criteria.\310\ Most important among these may be vehicle weight, 
horsepower, aerodynamics, vehicle size, and performance features. To 
remedy this, EPA will allow manufacturers provisions that are similar 
to the light-duty vehicle rule that would yield more accurate 
CO2 estimates than only using the test group emission data 
vehicle CO2 emissions.
---------------------------------------------------------------------------

    \310\ EPA noted this potential lack of connection between fuel 
economy testing and testing for emissions standard purposes when it 
first adopted fuel economy test procedures. See 41 FR 38677, Sept. 
10, 1976.
---------------------------------------------------------------------------

    EPA believes that the current test group concept is appropriate for 
N2O and CH4 because the technologies that would 
be employed to control N2O and CH4 emissions may 
generally be the same as those used to control the criteria pollutants. 
However, manufacturers will determine if this approach is adequate 
method for N2O and CH4 emissions compliance or if 
testing on additional vehicles is required to ensure their entire fleet 
meets applicable standards.
    As just discussed, the ``worst case'' vehicle a manufacturer 
selects as the Emissions Data Vehicle to represent a test group under 
the existing regulations (40 CFR 86.1828-01) may not have the highest 
levels of CO2 in that group. For instance, there may be a 
heavier, more powerful configuration that would have higher 
CO2, but may, due to the way the catalytic converter has 
been matched to the engine, actually have lower NOX, CO, PM 
or HC emissions. Therefore, EPA is allowing the use of a single 
Emission Data Vehicle to represent the test group for both criteria 
pollutant and CO2 certification. The manufacturer will be 
allowed to initially apply the Emission Data Vehicle's CO2 
emissions value to all models in the test group, even if other models 
in the test group are expected to have higher CO2 emissions. 
However, as a condition of the certificate, this surrogate 
CO2 emissions value will generally be replaced with actual, 
model-level CO2 values based on results from additional 
testing that occurs later in the model year much like the light-duty 
CAFE program, or through the use of approved methods for analytically 
derived fuel economy. This model level data will become the official 
certification test results (as per the conditioned certificate) and 
will be used to determine compliance with the fleet average. If the 
test vehicle is in fact the worst case CO2 vehicle for the 
test group, the manufacturer may elect to apply the Emission Data 
Vehicle emission levels to all models in the test group for purposes of 
calculating fleet average emissions. Manufacturers may be unlikely to 
make this choice, because doing so would ignore the emissions 
performance of vehicle models in their fleet with lower CO2 
emissions and would unnecessarily inflate their CO2 fleet 
average. Testing at the model level, in order to better represent the 
improved performance of vehicles within a test group other than the 
Emission Data Vehicle, will necessarily increase testing burden beyond 
the minimum EDV testing.
    As explained in earlier Sections, there are two standards that the 
manufacturer will be subject to, the fleet average standard and the in-
use standard for the useful life of the vehicle. Compliance with the 
fleet average standard is based on production weighted averaging of the 
test data that applies for each model. To address commenter concerns 
regarding test variability due to facility and build variation for each 
model, the in-use and SEA standards are set at 10 percent higher than 
the level used for that model in calculating the fleet average. The 
certificate covers both of the fleet and in-use standards, and the 
manufacturer has to demonstrate compliance with both of these standards 
for purposes of receiving a certificate of conformity. The 
certification process for the in-use standard is discussed above.
(c) Demonstrating Compliance

(i) CO2 and Fuel Consumption Fleet Standards

    As noted, attribute-based CO2 and fuel consumption 
standards result in each manufacturer having fleet average 
CO2 and fuel consumption standards unique to its heavy-duty 
truck fleet of GVWR between 8,500-14,000 pounds and that standard will 
be separate from the standard for passenger cars, light-trucks, and 
other heavy-duty trucks. The standards depend on those attributes 
corresponding to the relative capability, or ``work factor'', of the 
vehicle models produced by that manufacturer. The final attributes used 
to determine the stringency of the CO2 and fuel consumption 
standards are payload and towing capacity as described in Section II. 
Generally, fleets with a mix of vehicles with increased payloads or 
greater towing capacity (or utilizing four wheel drive configurations) 
will face numerically less stringent standards (i.e., higher 
CO2 grams/mile standards or fuel consumption gallons/100 
miles standards) than fleets consisting of less powerful vehicles. 
(However, the standards will be expected to be equally challenging and 
achieve similar percent reductions.) Although a manufacturer's fleet 
average standard could be estimated throughout the model year based on 
projected production volume of its vehicle fleet, the final compliance 
values will be based on the final model year production figures. A 
manufacturer's calculation of fleet average emissions and fuel 
consumption at the end of the model year will be based on the 
production-weighted average emissions and fuel consumption of each 
model in its fleet. The payload and towing capacity inputs used to 
determine manufacturer compliance will be the advertised values.
    The agencies will use the same general vehicle category definitions 
that are used in the current EPA HD chassis certification (See 40 CFR 
86.1816-05). The new vehicle category definitions differ slightly from 
the EPA definitions for Heavy-duty Vehicle definitions for the existing 
program, as well as other EPA vehicle programs. Mainly,

[[Page 57259]]

manufacturers will be able to test, and possibly model, more 
configurations of vehicles than were historically possible. The 
existing criteria pollutant program requires the worst case 
configuration be tested for emissions certification. For HD chassis 
certification, this usually meant only testing the vehicle with the 
highest ALVW, road-load, and engine displacement within a given test 
group. This worst case configuration may only represent a small 
fraction of the test group production volume. By testing the worst 
case, albeit possibly small volume, vehicle configuration, the EPA had 
a reasonable expectation that all represented vehicles would pass the 
given emissions standards. Since CO2 standards are a fleet 
standard based on a combination of sales volume and work factor (i.e., 
payload and towing capability), it may be in a manufacturer's best 
interest to test multiple configurations within a given test group to 
more accurately estimate the fleet average CO2 emission 
levels and not accept the worst case vehicle test results as 
representative of all models. Additionally, vehicle models for which a 
manufacturer desires to use analytically derived fuel economy (ADFE) to 
estimate CO2 emission levels may need additional actual test 
data for vehicle models of similar but not identical configurations. 
The agencies are allowing the use of ADFE similar to that allowed for 
light-duty vehicles in 40 CFR 600.006-08(e). Some commenters, including 
the American Automotive Policy Council, were concerned that adopting 
the light-duty ADFE program with its current minimum test requirements 
would unduly increase testing burden. In addition to concerns over 
implementing the light-duty ADFE program for heavy-duty GHG compliance, 
commenters noted the need to develop a new HD ADFE methodology that 
addressed unique HD concerns. EPA and NHTSA have continued to work with 
stakeholders to address the above concerns with using a modified LD 
ADFE program. To address these concerns, the agencies will expand the 
allowed use of ADFE beyond that which is allowed in the LD program. 
Since ADFE equations are not final at the time of this action, updates 
to the HD ADFE program will be made through guidance or future 
rulemaking. The GHG and fuel economy rulemaking for light-duty vehicles 
adopted a carbon balance methodology used historically to determine 
fuel consumption for the light-duty labeling and CAFE programs, whereby 
the carbon-related combustion products HC and CO are included on an 
adjusted basis in the compliance calculations, along with 
CO2. The resulting carbon-related exhaust emissions (CREE) 
of each test vehicle are calculated and it is this value, rather than 
simply CO2 emissions, that is used in compliance 
determinations. The difference between the CREE and CO2 is 
typically very small. See generally 75 FR at 25472.
    NHTSA and EPA are not adopting the CREE methodology for HD pickups 
and vans, and so will not adjust CO2 emissions to further 
account for additional HC and CO. The basis of the CREE methodology in 
historical labeling and CAFE programs is not relevant to HD pickups and 
vans, because these historical programs do not exist for HD vehicles. 
Furthermore, test data used in this rulemaking for standards-setting 
has not been adjusted for this effect, and so it would create an 
inconsistency, albeit a small one, to apply it for compliance with the 
numerical standards we are finalizing. Finally, it would add complexity 
to the program with little real world benefit.
(ii) CO2 In-Use Standards and Testing
    Section 202(a)(1) of the CAA requires emission standards to apply 
to vehicles throughout their statutory useful life. Section II 
discusses in-use standards.
    Currently, EPA regulations require manufacturers to conduct in-use 
testing as a condition of certification for heavy-duty trucks between 
8,500 and 14,000 gross vehicle weight that are chassis certified. The 
vehicles are tested to determine the in-use levels of criteria 
pollutants when they are in their first and third years of service. 
This testing is referred to as the In-Use Verification Program, which 
was first implemented as part of EPA's CAP 2000 certification program 
(see 64 FR 23906, May 4, 1999).
    An in-use program was already set forth in the light-duty 2012-2016 
MY vehicle rule similar to the heavy-duty pickups and vans. The In-Use 
Verification Program for heavy-duty pickups and vans will follow the 
same general provisions of the light-duty program in regard to testing, 
vehicle selection, and reporting. See 75 FR 25474-25476.
(d) Special Provisions for Chassis Certification
    We proposed to include most cab-chassis Class 2b and 3 vehicles 
(vehicles sold as incomplete vehicles with the cab substantially in 
place but without the primary load-carrying enclosure) in the complete 
HD pickup and van program. Because their numbers are relatively small, 
and to reduce the testing and compliance tracking burden to 
manufacturers, we proposed to treat these vehicles as equivalent to the 
complete van or truck product from which they are derived. The 
manufacturer would determine which complete vehicle configuration it 
produces most closely matches the cab-chassis product leaving its 
facility, and would include each of these cab-chassis vehicles in the 
fleet averaging calculations as though it were identical to the 
corresponding complete ``sister'' vehicle. See 75 FR at 74263.
    Commenters opposed this proposed requirement for a number of 
reasons: (1) It would have the unintended consequence of dual 
certification for some of these vehicles--engine certification for 
criteria pollutants and vehicle certification for GHGs, and vice-versa 
for some other vehicles, (2) it would be of modest benefit because most 
of these cab-chassis vehicles would receive the desired aerodynamic and 
other non-engine improvements even without chassis certification, in 
virtue of their derivation from complete vehicles, and (3) a readily-
identifiable sister vehicle may not exist in every case. Based on the 
comments, the agencies have re-evaluated the proposed approach for cab-
chassis certification and are restructuring our compliance approach to 
provide significantly more flexibility while still ensuring comparable 
or better GHG and fuel consumption performance overall.
    We are not requiring that cab-chassis vehicles be chassis-
certified, but are retaining chassis-certification for them as an 
option using the proposed sister vehicle concept. We are instead 
requiring that vehicles that are chassis-certified for criteria 
pollutants be chassis-certified for GHGs and fuel consumption, and 
likewise that vehicles with engines certified for criteria pollutants 
(which in this case would be engines installed in vocational vehicles 
exclusively) be certified to the vocational vehicle standards for GHGs 
and fuel consumption, with minor exceptions detailed below. We believe 
that this approach involving consistent chassis- and engine-
certification for criteria pollutants and GHGs is the most sensible way 
to structure a program to minimize both the testing burden and the 
potential for gaming.
    We are allowing use of the sister vehicle concept for incomplete 
vehicle certification to include the selection of sister vehicles not 
actually produced for sale by the certifying manufacturer. For the 
great majority of vehicles this will not be an issue because the sister 
vehicle will obviously be the complete pickup truck or van from which 
the cab-chassis vehicle is derived. However if

[[Page 57260]]

the complete sister vehicle ceases production but the corresponding 
incomplete vehicle does not, a manufacturer may continue to use the 
sister vehicle emissions data through the carryover process that is 
already practiced today. If carryover is not appropriate because of, 
for example, an emissions-impacting recalibration of the engine, the 
manufacturer may conduct new emissions testing using the coastdown data 
collected on the original sister vehicle. This would still save 
substantial effort without sacrificing data quality because coastdowns 
are rather resource-intensive but are not much affected by engine 
changes. Another potentially inappropriate situation would exist where 
no sister vehicle exists because the manufacturer does not sell a 
related complete vehicle. In this case, the manufacturer may coastdown 
a mocked-up vehicle made from its incomplete vehicle and an added open 
or closed cargo box that simulates a complete van or pickup truck, or 
may coastdown one of its customers' completed vehicles.
    EPA and NHTSA requested comment on whether Class 4 vehicles that 
are very similar to complete Class 3 pickup truck models should be 
chassis-certified and regulated as part of the HD pickup and van 
category, instead of as vocational vehicles. Commenters argued 
convincingly that there are a number of important differences between 
the Class 4 and Class 3 trucks that make such regulation inappropriate 
as a general matter. As a result, we are keeping Class 4 trucks in the 
vocational vehicle category. However, we are adding an optional 
provision that allows manufacturers to certify Class 4 or 5 (14,001 to 
19,500 lb GVWR) complete or incomplete vehicles to GHG and fuel 
consumption standards, in the same way as Class 2b and 3 vehicles, and 
thus be included within the Class 2b/3 fleet average. The engines in 
these vehicles will continue to be engine-certified for criteria 
pollutants, but the manufacturers could include the vehicles in their 
fleet average standard and annual compliance calculations, using the 
same certification and compliance provisions as for the smaller 
vehicles, including the equations for determining work factors and 
target standards, in-use requirements, reporting requirements, credit 
generation and use, and sister vehicle provisions for incomplete 
vehicles. Such vehicles would not be required to meet the vocational 
vehicle standards. Because sales volumes of Class 4 and 5 trucks are 
relatively small, and because we expect these Class 4 and 5 and Class 
2b and 3 trucks to generally use the same technologies and face roughly 
the same technology challenge in meeting their standards targets, we do 
not believe that this provision will dilute the stringency of the fleet 
average standards.
    Any in-use testing of vehicles that are chassis-certified using the 
sister vehicle provisions would involve loading of the tested vehicle 
to a total weight equal to the ALVW of the corresponding complete 
vehicle configuration. If the secondary manufacturer had altered or 
replaced any vehicle components in a way that would substantially 
affect CO2 emissions from the tested vehicle (e.g., axle 
ratio has been changed for a special purpose vehicle), the vehicle 
manufacturer could request that EPA not test the vehicle or invalidate 
a test result. Secondary (finisher) manufacturers who finish incomplete 
vehicles certified using the sister vehicle provisions would not be 
subject to requirements under these regulations, other than to comply 
with anti-tampering regulations. However, if they modify vehicle 
components in such a way that GHG emissions and fuel consumption are 
substantially affected, they become manufacturers subject to the 
standards we are establishing in these rules.
    Finally, we are adopting a related special provision involving 
chassis-certification aimed at simplifying compliance for manufacturers 
of complete HD pickups and vans that also sell a relatively small 
number of engines that are designed for other manufacturers' heavy-duty 
vehicles--normally referred to as `loose' engines. Today these loose 
engines must be engine-certified for criteria pollutants, even though 
most of the vehicles that use the engines are chassis-certified. Our 
new provision does not change this, but it does provide manufacturers 
with an option to focus their energy on improving the GHG and fuel 
consumption performance of their complete vehicle products (including, 
most likely, significant engine improvements), rather than on 
concurrently calibrating for both vehicle and engine test compliance.
    These loose engines would not be certified to engine-based GHG and 
fuel consumption standards, but instead would be treated as though they 
were additional sales of the manufacturer's complete pickup and van 
products, on a one-for-one basis. The pickup/van vehicle so chosen must 
be the vehicle with the highest ETW that uses the engine (as this 
vehicle is likely to have the highest GHG emissions and fuel 
consumption). However, if this vehicle is a credit-generator under the 
HD pickup and van fleet averaging program, no credits would be 
generated by these engine-as-vehicle contributors to the fleet average; 
they would be treated as just achieving the target standard. If, on the 
other hand, the vehicle is a credit-user, the appropriate number of 
additional credits would be needed to offset the engine-as-vehicle 
contributors. The purchaser of the engine would treat it as any other 
certified engine, and would still need to meet applicable vocational 
vehicle standards for the vehicles in which the engine is installed.
    Because it is our intent that this loose engine provision 
simplifies compliance for HD pickup/van manufacturers who sell a 
relatively small number of engines for other manufacturers' 
applications, we are limiting its use to 10 percent of the total 
engines (15,000 maximum) of the same design that a manufacturer 
produces in each model year for U.S.-directed heavy-duty application--
including complete vehicles, incomplete vehicles, and the loose engines 
themselves. We are further limiting both this provision and the above-
described provision for chassis certification of Class 4/5 vehicles to 
spark-ignition (gasoline) engines, because we believe that the HD 
diesel engine business is more focused on designing for and marketing 
into a wide variety of vehicles products, instead of into the engine 
manufacturer's own chassis-certified vehicle products with a small 
loose engine business on the side, as is common for HD gasoline 
engines. This dynamic is also reflected in the existing provision for 
criteria pollutants allowing complete HD vehicles to use certified 
diesel engines but not certified gasoline engines.
    Together these provisions provide a robust approach to regulating 
these vehicles and engines. Although these certification options are 
not as straightforward as the certification provisions for complete 
Class 2b/3 pickups and vans, they are technically appropriate (for the 
reasons explained above) and should accomplish more improvement in GHG 
and fuel consumption performance than simply applying the vocational 
vehicle and engine standards.
(2) Labeling Provisions
    HD pickups and vans currently have vehicle emission control 
information labels showing compliance with criteria pollutant 
standards, similar to emission control information labels for engines. 
As with engines, we believe this label is sufficient.

[[Page 57261]]

(3) Other Certification Issues
(a) Carryover Certification Test Data
    EPA's final certification program for vehicles allows manufacturers 
to carry certification test data over from one model year to the next, 
when no significant changes to models are made. EPA will also apply 
this policy to CO2, N2O and CH4 
certification test data.
(b) Compliance Fees
    The CAA allows EPA to collect fees to cover the costs of issuing 
certificates of conformity for the classes of vehicles and engines 
covered by this rulemaking. On May 11, 2004, EPA updated its fees 
regulation based on a study of the costs associated with its motor 
vehicle and engine compliance program (69 FR 51402). At the time that 
cost study was conducted the current rulemaking was not considered.
    At this time the extent of any added costs to EPA as a result of 
this rulemaking is not known. EPA will assess its compliance testing 
and other activities associated with the program and may amend its fees 
regulations in the future to include any justifiable new costs.
(4) Compliance Reports
(a) Pre-Model Year Report
    In the NPRM, EPA and NHTSA proposed that manufacturers must submit 
early model year compliance reports demonstrating how their entire 
fleets of heavy-duty pickup trucks and vans would comply with GHG 
emissions and fuel consumption standards. The agencies understood that 
early model year reports would contain estimates that may change over 
the course of a model year and that compliance information manufactures 
submit prior to the beginning of a new model year may not represent the 
final compliance outcome. The agencies viewed the necessity for 
requiring early model reports as a manufacturer's good faith projection 
for demonstrating compliance with emission and fuel consumption 
standards. The preamble language indicated that the compliance reports 
would be submitted prior to the beginning of the model year and prior 
to the certification of any test group. Preferably, a manufacturer 
would submit its reports during its annual certification preview 
meeting. Precertification preview meetings are typically held with a 
manufacturer before the earliest date that the model year can begin 
which is January 2nd of the calendar year prior to the model year. 
Manufacturers voluntarily choose to participate in precertification 
compliance meetings but meetings are not required by EPA and NHTSA 
regulations. Manufacturers opt to participate in precertification 
meetings because of the advantage it gives to exploring with the 
agencies any possible compliance problems that may arise prior to 
seeking approval for certificates of conformity. The NPRM preamble text 
did not specify an exact date for manufacturers to submit early 
compliance reports to the agency. NHTSA attempted to adopt requirements 
in its regulatory text for manufactures to submit their early 
compliance reports no later than the end of December two years prior to 
the model year. NHTSA also proposed for manufacturers to provide 
compliance information for the current model year and to the extent 
possible two years into the future. NHTSA chose its submission deadline 
and model years for reporting based upon the same dates required by EPA 
in its CAFE provisions for light-duty pickups and vans beginning in 
model year 2012.
    The NPRM included requirements for manufacturers to submit early 
model year compliance reports separately to each agency based upon 
limitations existing in the statutory authorities prescribed under EISA 
and CAA and the long-standing precedent set in the LD CAFE programs for 
receiving reports. The EPA report, called the pre-model year report, 
and NHTSA report, called the pre-certification compliance report, were 
proposed to include an estimate of the manufacturer's attribute-based 
standards, along with a demonstration of compliance with the standards 
based on projected model-level and fleet CO2 emissions and 
fuel consumption results, and were to include an estimate of the 
manufacturer's production volumes. The NPRM also included a proposal 
for submitting a credit plan for manufacturers seeking to take 
advantage of credit flexibilities and a credit deficit plan for 
manufacturers planning to accrue deficits during the model years. 
Additionally, NHTSA attempted to reduce the burden on manufacturers by 
allowing them to submit copies of EPA's proposed pre-model year reports 
or applications for certifications of conformity, as a substitute to 
its own compliance report, so long as EPA's reports were submitted with 
equivalent fuel consumption information. In either case, NHTSA reserved 
the right to ask manufacturers to provide additional information if 
necessary to verify its fuel consumption requirements under this 
program. EPA and NHTSA also proposed to review the compliance reports 
for technical viability and to conduct a certification preview 
discussion with the manufacturer. It was further proposed that the EPA 
Administrator would have to approve a manufacturer's pre-model year 
report before it would consider issuing any certificate of compliance 
for the manufacturer.
    Comments were received to the NPRM from EMA and TMA strongly 
opposing providing separate reports to EPA and NHTSA and requested that 
the agencies implement a single uniform reporting template that could 
be submitted to both agencies simultaneously. DTNA requested that NHTSA 
eliminate its pre-certification compliance report, arguing that report 
was overly burdensome.
    For the final rules, the agencies have decided to require 
manufacturers to submit a single report, hereafter referenced as the 
pre-model year report, to satisfy both agencies requirements for 
receiving compliance reports in advance of the model year. The agencies 
considered the commenters' requests and determined that the benefit 
gained by receiving separate or distinct compliance reports would not 
outweigh the burden placed on manufacturers in reporting. Therefore, 
the final rules establish a harmonized approach by which manufacturers 
will submit a single report through the EPA database system as the 
single point of entry for all information required for this national 
program and both agencies will have access to the information. If by 
model year 2012, the agencies are not prepared to receive information 
through the EPA database system, manufacturers are expected to submit 
written reports to the agencies. EPA and NHTSA have determined that 
requiring manufacturers to submit a joint pre-model year report for 
their combined fleet of heavy-duty pickup trucks containing both 
emissions and equivalent fuel consumption information falls within each 
agencies' statutory authority. The final rules require a manufacturer 
to submit the joint pre-model year report as early as the date of the 
manufacturer's annual certification preview meeting, or prior to the 
manufacturer submitting its first application for a certificate for the 
given model year. Consequently, a manufacturer choosing to comply in 
model year 2014 could submit its pre-model year report during its 
precertification meeting, which could occur before January 2, 2013. 
Alternately, the manufacturer could provide its pre-model year report 
any time prior to submitting its first application. In either case, a 
manufacturer would not be able to certify any of its test groups until 
the

[[Page 57262]]

EPA Administrator approves its pre-model year report. NHTSA will use 
the pre-model year report as preliminary model year data.
    The agencies are adopting similar requirements for the pre-model 
year reports as proposed. As mentioned, the agencies proposed that 
reports would include an estimate of the manufacturer's attribute-based 
standards, expected testing results and estimated production volumes. 
The agencies agree that this information is essential for tracking 
compliance of manufacturers and is therefore adopted for the final 
rules. The final rules require manufacturers to identify any vehicle 
exclusions and other flexibilities afforded for heavy-duty pickups and 
vans. The summary of the required information for each pre-model year 
report is as follows:
     A list of each unique vehicle configuration included in 
the manufacturer's fleet describing the make and model designations, 
attribute based-values (GVWR, GCWR, Curb Weight and drive 
configurations) and standards.
     The emission and fuel consumption fleet average standard 
derived from the unique vehicle configurations;
     The estimated vehicle configuration, test group and fleet 
production volumes;
     The expected emissions and fuel consumption test group 
results and fleet average performance;
     A statement declaring whether the manufacturer chooses to 
comply early in MY 2013 for EPA and NHTSA. The manufacturers must 
acknowledge that once selected, the decision cannot be reversed and the 
manufacturer will continue to comply with the fuel consumption 
standards for subsequent model years;
     A statement declaring whether the manufacturer will use 
fixed or increasing standards; acknowledging that once selected, the 
decision cannot be reversed and the manufacturer must continue to 
comply with the same alternative for subsequent model years;
     A statement declaring whether the manufacturer chooses to 
comply voluntarily with NHTSA's fuel consumption standards for model 
years 2014 through 2015. The manufacturers must acknowledge that once 
selected, the decision cannot be reversed and the manufacturer will 
continue to comply with the fuel consumption standards for subsequent 
model years;
     The list of Class 2b-3 cab-complete vehicles and the 
method use to certify, as vocational vehicles and engines, or as 
complete pickups and vans identifying the most similar complete 
vehicles used to derive the target standards and performance test 
results;
     The list of Class 2b-3 incomplete vehicles and the method 
use to certify, as vocational vehicles and engines, or as complete 
pickups and vans identifying the most similar complete vehicles used to 
derive the target standards and performance test results;
     The list of Class 4 and 5 incomplete and complete vehicles 
and the method use to certify, as vocational vehicles and engines, or 
as complete pickups and vans identifying the most similar complete 
vehicles used to derive the target standards and performance test 
results;
     List of loose engines included in the heavy-duty pickup 
and van category and the list of vehicles used to derive target 
standards.
     Copy of any notices a vehicle manufacturer sends to the 
engine manufacturer to notify the engine manufacturers that their 
engines are subject to emissions and fuel consumption standards and 
that it intends to use their engines in excluded vehicles; and
     A credit plan identifying the manufacturers estimated 
credit balances, planned credit flexibilities (i.e., credit balances, 
planned credit trading, innovative, advanced and early credits and 
etc.) and if needed a credit deficit plan demonstrating how it plans to 
resolve any credit deficits that might occur for a model year within a 
period of up to three model years after that deficit has occurred.
(b) Final Reports
    The NPRM proposed for manufacturers participating in the ABT 
program to provide two types of year end reports; end-of-the-year (EOY) 
reports and final reports. The EOY reports for the ABT program were 
required to be submitted by manufacturers no later than 90 days after 
the calendar year and final report no later than 270 days after the 
calendar year.\311\ Manufacturers not participating in the ABT program 
were required to provide an EOY report within 45 days after the 
calendar year but no final reports were required. The submission 
deadline of the final ABT report was established to coincide with EPA's 
existing criteria pollutant report for heavy-duty engines. The EOY 
report is used by the agencies to review a manufacturer's preliminary 
final estimates and to identify manufacturers that might have a credit 
deficit for the given model year. Manufacturers with a credit surplus 
at the end of each model year could submit a request to the agencies to 
receive a waiver from providing EOY reports. As proposed, the remaining 
manufacturers were required to submit reports to EPA and send copies of 
those reports to NHTSA with equivalent fuel consumption values. 
Manufacturers requesting to exempt vehicles in accordance with the 
agencies' off-road vehicle exemption were required to a submit EOY 
reports to the agencies identifying the vehicle applicable to each 
report within 90 days after the model year ended.
---------------------------------------------------------------------------

    \311\ Corresponding to the compliance model year
---------------------------------------------------------------------------

    Comments in response to the NPRM did not oppose providing EOY 
reports to the agencies but instead requested that they be allowed to 
consolidate the various EOY reports into one single submission to the 
agencies.
    Upon consideration of commenters' requests, the agencies agree that 
only one consolidated EOY report should be submitted in place of the 
separate reports proposed in the NPRM. The consolidated EOY report 
should include the combination of all the required information that is 
applicable to a manufacturer's fleet. The agencies also agree to allow 
manufacturers to no longer provide separate EOY reports to each agency 
independently but rather to submit the single report through the EPA 
database system as the single point of entry for all information 
required for this national program. The consolidated EOY report is 
required to contain both GHG emissions and fuel consumption 
information. EPA will provide access to the information for both 
agencies. Likewise, manufacturers will be required to electronically 
provide one single final report through the EPA database system. If by 
model year 2012, the agencies are not prepared to receive information 
through the EPA database system, manufacturers are expected to submit 
written reports to the agencies. The required information for EOY and 
final reports that manufacturers must submit is as follows: A finalized 
list of each unique vehicle configuration included in the manufacturers 
fleet describing the designations, attribute based-values (GVWR, GCWR, 
Curb Weight and drive configurations) and standards.
     The final emission and fuel consumption fleet average 
standard derived from the unique vehicle configurations;
     The final vehicle configuration, test group and fleet 
production volumes;
     The final emissions and fuel consumption test group 
results and fleet average performance;
     The final list of cab-complete vehicles and the method use 
to certify, as vocational vehicles and engine, or as

[[Page 57263]]

complete pickups and vans identifying the most similar complete 
vehicles used to derive the target standards and performance test 
results;
     A final credit plan identifying the manufacturers 
estimated credit balances, planned credit flexibilities (i.e., credit 
balances, planned credit trading, innovative, advanced and early 
credits, and etc.) and if needed a credit deficit plan demonstrating 
how it plans to resolve any credit deficits that might occur for a 
model year within a period of up to three model years after that 
deficit has occurred;
     A plan describing the vehicles that were exempted such as 
for off-road or small business purposes; and
     A plan describing any alternative fueled vehicles that 
were produced for the model year identifying the approaches used to 
determine compliance and the production volumes.

C. Heavy-Duty Engines

(i) Compliance Approach
    Section 203 of the CAA requires that all motor vehicles and engines 
sold in the United States carry a certificate of conformity issued by 
the U.S. EPA. For heavy-duty engines, the certificate specifies that 
the engine meets all requirements as set forth in the regulations (40 
CFR part 86, subpart N, for criteria pollutants) including the 
requirement that the engine be compliant with emission standards. This 
demonstration is completed through emission testing as well as 
durability testing to determine the level of emissions deterioration 
throughout the useful life of the engine. In addition to comply with 
emission standards, manufacturers are also required to warrant their 
products against emission defects, and demonstrate that a service 
network is in place to correct any such conditions. The engine 
manufacturer also bears responsibility in the event that an emission-
related recall is necessary. Finally, the engine manufacturer is 
responsible for tracking and ensuring correct installation of any 
emission related components installed by a second party (i.e., vehicle 
manufacturer). EPA and NHTSA believe this compliance structure is also 
valid for administering the final GHG regulations for heavy-duty 
engines.
(a) Certification Process
    In order to obtain a certificate of conformity, engine 
manufacturers must complete a compliance demonstration, normally 
consisting of test data from relatively new (low-hour) engines as well 
as supporting documentation, showing that their product meets emission 
standards and other regulatory requirements. To account for aging 
effects, low-hour test results are coupled with testing-based 
deterioration factors (DFs), which provide a ratio (or offset) of end-
of-life emissions to low-hour emissions for each pollutant being 
measured. These factors are then applied to all subsequent low-hour 
test data points to predict the emissions behavior at the end of the 
useful life.
    For purposes of this compliance demonstration and certification, 
engines with similar engine hardware and emission characteristics 
throughout their useful life may be grouped together in engine 
families, consistent with current criteria-pollutant certification 
procedures. Examples of such engine characteristics that are normally 
used to combine emissions families include similar combustion cycle, 
aspiration methods, and aftertreatment systems. Under this system, the 
worst-case engine (``parent rating'') is selected based on having the 
highest fuel feed per engine stroke, and all emissions testing is 
completed on this model. All other models within the family (``child 
ratings'') are expected to have emissions at or below the parent model 
and therefore in compliance with emission standards. Any engine within 
the family can be subject to selective enforcement audits, in-use, 
confirmatory, or other compliance testing.
    We are continuing the use of this approach for the selection of the 
worst-case engine (``parent rating'') for fuel consumption and GHG 
emissions as well. As at proposal, we believe this is appropriate 
because this worst case engine configuration would be expected to have 
the highest in-use fuel consumption and GHG emissions within the 
family. See 75 FR at 72264 for further information. We note that lower 
engine ratings contained within this family would be expected to have a 
higher fuel consumption rate when measured over the Federal Test 
Procedures as expressed in terms of fuel consumption per brake 
horsepower hour. However, this higher fuel consumption rate is 
misleading in the context of comparing engines within a single engine 
family. This apparent contradiction can be most easily understood in 
terms of an example. For a typical engine family a top rating could be 
500 horsepower with a number of lower engine ratings down to 400 
horsepower or lower included within the family. When installed in 
identical trucks the 400 and 500 horsepower engines would be expected 
to operate identically when the demanded power from the engines is 400 
horsepower or less. So in the case where in-use driving never included 
acceleration rates leading to horsepower demand greater than 400 
horsepower, the two trucks with the 400 and 500 horsepower engines 
would give identical fuel consumption and GHG performance. When the 
desired vehicle acceleration rates were high enough to require more 
than 400 horsepower, the 500 horsepower truck would accelerate faster 
than the 400 horsepower truck resulting in higher average speeds and 
higher fuel consumption and GHG emissions measured on a per mile or per 
ton-mile basis. Hence, the higher rated engine family would be expected 
to have the highest in-use fuel consumption and CO2 
emissions consistent with our current approach requiring manufacturers 
to certify the worst case configuration.
    As explained at proposal, the reason that the lower engine ratings 
appear to have worse fuel consumption relates to our use of a brake 
specific work metric. The brake specific metric measures power produced 
from the engine and delivered to the vehicle ignoring the parasitic 
work internal to the engine to overcome friction and air pumping work 
within the engine. The fuel consumed and GHG emissions produced to 
overcome this internal work and to produce useful (brake) work are both 
measured in the test cycle but only the brake work is reflected in the 
calculation of the fuel consumption rate. This is desirable in the 
context of reducing fuel consumption as this approach rewards engine 
designs that minimize this internal work through better engine designs. 
The less work that is needed internal to the engine, the lower the fuel 
consumption will be. If we included the parasitic work in the 
calculation of the rate, we would provide no incentive to reduce 
internal friction and pumping losses. However, when comparing two 
engines within the very same family with identical internal work 
characteristics, this approach gives a misleading comparison between 
two engines as described above. This is the case because both engines 
have an identical fuel consumption rate to overcome internal work but 
different rates of brake work with the higher horsepower rating having 
more brake work because the test cycle is normalized to 100 percent of 
the engine's rated power. The fuel consumed for internal work can be 
thought of as a fixed offset identical between both engines. When this 
fixed offset is added to the fuel consumed for useful (brake) work over 
the cycle, it increases the overall fuel consumption

[[Page 57264]]

(the numerator in the rate) without adding any work to the denominator. 
This fixed offset identical between the two engines has a bigger impact 
on the lower engine rating. In the extreme this can be seen easily. As 
the engine ratings decrease and approach zero, the brake work 
approaches zero and the calculated brake specific fuel consumption 
approaches infinity. For these reasons, we are finalizing that the same 
selection criteria, as outlined in 40 CFR part 86, subpart N, be used 
to define a single engine family designation for both criteria 
pollutant and GHG emissions. Further, we are finalizing that for fuel 
consumption and CO2 emissions only any selective enforcement 
audits, in-use, confirmatory, or other compliance testing would be 
limited to the parent rating for the family. Consistent with the 
current regulations, manufacturers may electively subdivide a grouping 
of engines which would otherwise meet the criteria for a single family 
if they have evidence that the emissions are different over the useful 
life. The agencies received comments from engine and truck 
manufacturers which indicated the useful life provisions applicable to 
criteria pollutants seemed appropriate for GHG emissions. For that 
reason, the agencies are retaining many of the same provisions for GHG 
certification for family useful life provisions as developed for 
criteria pollutants.
    EPA utilizes a 12-digit naming convention for all mobile-source 
engine families (and test groups for light-duty vehicles). This 
convention is also shared by the California Air Resources Board which 
allows manufacturers to potentially use a single family name for both 
EPA and California ARB certification. Of the 12 digits, 9 are EPA-
defined and provide identifying characteristics of the engine family. 
The first digit represents the model year, through use of a predefined 
code. For example, the code ``A'' corresponds to the 2010 model year 
and ``B'' corresponds to the 2011 model year. The 5th position 
corresponds to the industry sector code, which includes such examples 
as light-duty vehicle (V) and heavy-duty diesel engines (H). The next 
three digits are a unique alphanumeric code assigned to each 
manufacturer by EPA. The next four digits describe the displacement of 
the engine; the units of which are dependent on the industry segment 
and a decimal may be used when the displacement is in liters. For 
engine families with multiple displacements, the largest displacement 
is used for the family name. For on-highway vehicles and engines, the 
tenth character is reserved for use by California ARB. The final 
characters (including the 10th character in absence of California ARB 
guidance) left to the manufacturer to determine, such that the family 
name forms a unique identifying characteristic of the engine family.
    This convention is well understood by the regulated industries, 
provides sufficient detail, and is flexible enough to be used across a 
wide spectrum of vehicle and engine categories. In addition, the 
current harmonization with other regulatory bodies reduces 
complications for affected manufacturers. For these reasons, we are not 
finalizing any major changes to this naming convention for this 
rulemaking. There may be additional categories defined for the 5th 
character to address heavy-duty vehicle families, however that will be 
discussed later.
    As with criteria pollutant standards, the heavy-duty diesel 
regulatory category is subdivided into three regulatory subcategories, 
depending on the GVW of the vehicle in which the engine will be used. 
These regulatory subcategories are defined as light-heavy-duty (LHD) 
diesel, medium heavy-duty (MHD) diesel, and heavy heavy-duty (HHD) 
diesel engines. All heavy-duty gasoline engines are grouped into a 
single subcategory. Each of these regulatory subcategories are expected 
to be in service for varying amounts of time, so they each carry 
different regulatory useful lives. For this reason, expectations for 
demonstrating useful life compliance differ by subcategory, 
particularly as related to deterioration factors.
    Light heavy-duty diesel engines (and all gasoline heavy-duty 
engines) have the same regulatory useful life as a light-duty vehicle 
(110,000 miles), which is significantly shorter than the other heavy-
duty regulatory subcategories. Therefore, we believe it is appropriate 
to maintain commonality with the light-duty vehicle rule. During the 
light-duty vehicle rulemaking, the conclusion was reached that no 
significant deterioration would occur over the useful life. Therefore, 
EPA is recommending that manufacturers use assigned DFs for 
CO2. For this final action, we believe appropriate values 
are zero (for additive DFs) and one (for multiplicative DFs). EPA will 
continue to collect data regarding deterioration of CO2 
emissions and may revisit these assigned values if necessary.
    For the medium heavy-duty and heavy heavy-duty diesel engine 
segments, the regulatory useful lives are significantly longer (185,000 
and 435,000 miles, respectively). For this reason, the EPA cannot rule 
out the possibility that engine/aftertreatment wear will have a 
negative impact on GHG emissions. To address useful life compliance for 
MHD and HHD diesel engines certified to GHG standards, EPA therefore 
believes that the criteria pollutant approach for developing DFs is 
appropriate. Using CO2 as an example, many types of engine 
deterioration will affect CO2 emissions. Reduced 
compression, as a result of wear, will cause higher fuel consumption 
and increase CO2 production. In addition, as aftertreatment 
devices age (primarily particulate traps), regeneration events may 
become more frequent and take longer to complete. Since regeneration 
commonly requires an increase in fuel rate, CO2 emissions 
would likely increase as well. Finally, any changes in EGR levels will 
affect heat release rates, peak combustion temperatures, and 
completeness of combustion. Since these factors could reasonably be 
expected to change fuel consumption, CO2 emissions would be 
expected to change accordingly. However, we expect engine manufacturers 
to consider performance degradation in the design of engine and 
aftertreatment systems given the market incentive to reduce fuel 
consumption and related CO2 emissions. For these reasons, 
EPA is not eliminating the DF from this program, but will allow for an 
assigned DF of zero.
    HHD diesel engines may also require some degree of aftertreatment 
maintenance throughout their useful life. For example, one major heavy-
duty engine manufacturer specifies that their diesel particulate 
filters be removed and cleaned at intervals between 200,000 and 400,000 
miles, depending on the severity of service. Another major engine 
manufacturer requires servicing diesel particulate filters at 300,000 
miles. This maintenance or lack thereof if service is neglected, could 
have serious negative implications to CO2 emissions. In 
addition, there may be emissions-related warranty implications for 
manufacturers to ensure that if rebuilding or specific emissions 
related maintenance is necessary, it will occur at the prescribed 
intervals. Therefore, it is imperative that manufacturers provide 
detailed maintenance instructions. Lean-NOX aftertreatment 
devices may also facilitate GHG reductions by allowing engines to run 
with higher engine-out NOX levels in exchange for more 
efficient calibrations. In most cases, these aftertreatment devices 
require a consumable reductant,

[[Page 57265]]

such as diesel exhaust fluid, which requires periodic maintenance by 
the vehicle operator. Without such maintenance, the emission control 
system may be compromised and compliance with emission standards may be 
jeopardized. Such maintenance is considered to be critical emission 
related maintenance and manufacturers must therefore demonstrate that 
it is likely to be completed at the required intervals. One example of 
such a demonstration is an engine power de-rating strategy that will 
limit engine power or vehicle speed in absence of this required 
maintenance.
    If the manufacturer determines that maintenance is necessary on 
critical emission-related components within the useful life period, it 
must have a reasonable basis for ensuring that this maintenance will be 
completed as scheduled. This includes any adjustment, cleaning, repair, 
or replacement of critical emission-related components. Typically, EPA 
has only allowed manufacturers to schedule such maintenance if the 
manufacturer can demonstrate that the maintenance is reasonably likely 
to be done at the recommended intervals. This demonstration may be in 
the form of survey data showing at least 80 percent of in-use engines 
get the prescribed maintenance at the correct intervals. Another 
possibility is to provide the maintenance free of charge. We see no 
reason to depart from this approach for GHG-related critical emission-
related components. For reasons stated previously regarding the useful 
life provisions, EPA is retaining many of the same provisions for GHG 
certification for family useful life provisions as developed for 
criteria pollutants.
(b) Demonstrating Compliance with the Standards
(i) CO2 Standards
    The final test results (adjusted for deterioration, if applicable) 
form the basis for the Family Certification Limit (FCL), which the 
manufacturer must specify to be at or above the certification test 
results. This FCL becomes the emission standard for the family and any 
certification or confirmatory testing must show compliance with this 
limit. In addition, manufacturers may choose an FCL at any level above 
their certified emission level to provide a larger compliance margin. 
If subsequent certification or confirmatory testing reveals emissions 
above the FCL, the new, higher result becomes the FCL.
    As proposed, the FCL is also used to determine the Family Emission 
Limit (FEL), which serves as the emission limit for any subsequent 
field testing conducted after the time of certification. This would 
primarily include selective enforcement audits, but also may include 
in-use testing for GHGs. The FEL differs from the FCL in that it 
includes an EPA-defined compliance margin; which has been defined at 3 
percent for the final rule. Our proposal included a two percent margin 
based on round-robin testing of the same engine at several 
laboratories. Since that time, additional confidential data provided by 
manufacturers has indicated that it may be more appropriate to use a 
three percent margin to also account for production variability between 
engines.\312\ Under this final action, the FEL will always be three 
percent higher than the FCL.
---------------------------------------------------------------------------

    \312\ See discussion in RIA 3.1.2.3.
---------------------------------------------------------------------------

Engine Emission Testing
    Under current non-GHG engine emissions regulations, manufacturers 
are required to demonstrate compliance using two test methods: the 
heavy-duty transient cycle and the heavy-duty steady state test. Each 
test is an engine speed versus engine torque schedule intended to be 
run on an engine dynamometer. Over each test, emissions are sampled 
using the equipment and procedures outlined in 40 CFR part 1065, which 
includes provisions for measuring CO2, N2O, and 
CH4. Emissions may be sampled continuously or in a batch 
configuration (commonly known as ``bag sampling'') and the total mass 
of emissions over each cycle are normalized by the engine power 
required to complete the cycle. Following each test, a validation check 
is made comparing actual engine speed and torque over the cycle to the 
commanded values. If these values do not align well, the test is deemed 
invalid.
    The transient Heavy-duty FTP cycle is characteristic of typical 
urban stop-and-go driving. Also included is a period of more steady 
state operation that would be typical of short cruise intervals at 45 
to 55 miles per hour. Each transient test consists of two 20 minute 
tests separated by a ``soak'' period of 20 minutes. The first test is 
run with the engine in a ``cold'' state, which involves letting the 
engine cool to ambient conditions either by sitting overnight or by 
forced cooling provisions outlined in Sec.  86.1335-90 (or 40 CFR part 
1036). This portion of the test is meant to assess the ability of the 
engine to control emissions during the period prior to reaching normal 
operating temperature. This is commonly a challenging area in criteria 
pollutant emission control, as cold combustion chamber surfaces tend to 
inhibit mixing and vaporization of fuel and aftertreatment devices do 
not tend to function well at low temperatures.
    Following the first test, the engine is shut off for a period of 20 
minutes, during which emission analyzer checks are performed and 
preparations are made for the second test (also known as the ``hot'' 
test). After completion of the second test, the results from the cold 
and hot tests are weighted and a single composite result is calculated 
for each pollutant. Based on typical in-use duty cycles, the cold test 
results are given a \1/7\ weighting and the hot test results are given 
a \6/7\ weighting. Deterioration factors are applied to the final 
weighted results and the results are then compared to the emission 
standards.
    Prior to 2007, compliance only needed to be demonstrated over the 
Heavy-duty FTP. However, a number of events brought to light the fact 
that this transient cycle may not be as well suited for engines which 
spend much of their duty cycle at steady cruise conditions, such as 
those used in line-haul semi-trucks. As a result, the steady-state SET 
procedure was added, consisting of 13 steady-state modes. During each 
mode, emissions were sampled for a period of five minutes. Weighting 
factors were then applied to each mode and the final weighted results 
were compared to the emission standards (including deterioration 
factors). In addition, emissions at each mode could not exceed the NTE 
emission limits. Alternatively, manufacturers could run the test as a 
ramped-modal cycle. In this case, the cycle still consists of the same 
speed/torque modes, however linear progressions between points are 
added and instead of weighting factors, each mode is sampled for 
various amounts of time. The result is a continuous cycle lasting 
approximately 40 minutes. With the implementation of part 1065 test 
procedures in 2010, manufacturers are now required to run the modal 
test as a ramped-modal cycle. In addition, the order of the speed/
torque modes in the ramped-modal cycle have changed for 2010 and later 
engines.
    It is well known that fuel consumption, and therefore 
CO2 emissions, are highly dependent on the drive cycle over 
which they are measured. Steady cruise conditions, such as highway 
driving, tend to be more efficient, having lower fuel consumption and 
CO2 emissions. In contrast, highly transient operation, such 
as city driving, tends to lead to lower efficiency and therefore higher 
fuel consumption and CO2 emissions. One example of this is 
the difference

[[Page 57266]]

between EPA-measured city and highway fuel economy ratings assigned to 
all new light-duty passenger vehicles.
    For this heavy-duty engine and vehicle rule, we believe it is 
important to assess CO2 emissions and fuel consumption over 
both transient and steady state test cycles, as all vehicles will 
operate in conditions typical of each cycle at some point in their 
useful life. However, due to the drive cycle dependence of 
CO2 emissions, we do not believe it is reasonable to have a 
single CO2 standard which must be met for both cycles. As we 
discussed at proposal, a single CO2 standard would likely 
prove to be too lax for steady-state conditions while being too strict 
for transient conditions. Therefore, the agencies are finalizing that 
all heavy-duty engines be tested over both transient and steady-state 
tests. However, only the results from either the transient or steady-
state test cycles will be used to assess compliance with GHG standards, 
depending on the type of vehicle in which the engine will be used. 
Engines that will be used in Class 7 and 8 combination tractors will 
use the ramped-modal cycle for GHG certification, and engines used in 
vocational vehicles will use the Heavy-duty FTP cycle. In both cases, 
results from the other test cycle will be reported but not used for a 
compliance decision. Engines will continue to be required to show 
criteria pollutant compliance over both cycles, in addition to NTE 
requirements.
    The agencies proposed that manufacturers submit both data sets from 
the transient test at the time of certification. This includes 
providing both cold start and hot start transient heavy-duty FTP 
emissions results, as well as the composite emissions at the time of 
certification. The proposed rules also required that manufacturers 
submit modal data from the ramped-modal cycle test. This was proposed 
in an effort to improve the accuracy of the simulation model being used 
for assessing CO2 and fuel consumption performance and 
overall engine emissions performance.
    However several commenters were concerned that modal data was non-
discernable when batch sampling was used for certification testing. 
Thus, an additional certification test (or tests) would need to be done 
using either continuous analyzers or batch sampling at each mode; each 
option raising the cost and complexity of certification testing. The 
agencies agree that (at this time) this raises practical issues for 
certification testing, however we also believe that manufacturers have 
significant data from these modal points which could be used to satisfy 
our model refinement goals.
    The agencies also recognize that even minor variations in test fuel 
properties can have an impact on measured CO2 emissions. 
Therefore, measured CO2 results are to be corrected using a 
reference energy content, which is defined in the regulations. This 
correction must be performed for each test and each batch of test fuel. 
However, manufacturers may develop robust testing procedures that 
reduce the variation in test fuel properties to within the level of 
measurement uncertainty of the fuel properties themselves. If this is 
the case, an annual review is still necessary to confirm the validity 
of this constant value.
    As explained above in Section II, the agencies are finalizing an 
alternative standard whereby manufacturers may elect that certain of 
their engine families meet an alternative percent reduction standard, 
measured from the engine family's 2011 baseline, instead of the main 
2014 MY standard. As part of the certification process, manufacturers 
electing this standard would not only have to notify the agency of the 
election but also demonstrate the derivation of the 2011 baseline 
CO2 emission level for the engine family. Manufacturers 
would also have to demonstrate that they have exhausted all credit 
opportunities.
Durability testing
    Another element of the current certification process is the 
requirement to complete durability testing to establish DFs. As 
previously mentioned, manufacturers are required to demonstrate that 
their engines comply with emission standards throughout the regulatory 
compliance period of the engine. This demonstration is commonly made 
through the combination of low-hour test results and testing based 
deterioration factors.
    For engines without aftertreatment devices, deterioration factors 
primarily account for engine wear as service is accumulated. This 
commonly includes wear of valves, valve seats, and piston rings, all of 
which reduce in-cylinder pressure. Oil control seals and gaskets also 
deteriorate with age, leading to higher lubricating oil consumption. 
Additionally, flow properties of EGR systems may change as deposits 
accumulate and therefore alter the mass of EGR inducted into the 
combustion chamber. These factors, amongst others, may serve to reduce 
power, increase fuel consumption, and change combustion properties; all 
of which affect pollutant emissions.
    For engines equipped with aftertreatment devices, DFs take into 
account engine deterioration, as described above, in addition to aging 
affects on the aftertreatment devices. Oxidation catalysts and other 
catalytic devices rely on active precious metals to effectively convert 
and reduce harmful pollutants. These metals may become less active with 
age and therefore pollutant conversion efficiencies may decrease. 
Particulate filters may also experience reduced trapping efficiency 
with age due to ash accumulation and/or degradation of the filter 
substrate, which may lead to higher tailpipe PM measurements and/or 
increased regeneration frequency. If a pollutant is predominantly 
controlled by aftertreatment, deterioration of emission control depends 
on the continued operation of the aftertreatment device much more so 
than on consistent engine-out emissions.
    At this time, we anticipate that most engine component wear will 
not have a significant negative impact on CO2 emissions. 
However, wear and aging of aftertreatment devices may or may not have a 
significant negative impact on CO2 emissions. In addition, 
future engine or aftertreatment technologies may experience significant 
deterioration in CO2 emissions performance over the useful 
life of the engine. For these reasons, we believe that the use of DFs 
for CO2 emissions is both appropriate and necessary. As with 
criteria pollutant emissions, these DFs are preferably developed 
through testing the engine over a representative duty cycle for an 
extended period of time. This is typically either half or full useful 
life, depending on the regulatory category. The DFs are then calculated 
by comparing the high-hour to low-hour emission levels, either by 
division or subtraction (for multiplicative & additive DFs, 
respectively).
    This testing process may be a significant cost to an engine 
manufacturer, mainly due to the amount of time and resources required 
to run the engine out to half or full useful life. For this reason, 
durability testing for the determination of DFs is not commonly 
repeated from model year to model year. In addition, some DFs may be 
allowed to carry over between families sharing a common architecture 
and aftertreatment system. EPA prefers to have manufacturers develop 
testing-based DFs for their products. However, we do understand that 
for the reasons stated above, it may be impractical to expect 
manufacturers to have testing-based deterioration factors available for 
these final rules. Therefore, we are allowing manufacturers to use EPA-
assigned DFs for CO2. However, we also understand that 
CO2 is traditionally measured as

[[Page 57267]]

part of normal engine dynamometer testing. Therefore, we are requiring 
that manufacturers include CO2 data over their criteria 
pollutant durability demonstrations (if available), which will aid the 
agency in developing more accurate assigned DFs. This action is being 
taken in the context of engine manufacturers' concerns regarding the 
impact of deterioration of emissions components relative to the GHG 
standards. Engine manufacturers commented that there would be no 
deterioration of components used to reduce GHG emissions in Phase 1. As 
part of the Clean Air Act responsibility to demonstrate compliance 
throughout the useful life, manufacturer will need to provide data 
already collected during traditional criteria pollutant testing for 
full useful life performance.
IRAFs/Regeneration Impacts on CO2
    Heavy-duty engines may be equipped with exhaust aftertreatment 
devices which require periodic ``regeneration'' to return the device to 
a nominal state. A common example is a diesel particulate filter, which 
accumulates PM as the engine is operated. When the PM accumulation 
reaches a threshold such that exhaust backpressure is significantly 
increased, exhaust temperature is actively increased to oxidize the 
stored PM. The increase in exhaust temperature is commonly facilitated 
through late combustion phasing and/or raw fuel injection into the 
exhaust system upstream of the filter. Both methods impact emissions 
and therefore must be accounted for at the time of certification. In 
accordance with Sec.  86.004-28(i), this type of event would be 
considered infrequent because in most cases they only occur once every 
30 to 50 hours of engine operation (rather than once per transient test 
cycle), and therefore adjustment factors must be applied at 
certification to account for these effects.
    Similar to DFs, these adjustment factors are based off of 
manufacturer testing; however this testing is far less time consuming. 
Emission results are measured from two test cycles: With and without 
regeneration occurring. The differences in emission results are used, 
along with the frequency at which regeneration is expected to occur, to 
develop upward and downward adjustment factors. Upward adjustment 
factors are added to all emission results derived from a test cycle in 
which regeneration did not occur. Similarly, downward adjustment 
factors are subtracted from results based on a cycle which did 
experience a regeneration event. Each pollutant will have a unique set 
of adjustment factors and additionally, separate factors are commonly 
developed for transient and steady-state test cycles.
    The impact of regeneration events on criteria pollutants varies by 
pollutant and the aftertreatment device(s) used. In general, the 
adjustment factor can have a very significant impact on compliance with 
the NOX standard. For this reason, heavy-duty vehicle and 
engine manufacturers are already very well motivated to extend the 
regeneration frequency to as long an interval as possible and to reduce 
the duration of the regeneration as much as possible. Both of these 
actions significantly reduce the impact of regeneration on 
CO2 emissions and fuel consumption. We do not believe that 
adding an adjustment factor for infrequent regeneration to the 
CO2 or fuel efficiency standards would provide a significant 
additional motivation for manufacturers to reduce regenerations. 
Moreover, doing so would add significant and unnecessary uncertainty to 
our projections of CO2 and fuel consumption performance in 
2014 and beyond. In addressing that uncertainty, the agencies would 
have to set less stringent fuel efficiency and CO2 standards 
for heavy-duty trucks and engines. Therefore, we are not requiring the 
use of infrequent regeneration adjustment factors for CO2 or 
fuel efficiency in this program. This is consistent with comments 
received from engine manufacturers.
Auxiliary Emission Control Devices
    As part of the engine control strategy, there may be devices or 
algorithms which reduce the effectiveness of emission control systems 
under certain limited circumstances. These strategies are referred to 
as Auxiliary Emission Control Devices (AECDs). One example would be the 
reduced use of EGR during cold engine operation. In this case, low 
coolant temperatures may cause the electronic control unit to reduce 
EGR flow to improve combustion stability. Once the engine warms up, 
normal EGR rates are resumed and full NOX control is 
achieved.
    At the time of certification, manufacturers are required to 
disclose all AECDs and provide a full explanation of when the AECD is 
active, which sensor inputs effect AECD activation, and what aspect of 
the emission control system is affected by the AECD. Manufacturers are 
further required to attest that their AECDs are not ``defeat-devices,'' 
which are intentionally targeted at reducing emission control 
effectiveness.
    Several common AECDs disclosed for criteria pollutant certification 
will have a similarly negative influence on GHG emissions as well. One 
such example is cold-start enrichment, which provides additional 
fueling to stabilize combustion shortly after initially starting the 
engine. From a criteria pollutant perspective, HC emissions can 
reasonably be expected to increase as a result. From a GHG perspective, 
the extra fuel does not result in a similar increase in power output 
and therefore the efficiency of the engine is reduced, which has a 
negative impact on CO2 emissions. In addition, there may be 
AECDs that uniquely reduce GHG emission control effectiveness. 
Therefore, consistent with today's certification procedures, we are 
finalizing that a comprehensive list of AECDs covering both criteria 
pollutant, as well as GHG emissions is required at the time of 
certification.
(ii) EPA's N2O and CH4 Standards
    In 2009, EPA issued rules requiring manufacturers of mobile-source 
engines to report the emissions of CO2, N2O, and 
CH4 (74 FR 56260, October 30, 2009). Although CO2 
is commonly measured during certification testing, CH4 and 
N2O are not. CH4 has traditionally not been 
included in criteria pollutant regulations because it is a relatively 
stable molecule and does not contribute significantly to ground-level 
ozone formation. In addition, N2O is commonly a byproduct of 
lean-NOX aftertreatment systems. Until recently, these types 
of systems were not widely used on heavy-duty engines and therefore 
N2O emissions were insignificant. As noted in section II 
above, both species, while emitted in small quantities relative to 
CO2, have much higher global warming potential than 
CO2 and therefore must be considered as part of a 
comprehensive GHG regulation.
    EPA is requiring that CH4 and N2O be reported 
at the time of certification, however we will allow manufacturers to 
submit a compliance statement based on good engineering judgment for 
the first year of the program in lieu of direct measurement of 
N2O. However, beginning in the 2015 model year, the agency 
is requiring the direct measurement of N2O for 
certification. The intent of the CH4 and N2O 
standards are more focused on prevention of future increases in these 
compounds, rather than forcing technologies that reduce these 
pollutants. As one example, we envision manufacturers satisfying this 
requirement by continuing to use catalyst designs and formulations that 
appropriately control N2O emissions rather than pursuing a 
catalyst that may

[[Page 57268]]

increase N2O. In many ways this becomes a design-based 
criterion in that the decision of one catalyst over another will 
effectively determine compliance with N2O standards over the 
useful life of the engine. As discussed above, in cases where 
N2O emissions directly tradeoff with CO2 
emissions, EPA is allowing manufacturers to exploit this relationship 
to produce engines with the lowest overall GHG emissions. Direct 
measurement of N2O emissions is required in the case of 
engines utilizing this temporary credit program.
    Since catalytic activity generally changes with age and service 
accumulation, it is not unreasonable to expect changes in 
N2O and CH4 emissions over the useful life of the 
engine. We also believe that low-hour test results coupled with 
deterioration factors provides an adequate representation of end-of-
life emission levels for these pollutants. However, the requirement to 
measure N2O and CH4 during testing is relatively 
new and we do not expect that manufacturers have consistent durability 
data to formulate deterioration factors for today's action. We also do 
not believe it is appropriate to require all new durability testing to 
satisfy this requirement, as this would result in a nontrivial burden 
to engine manufacturers. Instead we will be assigning deterioration 
factors for N2O and CH4 for this action. If the 
use of assigned deterioration factors jeopardizes compliance with the 
emission standards, we will also allow manufacturers to propose unique 
testing-based deterioration factors for these pollutants. In response 
to comments received from engine manufacturers regarding the timing 
needed to generate deterioration factors the agencies are taking this 
approach.
    Concerns had also been raised by engine manufacturers regarding 
measurement techniques for quantifying N2O emissions. In an 
effort to expand testing options, we are adding an allowance to use 
laser infrared analyzers for N2O measurement in 40 CFR part 
1065.275. This is to reflect the recent development of this technology 
for N2O measurement. We would also like to serve notice that 
in an upcoming rulemaking, we will be tightening the interference 
tolerance (both positive and negative) for engines and vehicles that 
are required to certify to an N2O standard. This will 
consist of an interference limit based on interference as a percentage 
of the flow weighted mean concentration of N2O expected at 
the standard. For example we may set the interference limit at 10 percent of the flow weighted mean concentration of 
N2O expected at the standard and strongly recommend a lower 
interference that is within 5 percent.
(c) Additional Compliance Provisions
(i) Warranty & Defect Reporting
    Under section 207 of the CAA, engine manufacturers are required to 
warrant that their product is free from defects that would cause the 
engine to not comply with emission standards. This warranty must be 
applicable from when the engine is introduced into commerce through a 
period generally defined as half of the regulatory useful life 
(specified in hours and years, whichever comes first). The exact time 
of this warranty is dependent on the regulatory category of the engine. 
In addition, components that are considered ``high cost'' are required 
to have an extended warranty. Examples of such components would be 
exhaust aftertreatment devices and electronic control units.
    Current warranty provisions in 40 CFR part 86 define the warranty 
periods and covered components for heavy-duty engines. The current list 
of components is comprised of any device or system whose failure would 
result in an increase in criteria pollutant emissions. We remain 
convinced that this list is adequate for addressing GHG emissions as 
well, based on comments received from the proposed rules. The following 
list identifies items commonly defined as critical emission-related 
components:

 Electronic control units.
 Aftertreatment devices.
 Fuel metering components.
 EGR-System components.
 Crankcase-ventilation valves.
 All components related to charge-air compression and cooling.
All sensors and actuators associated with any of these components.

    When a manufacturer experiences an elevated rate of failure of an 
emission control device, they are required to submit defect reports to 
the EPA. These reports will generally have an explanation of what is 
failing, the rate of failure, and any possible corrections taken by the 
manufacturer. Based on how successful EPA believes the manufacturer to 
be in addressing these failures, the manufacturer may need to conduct a 
product recall. In such an instance, the manufacturer is responsible 
for contacting all customers with affected units and repairing the 
defect at no cost to them. We believe this structure for the reporting 
of criteria pollutant defects, and recalls, is appropriate for 
components related to complying with GHG emissions as well.
(ii) Maintenance
    Engine manufacturers are required to outline maintenance schedules 
that ensure their product will remain in compliance with emission 
standards throughout the useful life of the engine. This schedule is 
required to be submitted as part of the application for certification. 
Maintenance that is deemed to be critical to ensuring compliance with 
emission standards is classified as ``critical emission-related 
maintenance.'' Generally, manufacturers are discouraged from specifying 
that critical emission-related maintenance is needed within the 
regulatory useful life of the engine. However, if such maintenance is 
unavoidable, manufacturers must have a reasonable basis for ensuring it 
is performed at the correct time. This may be demonstrated through 
several methods including survey data indicating that at least 80 
percent of engines receive the required maintenance in-use or 
manufacturers may provide the maintenance at no charge to the user. 
During durability testing of the engine, manufacturers are required to 
follow their specified maintenance schedule.
    Maintenance relating to components relating to reduction of GHG 
emissions is not expected to present unique challenges. Therefore, we 
are not finalizing any changes to the provisions for the specification 
of emission-related maintenance as outlined in 40 CFR part 86.
(2) Enforcement Provisions
(a) Emission Control Information Labels
    Current provisions for engine certification require manufacturers 
to equip their product with permanent emission control information 
labels. These labels list important characteristics, parameters, and 
specifications related to the emissions performance of the engine. 
These include, but are not limited to, the manufacturer, model, 
displacement, emission control systems, and tune-up specifications. In 
addition, this label also provides a means for identifying the engine 
family name, which can then be referenced back to certification 
documents. This label provides essential information for field 
inspectors to determine that an engine is in fact in the certified 
configuration.
    We do not anticipate any major changes needing to be made to 
emission control information labels as a result of new GHG standards 
and a single label is appropriate for both criteria pollutant and GHG 
emissions purposes. Perhaps the most significant addition will be the 
inclusion of Family Certification Levels or Family Emission Limits for 
GHG pollutants, if the manufacturer is participating in averaging, 
banking, and

[[Page 57269]]

trading. In addition, the label will need to indicate whether the 
engine is certified for use in vocational vehicles, tractors, or both. 
Finally, if an engine family is uniquely certified for use in hybrid 
powertrain applications, a compliance statement indicating this will 
need to be included on the emission control label.
    In response to comments from engine and truck manufacturers that 
tractors should be allowed to obtain engines certified for vocational 
use and likewise a limited number of engines certified for tractor use 
should be available for the appropriate vocational applications, the 
agencies are allowing limited use of engines certified in other 
categories. To address compliance needs and to discourage abuse of the 
provisions, proper labeling of the engines is essential.
(b) In-Use Standards
    In-use testing of engines provides a number of benefits for 
ensuring useful life compliance. In addition to verifying compliance 
with emission standards at any given point in the useful life, it can 
be used along with manufacturer defect reporting, to indentify 
components failing at a higher than normal rate. In this case, a 
product recall or other service campaign can be initiated and the 
problem can be rectified. Another key benefit of in-use testing is the 
discouragement of control strategies catered to the certification test 
cycles. In the past, engine manufacturers were found to be producing 
engines that performed acceptably over the certification test cycle, 
while changing to alternate operating strategies ``off-cycle'' which 
caused increases in criteria pollutant emissions. While these 
strategies are clearly considered defeat devices, in-use testing 
provides a meaningful way of ensuring that such strategies are not 
active under normal engine operation.
    Currently, manufacturers of certified heavy-duty engines are 
required to conduct in-use testing programs. The intent of these 
programs is to ensure that their products are continuing to meet 
criteria pollutant emission standards at various points within the 
useful life of the engine. Since initial certification is based on 
engine dynamometer testing, and removing in-use engines from their 
respective vehicles is often impractical, a unique testing procedure 
was developed. This includes using portable emission measurement 
systems (PEMS) and testing the engine over typical in-situ drive routes 
rather than a prescribed test cycle. To assess compliance, emission 
results from a well defined area of the speed/torque map of the engine, 
known as the NTE zone, are compared to the emission standards. To 
account for potential increases in measurement and operational 
variability, certain allowances are applied to the standard which 
results in the standard for NTE measurements (NTE limit) to be at or 
above the duty cycle emission standards.
    In addition, EPA conducts an annual in-use testing program of 
heavy-duty engines. Testing procured vehicles with specific engines 
over well-defined drive routes using a constant trailer load allows for 
a consistent comparison of in-use emissions performance. If potential 
problems are identified in-situ, the engine may be removed from the 
vehicle and tested using an engine dynamometer over the certification 
test cycles. If deficiencies are confirmed the agency will either work 
with the manufacturer to take corrective action, possibly involving a 
product recall, or proceed with enforcement action against the 
manufacturer.
    The GHG reporting rule requires manufacturers to submit 
CO2 data from all engine testing (beginning in the 2011 
model year), which we believe is equally applicable to in-use 
measurements. Methods of CO2 in-situ measurement are well 
established and most, if not all, PEMS devices measure and record 
CO2 along with criteria pollutants. CH4 and 
N2O present in-situ measurement challenges that may be 
impractical to overcome for this testing, and therefore they are not 
included in in-use testing requirements at this time. While measurement 
of CO2 may be practical and important, implementing an NTE 
emission standard for CO2 is challenging. As previously 
discussed, CO2 emissions are highly dependent on the drive 
cycle of the vehicle, which does not lend itself well to the NTE-based 
test procedure. Therefore, we proposed and are adopting that 
manufacturers be required to submit CO2 data from in-situ 
testing, in both g/bhp-hr and g/ton-mile, but these data will be used 
for reference purposes only (there would be no NTE limit/standard for 
CO2). For the purposes of calculating the g/ton-mile metric, 
we prefer that manufacturers use the measured vehicle weight. However 
it has been brought to our attention that this may not always be 
available, in which case an estimated vehicle weight can be used along 
with a written justification for the basis of the estimation. For 
engine-based (dynamometer) in-use testing, compliance with 
CO2 emission standards will be judged off of the FCL of the 
engine family.
(3) Other Certification Provisions
(a) Carryover/Carry Across Certification Test Data
    EPA's current certification program for heavy-duty engines allows 
manufacturers to carry certification test data over and across 
certification testing from one model year to the next, when no 
significant changes to models are made. EPA will also apply this policy 
to CO2, N2O and CH4 certification test 
data.
(b) Certification Fees
    The CAA allows EPA to collect fees to cover the costs of issuing 
certificates of conformity for the classes of engines covered by this 
rulemaking. On May 11, 2004, EPA updated its fees regulation based on a 
study of the costs associated with its motor vehicle and engine 
compliance program (69 FR 51402). At the time that cost study was 
conducted, the current rulemaking was not considered. At this time the 
extent of any added costs to EPA as a result of this program is not 
known. EPA will assess its compliance testing and other activities 
associated with the rules and may amend its fees regulations in the 
future to include any justifiable new costs.
(c) Onboard Diagnostics
(a) Onboard Diagnostics
    Beginning with the 2010 model year, manufacturers have been phasing 
in on-board diagnostic (OBD) systems on heavy-duty engines pursuant to 
the heavy-duty OBD rulemaking finalized by the EPA in 2009.\313\ These 
systems monitor the activity of the emission control system and issue 
alerts when faults are detected. These diagnostic systems are currently 
being developed based around components and systems that influence 
criteria pollutant emissions. Consistent with the light-duty 2012-2016 
MY vehicle rulemaking, we believe that monitoring of these components 
and systems for criteria pollutant emissions will have an equally 
beneficial effect on CO2 emissions.\314\ Therefore, we have 
not finalized any additional unique onboard diagnostic provisions for 
heavy-duty GHG emissions. In the NPRM, EPA did

[[Page 57270]]

not propose new or different diagnostic requirements from those 
finalized in the 2009 heavy-duty OBD rule.
---------------------------------------------------------------------------

    \313\ U.S. EPA, ``Control of Air Pollution from New Motor 
Vehicles and New Motor Vehicles Engines; Final Rule Regulations 
Requiring Onboard Diagnostic Systems on 2010 and Later Heavy-Duty 
Engines Used in Highway Applications Over 14,000 Pounds; Revisions 
to Onboard Diagnostic Requirements for Diesel Highway Heavy-Duty 
Vehicles Under 14,000 Pounds,'' published February 24, 2009. 
Available here: http://www.epa.gov/otaq/regs/im/obd/regtech/hd-obd-frm-02-24-09-notice-74-fr-8310.pdf.
    \314\ See the Light-Duty 2012-2016 Vehicle Rule, Note 5, above.
---------------------------------------------------------------------------

    The agencies received comments from engine manufacturers, hybrid 
system manufacturers, and related trade groups which broached concerns 
regarding the feasibility of applying on-board diagnostics to hybrid 
applications starting in 2013. The commenters stated that engine 
manufacturers would need several years to adapt their engine OBD 
systems to hybrids, and therefore requested a delay of OBD requirements 
for hybrid applications until 2020 with a phase-in of enforcement 
liability starting that same year. Details, which the agencies believe 
have merit, are set out below. In response, EPA is taking an approach 
that is consistent with certain provisions of the existing final action 
for heavy-duty OBD, finalized in 2009. To that end, manufacturers who 
certify hybrid systems will continue to have the responsibility of 
implementing compliant diagnostic systems, however, we are extending 
the OBD phase-in for engines with hybrid systems to allow time for 
manufacturers to be able to address communication protocol development 
concerns (e.g. SAE J1939, communication with diagnostic scantools), 
component development concerns (e.g. hardware and software), and to 
address the availability of heavy-duty OBD compliant engines with 
sufficient lead-time for additional hybrid diagnostic system 
development given resource constraints as engine manufacturers are 
focused on meeting the 2013 requirements for conventional products at 
this time.
    Since publication of the NPRM, the EPA has undertaken extensive 
outreach to hybrid manufacturers, engine manufacturers, and related 
industry groups to further understand the technical issues involved 
with the implementation of full OBD on engine-hybrid systems.\315\ 
Hybrid manufacturers have indicated that the interaction between hybrid 
systems and OBD compliant engines is not well understood at this time, 
for example, if the system shuts down the vehicle at idle (as is 
common), the OBD idle diagnostics cannot run. In addition, there are 
many different hybrid systems being developed which make much of this 
technology both immature and low volume, and engine manufacturers are 
concerned that this will result in high costs due to frequent design 
changes that could occur as this technology develops and have asked for 
flexibility for unique hybrid applications. Consistent with the goal to 
incentivize the development of hybrid designs (systems designed to 
capture wasted energy and reduce fuel consumption) the EPA is allowing 
hybrid manufacturers time to develop their systems while simultaneously 
developing the capability to meet HD OBD requirements.
---------------------------------------------------------------------------

    \315\ See EPA Docket EPA-HQ-OAR-2010-0162 for memos describing 
meetings held as a part of this outreach.
---------------------------------------------------------------------------

    Communication protocol development is an integral part of 
developing hybrid OBD capability for the heavy-duty industry which is 
not vertically integrated. There are different protocols required to be 
used for OBD communication in a vehicle depending on the type of engine 
(gasoline or diesel). These protocols are developed in part to 
standardize the transmission of electronic signals and control 
information among vehicle components. The J1939 communication protocol 
is developed by committee through SAE and is required for use with 
diesel engines. J1939 defines communications messages, diagnostic 
messages for communications between a module and diagnostic scantool, 
and fault codes. Messages sent through a J1939 network contain a series 
of information (e.g. an identifier, message priority, data, etc.) and 
these parameters must be agreed upon through the SAE committee and 
tailored to work for all manufacturers. The development of this 
communication protocol includes developing criteria for the messages, 
and determining a single set of fault codes that can work for all 
manufacturers and all hybrid system configurations; this is expected to 
take a substantial amount of time and collaboration. OBD cannot exist 
without fault codes to report, therefore development of this protocol 
is critical. Hybrid manufacturers have stated that until such time as a 
`plug and play scheme' is available, hybrid volumes will not be able to 
increase significantly. At this time, there are only a few such 
messages that have been developed for use in hybrid systems, and there 
is much additional development that needs to take place. The type of 
messages needed must first be identified once 2013 HD OBD compliant 
engines are available for use in HD hybrid OBD system development. 
After needed messages are identified, the content of each message must 
be developed and agreed upon through a ballot process. Manufacturers 
have stated that this will be an iterative process and will likely take 
at least two years to develop the protocol for use with different 
variations of hybrid systems and architectures, different types of 
energy storage systems, and for systems used in the wide variety of 
applications in the heavy-duty market, and we agree with this 
assessment. While a level of communication exists today between engines 
and transmissions for this industry, the level of control and impact on 
engine system operation becomes much more significant once hybrid 
technology is introduced. The purpose of the hybrid energy system is to 
supplement overall vehicle power demands. As such, the methods used for 
integrating the energy from the hybrid system into overall vehicle 
operation vary from allowing additional internal combustion engine 
lower power operation to potentially decreasing the amount of engine 
``on'' time. This range of performance impacts will serve to reduce GHG 
emissions by reducing demands on the engine. Conventional transmission 
systems and other powertrain components do not exercise the level of 
control the hybrid will need to exercise to effectively reduce GHG 
emissions and improve fuel consumption performance for internal 
combustion engines; therefore, hybrid OBD systems can reasonably be 
expected to be more complicated as well.
    Component development concerns raised by hybrid manufacturers 
include both changes that may be required to software and/or hardware 
systems on both existing hybrid products and on hybrid systems 
currently under development. Software systems in existing products have 
been developed that provide proprietary diagnostic capability (as no 
standardized system such as J1939 had been developed for these 
systems), however, these software systems are not OBD compliant. These 
products will likely require entirely new software systems developed 
for them which may result in hardware changes as well. Manufacturers 
have stated that a complete software system can take up to 2 years to 
develop and validate. Hardware may also need to be changed to 
accommodate OBD on hybrid systems. In particular, hardware changes 
would affect current production systems which may not have controllers 
that can support full OBD. The low volume sales and high cost of a 
controller program (which can reach into the millions of dollars) means 
that most companies cannot justify the cost of a hardware change for 
hybrids alone, rather, existing hybrid systems will have to wait until 
such a hardware upgrade is planned for other reasons. In addition, new 
hardware programs, such as developing a new Electronic Control Unit, 
can take 3-4 years to complete.

[[Page 57271]]

While it is possible for some of this work to be done concurrently, how 
much can be done this way is dependent on the configuration of each 
individual system. Finally, manufacturers may have contractual 
agreements with hardware and software suppliers that will have to be 
reconfigured to address a complete OBD program.
    Hybrid manufacturers have stated that they will be unable to 
produce hybrid systems that will be OBD compliant in 2013. Given the 
concerns discussed above and the general lack of availability of OBD 
compliant engines until the completion of the HD OBD phase-in, to 
require manufacturers of systems that depend on the availability of 
those OBD complaint engines to then be able to immediately implement 
additional requirements may be impractical or infeasible in many 
instances. Given the phase-in of HD OBD requirements that already 
exists however, we do not believe a delay to 2019 or 2020 is warranted. 
While not all of the engines that would potentially have hybrid systems 
incorporated into their design are available in their final OBD 
configuration at the time of this action, it is clear that some engine 
systems will be available. Additionally, there is an expectation that 
engine manufacturers, their suppliers and customers will have to 
continue to work cooperatively to deliver products for the market. This 
cooperation must include a level of concurrent engineering prior to 
products being brought to market. At this time we believe a delay to 
2016 for the phase-in of OBD for heavy-duty engines equipped with 
hybrid systems should provide the requisite lead time from the date of 
this action to the date of implementation for development of components 
and protocols necessary for successful integration of complete OBD 
systems for engines equipped with hybrid systems.
    Manufacturers will be required to implement feasible controls for 
these hybrid systems that do not adversely impact emissions performance 
in 2013 and by 2016-17, all systems must be fully compliant with OBD 
requirements. The phase in period takes into account that current 
production systems are likely to be smaller in terms of sales volumes 
than newly developed systems, and may require more hardware and 
software development as some of these systems have been in production 
for nearly a decade and have developed a proprietary system diagnostic 
capability that does not meet OBD requirements. Therefore, this 
extended phase-in provides them an additional year of time to comply 
with the heavy-duty OBD regulations. Hybrid systems put into production 
after January 1, 2013 will be required to meet the 2009 heavy-duty OBD 
requirements in 2016 consistent with the next phase-in date for heavy-
duty OBD, while those hybrid systems released prior to January 1, 2013 
have until 2017 to be compliant with these OBD requirements.
    If a manufacturer certifies an engine-hybrid system with CARB OBD 
in California prior to the required phase-in date (2016 or 2017), and 
its diagnostics meet or exceed the requirements for full 2013 OBD, the 
manufacturer must either use the CARB certified package for Federal 
release or phase in the package and certify it with full EPA OBD.
    In the interim, engine system diagnostics must show that they meet 
or exceed CARB's Engine Manufacturer Diagnostic Systems Requirements 
(EMD) including system monitoring requirements for NOX 
aftertreatment, fuel systems, exhaust gas recirculation, particulate 
matter traps, and emission-related electronic components.\316\ Specific 
EMD requirements will be considered met if they are redundant due to 
the installed engine's fully functioning OBD content. Most 
manufacturers have already certified their engines with EMD for the 
2011 model year, and full OBD as required in 2013 exceeds EMD 
requirements, therefore no new cost burden is expected as a result of 
this provision. In addition, new engines may be introduced in 2013 for 
hybrid-only use and, in lieu of meeting full OBD, meeting EMD would 
result in cost savings because of the flexibility in scan-tool 
reporting and diagnostic content.
---------------------------------------------------------------------------

    \316\ California Air Resources Board, Final Regulation Order for 
EMD, Section 1971 of Title 13, California Code of Regulations, 
effective December 30, 2004. Available here; http://www.arb.ca.gov/regact/emd2004/fro.pdf.
---------------------------------------------------------------------------

    In addition, the engine-hybrid system must maintain existing OBD 
capability for engines where the same or equivalent engine (e.g. 
displacement) has been OBD certified. An equivalent engine is one 
produced by the same engine manufacturer with the same fundamental 
design, but that may have no more than minor hardware or calibration 
differences, such as slightly different displacement, rated power, or 
fuel system. Though the OBD capability must be maintained, it does not 
have to meet detection thresholds and in-use performance frequency 
requirements; for example, a manufacturer may modify detection 
thresholds to prevent false detection.
    As stated earlier, existing hybrid systems sold today have 
proprietary diagnostic capability that is non-OBD compliant, but 
nonetheless will notify the driver of potential problems with the 
system. Hybrid manufacturers must also continue to maintain this 
existing diagnostic capability to ensure proper function consistent 
with the performance for which the hybrid system is certified as well 
as, safe operation of the hybrid system.
    Finally, during the interim part of the phase-in, manufacturers 
that are not fully-OBD compliant must also submit an annual pre-
compliance report to the EPA for model years 2013 and later. The engine 
manufacturers must submit this report with their engine certification 
information. Hybrid manufacturers that are not certifying the engine-
hybrid systems must also submit an annual pre-compliance report to the 
EPA. The report must include a description of the engine-hybrid system 
being certified and related product plans, information as to activities 
undertaken and progress made by the manufacturer in achieving full OBD 
certification including monitoring, diagnostics, and standardization; 
and deviations from an originally certified full-OBD package with 
engineering justification.
(d) Applicability of Current High Altitude Provisions to Greenhouse 
Gases
    EPA is requiring that engines covered by this program must meet 
CO2, N2O and CH4 standards at elevated 
altitudes. The CAA requires emission standards under section 202 for 
heavy-duty engines to apply at all altitudes. EPA does not expect 
engine CO2, CH4, or N2O emissions to 
be significantly different at high altitudes based on engine 
calibrations commonly used at all altitudes. Therefore, EPA will retain 
its current high altitude regulations so manufacturers will not 
normally be required to submit engine CO2 test data for high 
altitude. Instead, they will be required to submit an engineering 
evaluation indicating that common calibration approaches will be 
utilized at high altitude. Any deviation in emission control practices 
employed only at altitude will need to be included in the AECD 
descriptions submitted by manufacturers at certification. In addition, 
any AECD specific to high altitude will be required to include 
emissions data to allow EPA to evaluate and quantify any emission 
impact and validity of the AECD.
(e) Emission-Related Installation Instructions
    Engine manufacturers are currently required to provide detailed 
installation instructions to vehicle manufacturers.

[[Page 57272]]

These instructions outline how to properly install the engine, 
aftertreatment, and other supporting systems, such that the engine will 
operate in its certified configuration. At the time of certification, 
manufacturers may be required to submit these instructions to EPA to 
verify that sufficient detail has been provided to the vehicle 
manufacturer.
    We do not anticipate any major changes to this documentation as a 
result of regulating GHG emissions. The most significant impact will be 
the addition of language prohibiting vehicle manufacturers from 
installing engines into vehicle categories in which they are not 
certified for. An example would be a tractor manufacturer installing an 
engine certified for only vocational vehicle use. Explicit instructions 
on behalf of the engine manufacturer that such acts are prohibited will 
serve as sufficient notice to the vehicle manufacturers and failure to 
follow such instructions will result in the vehicle manufacturer being 
in non-compliance.
(f) Alternate CO2 Emission and Fuel Consumption Standards
    Under the final rules, engine manufacturers have the option of 
certifying to alternate CO2 emission and fuel consumption 
standards for model years 2014 through 2016. These alternate standards 
are defined as a certain percentage below a baseline value established 
from their corresponding 2011 model-year products. For instance, the 
alternate emission standard for light and medium heavy duty FTP-
certified (vocational) engines is equal to 0.975 times the baseline 
value. If a manufacturer elects to participate in this program it must 
indicate this on its certification application. In addition, sufficient 
details must be submitted regarding the baseline engine such that the 
agency can verify that the correct optional CO2 emission and 
fuel consumption standards have been calculated. These data will need 
to include the engine family name of the baseline engine, so references 
to the original certification application can be made, as well as test 
data showing the CO2 emissions and fuel consumption of the 
baseline engine.
(4) Compliance Reports
(a) Early Model Year Data
    NHTSA's regulatory text in the NPRM included specifications for 
manufacturers to submit pre-certification compliance reports for heavy-
duty engines. The pre-certification reports included requirements for 
manufacturers to submit information to identify the types of engines, 
expected test results, production volumes and credits. The reporting 
requirements were general in nature despite there being an existing 
emissions program for heavy-duty engines. The existing ABT program for 
NOX and PM emissions for heavy-duty engines has existed 
since 2001 (see 66 FR 5002 signed on January 18, 2001) but does not 
require reporting early model year compliance information. The agencies 
sought comments on the report provisions in the NPRM but commenters 
failed to offer recommendations on what content should be required. As 
a result, the agencies have decided to eliminate the pre-certification 
report because engine manufacturers have no experience in providing GHG 
information and the proposed information may not be available until 
subsequent model years. For the next phase of this GHG program, the 
agencies may adopt a pre-model year report for engines.
    As an alternative to receiving early compliance model year 
information in the precertification reports, the agencies have decided 
to use manufacturer's application for certificates of conformity to 
obtain early model estimates. Currently, the applications for 
certificates are not required to include the fuel consumption 
information required by NHTSA. Therefore, the agencies are adopting 
provisions in the final rules for manufacturers to provide emission and 
equivalent fuel consumption estimates in the manufacturer's 
applications for certification. The agencies will treat information 
submitted in the applications as a manufacturer's demonstration of 
providing early compliance information, similar to the pre-model year 
report submitted for heavy-duty pick-up trucks and vans. The final 
rules establish a harmonized approach by which manufacturers will 
submit applications through the EPA Verify database system as the 
single point of entry for all information required for this national 
program and both agencies will have access to the information. If by 
model year 2012, the agencies are not prepared to receive information 
through the EPA Verify database system, manufacturers are expected to 
submit written applications to the agencies. This approach should 
streamline this process and reduce industry burden and provide 
sufficient information for the agencies to carry out their early 
compliance activities.
(b) Final Reports
    For engines, the agencies proposed that manufacturers would submit 
EOY reports and final reports. An EOY report for manufacturers using 
the ABT program was required to be submitted no later than 90 days 
after the calendar year and final report no later than 270 days after 
the calendar year.\317\ Manufacturers not participating in the ABT 
program were required to provide an EOY report within 45 days after the 
calendar year but no final reports were required. The final ABT report 
due date was established coinciding with EPA's existing criteria 
pollutant report for heavy-duty engines complying with NOX 
and PM standards. Similar to that program, the proposed EOY and final 
reports required receiving engine type designation, engine family and 
credit plans for engine manufacturers.
---------------------------------------------------------------------------

    \317\ Corresponding to the compliance model year.
---------------------------------------------------------------------------

    There were no comments received on the final reports for engines. 
For the final rules, the agencies will retain the provisions as 
proposed for the EOY and final reports. However, the agencies will 
consolidate the reporting as done for other vehicle categories and will 
require emissions and equivalent fuel consumption information to be 
submitted to EPA. The final rules establish a harmonized approach by 
which manufacturers will submit applications to EPA as the single point 
of entry for all information required for this national program and 
both agencies will have access to the appropriate information. If by 
model year 2012, the agencies are not prepared to receive information 
through a database system, manufacturers are expected to submit written 
applications to the agencies. The agencies are also combining the EOY 
reports for manufacturers not using ABT to provide a product volume 
report due 90 days after the end of the model year and the ABT report 
required 90 days after the model year. A summary of the required 
information in the final rules for EOY and final reports is as follows:
     Engine family designation and averaging set.
     Engine emissions and fuel consumption standards including 
any alternative standards used.
     Engine family FCLs.
     Final production volumes.
     Certified test cycles.
     Useful life values for engine families.
     A credit plan identifying the manufacturers actual credit 
balances, credit flexibilities, credit trades and a credit deficit plan 
if needed demonstrating how it plans to resolve

[[Page 57273]]

any credit deficits that might occur for a model year within a period 
of up to three model years after that deficit has occurred.
(c) Additional Required Information
    Throughout the model year, manufacturers may be required to submit 
various reports to the agencies to comply with various aspects of the 
program. These reports have differing criteria for submission and 
approval.
    Table V-1 below provides a summary of the types of submission, 
required submission dates and the EPA and NHTSA regulations that apply 
for engines and engine manufacturers.
    The agencies will review and grant any appropriate requests 
considering the timeliness of the submissions and the completeness of 
the requests.

                       Table V-1--Summary of Required Information for HD Engine Compliance
----------------------------------------------------------------------------------------------------------------
                                                                                                       NHTSA
            Submission                    Applies to        Required submissions  EPA regulation    regulation
                                                                    date             reference       reference
----------------------------------------------------------------------------------------------------------------
Small business exemptions.........  Engine manufacturers   Before introducing               Sec.    Sec.   535.8
                                     meeting the Small      any excluded vehicle        1036.150
                                     Business               into U.S. for
                                     Administration (SBA)   commerce.
                                     size criteria of a
                                     small business as
                                     described in 13 CFR
                                     121.201.
Incentives for early introduction.  The provisions apply   EPA must be notified             Sec.    Sec.   535.8
                                     with respect to        before the                  1036.150
                                     tractors and           manufacturer submits
                                     vocational vehicles    it applications for
                                     produced in model      certificates of
                                     years before 2014.     conformity.
Voluntary compliance for NHTSA      Engine manufacturers   NHSAT must be                      NA    Sec.   535.8
 standards.                          seeking early          notified before the
                                     compliance in model    manufacturer submits
                                     years 2014 to 2016.    it applications for
                                                            certificates of
                                                            conformity.
Model year 2014 N2O standards.....  Manufacturers that     EPA must be notified             Sec.              NA
                                     choose to show         before the                  1036.150
                                     compliance with the    manufacturer submits
                                     MY 2014 N2O            it applications for
                                     standards requesting   certificates of
                                     to use an              conformity.
                                     engineering analysis.
Exemption from EOY reports........  Manufacturers with     90-days after the                Sec.    Sec.   535.8
                                     surplus credits at     calendar year ends.         1036.730
                                     the end of the model
                                     year.
Alternative engine standards......  Engine manufacturers   EPA and NHTSA must be            Sec.    Sec.   535.8
                                     not able to comply     notified before the         1036.150
                                     with 1036.104 and      manufacturer submits
                                     wanting to use the     it applications for
                                     alternative engine     certificates of
                                     standard.              conformity.
Alternate phase-in................  Engine manufacturers   EPA and NHTSA must be            Sec.    Sec.   535.8
                                     want to comply with    notified before the         1036.150
                                     alternate phase in     manufacturer submits
                                     standards.             it applications for
                                                            certificates of
                                                            conformity.
----------------------------------------------------------------------------------------------------------------

D. Class 7 and 8 Combination Tractors

(1) Compliance Approach
    In addition to requiring engine manufacturers to certify their 
engines, manufacturers of Class 7 and 8 combination tractors must also 
certify that their vehicles meet the CO2 emission and fuel 
consumption standards. This vehicle certification will ensure that 
efforts beyond just engine efficiency improvements are undertaken to 
reduce GHG emissions and fuel consumption. Some examples include 
aerodynamic improvements, rolling resistance reduction, idle reduction 
technologies, and vehicle speed limiting systems.
    Unlike engine certification however, this certification will be 
based on a load-specific basis (g/ton-mile or gal/1,000 ton-mile as 
opposed to work-based, or g/bhp-hr). This would take into account the 
anticipated vehicle loading that would be experienced in use and the 
associated affects on fuel consumption and CO2 emissions. 
Vehicle manufacturers will also be required to warrant their products 
against emission control system defects, and demonstrate that a service 
network is in place to correct any such conditions. The vehicle 
manufacturer also bears responsibility in the event that an emission-
related recall is necessary.
(a) Certification Process
    In order to obtain a certificate of conformity for the tractor, the 
tractor manufacturer will complete a compliance demonstration, showing 
that their product meets emission standards as well as other regulatory 
requirements. For purposes of this demonstration, vehicles with similar 
emission characteristics throughout their useful life are grouped 
together in vehicle families, which are defined primarily by the 
regulatory subclass of the vehicle. Manufacturers may further classify 
vehicles together into sub-families within a given vehicle family for a 
given regulatory subcategory. Examples of characteristics that would 
define a vehicle sub-family for heavy-duty vehicles are wheel and tire 
package, aerodynamic profile, tire rolling resistance, and vehicle 
speed limiting system. Compliance with the emission standards (or FEL) 
will be determined at the sub-family level.
    Under this system, the worst-case vehicle configuration would be 
selected based on having the highest fuel consumption, and all other 
configurations within the family or sub-family are assumed to have 
emissions and fuel consumption at or below the parent model and 
therefore in compliance with CO2 emission and fuel 
consumption standards. Any vehicle within the family can be subject to 
selective enforcement auditing in addition to confirmatory or other 
administrator testing.
    Vehicle families for Class 7 and 8 combination tractors will 
utilize the standardized 12-digit naming convention, as described along 
with the engine certification process in Section V.C.1.a, above. As 
with engines, each certifying vehicle manufacturer will have a unique 
three digit code assigned to them. Currently, there is no 5th digit 
(industry sector) code for this class of vehicles, for which we 
proposed to use the next available character, ``2.'' The agencies 
originally proposed that engine displacement be included in the vehicle

[[Page 57274]]

family name, however the wide range of engines available across most 
regulatory subcategories makes this requirement irrelevant and 
unnecessary at the time of this rulemaking. Therefore, we are reserving 
the remaining characters for California ARB and/or manufacturer use, 
such that the result is a unique vehicle family name.
    Class 7 and 8 tractors share several common traits, such as the 
trailer attachment provisions, number of wheels, and general 
construction. However, further inspection reveals key differences 
related to GHG emissions. Payloads hauled by Class 7 tractors are 
significantly less than Class 8 tractors. In addition, Class 8 vehicles 
may have provisions for hoteling (``sleeper cabs''), which results in 
an increase in size as well as the addition of comfort features like 
power and climate control for use while the truck is parked. Both 
segments may have various degrees of roof fairing to provide better 
aerodynamic matching to the trailer being pulled. This is a feature 
which can help reduce CO2 emissions significantly when 
properly matched to the trailer, but can also increase CO2 
emissions if improperly matched. Based on these differences, it is 
reasonable to expect differences in CO2 emissions, and 
therefore these properties form the basis for the final combination 
tractor regulatory subcategories.
    The various combinations of payload, cab size, and roof profile 
result in nine final regulatory subcategories for Class 7 and 8 
tractors. Class 7 tractors are divided into three regulatory 
subcategories: one for low, one for mid roof height profiles, and one 
for high roof profiles. The Class 7 tractors are subject to a 10 year, 
185,000 regulatory useful life. Class 8 tractors are split into six 
regulatory subcategories reflecting two cab sizes (day and sleeper) and 
three roof height profiles (low, mid, and high). All Class 8 tractors 
are subject to a 10 year, 435,000 mile regulatory useful life.
(b) Demonstrating Compliance With the Final Standards
(i) CO2 and Fuel Consumption Standards
    As discussed at proposal, although whole-vehicle certification may 
be ultimately desirable for these vehicles, it is essentially 
infeasible to require it now. See 75 FR at 74270-71. Most commenters 
agreed, as did the NAS Report. Accordingly, again consistent with the 
NAS Report, the agencies have developed a predictive model for 
demonstrating compliance with these initial standards for combination 
tractors. The agencies will continue to work toward improved methods 
for whole vehicle performance characterization, as suggested by some 
commenters.
Model
    Vehicle modeling will be conducted using the agencies' simulation 
model, the GEM, which is described in detail in Chapter 4 of the RIA 
with responses to comments in the Summary and Analysis of Comments 
Document Section 7. Basically, this model functions by defining a 
vehicle configuration and then exercises the model over various drive 
cycles. Several initialization files are needed to define a vehicle, 
which include mechanical attributes, control algorithms, and driver 
inputs. The majority of these inputs will be predetermined by EPA and 
NHTSA for the purposes of vehicle certification. The net results from 
the GEM are weighted CO2 emissions and fuel consumption 
values over the drive cycles. The CO2 emission result will 
be used for demonstrating compliance with vehicle CO2 
standards while the fuel consumption result will be used for 
demonstrating compliance with the fuel consumption standards.
    The vehicle manufacturer will be responsible for entering up to 
seven inputs relating to the GHG performance of a vehicle configuration 
although, depending on the regulatory category, fewer inputs may be 
required. These inputs include the regulatory category, coefficient of 
drag, steer tire rolling resistance, drive tire rolling resistance, 
vehicle speed limit, vehicle weight reduction, and idle reduction 
credit. For the GEM inputs relating to aerodynamics, the agencies have 
finalized lookup tables for frontal area and coefficient of drag based 
on typical performance levels across the industry. Manufacturers are 
responsible for assessing the aerodynamic performance of their vehicles 
through testing or a combination of testing and modeling. This test 
data is then used to select the most appropriate agency-defined bin for 
entry into the GEM.
    Tire rolling resistance is simply the measured rolling resistance 
of the tire in kg per metric ton as described in ISO 28580:2009. This 
measured value is expected to be the result of three repeat 
measurements of three different tires of a given design, giving a total 
of nine data points. It is the average of these nine results that will 
be entered into the GEM. Tire rolling resistance may be determined by 
either the vehicle or tire manufacturer. In the latter case, a signed 
statement from the tire manufacturer confirming testing was conducted 
in accordance with this part is required.
    As previously described, limiting vehicle speed can have a 
significant effect on fuel consumption and we believe that 
manufacturers should be recognized for including technology that 
facilitates these limits. Also as described, these vehicle speed 
limiters are not likely to be a simple device with a fixed top speed. 
``Soft top'' limits based on driver behavior and limit expiration dates 
(or mileage) are two of the most common scenarios. To properly assess 
the GHG and fuel consumption benefits in light of these features, we 
are defining the proper methodology for entering the vehicle speed 
limit into the GEM. This is based on an equation including terms for 
VSL expiration (expiration factor) and VSL soft-top (soft-top factor 
and soft-top VSL). The result will be an effective vehicle speed limit 
reflecting the expected mileage and time that the limit will be used 
for. Additional details regarding this equation and its derivation can 
be found in RIA Chapter 2.
    For vehicle weight reduction, the agencies are primarily addressing 
the reduction of weight and perhaps number of wheels. This reduction is 
assessed relative to a standard combination tractor configuration with 
dual-wide rear tires with conventional steel wheels. Manufacturers may 
elect to use single-wide tires/wheels and/or aluminum (or light-weight 
aluminum) wheels or other components to reduce the weight of their 
vehicles. The agencies have defined standard weight reduction levels 
associated with each weight reduction technology for entry into the 
GEM. These reductions are listed in pounds per component, so 
manufacturers will need to multiply this reduction by the number of 
affected components for their total weight reduction entry into the 
GEM.
    Manufacturers of sleeper cabs electing to limit idle time to 300 
seconds or less can claim a GHG benefit of 5 g/ton-mile and should be 
entered into the GEM as such. This benefit cannot be scaled to reflect 
shorter or longer allowed idle times, but can be scaled based upon 
expiration date.
    The agencies will utilize the appropriate engine map reflecting use 
of a certified engine in the truck (and will enter the same value even 
if an engine family is certified to the temporary percent reduction 
alternative standard, in order to evaluate vehicle performance 
independently of engine performance.) We believe this approach reduces 
the testing burden placed upon manufacturers, yet adequately assesses

[[Page 57275]]

improvements associated with select technologies. The model will be 
publicly available and will be found on EPA's Web site.
    The agencies reserve the right to independently evaluate the inputs 
to the model by way of Administrator testing to validate those model 
inputs. The agencies also reserve the right to evaluate vehicle 
performance using the inputs to the model provided by the manufacturer 
to confirm the performance of the system using GEM. This could include 
generating emissions results using the GEM and the inputs as provided 
by the manufacturer based on the agency's own runs. This could also 
include conducting comparable testing to verify the inputs provided by 
the manufacturer. In the event of such testing or evaluation, the 
Administrator's results become the official certification results, the 
exception being that the manufacturer may continue to use their data as 
initially submitted, provided it represents a worst-case condition over 
the Administrator's results.
    To better facilitate the entry of only the appropriate parameters, 
the agencies will provide a graphical user interface in the model for 
entering data specific to each vehicle. In addition, EPA will provide a 
template that facilitates batch processing of multiple vehicle 
configurations within a given family. It is expected that this template 
will be submitted to EPA as part of the certification process for each 
certified vehicle family or subfamily.
    For certification, the model will exercise the vehicle over three 
test cycles; one transient and two steady-state. For the transient 
test, we are using the heavy heavy-duty diesel truck (HHDDT) transient 
test cycle, which was developed by the California Air Resources Board 
and West Virginia University to evaluate heavy-duty vehicles. The 
transient mode simulates urban, start-stop driving, featuring 1.8 stops 
per mile over the 2.9 mile duration. The two steady state test points 
are reflective of the tendency for some of these vehicles to operate 
for extended periods at highway speeds. Based on data from the EPA's 
MOVES database, and common highway speed limits, we are finalizing 
these two points to be 55 and 65 mph.
    The model will predict the total emissions results from each 
configuration using the unique properties entered for each vehicle. 
These results are then normalized to the payload and distance covered, 
so as to yield a gram/ton-mile result, as well as a fuel consumption 
(gal/1,000 ton-mile) result for each test cycle. As with engine and 
vehicle testing, certification will be based on the worst-case 
configuration within a vehicle family.
    The results from all three tests are then combined using weighting 
factors, which reflect typical usage patterns. The typical usage 
characteristics of Class 7 and 8 tractors with day cabs differ 
significantly from Class 8 tractors with sleeper cabs. The trucks with 
day cabs tend to operate in more urban areas, have a limited travel 
range, and tend to return to a common depot at the end of each shift. 
Class 8 sleeper cabs, however, are typically used for long distance 
trips which consist of mostly highway driving in an effort to cover the 
highest mileage in the shortest time. For these reasons, we proposed 
that the cycles are weighted differently for these two groups of 
vehicles. For Class 7 and 8 trucks with day cabs, we propose weights of 
64%, 17%, and 19% (65 mph, 55 mph, and transient, resp.). For Class 8 
with sleeper cabs, the high speed cruise tendency results in final 
weights of 86%, 9%, and 5% (65 mph, 55 mph, and transient, 
respectively). These final, weighted emission results are compared to 
the emission standard to assess compliance. The agencies received 
comments regarding the duty cycles and the weighting factors used for 
assessing emissions compliance. In making final determination for the 
cycle weighting factors, the agencies considered those comments, as 
well as the agencies' own data in determining the final weighting 
factors and duty cycles to be used for determining emissions 
compliance. Demonstration of compliance is also available through the 
use of credits generated as part of the Averaging, Banking, and Trading 
Program (ABT) as described earlier in this Preamble. Additionally, 
compliance may be demonstrated through the use of a Vehicle Speed 
Limiter (VSL) and the application of the VSL is accounted for as 
another input to the GEM for assessing GHG and fuel consumption 
emissions performance.
Durability Testing
    As with engine certification, a manufacturer must provide evidence 
of compliance through the regulatory useful life of the vehicle. 
Factors influencing vehicle-level GHG performance over the life of the 
vehicle fall into two basic categories: vehicle attributes and 
maintenance items. Each category merits different treatment from the 
perspective of assessing useful life compliance, as each has varying 
degrees of manufacturer versus owner/operator responsibility.
    The category of vehicle attributes generally refers to aerodynamic 
features, such as fairings, side-skirts, air dams, air foils, etc., 
which are installed by the manufacturer to reduce aerodynamic drag on 
the vehicle. These features have a significant impact on GHG emissions 
and their emission reduction properties are assessed early in the 
useful life (at the time of certification). These features are expected 
to last the full life of the vehicle without becoming detached, 
cracked/broken, misaligned, or otherwise not in a state which provides 
the original GHG emissions reduction. In the absence of the 
aforementioned failure modes, the performance of these features is not 
expected to degrade over time and the benefit to reducing GHG emissions 
is expected to last for the life of the vehicle with no special 
maintenance requirements. To assess useful life compliance, we are 
following a design-based approach which will ensure that the 
manufacturer has robustly designed these features so they can 
reasonably be expected to last the useful life of the vehicle.
    The category of maintenance items refers to items that are 
replaced, renewed, cleaned, inspected, or otherwise addressed in the 
preventative maintenance schedule specified by the vehicle 
manufacturer. Replacement items that have a direct influence on GHG 
emissions are primarily tires and lubricants. Synthetic engine oil may 
be used by vehicle manufacturers to reduce the GHG emissions of their 
vehicles. Manufacturers may specify that these fluids be changed 
throughout the useful life of the vehicle. If this is the case, the 
manufacturer should have a reasonable basis that the owner/operator 
will use fluids having the same properties. This may be accomplished by 
requiring (in service documentation, labeling, etc.) that only these 
fluids can be used as replacements.
    If the vehicle remains in its original certified condition 
throughout its useful life, it is not believed that GHG emissions would 
increase as a result of service accumulation. This is based on the 
assumption that as components such as tires wear, the rolling 
resistance due to friction is likely to stay the same or decrease. With 
all other components remaining equal (tires, aerodynamics, etc), the 
overall drag force would stay the same or decrease, thus not 
significantly changing GHG emissions at the end of useful life. It is 
important to remember however, that this vehicle assessment does not 
take into account any engine-related wear affects, which may in fact 
increase GHG emissions over time. The agencies received comments from 
engine and tractor manufacturers requesting an assigned deterioration 
factor of zero for GHG

[[Page 57276]]

emissions. As discussed previously, the agencies will allow the use of 
an assigned deterioration factor of zero where appropriate in Phase 1, 
however this does not negate the responsibility of the manufacturer to 
ensure compliance with the emissions standards throughout the useful 
life.
    For the reasons explained above, we believe that for the first 
phase of this program, it is most important to ensure that the vehicle 
remain in its certified configuration throughout the useful life. This 
can most effectively be accomplished through engineering analysis and 
specific maintenance instructions provided by the vehicle manufacturer. 
The vehicle manufacturer would be primarily responsible for providing 
engineering analysis demonstrating that vehicle attributes will last 
for the full useful life of the vehicle. We anticipate this 
demonstration will show that components are constructed of sufficiently 
robust materials and design practices so as not to become dysfunctional 
under normal operating conditions. For instance, we expect aerodynamic 
fairings to be constructed of materials similar to that of the main 
body of the vehicle (fiberglass, steel, aluminum, etc) and have 
sufficient support and attachment mechanisms so as not to become 
detached or broken under normal, on-highway driving.
(ii) EPA's Air Conditioning Leakage Standards
    Heavy-duty vehicle air conditioning systems contribute to GHG 
emissions in two ways. First, operation of the air conditioning unit 
places an accessory load on the engine, which increases fuel 
consumption. Second, most modern refrigerants are HFC-based, which have 
significant global warming potential (GWP=1430). For heavy-duty 
vehicles, the load added by the air conditioning system is 
comparatively small compared to other power requirements of the 
vehicle. Therefore, we are not targeting any GHG reduction due to 
decreased air conditioning usage or higher efficiency A/C units for 
this final action. However, refrigerant leakage, even in very small 
quantities, can have significant adverse effects on GHG emissions.
    Refrigerant leakage is a concern for heavy-duty vehicles, similar 
to light-duty vehicles. To address this, EPA is finalizing a design-
based standard for reducing refrigerant leakage from heavy-duty pickups 
and vans and combination tractors. This standard is based off using the 
best practices for material selection and interface sealing, as 
outlined in SAE publication J2727. Based on design criteria in this 
publication, a leakage ``score'' can be assessed and an estimated 
annual leak rate can be made for the A/C system based on the 
refrigerant capacity. (There is no requirement for vocational vehicle 
AC leakage for reasons explained at 75 FR 74211.)
    At the time of certification, manufacturers will be required to 
outline the design of their system, including the specification of 
materials and construction methods. They will also need to supply the 
leakage score developed using SAE J2727 and the refrigerant volume of 
their system to determine the leakage rate per year. If the certifying 
manufacturer does not complete installation of the air conditioning 
unit, detailed instructions must be provided to the final installer who 
ensures that the A/C system is assembled to meet the low-leakage 
standards. These instructions will also need to be provided at the time 
of certification, and manufacturers must retain all records relating to 
auditing of the final assembler.
(c) In-Use Standards
    As previously addressed, the drive-cycle dependence of 
CO2 emissions makes NTE-based in-use testing impractical. In 
addition, we believe the reporting of CO2 data from the 
criteria pollutant in-use testing program will be helpful in future 
rulemaking efforts. For these reasons, we are not finalizing an NTE-
based in-use testing program for Class 7 and 8 combination tractors for 
this program.
    In the absence of NTE-based in-use testing, provisions are 
necessary for verifying that production vehicles are in the certified 
configuration, and remain so throughout the useful life. Perhaps the 
easiest method for doing this is to verify the presence of installed 
emission-related components. This would basically consist of a vehicle 
audit against what is claimed in the certification application. This 
includes verifying the presence of aerodynamic components, such as 
fairings, side-skirts, and gap-reducers. In addition, the presence of 
idle-reduction and speed limiting devices would be verified. The 
presence of LRR tires could be verified at the point of initial sale; 
however verification at other points throughout the useful life would 
be non-enforceable for the reasons mentioned previously.
    The category of wear items primarily relates to tires. It is 
expected that vehicle manufacturers will equip their trucks with LRR 
tires, as they may provide a reduction in GHG emissions. The tire 
replacement intervals for this class of vehicle is normally in the 
range of 50,000 to 100,000 miles, which means the owner/operator will 
be replacing the tires at several points within the useful life of the 
vehicle. We believe that as LRR tires become more common on new 
equipment, the aftermarket prices of these tires will also decrease. 
The primary barrier to the introduction of more fuel efficient tire 
designs into the truck market is the upfront costs of tire development 
and upfront capital costs for new production machinery (e.g., new tire 
molds). Once manufacturers have sunk these costs into new tire designs 
and production facilities in order to meet our vehicle standards, there 
is little barrier for bringing these better products into the 
replacement tire market as well. Our regulations will effectively force 
OEMs to make these investments in tire designs and, having done so, 
should lead to better tires not only for new vehicles but in the 
replacement tire market as well. Along with decreasing tire prices, the 
fuel savings realized through use of LRR tires will ideally provide 
enough incentive for owner/operators to continue purchasing these 
tires. Thus, the inventory modeling in this final action reflects the 
continued use of LRR tires through the life of the vehicle.
(2) Enforcement Provisions
    As identified above, a significant amount of vehicle-level GHG 
reduction is anticipated to come from the use of components 
specifically designed to reduce GHG emissions. Examples of such 
components include LRR tires, aerodynamic fairings, idle reduction 
systems, and vehicle speed limiters. At the time of certification, 
vehicle manufacturers will specify which components will be on their 
vehicle when introduced into commerce. Based on this list of installed 
components, GHG emissions performance of the vehicle will be assessed 
using the GEM, and compliance with the family (or subfamily) emissions 
limit will need to be shown. Given the ability of manufacturers to 
demonstrate compliance through the use of flexibility provisions, as 
previously described, that will be taken into account when assessing 
the performance for purposes of enforcement. Additionally, should 
enforcement action be necessary against systems certified using the 
flexibility provisions, credit balances generated through the use of 
the provisions may be reduced as a consequence of enforcement activity. 
As described in the in-use testing section, it is important to have the 
ability to determine if the vehicle is in the certified configuration 
at the time of sale.

[[Page 57277]]

    Perhaps the most practical and basic method of verifying that a 
vehicle is in its certified configuration is through a vehicle 
emissions control information label, similar to that used for engines 
and light-duty vehicles. We proposed that this label list identifying 
features of the vehicle, including model year, vehicle model, certified 
engine family, vehicle manufacturer, test group, and GHG emissions 
category. In addition, this label would list emission-related 
components that an inspector could reference in the event of a field 
inspection. Possible examples may include LRR (for LRR tires), ARF 
(aerodynamic roof fairing), and ARM (aerodynamic rearview mirrors). 
With this information, inspectors could verify the presence and 
condition of attributes listed as part of the certified configuration.
    Several comments were received voicing concern that the large 
number of vehicle permutations within a given vehicle family (and 
perhaps vehicle subfamily) would lead to a large number of unique 
labels, at significant cost and labor burden to the manufacturer. In 
addition, including generic emission control system (EC) identifiers 
for vehicles would add a significant burden while providing little 
usable information for inspectors. A common example given in the 
comments was that simply identifying ``ARF'' for a roof fairing would 
not be sufficiently detailed for an inspector to know whether the 
correct roof fairing is present. As a result of these concerns, 
commenters suggested that vehicle labels only include a minimal amount 
of information such as a compliance statement, vehicle family name, and 
date of manufacture.
    The agencies generally agree with the concerns raised by the 
commenters and do not wish to add burdensome and arbitrary labeling 
requirements. Concurrently, we also remain committed to giving agency 
inspectors adequate tools to ensure a vehicle is in its certification 
at least at the time of sale. Therefore, we are finalizing a vehicle 
label requirement that includes:

--Compliance statement.
--Vehicle manufacturer.
--Vehicle family (and subfamily).
--Date of manufacture.
--Regulatory subcategory.
--Emission control system identifiers.

    To address the concerns from vehicle manufacturers identified 
above, particularly related to emission control (EC) identifiers, we 
believe a combination of selectable information on the label as well as 
a set of EPA-defined EC identifiers will provide a useful, but not 
overly burdensome labeling scheme. Since the intent of these 
identifiers is to provide inspectors with a means for simply verifying 
the presence of a component, we do not believe overly detailed 
identifiers are necessary, particularly for tires and aerodynamic 
components. For instance, current engine regulations require that 
three-way catalysts be identified on engine labels as ``TWC.'' However, 
unique details such as catalyst size, loading, location, and even the 
number of catalysts are not on the label. In similar fashion, we 
believe that identifying tires and aerodynamic components in a general 
sense will prove similarly effective in determining if a vehicle has 
been built as intended or if it has been modified prior to being 
offered for sale.
    EPA is requiring that components for which vehicle certification is 
dependent upon be identified on the label. This includes limited 
aerodynamic components (roof fairings, side skirts, & gap reducers), 
vehicle speed limiters, LRR tires, and idle reduction components. If 
vehicle certification also depends on the use of innovative or advanced 
technologies, this too must be included on the label. The following 
identifiers must be used for the emission control label:
Vehicle Speed Limiters
--VSL--Vehicle speed limiter.
--VSLS--``Soft-top'' vehicle speed limiter.
--VSLE--Expiring vehicle speed limiter.
--VSLD--Vehicle speed limiter with both ``soft-top'' and expiration.
Idle Reduction Technology
--IRT5--Engine shutoff after 5 minutes or less of idling.
--IRTE--Expiring engine shutoff.
Tires
--LRRD--Low rolling resistance tires--Drive (CRR of 8.2 kg/metric ton 
or less).
--LRRS--Low rolling resistance tires--Steer (CRR of 7.8 kg/metric ton 
or less).
--LRRA--Low rolling resistance tires--All (meeting appropriate criteria 
for steer & drive).
Aerodynamic Components
--ATS--Aerodynamic side skirt and/or fuel tank fairing.
--ARF--Aerodynamic roof fairing.
--ARFR--Adjustable height aerodynamic roof fairing.
--TGR--Gap reducing fairing (tractor to trailer gap).
Other Components
--ADV--Vehicle includes advanced technology components.
--ADVH--Vehicle includes hybrid powertrain.
--INV--Vehicle includes innovative technology components.

    On the vehicle label, several (if not all), available EC 
identifiers available in a given subfamily can be listed and the 
appropriate selections can be made at the time of assembly based on 
each unique vehicle configuration. This practice is common on engine 
ECI labels (normally for month/year of manufacture) and selections are 
made using a punch, stamp, check mark or other permanent method. This 
provides inspectors with the information they need while still 
affording flexibility to manufacturers with several unique vehicle 
configurations.
    At the time of certification, manufacturers will be required to 
submit an example of their vehicle emission control label such that EPA 
can verify that all critical elements mentioned above are present. In 
addition to the label, manufacturers will also need to describe where 
the unique vehicle identification number and date of production can be 
found on the vehicle (if the date is not present on the label).
    The agencies received several comments requesting the inclusion of 
consumer-focused labels for heavy-duty vehicles. These requests mainly 
involved labels similar to those found on passenger vehicles, allowing 
consumers to easily determine and compare fuel efficiency between 
vehicles. While we agree that such labels proven to be valuable to 
consumers in the light-duty market when shopping and comparing 
vehicles, the vast array of in-use drive cycles for heavy-duty vehicles 
and significant impact on GHG emissions reduce the intrinsic value of 
such fuel efficiency data to consumers. Additionally, many heavy-duty 
vehicles are unique and purpose-built which prevents direct comparison 
to other vehicles. The agencies may revisit this topic for future 
rulemaking activities, however there is no consumer label requirement 
in this final action.
(3) Other Certification Provisions
(a) Warranty
    Section 207 of the CAA requires manufacturers to warrant their 
products to be free from defects that would otherwise cause non-
compliance with emission standards. For purposes of this regulation, 
vehicle manufacturers must warrant all components which form the

[[Page 57278]]

basis of the certification to the GHG emission standards. The emission-
related warranty covers vehicle speed limiters, idle shutdown systems, 
fairings, hybrid system components, and other components to the extent 
such components are included in the certified emission controls. The 
emission-related warranty also covers tires and all components whose 
failure would increase a vehicle's evaporative emissions (for vehicles 
subject to evaporative emission standards, which could include 
components which received innovative or advanced technology credits). 
In addition, the manufacturer must ensure these components and systems 
remain functional for the warranty period defined in 40 CFR part 86 for 
the engine used in the vehicle, generally defined as half of the 
regulatory useful life. As with heavy-duty engines, manufacturers may 
offer a more generous warranty, however the emissions related warranty 
may not be shorter than any other warranty offered without charge for 
the vehicle. If aftermarket components are installed (unrelated to 
emissions performance) which offer a longer warranty, this will not 
impact emission related warranty obligations of the vehicle 
manufacturer. NHTSA, for this phase of the program, is not finalizing 
any warranty requirements relating to its fuel consumption rule.
    Several comments were received from vehicle manufacturers voicing 
concern that tire warranties should be the responsibility of the tire 
manufacturer, not the vehicle manufacturer. It has been, and remains, 
EPA policy to hold the certifying entities responsible for warranty 
obligations. In this case, tire manufacturers are not certificate 
holders and therefore we do not believe it is appropriate for them to 
independently warrant their products. The agencies see this as no 
different than requiring turbocharger or fuel injector manufacturers to 
provide warranties related to heavy-duty engines. However, we do 
believe that vehicle manufacturers can and should hold tire 
manufacturers responsible for warranty of their products as part of 
their sourcing and purchasing agreements. As proposed, tires are only 
required to be warranted for the first life of the tires (vehicle 
manufacturers are not expected to cover replacement tires). For heavy-
duty pickups and vans and combination tractors, the vehicle 
manufacturer is also required to warrant the A/C system against design 
or manufacturing defects causing refrigerant leakage in excess of the 
standard. The warranty period for the A/C system is identical to the 
vehicle warranty period as described above.
    At the time of certification, manufacturers must supply a copy of 
the warranty statement that will be supplied to the end customer. This 
document should outline what is covered under the GHG emissions related 
warranty as well as the length of coverage. Customers must also have 
clear access to the terms of the warranty, the repair network, and the 
process for obtaining warranty service.
(b) Maintenance
    Vehicle manufacturers are required to outline maintenance schedules 
that ensure their product will remain in compliance with emission 
standards throughout the useful life of the vehicle. For heavy-duty 
vehicles, such maintenance may include fluid/lubricant service, fairing 
adjustments, or service to the GHG emission control system. This 
schedule is required to be submitted as part of the application for 
certification. Maintenance that is deemed to be critical to ensuring 
compliance with emission standards is classified as ``critical 
emission-related maintenance.'' Generally, manufacturers are 
discouraged from specifying that critical emission-related maintenance 
is needed within the regulatory useful life of the engine. However, if 
such maintenance is unavoidable, manufacturers must have a reasonable 
basis for ensuring it is performed at the correct time. This may be 
demonstrated through several methods including survey data indicating 
that at least 80 percent of engines receive the required maintenance 
in-use or manufacturers may provide the maintenance at no charge to the 
user.
    Manufacturers will be required to submit the recommended emission-
related maintenance schedule (and other service related documentation) 
at the time of certification. This documentation should provide 
sufficient detail to allow the owner/operator of the vehicle to 
maintain the emission control system in a way that will ensure 
functionality as intended. This would include items such as periodic 
inspection of aerodynamic components and maintenance unique to advanced 
or innovative technologies. In addition, these instructions should 
provide the owner/operator with adequate information to replace 
consumable components (such as tires) with comparable replacements.
    Since low rolling resistance tires are key emission control 
components under this program, and will likely require replacement at 
multiple points within the life of a vehicle, it is logical to clarify 
how this fits into the emission-related maintenance requirements. While 
the agencies encourage the exclusive use of LRR tires throughout the 
life of heavy-duty vehicles, we recognize that it is inappropriate at 
this time to hold vehicle manufacturers responsible for ensuring that 
this occurs. Additionally, we believe that owner/operators have a 
legitimate financial motivation for ensuring their vehicles are as fuel 
efficient as possible, which includes purchasing LRR replacement tires. 
However owner/operators may not have a sound knowledge of which 
replacement tires to purchase to retain the as-certified fuel 
efficiency of their vehicle. To address this concern and in response to 
comments from vehicle manufacturers, we are requiring that vehicle 
manufacturers supply adequate information in the owner's manual to 
allow the owner/operator of the vehicle to purchase tires meeting or 
exceeding the rolling resistance performance of the original equipment 
tires. We expect that these instructions will be submitted to EPA as 
part of the application for certification.
(c) Certification Fees
    Similar to engine certification, the agency will assess 
certification fees for heavy-duty vehicles. The proceeds from these 
fees are used to fund the compliance and certification activities 
related to GHG regulation for this regulatory category. In addition to 
the certification process, other activities funded by certification 
fees include EPA-administered in-use testing, selective enforcement 
audits, and confirmatory testing. At this point, the exact costs 
associated with the heavy-duty vehicle GHG compliance are not well 
known. EPA will assess its compliance program cost associated with this 
program and assess the appropriate level of fees. We anticipate that 
fees will be applied based on vehicle families, following the light-
duty vehicle approach.
(d) Requirements for Conducting Aerodynamic Assessment Using the 
Modified Coastdown Reference Method and Alternative Aerodynamic Methods
    The requirements for conducting aerodynamic assessment using the 
modified coastdown reference method and alternative aerodynamic methods 
includes two key components: adherence to a minimum set of standardized 
criteria for each allowed method and submittal of aerodynamic values 
and supporting information on an annual basis for the purposes of 
certifying vehicles to a particular

[[Page 57279]]

aerodynamic bin as discussed in Section II.
    First, we are finalizing requirements for conducting the modified 
coastdown reference method and each of the alternative aerodynamic 
assessment methods. We will cite approved and published standards and 
practices, where feasible, but will define criteria where none exists 
or where more current research indicates otherwise. A description of 
the requirements for each method is discussed later in this section. 
The manufacturer will be required to provide performance data on its 
vehicles and attest to the accuracy of the information provided.
    Second, to ensure continued compliance, manufacturers will be 
required to provide a minimum set of information on an annual basis at 
certification time 1) to support continued use of an aerodynamic 
assessment method and 2) to assign an aerodynamic value based on the 
applicable aerodynamic bins. The information supplied to the agencies 
should be based on an approved aerodynamic assessment method and adhere 
to the requirements for conducting aerodynamic assessment mentioned 
above.
    The annual submission may be based on coastdown testing conducted 
consistent with the modified protocol detailed in this rulemaking or 
with an approved alternative method. The coastdown testing must be 
conducted using the Modified Protocol which uses SAE J1263 as a basis 
with some elements of SAE J2263 (e.g., post-processing and analysis 
techniques), in addition to the modifications developed in response to 
industry comments which raised concerns regarding test to test 
variability.
    In addition to 8 valid coastdown runs in each direction, 
manufacturers using in-house test methods should provide an adjustment 
factor for relating their drag coefficient based on their in-house 
method to the reference method, modified coastdown. The basis for the 
adjustment factor is:

Adjustment Factor = Cd coastdown / Cd in-house

    For the test article used for certification that differs from the 
test article used for reference method testing, determine Cd to use for 
aerodynamics bin determination as described below.

Cd certification BIN = Adjustment Factor x 
Cdin-house measured

    The specific requirements for the test article used in reference 
method testing using the coastdown procedures should meet the 
requirements listed in Table V-2 through Table V-5, below.

         Table V-2--Reference Method Test Vehicle Specifications
------------------------------------------------------------------------
                                             53' air ride dry vans
------------------------------------------------------------------------
Length...............................  53 feet (636 inches) +/- 1 inch.
Width................................  102 inches +/- 0.5 inches.
Height...............................  102 inches (162 inches or 13
                                        feet, 6 inches (+ 0.0 inch/ -1
                                        inch) from the ground).
Capacity.............................  3800 cubic feet.
Assumed trailer load/capacity........  45,000 lbs.
Suspension...........................  Any (see ``trailer ride height''
                                        below).
Corners..............................  Rounded with a radius of 5.5
                                        inches +/- 0.5 inches.
Bogie/Rear Axle Position.............  Tandem axle (std), 146 inches +/-
                                        3.0 inches from rear axle
                                        centerline to rear of trailer.
                                        Set to California position.
Skin.................................  Generally smooth with flush
                                        rivets.
Scuff band...........................  Generally smooth, flush with
                                        sides (protruding 8\
                                        inch).
Wheels...............................  22.5 inches. Duals. Std mudflaps.
Doors................................  Swing doors.
Undercarriage/Landing Gear...........  Std landing gear, no storage
                                        boxes, no tire storage, 105
                                        inches +/- 4.0 inches from
                                        centerline of king pin to
                                        centerline of landing gear.
Underride Guard......................  Equipped in accordance with 49
                                        CFR 393.86.
------------------------------------------------------------------------
Tires for the Standard Trailer and the Tractor:
    a. Size: 295/75R22.5 or 275/80R22.5.
    b. CRR metric ton (In addition, the CRR for trailer tires in
     GEM should be updated to 5.0 kg/metric ton.).
    c. Broken in per section 8.1 of SAE J1263.
    d. Pressure per section 8.5 of SAE J1263.
    e. No uneven wear.
    f. No re-treads.
    g. Should these tires or appropriate Smart Way tires not be
     available, the Administrator testing may include tires used by the
     manufacturer for certification.
------------------------------------------------------------------------
Test Conditions:
    1. Tractor-trailer gap: 45 inches +/- 2.0 inches.
    2. King pin setting: 36 inches +/- 0.5 inches from front of trailer
     to king pin center line.
    3. Trailer ride height: 115 inches +/- 1.0 inches from top of
     trailer to fifth wheel plate, measured at the front of the trailer,
     and set within trailer height boundary from ground as described
     above.
    4. Mudflaps: Positioned immediately following wheels of last axle.
------------------------------------------------------------------------

       Table V-3--Reference Method Coastdown Test Track Condition
                             Specifications
------------------------------------------------------------------------
               Parameter                              Range
------------------------------------------------------------------------
Coastdown speed range..................  70 mph to 15 mph.
Average wind speed at the test site       1 foot,
                                        overall.
                                       40 feet  1 foot,
                                        tank.
Width................................  96 inches  2.
Height...............................  140 inches (overall, from
                                        ground).
Capacity.............................  7,000 gallons.
Suspension...........................  Any (see ``trailer ride height''
                                        below).
Tank.................................  Generally cylindrical with
                                        rounded ends.
Bogie................................  Tandem axle (std). Set to
                                        furthest rear position.
Skin.................................  Generally smooth.
Structures...........................  (1) Centered, manhole (20 inch
                                        opening), (1) ladder generally
                                        centered on side, (1) walkway
                                        (extends lengthwise).
Wheels...............................  24.5 inches. Duals.
Tanker Operation.....................  Empty.
------------------------------------------------------------------------

    Table V-5--Standard Flatbed Reference Trailer for Special Testing
------------------------------------------------------------------------
                                                    Flatbed
------------------------------------------------------------------------
Length...............................  53 feet.
Width................................  102 inches.
Flatbed Deck Heights.................  Front: 60 inches  \1/
                                        2\ inch.
                                       Rear: 55 inches  \1/
                                        2\ inch.
Wheels/Tires.........................  22.5 inch diameter tire with
                                        steel or aluminum wheels.
Bogie................................  Tandem axles, may be in
                                        ``spread'' configuration up to
                                        10 feet  2 inches.
                                       Air suspension.
------------------------------------------------------------------------
Load Profile: 25 inches from the centerline to either side of the load;
Mounted 4.5 inches above the deck.
Load height 31.5 inches above the load support.

    Regardless of the method, all testing using high-roof sleepers 
should be performed with a tractor-trailer combination to mimic real 
world usage. Accordingly, it is important to match the type of tractor 
with the correct trailer. Although, as discussed elsewhere in this 
rulemaking, the correct tractor-trailer combination is not always 
present or tractor-only operation may occur, the majority of operation 
in the real world involves correctly matched tractor-trailer 
combinations and we will attempt to reflect that here. Therefore, when 
performing an aerodynamic assessment for a Class 7 and 8 tractor with a 
high roof, a standard box trailer must be used.
    The definitions of the standard trailer are further detailed in 
Sec.  1037.501(g). This ensures consistency and continuity in the 
aerodynamic assessments, and maintains the overlap with real world 
operation. As mid-roof and low-roof coastdown testing will be conducted 
without the trailer if the aerodynamic bin is not extrapolated from a 
high-roof version, then testing using other methods should also be 
conducted based on the tractor alone.
(e) Standardized Criteria for Aerodynamic Assessment Methods
(i) Coastdown Procedure Requirements
    For coastdown testing, the test runs should be conducted in a 
manner consistent with SAE J1263 with additional modifications as 
described in the 40 CFR part 1066, subpart C, and in Chapter 3 of the 
RIA using the mixed model analysis method. Since the coastdown 
procedure is the primary aerodynamic assessment method, the 
manufacturer would be required to conduct the coastdown procedure 
according to the requirements in this final action and supply the 
following information to the agency for approval:
     Facility information: name and location, description and/
or background/history, equipment and capability, track and facility 
elevation, track grade and track size/length;
     Test conditions for each test result including date and 
time, wind speed and direction, ambient temperature and humidity, 
vehicle speed, driving distance, manufacturer name, test vehicle/model 
type, model year, applicable model engine family, tire type and rolling 
resistance, test weight and driver name(s) and/or ID(s);
     Average Cd result as calculated in 40 CFR 
1037.520(b) from valid tests including, at a minimum, ten valid test 
results, with no maximum number, standard deviation, calculated error 
and error bands, and total number of tests, including number of voided 
or invalid tests.
(ii) Wind Tunnel Testing Requirements
    Wind tunnel testing would conform to the following procedures and 
modifications, where applicable, including:
     SAE J1252, ``SAE WIND TUNNEL TEST PROCEDURE FOR TRUCKS AND 
BUSES'' (July 1981) shall be followed with the following exceptions: 
section 5.2 is modified to specify a minimum Reynold's number 
(Remin) of 1.0x10\6\ and your model frontal area at zero yaw 
angle may exceed the recommended 5 percent of the active test section 
area, provided it does not exceed 25 percent;

[[Page 57281]]

section 6.0 is modified to add the requirement that, for reduced-scale 
wind tunnel testing, a one-eighth (\1/8\th) or larger scale model of a 
heavy-duty tractor and trailer must be used; for reduced-scale wind 
tunnel testing, section 6.1 is modified to add the requirement that the 
model be of sufficient design to simulate airflow through the radiator 
inlet grill and across an engine geometry representative of those 
commonly in your test vehicle.;
     J1594, ``VEHICLE AERODYNAMICS TERMINOLOGY'' (December 
1994); and
     J2071, ``AERODYNAMIC TESTING OF ROAD VEHICLES--OPEN THROAT 
WIND TUNNEL ADJUSTMENT'' (June 1994).
    In addition, the wind tunnel used for aerodynamic assessment would 
be a recognized facility by the Subsonic Aerodynamic Testing 
Association. If your wind tunnel is not capable of testing in 
accordance with these EPA modified SAE procedures, you may request EPA 
approval to use this wind tunnel and must demonstrate that your 
alternate test procedures produce data sufficiently accurate for 
compliance. This must be approved by EPA prior to method validation and 
correlation factor development. We are finalizing the provisions that 
manufacturers that perform wind tunnel testing do so based on the 
requirements detailed in this action. The wind tunnel tests should be 
conducted at a zero yaw angle and, if so equipped, utilizing the 
moving/rolling floor (i.e., the moving/rolling floor should be on 
during the test as opposed to static) for comparison to the coastdown 
procedure, which corrects to a zero yaw angle for the oncoming wind. 
However, manufacturers may be required to test at yaw angles other than 
zero (e.g., positive and negative six) if they voluntarily seek to 
improve their GHG emissions score for a given model using additional 
yaw sweep.
    The manufacturer is required to supply the following:
     Facility information: Name and location, description and 
background/history, layout, wind tunnel type, diagram of wind tunnel 
layout, structural and material construction;
     Wind tunnel design details: Corner turning vane type and 
material, air settling, mesh screen specification, air straightening 
method, tunnel volume, surface area, average duct area, and circuit 
length;
     Wind tunnel flow quality: Temperature control and 
uniformity, airflow quality, minimum airflow velocity, flow uniformity, 
angularity and stability, static pressure variation, turbulence 
intensity, airflow acceleration and deceleration times, test duration 
flow quality, and overall airflow quality achievement;
     Test/Working section information: Test section type (e.g., 
open, closed, adaptive wall) and shape (e.g., circular, square, oval), 
length, contraction ratio, maximum air velocity, maximum dynamic 
pressure, nozzle width and height, plenum dimensions and net volume, 
maximum allowed model scale, maximum model height above road, strut 
movement rate (if applicable), model support, primary boundary layer 
slot, boundary layer elimination method and photos and diagrams of the 
test section;
     Fan section description: Fan type, diameter, power, 
maximum rotational speed, maximum top speed, support type, mechanical 
drive, sectional total weight;
     Data acquisition and control (where applicable): 
Acquisition type, motor control, tunnel control, model balance, model 
pressure measurement, wheel drag balances, wing/body panel balances, 
and model exhaust simulation;
     Moving ground plane or Rolling Road (if applicable): 
Construction and material, yaw table and range, moving ground length 
and width, belt type, maximum belt speed, belt suction mechanism, 
platen instrumentation, temperature control, and steering; and
     Facility correction factors and purpose.
(iii) CFD Requirements
    Currently, there is no existing standard, protocol or methodology 
governing the use of CFD. Therefore, we are establishing a minimum set 
of criteria based on today's practices and coupling the use of CFD with 
empirical measurements from coastdown and, for gaining innovative 
technology credits, wind tunnel procedures. Since there are primarily 
two-types of CFD software code, Navier-Stokes based and Lattice-
Boltzman based, we are outlining two sets of criteria to address both 
types. Therefore, the agencies are requiring that manufacturers use 
commercially-available CFD software code with a turbulence model 
included or available. Further details and criteria for each type of 
commercially-available CFD software code follows immediately and 
general criteria for all CFD analysis are subsequently described.
    For Navier-Stokes based CFD code, manufacturers must perform an 
unstructured, time-accurate analysis using a mesh grid size with total 
volume element count of at least fifty million cells of hexahedral and/
or polyhedral mesh cell shape, surface elements representing the 
geometry consisting of no less than six million elements and a near 
wall cell size corresponding to a y+ value of less than three hundred 
with the smallest cell sizes applied to local regions of the tractor 
and trailer in areas of high flow gradients and smaller geometry 
features. Navier-Stokes-based analysis should be performed with a 
turbulence model (e.g., k-epsilon (k-[egr]), shear stress transport k-
omega (SST k-[ohgr]) or other commercially-accepted method) and mesh 
deformation (if applicable) enabled with boundary layer resolution of 
+/- 95 percent. Finally, Navier-Stokes based CFD analysis for the 
purposes of determining the Cd should be performed once result 
convergence is achieved. Manufacturers should demonstrate convergence 
by supplying multiple, successive convergence values.
    For Lattice-Boltzman based CFD code, manufacturers must perform an 
unstructured, time-accurate analysis using a mesh grid size with total 
number of volume elements of at least fifty million with a near wall 
cell size of no greater than six millimeters on local regions of the 
tractor and trailer in areas of high flow gradients and smaller 
geometry features, with cell sizes in other areas of the mesh grid 
starting at twelve millimeters and increasing in size from this value 
as the distance from the tractor-trailer model increases.
    In general for CFD, all analysis should be conducted using the 
following conditions: A tractor-trailer combination using the 
manufacturer's tractor and the trailer according to the trailer 
specifications in this regulation, an environment with a blockage ratio 
of less than or equal to 0.2 percent to simulate open road conditions, 
a zero degree yaw angle between the oncoming wind and the tractor-
trailer combination, ambient conditions consistent with the modified 
coastdown test procedures outlined in this regulation, open grill with 
representative back pressures based on data from the tractor model, 
turbulence model and mesh deformation enabled (if applicable), and 
tires and ground plane in motion consistent with and simulating a 
vehicle moving in the forward direction of travel. For any CFD 
analysis, the smallest cell size should be applied to local regions on 
the tractor and trailer in areas of high flow gradients and smaller 
geometry features (e.g., the a-pillar, mirror, visor, grille and 
accessories, trailer leading and trailing edges, rear bogey, tires, 
tractor-trailer gap).
    Finally, with administrator approval, a manufacturer may request 
and

[[Page 57282]]

perform CFD analysis using parameters and criteria other than stated 
above if the manufacturer can demonstrate that the conditions above are 
not feasible (e.g., insufficient computing power to conduct such 
analysis, inordinate length of time to conduct analysis, equivalent 
flow characteristics with more feasible criteria/parameters) or 
improved criteria may yield better results (e.g., different mesh cell 
shape and size). A manufacturer must provide data and information that 
demonstrates that their parameters/criteria will provide a sufficient 
level of detail to yield an accurate analysis including comparison of 
key characteristics between the manufacturer's criteria/parameters and 
those stated above (e.g., pressure profiles, drag build-up, and/or 
turbulent/laminar flow at key points on the front of the tractor and/or 
over the length of the tractor-trailer combination).
Alternative Aerodynamic Method Comparison to the Coastdown Test 
Procedure Reference Method
    If a manufacturer uses any alternative aerodynamic method, or any 
method other than the coastdown reference method, the manufacturer 
would have to provide a comparison to the coastdown test procedure 
reference method. The manufacturer would be required to perform the 
alternative aerodynamic method and the coastdown test procedure 
reference method on the same model and compare the Cd results. The 
alternative aerodynamic method, or any other method using good 
engineering judgment, and the coastdown test procedure reference method 
must be conducted under similar test conditions and adhere to the 
criteria discussed above for each aerodynamic assessment method.
    This demonstration would be performed in the initial year of rule 
implementation and would require agency review and approval prior to 
use of the alternative aerodynamic method in future years and for other 
models.
    The comparison would occur on one model of the manufacturer's 
highest sales volume, Class 8, high roof, sleeper cab family with a 
full aerodynamics package, either equipped at the factory or sold 
through a dealer specifically for that model as an OEM part. If the 
manufacturer does not have such a model, the manufacturer may select a 
comparable model in that family or a model from another highest sales 
volume family in the manufacturer's fleet.
    For the comparison, the manufacturer would be required to provide 
information on the test conditions for each test result including but 
not limited to: test date and time, wind speed (if applicable), 
temperature, humidity, manufacturer and model, model year, applicable 
model engine family, tire type and rolling resistance for actual model, 
model test weight, equivalent vehicle test weight, actual and simulated 
or equivalent vehicle speed, Reynolds number (if applicable), yaw angle 
(if applicable), blockage ratio, either calculated or measured (if 
applicable), model mounting (if applicable), model geometry, body axis 
force and moments (if applicable), total test duration, test vehicle 
and type and operator name(s) and/or ID(s). In addition, the 
manufacturer must provide the Cd results from valid tests.
    Once the comparison is performed in the initial year, the 
manufacturer is required to perform this comparison every three years 
on the highest sales volume, Class 8, high roof, sleeper cab family 
equipped with a full aerodynamics package unless any or all of the 
following occurs: the Class 8, high roof, sleeper cab family/model used 
for the original comparison is no longer commercially available, and/or 
significantly redesigned, with the meaning of ``significantly'' based 
on good engineering judgment, a fundamental change is made to the 
current alternative aerodynamic method (e.g., change from facility A to 
facility B as a source), and/or the alternative aerodynamic method is 
changed to something other than the coastdown test procedure reference 
method (e.g., switch to wind tunnel testing from coastdown, change wind 
tunnel testing facilities or CFD software code). However, the agency 
reserves the right and has the authority under the Clean Air Act (CAA) 
to request and have the manufacturer perform a comparison in any year 
and on any model that the manufacturer has certified.
    Finally, the data generated for the purpose of this comparison can 
be used in annual certification for that model, also called the base 
model, and for determining Cd for other models and/or sub-families in 
the base model family, or other families in the manufacturer's fleet.
Annual Certification Data Submittal for Aerodynamic Assessment
    For each model in the manufacturer's fleet, the manufacturer is 
required to supply aerodynamic information on an annual basis to the 
agencies in their certification application. Once the manufacturer has 
performed the coastdown test procedure or the comparison for an 
alternative aerodynamic method, the aerodynamic assessment method can 
be used to generate Cd values for all models the 
manufacturer plans to certify and introduce into commerce. For each 
model, the manufacturer would determine a predicted aerodynamic drag 
(Cd times the frontal area, A). This reduces burden on the 
manufacturer to perform aerodynamic assessment but provides data for 
all the models in a manufacturer's fleet. If a manufacturer has 
previously performed aerodynamic assessment on the other models, the 
manufacturer may submit an experimental Cd in lieu of a 
predicted Cd.
    The aerodynamic assessment data will be used in one of two ways: 
the manufacturer will use the Cd (times A) values to 
determine the correct GEM input according to agency-defined tables, or 
the agencies will use the manufacturer's input data into the model and 
assign a GHG value/score.
    Since the agencies may input the data into the model, manufacturers 
are required to provide the information from the coastdown test 
procedure, alternative aerodynamic method or the method comparison 
described above for annual certification. In addition, the manufacturer 
would supply manufacturer fleet information to the agency for annual 
certification purposes along with the acceptance demonstration 
parameters: manufacturer name, model year, model line (if different 
than manufacturer name), model name, engine family, engine 
displacement, transmission name and type, number of axles, axle ratio, 
vehicle dimensions, including frontal area, predicted or measured 
coefficient of drag, assumptions used in developing the predicted or 
measured Cd, justification for carry-across of aerodynamic 
assessment data, photos of the model line-up, if available, and model 
applications and usage options.
    Finally, the agencies reserve the right to request that a 
manufacturer generate or provide additional data, prior to 
certification, to support and receive annual certification approval.
(f) Aerodynamic Validation and Compliance Audit
    The agencies reserve the right to perform aerodynamic validation 
and compliance audit of the manufacturer's aerodynamic results. The 
agencies may conduct a vehicle confirmatory evaluation using a vehicle 
recruited from the in-use fleet and performing the reference method, 
coastdown test procedures, either at the manufacturer's facility or an 
independent facility using the agencies equipment and tools. If there 
is a discrepancy between the

[[Page 57283]]

manufacturer's data submitted for certification and the agencies' 
validation results, the agency may perform a full audit of the 
manufacturer's source data and aerodynamic assessment methods and tools 
used by the manufacturer to produce the data. The manufacturer would be 
required to make all equipment and tools available to the agencies to 
conduct the full audit.
    Based on this audit, the agencies may require the manufacturer to 
make changes to their aerodynamic assessment methods ranging from minor 
adjustments to method criteria to switching allowed aerodynamic 
assessment methods. For the purposes of aerodynamic validation and 
compliance audit, manufacturers will be allowed an additional 
compliance margin of one bin from the certified bin for the model 
evaluated (e.g., if a manufacturer certifies a model to Bin IV, the 
results of the aerodynamic valid/compliance audit must fall within the 
next highest bin, in this case Bin III). In addition, the agencies may 
select any model from the manufacturer's fleet/vehicle family to 
perform the aerodynamic validation and compliance.
(g) Aerodynamic Bin Category Adjustment Using Yaw Sweep Information
    As discussed in Section II.B.2, the agencies are finalizing 
aerodynamic drag values which represent zero degree yaw (i.e., 
representing wind from directly in front of the vehicle, not from the 
side). We recognize that wind conditions, most notably wind direction, 
have a greater impact on real world CO2 emissions and fuel 
consumption of heavy-duty trucks than of light-duty vehicles. To 
provide additional incentive for manufacturers using aerodynamic 
techniques (i.e., techniques that use assessment at yaw angles more or 
less than zero degrees to capture the influence of side winds and 
calculate wind average drag coefficient), the agencies are defining an 
approach to allow manufacturers to account for improved aerodynamic 
performance in crosswind conditions similar to those experienced by 
vehicles in use. If a manufacturer can benefit from having a model that 
performs in regimes or conditions other than the scope of the test 
parameters in this rulemaking, this creates an incentive for the entire 
industry. As a result, we are allowing manufacturers to use the 
coefficient of drag values at positive six, negative six, and zero 
degrees yaw to improve their GHG score.
    The Yaw Sweep Adjustment would be determined using the following 
steps and equations:
     Step 1: Determine your aero method adjustment factor as 
described above in paragraph (d) of this section and using the 
equation;
[GRAPHIC] [TIFF OMITTED] TR15SE11.005

     Step 2: Apply the aerodynamic method adjustment factor to 
the positive six, negative six and zero degrees yaw Cd values for that 
model using the equation;

Cd Adjusted = Adjustment Factor x 
Cd(+6 degrees/-6 degrees/0 degrees, model) Step 3: Calculate your Adjusted zero yaw Cd*A

Adjusted Zero Yaw Cd*A(model) = adjusted +/- Six Yaw 
Cd(average,model) *A(model) x Zero Yaw Cd*A(industry 
average) +/-Six Yaw Cd(average)*A(industry average) Step 4: Use the adjusted zero yaw Cd*A for the model to 
determine appropriate bin and the associated Cd input for the GEM to 
determine your Yaw Sweep Adjusted GHG score.
    Essentially, this equation becomes y = x * C where y is the 
adjusted zero yaw Cd, x is the corrected average of the +/- six degree 
yaw Cds for the manufacturer's model, and C is a constant value based 
on the ratio of the zero yaw Cd and WACd ratio for the industry. The 
current default value for this industry baseline ratio for this is 
rulemaking is 0.8065 based on the Cd values of current Class 8, high-
roof, aero sleeper cab models in the fleet. The agencies may 
periodically review this industry baseline ratio and adjust it, if 
necessary, with notification to the industry.
    The yaw sweep adjustment described above only applies to Class 7, 
high-roof day cab and Class 8 high-roof day or sleeper cab tractors and 
a manufacturer seeking yaw sweep adjustment must use an approved, 
alternative aerodynamic method to generate the yaw sweep data. 
Manufacturers may use a more yaw sweep angles (e.g., zero, +/- 1, 3, 6, 
9) for their yaw sweep adjustment and, in this case, must calculate the 
wind-average Cd (WACd) according to SAE J1252 and use this value in 
lieu of the average of the +/- six degree yaw Cds in the equations 
above.
    As stated elsewhere in this regulation, the Agencies reserve the 
right to review a manufacturer's proposed adjustment and discuss the 
proposed adjustment with the manufacturer. The Agencies will notify the 
manufacturer of the need for a review and the manufacturer must provide 
all information requested by the Agencies to support the review and 
subsequent discussion(s). The agencies also reserve the right to deny 
aerodynamic bin category adjustment independent or as a result of the 
review/discussions with the manufacturer. In such case, the Agencies 
will notify the manufacturer of denial prior to certification to ensure 
the proper inputs to the GEM are used.
(4) Compliance Reports
(a) Early Model Year Data
    The regulatory text of the NPRM included specifications for 
manufacturers to submit pre-certification compliance reports for each 
of a manufacturer's fleet of heavy-duty tractors. Navistar and Volvo 
commented that the requirements specified in the NHTSA pre-
certification reports are overbroad and should be eliminated. The pre-
certification reports included requirements for manufactures to submit 
a wide variety of information on these vehicles. The variety of 
information was believed to be necessary given that these vehicles had 
no previous compliance information for meeting fuel efficiency and 
emission standards and the agencies wanted to ensure that enough 
information was obtain to ensure sufficient compliance with the 
program. The agencies have since reviewed the level of detail required 
in the precertification reports and are in agreement with commenters 
that the required information may be overly broad for compliance 
purposes and given that this is the first time these manufacturers have 
been regulated, the level of information required may not be available 
until subsequent model years. Therefore, as discussed previously for 
pickup trucks and vans, the agencies have removed the requirement for

[[Page 57284]]

manufactures to submit pre-certification compliances reports for these 
classes of vehicles.
    As an alternative to receiving early compliance model year 
information in the precertification reports, the agencies have decided 
to use manufacturer's application for certificates of conformity to 
obtain early model estimates. Currently, the applications for 
certificates are not required to include the fuel consumption 
information required by NHTSA. Therefore, the agencies are adopting 
provisions in the final rules for manufacturers to provide emission and 
equivalent fuel consumption estimates in the manufacturer's 
applications for certification. The agencies will treat information 
submitted in the applications as a manufacturer's demonstration of 
providing early compliance information, similar to the pre-model year 
report submitted for heavy-duty pickup trucks and vans. The final rule 
establishes a harmonized approach by which manufacturers will submit 
applications through an EPA-administered database, such as the Verify 
system, as the single point of entry for all information required for 
this national program and both agencies will have access to the 
information. If by model year 2012, the agencies are not prepared to 
receive information through the EPA Verify database system, 
manufacturers are expected to submit written applications to the 
agencies. This approach should streamline this process and reduce 
industry burden and provide sufficient information for the agencies to 
carry out their early compliance activities.
(b) Final Reports
    The NPRM proposed for manufacturers participating in the ABT 
program to provide EOY and final reports. The EOY reports for the ABT 
program were required to be submitted by manufacturers no later than 90 
days after the calendar year and final report no later than 270 days 
after the calendar year.\318\ Manufacturers not participating in the 
ABT program were required to provide an EOY report within 45 days after 
the calendar year but no final reports were required. The final ABT 
report due was established coinciding with EPA's existing criteria 
pollutant report for heavy-duty engines. The EOY report was required in 
order to receive preliminary final estimates and identifies 
manufacturers that might have a credit deficit for the given model 
year. Manufacturers with a credit surplus at the end of each model 
could receive a waiver from providing EOY reports. As proposed, the 
remaining manufacturers were required to submit reports to EPA and send 
copies of those reports to NHTSA with equivalent fuel consumption 
values.
---------------------------------------------------------------------------

    \318\ Corresponding to the compliance model year.
---------------------------------------------------------------------------

    In response to the NPRM, commenters recommended collecting 
additional data. One commenter requested collecting information to 
develop and refine test cycles that more accurately reflect actual 
driving cycles for medium- and heavy-duty trucks. Several other 
commenters (ACEE, Eaton, CALSTART, NRDC and UCS) recommended collecting 
advanced data on in-service vehicles and that the collected data be 
analyzed and characterized for each vocational application, especially 
for hybrid vehicles, in a cooperative government and industry effort. 
Commenters (ACEE, DTNA, NRGDC, UCS and Volvo) also requested that the 
agency's data collection ensure to include information on actual 
vehicle configurations sold in the fleet.
    Many commenters argued against the burden placed upon the industry 
in meeting the agencies' proposed required reporting provisions. One 
commenter argued against providing actual production information due to 
the variability that exists in building heavy-duty vehicles and in the 
influence of changing fleet interest each year indicating that only 
estimated information should have to be provided. Commenters (Volvo and 
Navistar) generally objected stating that the agency requirements in 
its reports are both unnecessary and overly burdensome. Comments in 
response to the NPRM requested that for manufacturers not using ABT 
provisions, the EOY report due 45 days after the end of the calendar 
year should be combined with the ABT report due 90 days after the same 
model year. Commenters also requested that the exempted off-road 
vehicle report be consolidated with the EOY report. Other concerns 
raised by commenters were for the agencies to remove any differences in 
reporting provisions and implement a single uniform reporting template 
that manufacturers can submit to both agencies.
    One commenter (Volvo) requested that the agencies simplify the 
reporting requirements for vehicle configurations in both the EOY and 
final reports, commenting that the proposal as outlined was extremely 
burdensome to vehicle manufacturers. The NPRM regulation stated that 
the manufacturer must identify each distinguishable vehicle 
configuration in the vehicle family or sub-family and identification of 
FELs for each subfamily. The regulation calls for reporting of results 
and modeling inputs for each subfamily. The commenter believed that the 
burden of meeting these requirements for the vast number of families/
subfamilies is substantial and unjustified. For this commenter, there 
is a potential for almost 45 million sub-families in the vocational and 
tractor categories. This approach should reduce the number of vehicle 
families to an amount that is suitable for reporting. The BlueGreen 
Alliance and ACEEE also requested the agencies to implement a program 
as part of the final rule to collect data, actual vehicle 
configurations sold and their performance as estimated by simulation 
modeling, which will provide information required to develop a full-
vehicle program in the future.
    For the final rules, the agencies are requiring EOY and final 
reports, as proposed. However, the agencies will consolidate the 
reporting as requested by comments and is requiring equivalent fuel 
consumption information for all reports submitted to EPA. The final 
rules establish a harmonized approach by which manufacturers will 
submit reports through an EPA-administered database, such as the Verify 
system, as the single point of entry for all information required for 
this national program and both agencies will have access to the 
information. If by model year 2012, the agencies are not prepared to 
receive information through the EPA Verify database system, 
manufacturers are expected to submit written reports to the agencies. 
The agencies are also combining the EOY reports for manufacturers not 
using ABT provisions with other EOY reports and are requiring a 
submission date 90 days after the calendar year. The agencies view the 
adopted requirements in the final rules for EOY and final reports will 
provide sufficient data requests to satisfy these requests. The 
agencies also agree with Volvo's concerns and have adopted a new 
classification system for selecting vehicle families as described 
elsewhere in this section. A summary of the required information in the 
final rules for EOY and final reports is as follows:
     Vehicle family designation and averaging set.
     Vehicle emissions and fuel consumption standards including 
any alternative standards used.
     Vehicle family FELs.
     Final production volumes.
     Certified test cycles.
     Useful life values for vehicle families.

[[Page 57285]]

     A credit plan identifying the manufacturers actual credit 
balances, credit flexibilities, credit trades and a credit deficit plan 
if needed demonstrating how it plans to resolve any credit deficits 
that might occur for a model year within a period of up to three model 
years after that deficit has occurred.
     A plan describing the vehicles that were exempted such as 
for off-road or small business purposes.
     A plan describing any alternative fueled vehicles that 
were produced for the model year identifying the approaches used to 
determinate compliance and the production volumes.
(c) Additional Required Information
    Throughout the model year, manufacturers may be required to report 
various submissions to the agencies to comply with various aspects of 
the rules. These requests have differing criteria for submission and 
approval. Table V-6 below provides a summary of the types of 
submission, required submission dates and the EPA and NHTSA regulations 
that apply. The agencies will review and grant requests considering the 
timeliness of the submissions and the completeness of the requests.

                            Table V-6--Summary of Required Information for Compliance
----------------------------------------------------------------------------------------------------------------
                                                                                                       NHTSA
            Submission                    Applies to        Required submissions  EPA regulation    regulation
                                                                    date             reference       reference
----------------------------------------------------------------------------------------------------------------
Small business exemptions.........  Vehicle manufacturers  Before introducing               Sec.    Sec.   535.8
                                     meeting the Small      any excluded vehicle        1037.150
                                     Business               into U.S. commerce.
                                     Administration (SBA)
                                     size criteria of a
                                     small business as
                                     described in 13 CFR
                                     121.201.
Incentives for early introduction.  The provisions apply   EPA must be notified             Sec.    Sec.   535.8
                                     with respect to        before the                  1037.150
                                     tractors and           manufacturer submits
                                     vocational vehicles    its applications for
                                     produced in model      certificates of
                                     years before 2014.     conformity.
Voluntary compliance for NHTSA      Vehicle manufacturers  NHSAT must be                      NA    Sec.   535.8
 standards.                          seeking early          notified before the
                                     compliance in model    manufacturer submits
                                     years 2014 to 2016.    its applications for
                                                            certificates of
                                                            conformity.
Approval of alternate methods to    Tractors meeting Sec.  EPA must be notified             Sec.    Sec.   535.8
 determine drag coefficients.          1037.106.            before the                  1037.150
                                                            manufacturer submits
                                                            its applications for
                                                            certificates of
                                                            conformity.
Off-road exemption................  Manufacturers wanting  EPA must be notified             Sec.    Sec.   535.8
                                     to exclude tractors    before the                  1037.150
                                     from vehicle           manufacturer submits
                                     standards.             its applications for
                                                            certificates of
                                                            conformity.
Vocational Tractor................  Manufacturers wanting  EPA must be notified             Sec.    Sec.   535.8
                                     to reclassify          before the                  1037.150
                                     tractor as             manufacturer submits
                                     vocational tractors    it applications for
                                     making them            certificates of
                                     applicable to          conformity.
                                     vocational vehicle
                                     standards.
Exemption from EOY reports........  Manufactures with      90-days after the                Sec.    Sec.   535.8
                                     surplus credits at     calendar year ends.         1037.730
                                     the end of the model
                                     year.
----------------------------------------------------------------------------------------------------------------

E. Class 2b-8 Vocational Vehicles

(1) Final Compliance Approach
    Like Class 7 and 8 combination tractors, heavy-duty vocational 
vehicles will be required to have both engine and chassis certificates 
of conformity. As discussed in the engine certification section, 
engines that will be used in vocational vehicles would need to be 
certified using the heavy-duty FTP cycle for GHG pollutants and show 
compliance through the useful life of the engine. This certification is 
in addition to the current requirements for obtaining a certificate of 
conformity for criteria pollutant emissions.
    For this final action, the majority of the GHG reduction for 
vocational vehicles is expected to come from the use of LRR tires as 
well as increased utilization of hybrid powertrain systems. Other 
technologies such as aerodynamic improvements and vehicle speed 
limiting systems are not as relevant for this class of vehicles, since 
the typical duty cycle is much more urban, consisting of lower speeds 
and frequent stopping. Idle reduction strategies are expected to be 
encompassed by hybrid technology, which we anticipate will ultimately 
handle PTO operation as well. Therefore, for this final action, 
certification of heavy-duty vocational vehicles with conventional 
powertrains will focus on quantifying GHG benefits due to the use of 
LRR tires through the GEM.
(a) Certification Process
    Vehicles will be divided into vehicle families for purposes of 
certification. As with Class 7 and 8 combination tractors, these are 
groups of vehicles within a given regulatory subcategory that are 
expected to share common emission characteristics. Vocational vehicle 
regulatory subcategories share the same structure as those used for 
heavy-duty engine criteria pollutant certification and are based on 
GVWR. This includes light-heavy (LHD) with a GVWR at or below 19,500 
pounds, medium-heavy (MHD) with a GVWR above 19,500 pounds and at or 
below 33,000 pounds, and heavy-heavy (HHD) with a GVWR above 33,000 
pounds. We anticipate manufacturers will have one vehicle family per 
regulatory subcategory, however hybrid vehicles will need to be 
separated into additional unique vehicle families. Manufacturers may 
also subdivide families into sub-families if GHG emissions performance 
is expected to change significantly within the vehicle family. As with 
Class 7 and 8 combination tractors, we anticipate using the 
standardized 12-digit naming convention to identify vocational vehicle 
families. As with engines and Class 7 and 8 combination tractors, each 
certifying vehicle manufacturer would have a unique three digit code 
assigned to them. Currently, there is no 5th digit (industry sector) 
code for this class of vehicles and EPA will issue an update to the 
current guidance explaining which character(s) should be used for 
vocational vehicles. The agencies originally proposed that engine 
displacement be included in the vehicle family name, however the wide 
range of engines available across most regulatory

[[Page 57286]]

subcategories makes this requirement irrelevant and unnecessary at the 
time of this rulemaking. Therefore, we are reserving the remaining 
characters for California ARB and/or manufacturer use, such that the 
result is a unique vehicle family name.
    Each vehicle family must demonstrate compliance with emission 
standards using the GEM. GEM inputs for conventional (i.e. non-hybrid) 
vocational vehicles primarily involves entering tire rolling resistance 
information. Additional provisions are available for certification of 
hybrid vehicles or vehicles using other advanced or innovative 
technologies, as detailed in Section IV. If the vehicle family consists 
of multiple configurations, only results from the worst-case 
configuration are necessary for certification in addition to an 
engineering evaluation demonstrating that the modeled configuration 
indeed reflects the worst-case configuration. If the vehicle family is 
divided into subfamilies, unique GEM results are required for at least 
one configuration per subfamily.
    The agencies have received comments from engine manufacturers, 
truck manufacturers, and hybrid system manufacturers raising concerns 
regarding the duty cycles and the weighting factors proposed for 
evaluating transient applications. The agencies proposed three methods 
for evaluating hybrid system performance in an effort to generate 
credits. The proposed duty cycles considered for the proposal will 
continue to be used with this final action. The Agencies proposed a 
transient duty cycle, a 55 mile-per-hour steady state cruise and a 65 
mile per hour steady state cruise. The transient duty cycle, is 
essentially the same transient cycle proposed in the NPRM with the 
exception that it minimizes inappropriate shift events. Additionally, 
the steady state cycles proposed by the Agencies remain essentially 
unchanged. In response to concerns raised by engine manufacturers and 
hybrid system manufacturers regarding the operation of vehicles most 
likely to be hybridized in the near term, we are modifying the 
weighting factors for each cycle to address the distribution of the 
emissions impact associated with each duty cycle. The weighting factors 
will be changed such that a greater emphasis on the type of transient 
activity seen as more characteristic of hybrid applications will be 
evident. The new weighting factors between duty cycles for hybrid 
certification will be 75 percent for the transient, 9 percent for the 
55 mph cruise cycle, and 16 percent for the 65 mph cruise cycle. The 
basis for this change may be seen in the memorandum to Docket EPA-HQ-
OAR-2010-0162, which describes the data set used to describe real world 
vehicle performance. In addition to this modification, the Power-Take-
Off (PTO) operation will be characterized for vehicles utilizing a PTO 
system for which there is a benefit for use of the hybrid technology. 
The testing provisions for the comparison in the A to B testing for 
complete vehicle or post-transmission powerpack testing may be seen in 
40 CFR 1037.525. The testing provisions for work-specific pre-
transmission evaluation using an engine based approach may be seen in 
40 CFR 1036.525.
(b) Demonstrating Compliance With the Final Standards
(i) CO2 and Fuel Consumption Standards
Model
    As stated above, the technology basis for the final standards for 
vocational vehicles is use of LRR tires. Similar to Class 7 and 8 
combination tractors, compliance with the standards will be 
demonstrated using the GEM predictive model. However, the input 
parameters entered by the vehicle manufacturer would be limited to the 
properties of the tires. The GEM will use the tire data, along with 
inputs reflecting a baseline truck and engine, to generate a complete 
vehicle model. The test weight used in the model will be based on the 
vehicle class, as identified above. Light-heavy-duty vehicles will have 
a test weight of 16,000 pounds; 25,150 pounds for medium heavy-duty 
vehicles; and heavy heavy-duty vocational vehicles will use a test 
weight of 67,000 pounds. The model would then be exercised over the 
HHDDT transient cycle as well as 55 and 65 mph steady-state cruise 
conditions. The results of each of the three tests would be weighted at 
16%, 9%, and 75% for 65 mph, 55 mph, and transient tests, respectively. 
Innovative technology credits may be used to demonstrate compliance, 
however because the technology would not be an input into GEM, 
alternative procedures would be needed to determine the value of the 
credit as described in Preamble Section IV.
    It may seem more expedient and just as accurate to require 
manufacturers use tires meeting certain industry standards for 
qualifying tires as having LRR. In addition, CO2 and fuel 
consumption benefits could be quantified for different ranges of 
coefficients of rolling resistance to provide a means for comparison to 
the standard. However, we believe that as technology advances, other 
aspects of vocational vehicles may warrant inclusion in future 
rulemakings. For this reason, we remain committed to having the 
certification framework in place to accommodate such additions. While 
the modeling approach may seem to be overly complicated for this phase 
of the rules, it also serves to create a certification pathway for 
future rulemakings and therefore we believe this is the best approach. 
Moreover, a design standard would discourage use of alternative 
technologies to meet the standard, and otherwise impede desirable 
flexibility.
In-use Standards
    The category of wear items primarily relates to tires. It is 
expected that vehicle manufacturers will equip their trucks with LRR 
tires, since the final vehicle standard is predicated on LRR tire 
performance. The tire replacement intervals for this class of vehicle 
is normally in the range of 50,000 to 100,000 miles, which means the 
owner/operator will be replacing the tires at several points within the 
useful life of the vehicle. We believe that as LRR tires become more 
common on new equipment, the aftermarket prices of these tires will 
also decrease. Along with decreasing tire prices, the fuel savings 
realized through use of LRR tires will ideally provide enough incentive 
for owner/operators to continue purchasing these tires. The inventory 
modeling in this rulemaking package reflects the continued use of LRR 
tires through the life of the vehicle.
(ii) Evaporative Emission Standards
    Evaporative and refueling emissions from heavy-duty highway engines 
and vehicles are currently regulated under 40 CFR part 86. Even though 
these emission standards apply to the same engines and vehicles that 
must meet exhaust emission standards, we require a separate certificate 
for complying with evaporative and refueling emission standards. An 
important related point to note is that the evaporative and refueling 
emission standards always apply to the vehicle, while the exhaust 
emission standards may apply to either the engine or the vehicle. For 
vehicles other than pickups and vans, the standards in this program to 
address greenhouse gas emissions apply separately to engines and to 
vehicles. Since we will be applying both greenhouse gas standards and 
evaporative/refueling emission standards to vehicle manufacturers, we 
believe it will be advantageous to have the regulations related to 
their certification requirements written

[[Page 57287]]

together as much as possible. EPA regards these final changes as 
discrete, minimal, and for the most part clarifications to the existing 
standards. We have not finalized any changes to the evaporative or 
refueling emission standards, but we have come across several 
provisions that warrant clarification or correction:
 When adopting the most recent evaporative emission change we 
did not carry through the changes to the regulatory text applying 
evaporative emission standards for methanol-fueled compression-ignition 
engine. The final regulations correct this by applying the new 
standards to all fuels that are subject to standards.
 We are finalizing provisions to address which standards apply 
when an auxiliary (nonroad) engine is installed in a motor vehicle, 
which is currently not directly addressed in the highway regulation. 
The final approach requires testing complete vehicles with any 
auxiliary engines (and the corresponding fuel-system components). 
Incomplete vehicles must be tested without the auxiliary engines, but 
any such engines and the corresponding fuel system components will need 
to meet the standards that apply under our nonroad program as specified 
in 40 CFR part 1060.
 We have removed the option for secondary vehicle manufacturers 
to use a larger fuel tank capacity than is specified by the certifying 
manufacturer without re-certifying the vehicle. Secondary vehicle 
manufacturers needing a greater fuel tank capacity will need to either 
work with the certifying manufacturer to include the larger tank, or go 
through the effort to re-certify the vehicle itself. Our understanding 
is that this provision has not been used and would be better handled as 
part of certification rather than managing a separate process. We are 
also finalizing corresponding changes to the emission control 
information label.
 Rewriting the regulations in a new part in conjunction with 
the greenhouse gas standards allows for some occasions of improved 
organization and clarity, as well as updating various provisions. For 
example, we have finalized a leaner description of evaporative emission 
families that does not reference sealing methods for carburetors or air 
cleaners. We have also clarified how evaporative emission standards 
affect engine manufacturers and are finalizing more descriptive 
provisions related to certifying vehicles above 26,000 pounds GVWR 
using engineering analysis.
 Since we adopted evaporative emission standards for gaseous-
fuel vehicles, we have developed new approaches for design-based 
certification (see, for example, 40 CFR 1060.240). We request comment 
on changing the requirements related to certifying gaseous-fuel 
vehicles to design-based certification. This would allow for a simpler 
assessment for certifying these vehicles without changing the standards 
that apply.
(2) Final Labeling Provisions
    It is crucial that a means exist for allowing field inspectors to 
identify whether a vehicle is certified, and if so, whether it is in 
the certified configuration. As with engines and tractors, we believe 
an emission control information label is a logical first step in 
facilitating this identification. For vocational vehicles, the engine 
will have a label that is permanently affixed to the engine and 
identify the engine as certified for use in a certain regulatory 
subcategory of vehicle (i.e., MHD, etc).
    The vehicle will also have a label listing the manufacturer of the 
vehicle, vehicle family (and subfamily, if applicable), regulatory 
subcategory, date of manufacture, compliance statement, FEL, and 
emission control system identifiers. The required content of this label 
is consistent with the label description provided earlier for Class 7 
and 8 tractors. Since LRR tires are expected to be the primary means 
for vehicles to comply, it is expected that LRR tires will be the only 
component identified as part of the emission control system on the 
label. For tires to qualify as low rolling resistance (for purposes of 
this vocational vehicle label), they need to have a coefficient of 
rolling resistance at or below 7.7 kg/metric ton. In addition, if any 
other emission related components are present, such as hybrid 
powertrains, key components will also need to be specified on the 
label. Like the engine label, this will need to be permanently affixed 
to the vehicle in an area that is clearly visible to the owner/
operator. At the time of certification, manufacturers will be required 
to submit an example of their vehicle emission control label such that 
EPA can verify that all critical elements are present. In addition to 
the label, manufacturers will also need to describe where the unique 
vehicle identification number and date of production can be found on 
the vehicle.
(3) Other Certification Issues
Warranty
    As with other heavy-duty engine and vehicle regulatory categories, 
vocational vehicle chassis manufacturers would be required to warrant 
their product to be free from defects that would result in 
noncompliance with emission standards. This warranty also covers the 
failure of emission related components for the warranty period of the 
vehicle. For vocational vehicles, this primarily applies to tires.
    Manufacturers of chassis for vocational vehicles would be required 
to warrant tires to be free from defects at the time of initial sale. 
As with Class 7 and 8 combination tractors, we expect the chassis 
manufacturer to only warrant the original tires against manufacturing 
or design-related defects. This tire warranty would not cover 
replacement tires or damage from road hazards or improper inflation.
    As with Class 7 and 8 combination tractors, all warranty 
documentation would be submitted to EPA at the time of certification. 
This should include the warranty statement provided to the owner/
operator, description of the service repair network, list of covered 
components (both conventional and high-cost), and length of coverage.
EPA Certification Fees
    Similar to engine and tractor-trailer vehicle certification, the 
agency will assess certification fees for vocational vehicles. The 
proceeds from these fees are used to fund the compliance and 
certification activities related to GHG regulation for this industry 
segment. In addition to the certification process, other activities 
funded by certification fees include EPA-administered in-use testing, 
selective enforcement audits, and confirmatory testing. At this point, 
the exact costs associated with the heavy-duty vehicle GHG compliance 
are not well known. EPA will assess its compliance program associated 
with this program and assess the appropriate level of fees. We 
anticipate that fees will be applied based on certification families, 
following the light-duty vehicle approach.
Maintenance
    Vehicle manufacturers are required to outline a maintenance 
schedule that ensures the emission control system remains functional 
throughout the useful life of the vehicle. For vocational vehicles, 
this largely involves ensuring that customers have sufficient 
information to purchase replacement tires that meet or exceed original 
equipment specifications. As with Class

[[Page 57288]]

7 and 8 tractors, we believe that this information should be included 
in the owner's manual to the vehicle. This statement must be submitted 
to EPA at the time of certification to verify that the customer indeed 
has enough information to purchase the correct replacement tires.

F. General Regulatory Provisions

(1) Statutory Prohibited Acts
    Section 203 of the CAA describes acts that are prohibited by law. 
This section and associated regulations apply equally to the greenhouse 
gas standards as to any other regulated emission. Acts that are 
prohibited by section 203 of the CAA include the introduction into 
commerce or the sale of an engine or vehicle without a certificate of 
conformity, removing or otherwise defeating emission control equipment, 
the sale or installation of devices designed to defeat emission 
controls, and other actions. In addition, vehicle manufacturers, or any 
other party, may not make changes to the certified engine that would 
result in it not being in the certified configuration.
    EPA will apply Sec.  86.1854-12 to heavy-duty vehicles and engines; 
this codifies the prohibited acts spelled out in the statute. Although 
it is not legally necessary to repeat what is in the CAA, EPA believes 
that including this language in the regulations provides clarity and 
improves the ease of use and completeness of the regulations. Since 
this change merely codifies provisions that already apply, there is no 
burden associated with the change.
(2) Regulatory Amendments Related to Heavy-Duty Engine Certification
    We are adopting the new engine-based greenhouse gas emissions 
standards in 40 CFR part 1036 and the new vehicle-based standards in 40 
CFR part 1037. We are continuing to rely on 40 CFR parts 85 and 86 for 
conventional certification and compliance provisions related to 
criteria pollutants, but the final regulations include a variety of 
amendments that will affect the provisions that apply with respect to 
criteria pollutants. We are not intending to change the stringency of, 
or otherwise substantively change any existing standards.
    The introduction of new parts in the CFR is part of a long-term 
plan to migrate all the regulatory provisions related to highway and 
nonroad engine and vehicle emissions to a portion of the CFR called 
Subchapter U, which consists of 40 CFR parts 1000 through 1299. We have 
already adopted emission standards, test procedures, and compliance 
provisions for several types of engines in 40 CFR parts 1033 through 
1074. We intend eventually to capture all the regulatory requirements 
related to heavy-duty highway engines and vehicles in these new parts. 
Moving regulatory provisions to the new parts allows us to publish the 
regulations in a way that is better organized, reflects updates to 
various certification and compliance procedures, provides consistency 
with other engine programs, and is written in plain language. We have 
already taken steps in this direction for heavy-duty highway engines by 
adopting the engine-testing procedures in 40 CFR part 1065 and the 
provisions for selective enforcement audits in 40 CFR part 1068.
    EPA sought comment on drafting changes and additions. This 
solicitation related solely to the appropriate migration, translation, 
and enhancement of existing provisions. EPA did not solicit comment on 
the substance of these existing rules, and did not amend, reconsider, 
or otherwise re-examine these provisions' substantive effect.
    The rest of this section describes the most significant of these 
final redrafting changes. The proposal includes several changes to the 
certification and compliance procedures, including the following:
     We are requiring that engine manufacturers provide 
installation instructions to vehicle manufacturers (see Sec.  
1036.130). We expect this is already commonly done; however, the 
regulatory language spells out a complete list of information we 
believe is necessary to properly ensure that vehicle manufacturers 
install engines in a way that is consistent with the engine's 
certificate of conformity.
     Sec.  1036.30, Sec.  1036.250, and Sec.  1036.825 spell 
out several detailed provisions related to keeping records and 
submitting information to us.
     We wrote the greenhouse gas regulations to divide heavy-
duty engines into ``spark-ignition'' and ``compression-ignition'' 
engines, rather than ``Otto-cycle'' and ``diesel'' engines, to align 
with our terminology in all our nonroad programs. This will likely 
involve no effective change in categorizing engines except for natural 
gas engines. To address this concern, we are including a provision in 
Sec.  1036.150 to allow manufacturers to meet standards for spark-
ignition engines if they were regulated as Otto-cycle engines in 40 CFR 
part 86, and vice versa.
     Sec.  1036.205 describes a new requirement for imported 
engines to describe the general approach to importation (such as 
identifying authorized agents and ports of entry), and identifying a 
test lab in the United States where EPA can perform testing on 
certified engines. These steps are part of our ongoing effort to ensure 
that we have a compliance and enforcement program that is as effective 
for imported engines as for domestically produced engines. We have 
already adopted these same provisions for several types of nonroad 
engines.
     Sec.  1036.210 specifies a process by which manufacturers 
are able to get preliminary approval for EPA decisions for questions 
that require lead time for preparing an application for certification. 
This might involve, for example, preparing a plan for durability 
testing, establishing engine families, identifying adjustable 
parameters, and creating a list of scheduled maintenance items.
     Sec.  1036.225 describes how to amend an application for 
certification.
     We are revising 40 CFR 85.1701 to apply the exemption 
provisions described in 40 CFR part 1068 to heavy-duty highway engines 
starting in 2014. Manufacturers may optionally use the exemption 
provisions from part 1068 earlier. This involves only very minor 
changes in the terms and conditions associated with the various types 
of exemptions. This change will help us to implement a consistent 
compliance program for all engine and vehicle categories. We are 
similarly revising 40 CFR 85.1511 to reference the importation-related 
exemptions in part 1068 for all motor vehicles and motor vehicle 
engines.
     We are finalizing a provision allowing manufacturers to 
use the defect reporting provisions of 40 CFR part 1068 instead of 
those in 40 CFR part 85. This involves setting thresholds for 
investigating and reporting defects based on defect rates rather than 
absolute numbers of defects. Once we gain more experience with applying 
the defect-reporting provisions in 40 CFR part 1068 for motor vehicles, 
we will consider making those provisions mandatory, including any 
appropriate adjustments.
    In addition, we are revising 40 CFR 1068.210 and 1068.325 to 
address a concern raised by engine manufacturers. The provisions for 
importing engines under a temporary exemption disallow selling exempted 
engines even though some of the situations addressed depend on engine 
sales (such as delegated assembly). We have added clarifying language 
to the individual exemptions to describe whether or how engines may be 
sold or leased. In the case of the testing exemption in Sec.  1068.210, 
this involves a further change to specify how

[[Page 57289]]

a manufacturer must track the status and final disposition of exempted 
engines or equipment. We are also making a small change to the testing 
exemption to remove the administrative step of requiring an exchange of 
signed documents for the exemption to be effective. This will 
streamline the process for the testing exemption and make it more like 
that for other types of exemptions.
(3) Test Procedures for Measuring Emissions From Heavy-Duty Vehicles
    We are finalizing a new part 1066 that contains general chassis-
based test procedures for measuring emissions from a variety of 
vehicles, including vehicles over 14,000 pounds GVWR. However, we are 
not finalizing application of these procedures broadly at this time. 
The test procedures in 40 CFR part 86 continue to apply for vehicles 
under 14,000 pounds GVWR. The final part 1066 procedures applies only 
for any testing that would be required for larger vehicles. This could 
include ``A to B'' hybrid vehicle testing, coastdown testing, and 
potentially limited innovative technology testing. Nevertheless, we 
will likely consider in the future applying these procedures also for 
other heavy-duty vehicle testing and for light-duty vehicles, highway 
motorcycles, and/or nonroad recreational vehicles that rely on chassis-
based testing.
    As noted above, engine manufacturers are already using the test 
procedures in 40 CFR part 1065 instead of those originally adopted in 
40 CFR part 86. The new procedures are written to apply generically for 
any type of engine and include the current state of technology for 
measurement instruments, calibration procedures, and other practices. 
We are finalizing the chassis-based test procedures in part 1066 to 
have a similar structure.
    The final procedures in part 1066 reference large portions of part 
1065 to align test specifications that apply equally to engine-based 
and vehicle-based testing, such as CVS and analyzer specifications and 
calibrations, test fuels, calculations, and definitions of many terms. 
Since several highway engine manufacturers were involved in developing 
the full range of specified procedures in part 1065, we are confident 
that many of these provisions are appropriate without modification for 
vehicle testing.
    The remaining test specifications needed in part 1066 are mostly 
related to setting up, calibrating, and operating a chassis 
dynamometer. This also includes the coastdown procedures that are 
required for establishing the dynamometer load settings to ensure that 
the dynamometer accurately simulates in-use driving.
    Current testing requirements related to dynamometer specifications 
rely on a combination of regulatory provisions, EPA guidance documents, 
and extensive know-how from industry experience that has led to a good 
understanding of best practices for operating a vehicle in the 
laboratory to measure emissions. We attempted in this rulemaking to 
capture this range of material, organizing these specifications and 
verification and calibration procedures to include a complete set of 
provisions to ensure that a dynamometer meeting these specifications 
would allow for carefully controlled vehicle operation such that 
emission measurements are accurate and repeatable.
    The procedures are written with the understanding that heavy-duty 
highway manufacturers have, and need to have, single-roll electric 
dynamometers for testing. We are aware that this is not the case for 
other applications, such as all-terrain vehicles. We are not adopting 
specific provisions for testing with hydrokinetic dynamometers, we are 
already including a provision acknowledging that we may approve the use 
of dynamometers meeting alternative specifications if that is 
appropriate for the type of vehicle being tested and for the level of 
stringency represented by the corresponding emission standards.
    Drafting a full set of test specifications highlights the mixed use 
of units for testing. Some chassis-based standards and procedures are 
written based largely on the International System of Units (SI), such 
as gram per kilometer (g/km) standards and kilometers per hour (kph) 
driving, while others are written based largely on English units (g/
mile standards and miles per hour driving). The proposal includes a mix 
of SI and English units with instructions about converting units 
appropriately. However, most of the specifications and examples are 
written in English units. While this seems to be the prevailing 
practice for testing in the United States, we understand that vehicle 
testing outside the United States is almost universally done in SI 
units. In any case, dynamometers are produced with the capability of 
operating in either English or SI units. We believe there would be a 
substantial advantage toward the goal of achieving globally harmonized 
test procedures if we would write the test procedures based on SI 
units. This would also in several cases allow for more straightforward 
calculations, and reduced risk of rounding errors. For comparison, part 
1065 is written almost exclusively in SI units. We sought comment on 
the use of units throughout part 1066. At this time we are not 
finalizing changes from our current approach.
    A fundamental obstacle toward using SI units is the fact that some 
duty cycles are specified based on speeds in miles per hour. To address 
this, it would be appropriate to convert the applicable driving 
schedules to meter-per-second (m/s) values. Converting speeds to the 
nearest 0.01 m/s would ensure that the prescribed driving cycle does 
not change with respect to driving schedules that are specified to the 
nearest 0.1 mph. The regulations would include the appropriate mph (or 
kph) speeds to allow for a ready understanding of speed values (see 40 
CFR part 1037, Appendix I). This would, for example, allow for drivers 
to continue to follow a mph-based speed trace. The 2 mph 
tolerance on driving speeds could be converted to 1.0 m/s, 
which corresponds to an effective speed tolerance of 2.2 
mph. This may involve a tightening or loosening of the existing speed 
tolerance, depending on whether manufacturers used the full degree of 
flexibility allowed for a mph tolerance value that is specified without 
a decimal place. Similarly, the Cruise cycles for heavy-duty vehicles 
could be specified as 24.50.5 m/s (54.81.1 mph) 
and 29.00.5 m/s (64.91.1 mph).
(4) Compliance Reports
(a) Early Model Year Data
    This information is the same as for tractors early model year data 
in Section V.D(4)(a).
(b) Final Reports
    This information is the same as for tractors final reports in 
Section V.D(4)(b).
(c) Additional Required Information
    Table V-7 below provides a summary of the types of requests, 
required application submission dates and the EPA and NHTSA regulations 
that apply.

[[Page 57290]]

                            Table V-7--Summary of Required Information for Compliance
----------------------------------------------------------------------------------------------------------------
                                                                                                       NHTSA
            Submission                    Applies to        Required submissions  EPA regulation    regulation
                                                                    date             reference       reference
----------------------------------------------------------------------------------------------------------------
Small business exemptions.........  Vehicle or engine      Before introducing               Sec.    Sec.   535.8
                                     manufacturers          any excluded vehicle        1037.150
                                     meeting the Small      into U.S. commerce.
                                     Business
                                     Administration (SBA)
                                     size criteria of a
                                     small business as
                                     described in 13 CFR
                                     121.201.
Incentives for early introduction.  The provisions apply   EPA must be notified             Sec.    Sec.   535.8
                                     with respect to        before the                  1037.150
                                     tractors and           manufacturer submits
                                     vocational vehicles    it applications for
                                     produced in model      certificates of
                                     years before 2014.     conformity.
Air condition leakage exemption     Vocational Vehicles    EPA must be notified             Sec.    Sec.   535.8
 for vocational vehicles.            excluded from Sec.     before the                  1037.150
                                     1037.115.              manufacturer submits
                                                            it applications for
                                                            certificates of
                                                            conformity.
Model year 2014 N2O standards.....  Manufacturers that     EPA must be notified             Sec.    Sec.   535.8
                                     choose to show         before the                  1037.150
                                     compliance with the    manufacturer submits
                                     MY 2014 N2O            it applications for
                                     standards requesting   certificates of
                                     to use an              conformity.
                                     engineering analysis.
Exemption for electric vehicles...  All electric vehicles  End of December prior            Sec.    Sec.   535.8
                                     are deemed to have     to model year.              1037.150
                                     zero exhaust
                                     emissions of CO2,
                                     CH4, and N2O.
Off-road exemption................  Manufacturers wanting  EPA must be notified             Sec.    Sec.   535.8
                                     to exclude             before the                  1037.150
                                     vocational vehicles    manufacturer submits
                                     from vehicle           it applications for
                                     standards.             certificates of
                                                            conformity.
Exemption from EOY reports........  Manufactures with      90-days after the                Sec.    Sec.   535.8
                                     surplus credits at     calendar year ends.         1037.730
                                     the end of the model
                                     year.
----------------------------------------------------------------------------------------------------------------

G. Penalties

(1) Overview
    In the NPRM, NHTSA proposed to assess civil penalties for non-
compliance with fuel consumption standards. NHTSA's authority under 
EISA, as codified at 49 U.S.C. 32902(k), requires the agency to 
determine appropriate measurement metrics, test procedures, standards, 
and compliance and enforcement protocols for HD vehicles. NHTSA 
interprets its authority to develop an enforcement program to include 
the authority to determine and assess civil penalties for noncompliance 
that would impose penalties based on the following discussions.
    In cases of noncompliance, the agency explained in the NPRM that it 
would establish civil penalties based on consideration of the following 
factors:
 Gravity of the violation.
 Size of the violator's business.
 Violator's history of compliance with applicable fuel 
consumption standards.
 Actual fuel consumption performance related to the applicable 
standard.
 Estimated cost to comply with the regulation and applicable 
standard.
 Quantity of vehicles or engines not complying.
 Civil penalties paid under CAA section 205 (42 U.S.C. 7524) 
for non-compliance for the same vehicles or engines.
    NHTSA proposed to consider these factors in determining civil 
penalties in order to help ensure, given the agency's wide discretion, 
that penalties would be fair and appropriate, and not duplicative of 
EPA penalties. The NPRM expressly stated that neither agency intended 
to impose duplicative civil penalties, and that both agencies would 
give consideration to civil penalties imposed by the other in the case 
of non-compliance with its own regulations. See NPRM at 74280.
    EMA, Volvo, the Truck Renting and Leasing Association (TRALA), and 
Navistar nevertheless commented that a dual enforcement scheme with 
separate NHTSA and EPA penalties could result in duplicative penalties, 
as manufacturers could be assessed penalties twice for the same 
violation.
    The possibility of more than one prosecution or enforcement action 
arising from the same overall body of facts does not present a novel 
issue. It commonly arises where there is overlapping jurisdiction, such 
as where the federal government and a state government have 
jurisdiction. The issue of multiple or sequential prosecutions may be 
addressed as a matter of administrative policy and discretion.\319\
---------------------------------------------------------------------------

    \319\ A well-known example is the Department of Justice's petite 
policy, an internal guide on whether to pursue federal prosecution 
after a state prosecution. The petite policy is considered ``merely 
a housekeeping provision,'' and prosecution remains entirely within 
the Department's discretion. U.S. v. Barrett, 496 F.3d 1079, 1120 
(10th Cir. 2007).
---------------------------------------------------------------------------

    Both NHTSA and EPA are charged with regulating medium-duty and 
heavy-duty trucks; NHTSA regulates them under EISA and EPA regulates 
them under the CAA. Both agencies also have compliance review and 
enforcement responsibilities for their respective regulatory 
requirements. The same set of underlying facts may result in a 
violation of EISA and a violation of the CAA. The agencies recognize 
the above concerns, and intend to address them through appropriate 
consultation. The details of the consultation and coordination between 
the agencies regarding enforcement will be set forth in a memorandum of 
understanding to be developed by EPA and NHTSA.
    NHTSA believes that the above description adequately describes the 
process by which civil penalties may be assessed by both agencies. 
Therefore, for the final action, penalties for a violation of a fuel 
consumption standard will be based on the gravity of the violation, the 
size of the violator's business, the violator's history of compliance 
with applicable fuel consumption standards, the actual fuel consumption 
performance related to the applicable standard, the estimated cost to 
comply with the regulation and applicable standard, and the quantity of 
vehicles or engines not complying. The collaborative enforcement 
process will ensure that the total penalties assessed will not be 
duplicative or excessive.
    NHTSA would also like to clarify that the ``estimated cost to 
comply with the regulation and applicable standard,'' will be used to 
ensure that penalties for non-compliance will not be less than the cost 
of compliance. It would be contrary to the purpose of the regulation

[[Page 57291]]

for the penalty scheme to incentivize noncompliance.
    The final civil penalty amount NHTSA could impose would not exceed 
the limit that EPA is authorized to impose under the CAA. The potential 
maximum civil penalty for a manufacturer would be calculated as follows 
in Equation V-1:

Equation V-1: Aggregate Maximum Civil Penalty

Aggregate Maximum Civil Penalty for a Non-Compliant Regulatory Category 
= (CAA Limit) x (production volume within the regulatory category)
    EPA has occasionally in the past conducted rulemakings to provide 
for nonconformance penalties-- monetary penalties that allow a 
manufacturer to sell engines or vehicles that do not meet an emissions 
standard. Nonconformance penalties are authorized for heavy-duty 
engines and vehicles under section 206(g) of the CAA. Three basic 
criteria have been established by rulemaking for determining the 
eligibility of emissions standards for nonconformance penalties in any 
given model year: (1) The emissions standard in question must become 
more difficult to meet, (2) substantial work must be required in order 
to meet the standard, and (3) a technological laggard must be likely to 
develop (40 CFR 86.1103-87). A technological laggard is a manufacturer 
who cannot meet a particular emissions standard due to technological 
(not economic) difficulties and who, in the absence of nonconformance 
penalties, might be forced from the marketplace. The process to 
determine if these criteria are met and to establish penalty amounts 
and conditions is carried out via rulemaking, as required by the CAA. 
The CAA (in section 205) also lays out requirements for the assessment 
of civil penalties for noncompliance with emissions standards.
    As discussed in detail in Section III, the agencies have determined 
that the final GHG and fuel consumption standards are readily feasible, 
and we do not believe a technological laggard will emerge in any sector 
covered by these final standards. In addition to the standards being 
premised on use of already-existing, cost-effective technologies, there 
are a number of flexibilities and alternative standards built into the 
proposal. However, in the case of potential non-conformance, civil 
penalties will ensure that adequate deterrence for non-conformance 
exists.
(2) NHTSA's Penalty Process
    NHTSA proposed a detailed enforcement process in the NPRM. As 
proposed, enforcement would begin with a notice of violation, after 
which the respondent may either pay the penalty proposed in the notice 
of violation or dispute it by requesting an agency hearing. For a party 
that did not pay the proposed penalty or request a hearing within 30 
days of the notice of violation, a finding of default would be entered 
and the penalty set forth in the notice of violation assessed. If a 
hearing is timely requested, the respondent would receive written 
notice of the time, date and location of the hearing. The respondent 
would have the right to counsel and to examine, respond to and rebut 
evidence presented by the Chief Counsel. If civil penalties greater 
than $250,000,000 were assessed in the Hearing Officer's final order, 
that order would contain a statement advising the party of the right to 
appeal to the NHTSA Administrator. In the event of a timely appeal, the 
decision of the Administrator would be a final agency action. This 
structure was intended to ensure that a party was afforded ample 
opportunity to be heard.
    Several manufacturers commented that NHTSA's penalty procedures 
should be more formal than was proposed in the NPRM. EMA, Volvo and 
Navistar commented that the penalty procedures should be subject to the 
Administrative Procedure Act (APA) review requirements. EMA, Volvo and 
Navistar, and TRALA commented that the penalty procedures violated due 
process requirements. EMA argued that NHTSA must expressly grant a 
right to judicial review, and EMA and Navistar argued that the absence 
of an administrative appeals process for penalties under $250,000,000 
would violate due process. Volvo faulted NHTSA for not classifying the 
hearing officer's decision as a final agency action, and stated that 
specifications regarding who could be a hearing officer should align 
with those specified for the light-duty program, which was laid out in 
49 CFR 511.3.
    As noted in the NPRM, the APA administrative hearing requirements 
of Sections 554, 556, and 557 are not required where formal procedures 
are not required by statute (generally, the organic statute must 
provide that the administrative proceeding must be an adjudication, 
determined on the record after the opportunity for an agency hearing, 
sometimes referenced as an opportunity for hearing on the record). See 
e.g., 5 U.S.C. Section 554. Where a formal adjudication is not required 
by statute, in general, agencies adopt and apply informal processes. 
While the compliance, civil penalty and appeals provisions of 49 U.S.C. 
Sections 32911 and 32914 require formal adjudication in accordance with 
APA requirements, those sections only apply to the light-duty fuel 
economy program. In contrast, for the heavy-duty program of Section 
32902(k), the Congress did not require formal adjudication in 
accordance with the APA. Therefore, informal adjudication procedures 
may be applied. NHTSA will not adopt the procedures of by 5 U.S.C. 
Sections 554, 556, or 557 for the final rule.
    While the APA requirements for formal hearing procedures do not 
apply to NHTSA's enforcement under Section 32902(k), due process 
requirements do apply. NHTSA believes that formal procedures are 
neither required by statute nor necessary for this enforcement process 
to meet due process requirements. NHTSA expects that the cases will not 
be complex. In general, there will be one or two issues: (1) Compliance 
with the regulations and, if not, (2) the appropriate civil penalty. 
Compliance likely will involve narrow technical questions under the 
regulations being adopted today. Non-compliance with applicable fuel 
consumption standards will be determined by utilizing the certified and 
reported CO2 emissions and fuel consumption data provided by 
EPA as described in this part, and after considering all the 
flexibilities available under Section 535.7. Much of the evidence will 
be materials developed by the respondent. There likely will not be wide 
ranging issues. The parties will have ample opportunity to present 
their positions. A hearing officer can readily address the sorts of 
questions that are likely to arise. Second, if there is a 
noncompliance, there will be the question of the appropriate penalty. 
NHTSA's regulations contain factors to be considered in assessing 
penalties. Again, the parties will have ample opportunity to present 
their positions. Ultimately, the agency's final decision must be 
sufficiently reasoned to withstand judicial review, based on the 
arbitrary and capricious standard.
    To address commenters' concerns about the process provided, NHTSA 
made several adjustments and clarifications in the final rule. The 
final rule provides that there will be a written decision of the 
Hearing Officer, and the assessment of a civil penalty by a hearing 
officer shall be set forth in an accompanying final order. Together, 
these constitute the final agency action. NHTSA has also revisited the 
minimum penalty level for an administrative appeal to the NHTSA 
Administrator and decided to lower the level significantly, to 
$1,000,000. This provides a second level of review. NHTSA believes this

[[Page 57292]]

will promote an efficient use of administrative remedies and a further 
opportunity to be heard at the administrative level. Of course, if a 
party files an appeal with the NHTSA Administrator, the Hearing 
Officer's decision and order at that juncture shall no longer be final 
agency action.
    NHTSA has considered the specifications of the Hearing Officer and 
determined that they are adequate for informal agency hearings of this 
nature. However, the agency will add a clarification to the final rule 
that specifies that the Hearing Officer will be appointed by the 
Administrator. Further, in addition to having no prior connection with 
the case and no responsibility, direct or supervisory, for the 
investigation of cases referred for the assessment of civil penalties, 
the Hearing Officer will have no duties related to the light-duty fuel 
economy or medium- and heavy-duty fuel efficiency programs.
    NHTSA has also considered EMA's comment that a right to judicial 
review must be specified in the regulatory text. The agency does not 
agree with this concern. Parties, of course, cannot confer 
jurisdiction; only Congress can do so. Whitman v. Department of 
Transportation, 547 U.S. 512, 514 (2006); Weinberger v. Bentex 
Pharmaceuticals, Inc., 412 U.S. 645, 652 (1973). Moreover, judicial 
review of a final agency action is presumed. United States v. Fausto, 
484 U.S. 439, 452 (1998), citing Abbot Laboratories v. Gardner, 387 
U.S. 136, 140 (1967). See generally, 28 U.S.C. Section 1331. Therefore, 
NHTSA has determined that the right to judicial review does not need to 
be specified in the regulatory text.

VI. How will this program impact fuel consumption, GHG emissions, and 
climate change?

A. What methodologies did the agencies use to project GHG emissions and 
fuel consumption impacts?

    EPA and NHTSA used EPA's official mobile source emissions inventory 
model named Motor Vehicle Emissions Simulator (MOVES2010),\320\ to 
estimate emission and fuel consumption impacts of these final rules. 
MOVES has the capability to take in user inputs to modify default data 
to better estimate emissions for different scenarios, such as different 
regulatory alternatives, state implementation plans (SIPs), geographic 
locations, vehicle activity, and microscale projects.
---------------------------------------------------------------------------

    \320\ MOVES homepage: http://www.epa.gov/otaq/models/moves/index.htm. Version MOVES2010 was used for emissions impacts analysis 
for this action. Current version as of September 14, 2010 is an 
updated version named MOVES2010a, available directly from the MOVES 
homepage. To replicate results from this action, MOVES2010 must be 
used.
---------------------------------------------------------------------------

    The agencies performed multiple MOVES runs to establish reference 
case and control case emission inventories and fuel consumption values. 
The agencies ran MOVES with user input databases that reflected 
characteristics of the final rules, such as emissions improvements and 
recent sales projections. Some post-processing of the model output was 
required to ensure proper results. The agencies ran MOVES for non-GHGs, 
CO2, CH4, and N2O for calendar years 
2005, 2018, 2030, and 2050. Additional runs were performed for just the 
three greenhouse gases and for fuel consumption for every calendar year 
from 2014 to 2050, inclusive, which fed the economy-wide modeling, 
monetized greenhouse gas benefits estimation, and climate impacts 
analyses.
    The agencies also used MOVES to estimate emissions and fuel 
consumption impacts for the other alternatives considered and described 
in Section IX.

B. MOVES Analysis

(i) Inputs and Assumptions
    The analysis performed for the final action mirrors what was done 
for the proposal. The methods and models are the same, with differences 
lying primarily in the inputs, as a result of updates in the program, 
standards, and baseline data.
(a) Reference Run Updates
    Since MOVES2010a vehicle sales and activity data were developed 
from AEO2009, EPA first updated these data using sales and activity 
estimates from AEO2011. MOVES2010a defaults were used for all other 
parameters to estimate the reference case emissions inventories.
(b) Control Run Updates
    EPA developed additional user input data for MOVES runs to estimate 
control case inventories. To account for improvements of engine and 
vehicle efficiency, EPA developed several user inputs to run the 
control case in MOVES. As explained at proposal, since MOVES does not 
operate based on Heavy-duty FTP cycle results, EPA used the percent 
reduction in engine CO2 emissions expected due to the final 
rules to develop energy inputs for the control case runs. 75 FR at 
74280. Also, EPA used the percent reduction in aerodynamic drag and 
tire rolling resistance coefficients and reduction in average total 
running weight (gross combined weight) expected from the final rules to 
develop road load input for the control case. The sales and activity 
data updates used in the reference case were used in the control case. 
Details of all the MOVES runs, input data tables, and post-processing 
steps are available in the docket (EPA-HQ-OAR-2010-0162).
    Table VI-1 and Table VI-2 describe the estimated expected 
reductions from these final rules, which were input into MOVES for 
estimating control case emissions inventories.
---------------------------------------------------------------------------

    \321\ Section II of this preamble discusses an alternative 
engine standard for the HD diesel engines in the 2014, 2015, and 
2016 model years. To the extent that engines using this alternative 
are expected to have baseline emissions greater than the industry 
average, the reduction from the industry average projected in this 
program would be reduced.

                       Table VI-1--Estimated Reductions in Engine CO2 Emission Rates \321\
----------------------------------------------------------------------------------------------------------------
                                                                                                   CO2 reduction
                  GVWR class                                  Fuel                  Model years    from 2010 MY
----------------------------------------------------------------------------------------------------------------
HHD (Class 8a-8b).............................  Diesel..........................       2014-2016              3%
                                                                                           2017+              6%
MHD (Class 6-7) and LHD (Class 4-5)...........  Diesel..........................       2014-2016              5%
                                                                                           2017+              9%
                                                Gasoline........................           2016+              5%
----------------------------------------------------------------------------------------------------------------

[[Page 57293]]

   Table VI-2--Estimated Reductions in Rolling Resistance Coefficient, Aerodynamic Drag Coefficient, and Gross
                                                 Combined Weight
----------------------------------------------------------------------------------------------------------------
                                                              Reduction in
                                                              tire CRR from    Reduction in Cd  Weight reduction
                        Truck type                              baseline        from baseline         (lbs.)
                                                                (percent)         (percent)
----------------------------------------------------------------------------------------------------------------
Combination long-haul.....................................               9.6              12.1               400
Combination short-haul....................................               7.0               5.9               321
Straight trucks, refuse trucks, motor homes, transit                     5.0                 0                 0
 buses, and other vocational vehicles.....................
----------------------------------------------------------------------------------------------------------------

    Since nearly all HD pickup trucks and vans will be certified on a 
chassis dynamometer, the CO2 reductions for these vehicles 
will not be represented as engine and road load reduction components, 
but rather as total vehicle CO2 reductions. These estimated 
reductions are described in Table VI-3.

                Table VI-3--Estimated Total Vehicle CO2 Reductions for HD Pickup Trucks and Vans
----------------------------------------------------------------------------------------------------------------
                                                                                                  CO2 reduction
                 GVWR Class                                Fuel                  Model year       from baseline
                                                                                                    (percent)
----------------------------------------------------------------------------------------------------------------
HD Pickup Trucks and Vans...................  Gasoline......................              2014               1.5
                                                                                          2015                 2
                                                                                          2016                 4
                                                                                          2017                 6
                                                                                         2018+                10
                                              Diesel........................              2014               2.3
                                                                                          2015                 3
                                                                                          2016                 6
                                                                                          2017                 9
                                                                                         2018+                15
----------------------------------------------------------------------------------------------------------------

C. What are the projected reductions in fuel consumption and GHG 
emissions?

    EPA and NHTSA expect significant reductions in GHG emissions and 
fuel consumption from these final rules--emission reductions from both 
downstream (tailpipe) and upstream (fuel production and distribution) 
sources, and fuel consumption reductions from more efficient vehicles. 
Increased vehicle efficiency and reduced vehicle fuel consumption will 
also reduce GHG emissions from upstream sources. The following 
subsections summarize the GHG emissions and fuel consumption reductions 
expected from these final rules.
(1) Downstream (Tailpipe)
    Consistent with the proposal, EPA used MOVES to estimate downstream 
GHG inventories from these final rules. We expect reductions in 
CO2 from all heavy-duty vehicle categories. The reductions 
come from engine and vehicle improvements. EPA expects N2O 
emissions to increase very slightly because of a rebound in vehicle 
miles traveled (VMT) and because significant vehicle emissions 
reductions are not expected from these final rules. In the proposal, we 
did not account for differences in methane emissions from use of 
auxiliary power units (APUs) during extended idling from sleeper cab 
combination tractors. After accounting for these differences, EPA 
expects methane emissions to decrease primarily due to differences in 
hydrocarbon emission characteristics between on-road diesel engines and 
APUs. The amount of methane emitted as a fraction of total hydrocarbons 
is significantly less for APUs than for diesel engines equipped with 
diesel particulate filters. Overall, downstream GHG emissions will be 
reduced significantly and are described in the following subsections.
    For CO2 and fuel consumption, the total energy 
consumption ``pollutant'' was run in MOVES rather than CO2 
itself. The energy was converted to fuel consumption based on fuel 
heating values assumed in the Renewable Fuels Standard and used in the 
development of MOVES emission and energy rates. These values are 
117,250 kJ/gallon for gasoline blended with ten percent ethanol (E10) 
\322\ and 138,451 kJ/gallon for diesel.\323\ To calculate 
CO2, the agencies assumed a CO2 content of 8,576 
g/gallon for E10 and 10,180 g/gallon for diesel. Table VI-4 shows the 
fleet-wide GHG reductions and fuel savings from reference case to 
control case through the lifetime of model year 2014 through 2018 
heavy-duty vehicles. Table VI-5 shows the downstream GHG emissions 
reductions and fuel savings in 2018, 2030, and 2050. The analysis 
follows what was done for the proposal. We did not receive comments 
indicating that this analysis was inappropriate or insufficient for 
estimating downstream emissions impacts of this program.
---------------------------------------------------------------------------

    \322\ Renewable Fuels Standards assumptions of 115,000 BTU/
gallon gasoline (E0) and 76,330 BTU/gallon ethanol (E100) weighted 
90% and 10%, respectively, and converted to kJ at 1.055 kJ/BTU.
    \323\ MOVES2004 Energy and Emission Inputs. EPA420-P-05-003, 
March 2005. http://www.epa.gov/otaq/models/ngm/420p05003.pdf.

[[Page 57294]]

  Table VI-4--Model Year 2014 Through 2018 Lifetime GHG Reductions and
                Fuel Savings by Heavy-Duty Truck Category
------------------------------------------------------------------------
                                 Downstream GHG
                                reductions  (MMT        Fuel Savings
                                     CO2eq)           (billion gallons)
------------------------------------------------------------------------
HD pickups/vans.............                    18                   1.9
Vocational..................                    24                   2.4
Combination short-haul (Day                     50                   4.9
 cabs)......................
Combination long-haul                          135                  12.9
 (Sleeper cabs).............
------------------------------------------------------------------------

         Table VI-5--Annual Downstream GHG Emissions Reductions and Fuel Savings in 2018, 2030, and 2050
----------------------------------------------------------------------------------------------------------------
                                                   Downstream GHG
                                                  reductions  (MMT       Diesel Savings       Gasoline Savings
                                                       CO2eq)           (million gallons)     (million gallons)
----------------------------------------------------------------------------------------------------------------
2018..........................................                    22                 2,123                    59
2030..........................................                    61                 5,670                   349
2050..........................................                    89                 8,158                   522
----------------------------------------------------------------------------------------------------------------

(2) Upstream (Fuel Production and Distribution)
    Using the same approach as used in the NPRM, the upstream GHG 
emission reductions associated with the production and distribution of 
fuel were projected using emission factors from DOE's ``Greenhouse 
Gases, Regulated Emissions, and Energy Use in Transportation'' 
(GREET1.8) model, with some modifications consistent with the Light-
Duty 2012-2016 MY vehicle rule. More information regarding these 
modifications can be found in the RIA Chapter 5. These estimates 
include both international and domestic emission reductions, since 
reductions in foreign exports of finished gasoline and/or crude make up 
a significant share of the fuel savings resulting from the GHG 
standards. Thus, significant portions of the upstream GHG emission 
reductions will occur outside of the United States; a breakdown and 
discussion of projected international versus domestic reductions is 
included in the RIA Chapter 5. GHG emission reductions from upstream 
sources can be found in Table VI-6.

                  Table VI-6--Annual Upstream GHG Emissions Reductions in 2018, 2030, and 2050
----------------------------------------------------------------------------------------------------------------
                                                                                                 Total GHG  (MMT
                                             CO2  (MMT)     CH4  (MMT CO2eq)  N2O  (MMT CO2eq)       CO2eq)
----------------------------------------------------------------------------------------------------------------
2018....................................               5.1               0.9              0.02               6.0
2030....................................              12.2               1.9              0.06              14.2
2050....................................              16.4               2.5              0.08              19.0
----------------------------------------------------------------------------------------------------------------

(3) HFC Emissions
    Based on projected HFC emission reductions due to the final AC 
leakage standards, EPA estimates the HFC reductions to be 120,000 
metric tons of CO2eq in 2018, 440,000 metric tons of 
CO2eq emissions in 2030 and 600,000 metric tons 
CO2eq in 2050, as detailed in RIA Chapter 5.3.4.
(4) Total (Upstream + Downstream + HFC)
    Table VI-7 combines downstream results from Table VI-5, upstream 
results Table VI-6, and HFC results to show total GHG reductions for 
calendar years 2018, 2030, and 2050.

  Table VI-7--Annual Total GHG Emissions Reductions in 2018, 2030, and
                                  2050
------------------------------------------------------------------------
                                                         GHG reductions
                                                           (MMT CO2eq)
------------------------------------------------------------------------
2018..................................................                29
2030..................................................                76
2050..................................................               108
------------------------------------------------------------------------

D. Overview of Climate Change Impacts From GHG Emissions

    Once emitted, GHGs that are the subject of this regulation can 
remain in the atmosphere for decades to millennia, meaning that 1) 
their concentrations become well-mixed throughout the global atmosphere 
regardless of emission origin, and 2) their effects on climate are long 
lasting. GHG emissions come mainly from the combustion of fossil fuels 
(coal, oil, and gas), with additional contributions from the clearing 
of forests and agricultural activities. Transportation activities, in 
aggregate, are the second largest contributor to total U.S. GHG 
emissions (27 percent of total emissions) despite a decline in 
emissions from this sector during 2008.\324\
---------------------------------------------------------------------------

    \324\ U.S. EPA (2010) Inventory of U.S. Greenhouse Gas Emissions 
and Sinks: 1990-2007. EPA-430-R-10-006, Washington, DC.
---------------------------------------------------------------------------

    This section provides a summary of observed and projected changes 
in GHG emissions and associated climate change impacts. The source 
document for the section below is the Technical Support Document (TSD) 
\325\ for EPA's Endangerment and Cause or Contribute Findings Under the 
Clean Air Act (74 FR 66496, December 15, 2009). Below is the Executive 
Summary of the TSD which provides technical support for the 
endangerment and cause or contribute analyses concerning GHG emissions 
under section 202(a) of the CAA. The TSD reviews observed and

[[Page 57295]]

projected changes in climate based on current and projected atmospheric 
GHG concentrations and emissions, as well as the related impacts and 
risks from climate change that are projected in the absence of GHG 
mitigation actions, including this program and other U.S. and global 
actions. The TSD was updated and revised based on expert technical 
review and public comment as part of EPA's rulemaking process for the 
final Endangerment Findings. The key findings synthesized here and the 
information throughout the TSD are primarily drawn from the assessment 
reports of the Intergovernmental Panel on Climate Change (IPCC), the 
U.S. Climate Change Science Program (CCSP), the U.S. Global Change 
Research Program (USGCRP), and NRC.\326\
---------------------------------------------------------------------------

    \325\ See Endangerment TSD, Note 10 above.
    \326\ For a complete list of core references from IPCC, USGCRP/
CCSP, NRC and others relied upon for development of the TSD for 
EPA's Endangerment and Cause or Contribute Findings See section 
1(b), specifically, Table 1.1 of the TSD Docket: EPA-HQ-OAR-2009-
0171-11645.
---------------------------------------------------------------------------

    In May 2010, the NRC published its comprehensive assessment, 
``Advancing the Science of Climate Change.'' \327\ It concluded that 
``climate change is occurring, is caused largely by human activities, 
and poses significant risks for--and in many cases is already 
affecting--a broad range of human and natural systems.'' Furthermore, 
the NRC stated that this conclusion is based on findings that are 
``consistent with the conclusions of recent assessments by the U.S. 
Global Change Research Program, the Intergovernmental Panel on Climate 
Change's Fourth Assessment Report, and other assessments of the state 
of scientific knowledge on climate change.'' These are the same 
assessments that served as the primary scientific references underlying 
the Administrator's Endangerment Finding. Importantly, this recent NRC 
assessment represents another independent and critical inquiry of the 
state of climate change science, separate and apart from the previous 
IPCC and USGCRP assessments.
---------------------------------------------------------------------------

    \327\ National Research Council (NRC) (2010). Advancing the 
Science of Climate Change. National Academy Press. Washington, DC.
---------------------------------------------------------------------------

(1) Observed Trends in Greenhouse Gas Emissions and Concentrations
    The primary long-lived GHGs directly emitted by human activities 
include CO2, CH4, N2O, HFCs, PFCs, and 
SF6. Greenhouse gases have a warming effect by trapping heat 
in the atmosphere that would otherwise escape to space. In 2007, U.S. 
GHG emissions were 7,150 teragrams \328\ of CO2 equivalent 
\329\ (TgCO2eq). The dominant gas emitted is CO2, 
mostly from fossil fuel combustion. Methane is the second largest 
component of U.S. emissions, followed by N2O and the 
fluorinated gases (HFCs, PFCs, and SF6). Electricity 
generation is the largest emitting sector (34 percent of total U.S. GHG 
emissions), followed by transportation (27 percent) and industry (19 
percent).
---------------------------------------------------------------------------

    \328\ One teragram (Tg) = 1 million metric tons. 1 metric ton = 
1,000 kilograms = 1.102 short tons = 2,205 pounds.
    \329\ Long-lived GHGs are compared and summed together on a 
CO2-equivalent basis by multiplying each gas by its 
global warming potential (GWP), as estimated by IPCC. In accordance 
with United Nations Framework Convention on Climate Change (UNFCCC) 
reporting procedures, the U.S. quantifies GHG emissions in the 
official U.S. greenhouse gas inventory submission to the UNFCCC 
using the 100-year time frame values for GWPs established in the 
1996 IPCC Second Assessment Report.
---------------------------------------------------------------------------

    Transportation sources under section 202(a) \330\ of the CAA 
(passenger cars, light-duty trucks, other trucks and buses, 
motorcycles, and passenger cooling) emitted 1,649 TgCO2eq in 
2007, representing 23 percent of total U.S. GHG emissions. U.S. 
transportation sources under section 202(a) made up 4.3 percent of 
total global GHG emissions in 2005,\331\ which, in addition to the 
United States as a whole, ranked only behind total GHG emissions from 
China, Russia, and India but ahead of Japan, Brazil, Germany, and the 
rest of the world's countries. In 2005, total U.S. GHG emissions were 
responsible for 18 percent of global emissions, ranking only behind 
China, which was responsible for 19 percent of global GHG emissions. 
The scope of this final action focuses on GHG emissions under section 
202(a) from heavy-duty source categories (see Section II).
---------------------------------------------------------------------------

    \330\ Source categories under Section 202(a) of the CAA are a 
subset of source categories considered in the transportation sector 
and do not include emissions from non-highway sources such as boats, 
rail, aircraft, agricultural equipment, construction/mining 
equipment, and other off-road equipment.
    \331\ More recent emission data are available for the United 
States and other individual countries, but 2005 is the most recent 
year for which data for all countries and all gases are available.
---------------------------------------------------------------------------

    The global atmospheric CO2 concentration has increased 
about 38 percent from pre-industrial levels to 2009, and almost all of 
the increase is due to anthropogenic emissions. The global atmospheric 
concentration of CH4 has increased by 149 percent since pre-
industrial levels (through 2007); and the N2O concentration 
has increased by 23 percent (through 2007). The observed concentration 
increase in these gases can also be attributed primarily to 
anthropogenic emissions. The industrial fluorinated gases, HFCs, PFCs, 
and SF6, have relatively low atmospheric concentrations but 
the total radiative forcing due to these gases is increasing rapidly; 
these gases are almost entirely anthropogenic in origin.
    Historic data show that current atmospheric concentrations of the 
two most important directly emitted, long-lived GHGs (CO2 
and CH4) are well above the natural range of atmospheric 
concentrations compared to at least the last 650,000 years. Atmospheric 
GHG concentrations have been increasing because anthropogenic emissions 
have been outpacing the rate at which GHGs are removed from the 
atmosphere by natural processes over timescales of decades to 
centuries.
(2) Observed Effects Associated With Global Elevated Concentrations of 
GHGs
    Greenhouse gases, at current (and projected) atmospheric 
concentrations, remain well below published exposure thresholds for any 
direct adverse health effects and are not expected to pose exposure 
risks (i.e., from breathing/inhalation).
    The global average net effect of the increase in atmospheric GHG 
concentrations, plus other human activities (e.g., land-use change and 
aerosol emissions), on the global energy balance since 1750 has been 
one of warming. This total net heating effect, referred to as forcing, 
is estimated to be +1.6 (+0.6 to +2.4) watts per square meter (W/m\2\), 
with much of the range surrounding this estimate due to uncertainties 
about the cooling and warming effects of aerosols. However, as aerosol 
forcing has more regional variability than the well-mixed, long-lived 
GHGs, the global average might not capture some regional effects. The 
combined radiative forcing due to the cumulative (i.e., 1750 to 2005) 
increase in atmospheric concentrations of CO2, 
CH4, and N2O is estimated to be +2.30 (+2.07 to 
+2.53) W/m\2\. The rate of increase in positive radiative forcing due 
to these three GHGs during the industrial era is very likely to have 
been unprecedented in more than 10,000 years.
    Warming of the climate system is unequivocal, as is now evident 
from observations of increases in global average air and ocean 
temperatures, widespread melting of snow and ice, and rising global 
average sea level. Global mean surface temperatures have risen by 1.3 
 0.32 [deg]F (0.74 [deg]C  0.18 [deg]C) over 
the last 100 years. Nine of the 10 warmest years on record have 
occurred since 2001. Global mean surface temperature was higher during 
the last few decades of the 20th century than during any comparable 
period during the preceding four centuries.

[[Page 57296]]

    Most of the observed increase in global average temperatures since 
the mid-20th century is very likely due to the observed increase in 
anthropogenic GHG concentrations. Climate model simulations suggest 
natural forcing alone (i.e., changes in solar irradiance) cannot 
explain the observed warming.
    U.S. temperatures also warmed during the 20th and into the 21st 
century; temperatures are now approximately 1.3 [deg]F (0.7 [deg]C) 
warmer than at the start of the 20th century, with an increased rate of 
warming over the past 30 years. Both the IPCC \332\ and the CCSP 
reports attributed recent North American warming to elevated GHG 
concentrations. In the CCSP (2008) report,\333\ the authors find that 
for North America, ``more than half of this warming [for the period 
1951-2006] is likely the result of human-caused greenhouse gas forcing 
of climate change.''
---------------------------------------------------------------------------

    \332\ Hegerl, G.C. et al. (2007) Understanding and Attributing 
Climate Change. In: Climate Change 2007: The Physical Science Basis. 
Contribution of Working Group I to the Fourth Assessment Report of 
the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, 
M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. 
Miller (eds.)]. Cambridge University Press, Cambridge, United 
Kingdom and New York, NY, USA.
    \333\ CCSP (2008) Reanalysis of Historical Climate Data for Key 
Atmospheric Features: Implications for Attribution of Causes of 
Observed Change. A Report by the U.S. Climate Change Science Program 
and the Subcommittee on Global Change Research [Randall Dole, Martin 
Hoerling, and Siegfried Schubert (eds.)]. National Oceanic and 
Atmospheric Administration, National Climatic Data Center, 
Asheville, NC, 156 pp.
---------------------------------------------------------------------------

    Observations show that changes are occurring in the amount, 
intensity, frequency and type of precipitation. Over the contiguous 
United States, total annual precipitation increased by 6.1 percent from 
1901 to 2008. It is likely that there have been increases in the number 
of heavy precipitation events within many land regions, even in those 
where there has been a reduction in total precipitation amount, 
consistent with a warming climate.
    There is strong evidence that global sea level gradually rose in 
the 20th century and is currently rising at an increased rate. It is 
not clear whether the increasing rate of sea level rise is a reflection 
of short-term variability or an increase in the longer-term trend. 
Nearly all of the Atlantic Ocean shows sea level rise during the last 
50 years with the rate of rise reaching a maximum (over 2 millimeters 
[mm] per year) in a band along the U.S. east coast running east-
northeast.
    Satellite data since 1979 show that annual average Arctic sea ice 
extent has shrunk by 4.1 percent per decade. The size and speed of 
recent Arctic summer sea ice loss is highly anomalous relative to the 
previous few thousands of years.
    Widespread changes in extreme temperatures have been observed in 
the last 50 years across all world regions, including the United 
States. Cold days, cold nights, and frost have become less frequent, 
while hot days, hot nights, and heat waves have become more frequent.
    Observational evidence from all continents and most oceans shows 
that many natural systems are being affected by regional climate 
changes, particularly temperature increases. However, directly 
attributing specific regional changes in climate to emissions of GHGs 
from human activities is difficult, especially for precipitation.
    Ocean CO2 uptake has lowered the average ocean pH 
(increased acidity) level by approximately 0.1 since 1750. Consequences 
for marine ecosystems can include reduced calcification by shell-
forming organisms, and in the longer term, the dissolution of carbonate 
sediments.
    Observations show that climate change is currently affecting U.S. 
physical and biological systems in significant ways. The consistency of 
these observed changes in physical and biological systems and the 
observed significant warming likely cannot be explained entirely due to 
natural variability or other confounding non-climate factors.
(3) Projections of Future Climate Change With Continued Increases in 
Elevated GHG Concentrations
    Most future scenarios that assume no explicit GHG mitigation 
actions (beyond those already enacted) project increasing global GHG 
emissions over the century, with climbing GHG concentrations. Carbon 
dioxide is expected to remain the dominant anthropogenic GHG over the 
course of the 21st century. The radiative forcing associated with the 
non-CO2 GHGs is still significant and increasing over time.
    Future warming over the course of the 21st century, even under 
scenarios of low-emission growth, is very likely to be greater than 
observed warming over the past century. According to climate model 
simulations summarized by the IPCC,\334\ through about 2030, the global 
warming rate is affected little by the choice of different future 
emissions scenarios. By the end of the 21st century, projected average 
global warming (compared to average temperature around 1990) varies 
significantly depending on the emission scenario and climate 
sensitivity assumptions, ranging from 3.2 to 7.2 [deg]F (1.8 to 4.0 
[deg]C), with an uncertainty range of 2.0 to 11.5 [deg]F (1.1 to 6.4 
[deg]C).
---------------------------------------------------------------------------

    \334\ Meehl, G.A. et al. (2007) Global Climate Projections. In: 
Climate Change 2007: The Physical Science Basis. Contribution of 
Working Group I to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. 
Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller 
(eds.)]. Cambridge University Press, Cambridge, United Kingdom and 
New York, NY, USA.
---------------------------------------------------------------------------

    All of the United States is very likely to warm during this 
century, and most areas of the United States are expected to warm by 
more than the global average. The largest warming is projected to occur 
in winter over northern parts of Alaska. In western, central and 
eastern regions of North America, the projected warming has less 
seasonal variation and is not as large, especially near the coast, 
consistent with less warming over the oceans.
    It is very likely that heat waves will become more intense, more 
frequent, and longer lasting in a future warm climate, whereas cold 
episodes are projected to decrease significantly.
    Increases in the amount of precipitation are very likely in higher 
latitudes, while decreases are likely in most subtropical latitudes and 
the southwestern United States, continuing observed patterns. The mid-
continental area is expected to experience drying during summer, 
indicating a greater risk of drought.
    Intensity of precipitation events is projected to increase in the 
United States and other regions of the world. More intense 
precipitation is expected to increase the risk of flooding and result 
in greater runoff and erosion that has the potential for adverse water 
quality effects.
    It is likely that hurricanes will become more intense, with 
stronger peak winds and more heavy precipitation associated with 
ongoing increases of tropical sea surface temperatures. Frequency 
changes in hurricanes are currently too uncertain for confident 
projections.
    By the end of the century, global average sea level is projected by 
IPCC \335\ to rise between 7.1 and 23 inches (18 and 59 centimeter 
[cm]), relative to around 1990, in the absence of increased dynamic ice 
sheet loss. Recent rapid changes at the edges of the Greenland and West 
Antarctic ice sheets

[[Page 57297]]

show acceleration of flow and thinning. While an understanding of these 
ice sheet processes is incomplete, their inclusion in models would 
likely lead to increased sea level projections for the end of the 21st 
century.
---------------------------------------------------------------------------

    \335\ IPCC (2007) Summary for Policymakers. In: Climate Change 
2007: The Physical Science Basis. Contribution of Working Group I to 
the Fourth Assessment Report of the Intergovernmental Panel on 
Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. 
Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge 
University Press, Cambridge, United Kingdom and New York, NY, USA.
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    Sea ice extent is projected to shrink in the Arctic under all IPCC 
emissions scenarios.
(4) Projected Risks and Impacts Associated With Future Climate Change
    Risk to society, ecosystems, and many natural Earth processes 
increases with increases in both the rate and magnitude of climate 
change. Climate warming may increase the possibility of large, abrupt 
regional or global climatic events (e.g., disintegration of the 
Greenland Ice Sheet or collapse of the West Antarctic Ice Sheet). The 
partial deglaciation of Greenland (and possibly West Antarctica) could 
be triggered by a sustained temperature increase of 2 to 7 [deg]F (1 to 
4 [deg]C) above 1990 levels. Such warming would cause a 13 to 20 feet 
(4 to 6 meter) rise in sea level, which would occur over a time period 
of centuries to millennia.
    The CCSP \336\ reports that climate change has the potential to 
accentuate the disparities already evident in the American health care 
system, as many of the expected health effects are likely to fall 
disproportionately on the poor, the elderly, the disabled, and the 
uninsured. The IPCC \337\ states with very high confidence that climate 
change impacts on human health in U.S. cities will be compounded by 
population growth and an aging population.
---------------------------------------------------------------------------

    \336\ Ebi, K.L., J. Balbus, P.L. Kinney, E. Lipp, D. Mills, M.S. 
O'Neill, and M. Wilson (2008) Effects of Global Change on Human 
Health. In: Analyses of the effects of global change on human health 
and welfare and human systems. A Report by the U.S. Climate Change 
Science Program and the Subcommittee on Global Change Research. 
[Gamble, J.L. (ed.), K.L. Ebi, F.G. Sussman, T.J. Wilbanks, 
(Authors)]. U.S. Environmental Protection Agency, Washington, DC, 
USA, pp. 2-1 to 2-78.
    \337\ Field, C.B. et al. (2007) North America. In: Climate 
Change 2007: Impacts, Adaptation and Vulnerability. Contribution of 
Working Group II to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change [M.L. Parry, O.F. 
Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson 
(eds.)]. Cambridge University Press, Cambridge, United Kingdom and 
New York, NY, USA.
---------------------------------------------------------------------------

    Severe heat waves are projected to intensify in magnitude and 
duration over the portions of the United States where these events 
already occur, with potential increases in mortality and morbidity, 
especially among the elderly, young, and frail.
    Some reduction in the risk of death related to extreme cold is 
expected. It is not clear whether reduced mortality from cold will be 
greater or less than increased heat-related mortality in the United 
States due to climate change.
    Increases in regional ozone pollution relative to ozone levels 
without climate change are expected due to higher temperatures and 
weaker circulation in the United States and other world cities relative 
to air quality levels without climate change. Climate change is 
expected to increase regional ozone pollution, with associated risks in 
respiratory illnesses and premature death. In addition to human health 
effects, tropospheric ozone has significant adverse effects on crop 
yields, pasture and forest growth, and species composition. The 
directional effect of climate change on ambient particulate matter 
levels remains uncertain.
    Within settlements experiencing climate change, certain parts of 
the population may be especially vulnerable; these include the poor, 
the elderly, those already in poor health, the disabled, those living 
alone, and/or indigenous populations dependent on one or a few 
resources. Thus, the potential impacts of climate change raise 
environmental justice issues.
    The CCSP \338\ concludes that, with increased CO2 and 
temperature, the life cycle of grain and oilseed crops will likely 
progress more rapidly. But, as temperature rises, these crops will 
increasingly begin to experience failure, especially if climate 
variability increases and precipitation lessens or becomes more 
variable. Furthermore, the marketable yield of many horticultural crops 
(e.g., tomatoes, onions, fruits) is very likely to be more sensitive to 
climate change than grain and oilseed crops.
---------------------------------------------------------------------------

    \338\ Backlund, P., A. Janetos, D.S. Schimel, J. Hatfield, M.G. 
Ryan, S.R. Archer, and D. Lettenmaier (2008) Executive Summary. In: 
The Effects of Climate Change on Agriculture, Land Resources, Water 
Resources, and Biodiversity in the United States. A Report by the 
U.S. Climate Change Science Program and the Subcommittee on Global 
Change Research. Washington, DC., USA, 362 pp.
---------------------------------------------------------------------------

    Higher temperatures will very likely reduce livestock production 
during the summer season in some areas, but these losses will very 
likely be partially offset by warmer temperatures during the winter 
season.
    Cold-water fisheries will likely be negatively affected; warm-water 
fisheries will generally benefit; and the results for cool-water 
fisheries will be mixed, with gains in the northern and losses in the 
southern portions of ranges.
    Climate change has very likely increased the size and number of 
forest fires, insect outbreaks, and tree mortality in the interior 
West, the Southwest, and Alaska, and will continue to do so. Over North 
America, forest growth and productivity have been observed to increase 
since the middle of the 20th century, in part due to observed climate 
change. Rising CO2 will very likely increase photosynthesis 
for forests, but the increased photosynthesis will likely only increase 
wood production in young forests on fertile soils. The combined effects 
of expected increased temperature, CO2, nitrogen deposition, 
ozone, and forest disturbance on soil processes and soil carbon storage 
remain unclear.
    Coastal communities and habitats will be increasingly stressed by 
climate change impacts interacting with development and pollution. Sea 
level is rising along much of the U.S. coast, and the rate of change 
will very likely increase in the future, exacerbating the impacts of 
progressive inundation, storm-surge flooding, and shoreline erosion. 
Storm impacts are likely to be more severe, especially along the Gulf 
and Atlantic coasts. Salt marshes, other coastal habitats, and 
dependent species are threatened by sea level rise, fixed structures 
blocking landward migration, and changes in vegetation. Population 
growth and rising value of infrastructure in coastal areas increases 
vulnerability to climate variability and future climate change.
    Climate change will likely further constrain already over-allocated 
water resources in some regions of the United States, increasing 
competition among agricultural, municipal, industrial, and ecological 
uses. Although water management practices in the United States are 
generally advanced, particularly in the West, the reliance on past 
conditions as the basis for current and future planning may no longer 
be appropriate, as climate change increasingly creates conditions well 
outside of historical observations. Rising temperatures will diminish 
snowpack and increase evaporation, affecting seasonal availability of 
water. In the Great Lakes and major river systems, lower water levels 
are likely to exacerbate challenges relating to water quality, 
navigation, recreation, hydropower generation, water transfers, and 
binational relationships. Decreased water supply and lower water levels 
are likely to exacerbate challenges relating to aquatic navigation in 
the United States.
    Higher water temperatures, increased precipitation intensity, and 
longer periods of low flows will exacerbate many forms of water 
pollution, potentially making attainment of water quality goals more 
difficult. As waters become warmer, the aquatic life they

[[Page 57298]]

now support will be replaced by other species better adapted to warmer 
water. In the long term, warmer water and changing flow may result in 
deterioration of aquatic ecosystems.
    Ocean acidification is projected to continue, resulting in the 
reduced biological production of marine calcifiers, including corals.
    Climate change is likely to affect U.S. energy use and energy 
production and physical and institutional infrastructures. It will also 
likely interact with and possibly exacerbate ongoing environmental 
change and environmental pressures in settlements, particularly in 
Alaska where indigenous communities are facing major environmental and 
cultural impacts. The U.S. energy sector, which relies heavily on water 
for hydropower and cooling capacity, may be adversely impacted by 
changes to water supply and quality in reservoirs and other water 
bodies. Water infrastructure, including drinking water and wastewater 
treatment plants, and sewer and stormwater management systems, will be 
at greater risk of flooding, sea level rise and storm surge, low flows, 
and other factors that could impair performance.
    Disturbances such as wildfires and insect outbreaks are increasing 
in the United States and are likely to intensify in a warmer future 
with warmer winters, drier soils, and longer growing seasons. Although 
recent climate trends have increased vegetation growth, continuing 
increases in disturbances are likely to limit carbon storage, 
facilitate invasive species, and disrupt ecosystem services.
    Over the 21st century, changes in climate will cause species to 
shift north and to higher elevations and fundamentally rearrange U.S. 
ecosystems. Differential capacities for range shifts and constraints 
from development, habitat fragmentation, invasive species, and broken 
ecological connections will alter ecosystem structure, function, and 
services.
(5) Present and Projected U.S. Regional Climate Change Impacts
    Climate change impacts will vary in nature and magnitude across 
different regions of the United States.
    Sustained high summer temperatures, heat waves, and declining air 
quality are projected in the Northeast,\339\ Southeast,\340\ 
Southwest,\341\ and Midwest.\342\ Projected climate change would 
continue to cause loss of sea ice, glacier retreat, permafrost thawing, 
and coastal erosion in Alaska.
---------------------------------------------------------------------------

    \339\ Northeast includes West Virginia, Maryland, Delaware, 
Pennsylvania, New Jersey, New York, Connecticut, Rhode Island, 
Massachusetts, Vermont, New Hampshire, and Maine.
    \340\ Southeast includes Kentucky, Virginia, Arkansas, 
Tennessee, North Carolina, South Carolina, southeast Texas, 
Louisiana, Mississippi, Alabama, Georgia, and Florida.
    \341\ Southwest includes California, Nevada, Utah, western 
Colorado, Arizona, New Mexico (except the extreme eastern section), 
and southwest Texas.
    \342\ The Midwest includes Minnesota, Wisconsin, Michigan, Iowa, 
Illinois, Indiana, Ohio, and Missouri.
---------------------------------------------------------------------------

    Reduced snowpack, earlier spring snowmelt, and increased likelihood 
of seasonal summer droughts are projected in the Northeast, 
Northwest,\343\ and Alaska. More severe, sustained droughts and water 
scarcity are projected in the Southeast, Great Plains,\344\ and 
Southwest.
---------------------------------------------------------------------------

    \343\ The Northwest includes Washington, Idaho, western Montana, 
and Oregon.
    \344\ The Great Plains includes central and eastern Montana, 
North Dakota, South Dakota, Wyoming, Nebraska, eastern Colorado, 
Kansas, extreme eastern New Mexico, central Texas, and Oklahoma.
---------------------------------------------------------------------------

    The Southeast, Midwest, and Northwest in particular are expected to 
be impacted by an increased frequency of heavy downpours and greater 
flood risk.
    Ecosystems of the Southeast, Midwest, Great Plains, Southwest, 
Northwest, and Alaska are expected to experience altered distribution 
of native species (including local extinctions), more frequent and 
intense wildfires, and an increase in insect pest outbreaks and 
invasive species.
    Sea level rise is expected to increase storm surge height and 
strength, flooding, erosion, and wetland loss along the coasts, 
particularly in the Northeast, Southeast, and islands.
    Warmer water temperatures and ocean acidification are expected to 
degrade important aquatic resources of islands and coasts such as coral 
reefs and fisheries.
    A longer growing season, low levels of warming, and fertilization 
effects of carbon dioxide may benefit certain crop species and forests, 
particularly in the Northeast and Alaska. Projected summer rainfall 
increases in the Pacific islands may augment limited freshwater 
supplies. Cold-related mortality is projected to decrease, especially 
in the Southeast. In the Midwest in particular, heating oil demand and 
snow-related traffic accidents are expected to decrease.
    Climate change impacts in certain regions of the world may 
exacerbate problems that raise humanitarian, trade, and national 
security issues for the United States. The IPCC \345\ identifies the 
most vulnerable world regions as the Arctic, because of the effects of 
high rates of projected warming on natural systems; Africa, especially 
the sub-Saharan region, because of current low adaptive capacity as 
well as climate change; small islands, due to high exposure of 
population and infrastructure to risk of sea level rise and increased 
storm surge; and Asian mega-deltas, such as the Ganges-Brahmaputra and 
the Zhujiang, due to large populations and high exposure to sea level 
rise, storm surge and river flooding. Climate change has been described 
as a potential threat multiplier with regard to national security 
issues.
---------------------------------------------------------------------------

    \345\ Parry, M.L. et al. (2007) Technical Summary. In: Climate 
Change 2007: Impacts, Adaptation and Vulnerability. Contribution of 
Working Group II to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change [M.L. Parry, O.F. 
Canziani, J.P. Palutikof, P.J. van der Linden, and C.E. Hanson 
(eds.)], Cambridge University Press, Cambridge, United Kingdom, pp. 
23S78.
---------------------------------------------------------------------------

E. Changes in Atmospheric CO2 Concentrations, Global Mean 
Temperature, Sea Level Rise, and Ocean pH Associated With the Program's 
GHG Emissions Reductions

    EPA examined \346\ the reductions in CO2 and other GHGs 
associated with this rulemaking and analyzed the projected effects on 
atmospheric CO2 concentrations, global mean surface 
temperature, sea level rise, and ocean pH which are common variables 
used as indicators of climate change. The analysis projects that the 
preferred alternative of this program will reduce atmospheric 
concentrations of CO2, global climate warming and sea level 
rise relative to the reference case. Although the projected reductions 
and improvements are small in comparison to the total projected climate 
change, they are quantifiable, directionally consistent, and will 
contribute to reducing the risks associated with climate change. 
Climate change is a global phenomenon and EPA recognizes that this one 
national action alone will not prevent it: EPA notes this would be true 
for any given GHG mitigation action when taken alone. EPA also notes 
that a substantial portion of CO2 emitted into the 
atmosphere is not removed by natural processes for millennia, and 
therefore each unit of CO2 not emitted into the atmosphere 
due to this program

[[Page 57299]]

avoids essentially permanent climate change on centennial time scales. 
The heavy-duty program makes a significant contribution towards 
addressing the challenge by producing substantial reductions in 
greenhouse gas emissions from a particularly large and important source 
of emissions. As the Supreme Court recognized in State of Massachusetts 
v. EPA, [A]agencies, like legislatures, do not generally resolve 
massive problems like climate change in one fell regulatory swoop. 549 
U.S. 497, 524 (2008). They instead whittle away at them over time. Id.
---------------------------------------------------------------------------

    \346\ Using the Model for the Assessment of Greenhouse Gas 
Induced Climate Change (MAGICC) 5.3v2, http://www.cgd.ucar.edu/cas/wigley/magicc/), EPA estimated the effects of this rulemaking's 
greenhouse gas emissions reductions on global mean temperature and 
sea level. Please refer to Chapter 8.4 of the RIA for additional 
information.
---------------------------------------------------------------------------

    EPA determines that the projected reductions in atmospheric 
CO2, global mean temperature and sea level rise are 
meaningful in the context of this final action. In addition, EPA has 
conducted an analysis to evaluate the projected changes in ocean pH in 
the context of the changes in emissions from this rulemaking. The 
results of the analysis demonstrate that relative to the reference 
case, projected atmospheric CO2 concentrations are estimated 
to be reduced by 0.691 to 0.787 part per million by volume (ppmv), 
global mean temperature is estimated to be reduced by 0.0017 to 
0.0042[deg]C, and sea-level rise is projected to be reduced by 
approximately 0.017-0.040 cm by 2100, based on a range of climate 
sensitivities. The analysis also demonstrates that ocean pH will 
increase by 0.0003 pH units by 2100 relative to the reference case.
(1) Estimated Projected Reductions in Atmospheric CO2 
Concentration, Global Mean Surface Temperatures, Sea Level Rise, and 
Ocean pH
    EPA estimated changes in the atmospheric CO2 
concentration, global mean temperature, and sea level rise out to 2100 
resulting from the emissions reductions in this rulemaking using the 
GCAM (Global Change Assessment Model, formerly MiniCAM), integrated 
assessment model \347\ coupled with the Model for the Assessment of 
Greenhouse Gas Induced Climate Change (MAGICC, version 5.3v2).\348\ 
GCAM was used to create the globally and temporally consistent set of 
climate relevant variables required for running MAGICC. MAGICC was then 
used to estimate the projected change in these variables over time. 
Given the magnitude of the estimated emissions reductions associated 
with this action, a simple climate model such as MAGICC is reasonable 
for estimating the atmospheric and climate response. This widely-used, 
peer reviewed modeling tool was also used to project temperature and 
sea level rise under different emissions scenarios in the Third and 
Fourth Assessments of the IPCC.
---------------------------------------------------------------------------

    \347\ GCAM is a long-term, global integrated assessment model of 
energy, economy, agriculture and land use, that considers the 
sources of emissions of a suite of GHG's, emitted in 14 globally 
disaggregated regions, the fate of emissions to the atmosphere, and 
the consequences of changing concentrations of greenhouse related 
gases for climate change. GCAM begins with a representation of 
demographic and economic developments in each region and combines 
these with assumptions about technology development to describe an 
internally consistent representation of energy, agriculture, land-
use, and economic developments that in turn shape global emissions.
    Brenkert A, S. Smith, S. Kim, and H. Pitcher, 2003: Model 
Documentation for the MiniCAM. PNNL-14337, Pacific Northwest 
National Laboratory, Richland, Washington.
    \348\ Wigley, T.M.L. 2008. MAGICC 5.3.v2 User Manual. UCAR--
Climate and Global Dynamics Division, Boulder, Colorado. http://www.cgd.ucar.edu/cas/wigley/magicc/.
---------------------------------------------------------------------------

    The integrated impact of the following pollutant and greenhouse gas 
emissions changes are considered: CO2, CH4, 
N2O, HFC-134a, NOX, CO2 and 
SO2, and volatile organic compounds (VOC). For 
CO2, CH4, HFC-134a, and N2O an annual 
time-series of (upstream + downstream) emissions reductions estimated 
from the rulemaking were input directly. The GHG emissions reductions, 
from Section VI.C, were applied as net reductions to a global reference 
case (or baseline) emissions scenario in GCAM to generate an emissions 
scenario specific to this rulemaking. For CO, VOCs, SO2, and 
NOX, emissions reductions were estimated for 2018, 2030, and 
2050 (provided in Section VII.A). EPA then linearly scaled emissions 
reductions for these gases between a zero input value in 2013 and the 
value supplied for 2018 to produce the reductions for 2014-2018. A 
similar scaling was used for 2019-2029 and 2031-2050. The emissions 
reductions past 2050 for all gases were scaled with total U.S. road 
transportation fuel consumption from the GCAM reference scenario. Road 
transport fuel consumption past 2050 does not change significantly and 
thus emissions reductions remain relatively constant from 2050 through 
2100. Specific details about the GCAM reference case scenario can be 
found in Chapter 8.4 of the RIA that accompanies this preamble.
    MAGICC calculates the forcing response at the global scale from 
changes in atmospheric concentrations of CO2, 
CH4, N2O, HFCs, and tropospheric ozone. It also 
includes the effects of temperature changes on stratospheric ozone and 
the effects of CH4 emissions on stratospheric water vapor. 
Changes in CH4, NOX, VOC, and CO emissions affect 
both O3 concentrations and CH4 concentrations. 
MAGICC includes the relative climate forcing effects of changes in 
sulfate concentrations due to changing SO2 emissions, 
including both the direct effect of sulfate particles and the indirect 
effects related to cloud interactions. However, MAGICC does not 
calculate the effect of changes in concentrations of other aerosols 
such as nitrates, black carbon, or organic carbon, making the 
assumption that the sulfate cooling effect is a proxy for the sum of 
all the aerosol effects. Therefore, the climate effects of changes in 
PM2.5 emissions and precursors (besides SO2) 
which are presented in the RIA Chapter 5 were not included in the 
calculations in this section. MAGICC also calculates all climate 
effects at the global scale. This global scale captures the climate 
effects of the long-lived, well-mixed greenhouse gases, but does not 
address the fact that short-lived climate forcers such as aerosols and 
ozone can have effects that vary with location and timing of emissions. 
Black carbon in particular is known to cause a positive forcing or 
warming effect by absorbing incoming solar radiation, but there are 
uncertainties about the magnitude of that warming effect and the 
interaction of black carbon (and other co-emitted aerosol species) with 
clouds. While black carbon is likely to be an important contributor to 
climate change, it would be premature to include quantification of 
black carbon climate impacts in an analysis of the final standards at 
this time.
    Changes in atmospheric CO2 concentration, global mean 
temperature, and sea level rise for both the reference case and the 
emissions scenarios associated with this action were computed using 
MAGICC. To calculate the reductions in the atmospheric CO2 
concentrations as well as in temperature and sea level resulting from 
this action, the output from the policy scenario associated with the 
preferred approach of this action was subtracted from an existing 
Global Change Assessment Model (GCAM, formerly MiniCAM) reference 
emission scenario. To capture some key uncertainties in the climate 
system with the MAGICC model, changes in atmospheric CO2, 
global mean temperature and sea level rise were projected across the 
most current IPCC range of climate sensitivities, from 1.5 [deg]C to 
6.0 [deg]C.\349\ This range reflects

[[Page 57300]]

the uncertainty for equilibrium climate sensitivity for how much global 
mean temperature would rise if the concentration of carbon dioxide in 
the atmosphere were to double. The information for this range come from 
constraints from past climate change on various time scales, and the 
spread of results for climate sensitivity from ensembles of 
models.\350\ Details about this modeling analysis can be found in the 
RIA Chapter 8.4.
---------------------------------------------------------------------------

    \349\ In IPCC reports, equilibrium climate sensitivity refers to 
the equilibrium change in the annual mean global surface temperature 
following a doubling of the atmospheric equivalent carbon dioxide 
concentration. The IPCC states that climate sensitivity is 
``likely'' to be in the range of 2 [deg]C to 4.5 [deg]C, ``very 
unlikely'' to be less than 1.5 [deg]C, and ``values substantially 
higher than 4.5 [deg]C cannot be excluded.'' IPCC WGI, 2007, Climate 
Change 2007--The Physical Science Basis, Contribution of Working 
Group I to the Fourth Assessment Report of the IPCC, http://www.ipcc.ch/.
    \350\ Meehl, G.A. et al. (2007) Global Climate Projections. In: 
Climate Change 2007: The Physical Science Basis. Contribution of 
Working Group I to the Fourth Assessment Report of the 
Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. 
Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller 
(eds.)]. Cambridge University Press, Cambridge, United Kingdom and 
New York, NY, USA.
---------------------------------------------------------------------------

    The results of this modeling, summarized in Table VI-8, show small, 
but quantifiable, reductions in atmospheric CO2 
concentrations, projected global mean temperature and sea level 
resulting from this action, across all climate sensitivities. As a 
result of the emission reductions from the final standards for this 
action, relative to the reference case the atmospheric CO2 
concentration is projected to be reduced by 0.691-0.787 ppmv, the 
global mean temperature is projected to be reduced by approximately 
0.0017-0.0042 [deg]C by 2100, and global mean sea level rise is 
projected to be reduced by approximately 0.017-0.040 cm by 2100. The 
range of reductions in global mean temperature and sea level rise is 
larger than that for CO2 concentrations because 
CO2 concentrations are only weakly coupled to climate 
sensitivity through the dependence on temperature of the rate of ocean 
absorption of CO2, whereas the magnitude of temperature 
change response to CO2 changes (and therefore sea level 
rise) is more tightly coupled to climate sensitivity in the MAGICC 
model.

 Table VI-8--Impact of GHG Emissions Reductions on Projected Changes in Global Climate Associated With the Final
                    Rulemaking (Based on a Range of Climate Sensitivities From 1.5-6 [deg]C)
----------------------------------------------------------------------------------------------------------------
                Variable                       Units           Year                  Projected change
----------------------------------------------------------------------------------------------------------------
Atmospheric CO2 Concentration...........            ppmv            2100  -0.691 to -0.787.
Global Mean Surface Temperature.........          [deg]C            2100  -0.0017 to -0.0042.
Sea Level Rise..........................              cm            2100  -0.017 to -0.040.
Ocean pH................................        pH units            2100  0.0003 \a\.
----------------------------------------------------------------------------------------------------------------
Note:
\a\ The value for projected change in ocean pH is based on a climate sensitivity of 3.0.

    The projected reductions are small relative to the change in 
temperature (1.8-4.8 [deg]C), sea level rise (27--51 cm), and ocean 
acidity (-0.30 pH units) from 1990 to 2100 from the MAGICC simulations 
for the GCAM reference case. However, this is to be expected given the 
magnitude of emissions reductions expected from the program in the 
context of global emissions. This uncertainty range does not include 
the effects of uncertainty in future emissions. It should also be noted 
that the calculations in MAGICC do not include the possible effects of 
accelerated ice flow in Greenland and/or Antarctica: the recent NRC 
report estimated a likely sea level increase for the A1B SRES scenario 
of 0.5 to 1.0 meters.\351\ Further discussion of EPA's modeling 
analysis is found in the RIA, Chapter 8.
---------------------------------------------------------------------------

    \351\ National Research Council, 2011. Climate Stabilization 
Targets: Emissions, Concentrations, and Impacts over Decades to 
Millenia. Washington, DC: National Academies Press.
---------------------------------------------------------------------------

    EPA used the Program CO2SYS,\352\ version 1.05 to estimate 
projected changes in ocean pH for tropical waters based on the 
atmospheric CO2 concentration change (reduction) resulting 
from this action. The program performs calculations relating parameters 
of the CO2 system in seawater. EPA used the program to 
calculate ocean pH as a function of atmospheric CO2 
concentrations, among other specified input conditions. Based on the 
projected atmospheric CO2 concentration reductions resulting 
from this action, the program calculates an increase in ocean pH of 
0.0003 pH units in 2100 relative to the reference case (compared to a 
decrease of 0.3 pH units from 1990 to 2100 in the reference case). 
Thus, this analysis indicates the projected decrease in atmospheric 
CO2 concentrations from the program will result in an 
increase in ocean pH. For additional validation, results were generated 
using different known constants from the literature. A comprehensive 
discussion of the modeling analysis associated with ocean pH is 
provided in the RIA, Chapter 8.
---------------------------------------------------------------------------

    \352\ Lewis, E., and D. W. R. Wallace. 1998. Program Developed 
for CO2 System Calculations. ORNL/CDIAC-105. Carbon 
Dioxide Information Analysis Center, Oak Ridge National Laboratory, 
U.S. Department of Energy, Oak Ridge, Tennessee.
---------------------------------------------------------------------------

(2) Program's Effect on Climate
    As a substantial portion of CO2 emitted into the 
atmosphere is not removed by natural processes for millennia, each unit 
of CO2 not emitted into the atmosphere avoids essentially 
permanent climate change on centennial time scales. Reductions in 
emissions in the near-term are important in determining long-term 
climate stabilization and associated impacts experienced not just over 
the next decades but in the coming centuries and millennia.\353\ Though 
the magnitude of the avoided climate change projected here is small in 
comparison to the total projected changes, these reductions represent a 
reduction in the adverse risks associated with climate change (though 
these risks were not formally estimated for this action) across a range 
of equilibrium climate sensitivities.
---------------------------------------------------------------------------

    \353\ See NRC 2011, Note 351.
---------------------------------------------------------------------------

    EPA's analysis of the program's impact on global climate conditions 
is intended to quantify these potential reductions using the best 
available science. EPA's modeling results show repeatable, consistent 
reductions relative to the reference case in changes of CO2 
concentration, temperature, sea-level rise, and ocean pH over the next 
century.

VII. How will this final action impact non-GHG emissions and their 
associated effects?

A. Emissions Inventory Impacts

(1) Upstream Impacts of the Program
    Increasing efficiency in heavy-duty vehicles will result in reduced 
fuel demand and therefore reductions in the emissions associated with 
all processes involved in getting petroleum to the pump. These 
projected upstream emission impacts on criteria pollutants

[[Page 57301]]

are summarized in Table VII-1. Table VII-2 shows the corresponding 
projected impacts on upstream air toxic emissions in 2030.

 Table VII-1--Overall Estimated Upstream Impacts on Criteria Pollutants for Calendar Years 2018, 2030, and 2050
                                                  [Short tons]
----------------------------------------------------------------------------------------------------------------
              Calendar year                      NOX               VOC               CO               PM2.5
----------------------------------------------------------------------------------------------------------------
2018....................................            -6,475            -1,765            -2,217              -971
2030....................................            -9,975            -4,367            -3,331            -1,379
2050....................................           -14,243            -6,379            -4,785            -1,998
----------------------------------------------------------------------------------------------------------------

                          Table VII-2--Overall Estimated Upstream Impacts on AIR TOXICS for Calendar Years 2018, 2030, and 2050
                                                                      [Short tons]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         Calendar year                               Benzene        1,3-butadiene     Formaldehyde      Acetaldehyde        Acrolein
--------------------------------------------------------------------------------------------------------------------------------------------------------
2018..........................................................               -12              -0.6               -12                -1              -0.2
2030..........................................................               -19              -0.9               -26                -3              -0.5
2050..........................................................               -28              -1.2               -35                -5              -0.6
--------------------------------------------------------------------------------------------------------------------------------------------------------

    To project these impacts, EPA estimated the impact of reduced 
petroleum volumes on the extraction and transportation of crude oil as 
well as the production and distribution of finished gasoline and 
diesel. For the purpose of assessing domestic-only emission reductions 
it was necessary to estimate the fraction of fuel savings attributable 
to domestic finished gasoline and diesel, and of this fuel what 
fraction is produced from domestic crude. For this analysis EPA 
estimated that 50 percent of fuel savings is attributable to domestic 
finished gasoline and diesel and that 90 percent of this gasoline and 
diesel originated from imported crude. Emission factors for most 
upstream emission sources are based on the GREET1.8 model, developed by 
DOE's Argonne National Laboratory but in some cases the GREET values 
were modified or updated by EPA to be consistent with the National 
Emission Inventory. These updates are consistent with those used for 
the upstream analysis included in the Light-Duty GHG rulemaking. More 
information on the development of the emission factors used in this 
analysis can be found in RIA chapter 5.
(2) Downstream Impacts of the Program
    While these final rules do not regulate non-GHG pollutants, EPA 
expects reductions in downstream emissions of most non-GHG pollutants. 
These pollutants include NOX, SO2, VOC, CO, and 
PM. The primary reasons for this are the improvements in road load 
(aerodynamics and tire rolling resistance) under the program and the 
agency's anticipation of increased use of APUs in combination tractors 
for GHG reduction purposes during extended idling. APUs exhibit 
different non-GHG emissions characteristics compared to the on-road 
engines they would replace during extended idling. Another reason is 
that emissions from certain pollutants (e.g., SO2) are 
proportional to fuel consumption. For vehicle types not affected by 
road load improvements, non-GHG emissions may increase very slightly 
due to VMT rebound. EPA used MOVES to determine non-GHG emissions 
inventories for baseline and control cases. Further information about 
the MOVES analysis is available in Section VI and RIA chapter 5. The 
improvements in road load, use of APUs, and VMT rebound were included 
in the MOVES runs and post-processing. Table VII-3 summarizes the 
downstream criteria pollutant impacts of this program. Most of the 
impacts shown are through projected increased APU use. Because APUs are 
required to meet much less stringent PM standards than on-road engines, 
the projected widespread use of APUs leads to higher PM2.5. 
Table VII-4 summarizes the downstream air toxics impacts of this 
program.

                                        Table VII-3--Overall Estimated Downstream Impacts on Criteria Pollutants
                                                                      [Short tons]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Downstream PM2.5
                         Calendar year                           Downstream NOX    Downstream VOC    Downstream SO2     Downstream CO           a
--------------------------------------------------------------------------------------------------------------------------------------------------------
2018..........................................................          -107,135           -12,951              -145           -25,614               803
2030..........................................................          -235,046           -25,502              -423           -52,212             1,751
2050..........................................................          -326,413           -35,126              -614           -72,049             2,441
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
a Positive number means emissions would increase from baseline to control case. PM2.5 from tire wear and brake wear is included.

                                             Table VII-4--Overall Estimated Downstream Impacts on Air Toxics
                                                                      [Short tons]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         Calendar year                               Benzene        1,3-butadiene     Formaldehyde      Acetaldehyde        Acrolein
--------------------------------------------------------------------------------------------------------------------------------------------------------
2018..........................................................              -158              -0.3            -2,853              -871              -120
2030..........................................................              -341               0.4            -6,255            -1,908              -263

[[Page 57302]]

 
2050..........................................................              -472               0.8            -8,689            -2,650              -365
--------------------------------------------------------------------------------------------------------------------------------------------------------

(3) Total Impacts of the Program
    As shown in Table VII-5 and Table VII-6, the agencies estimate that 
this program would result in reductions of NOX, VOC, CO, PM, 
and air toxics. For NOX, VOC, and CO, much of the net 
reductions are realized through the use of APUs, which emit these 
pollutants at a lower rate than on-road engines during extended idle 
operation. Additional reductions are achieved in all pollutants through 
reduced road load (improved aerodynamics and tire rolling resistance), 
which reduces the amount of work required to travel a given distance. 
For SOX, downstream emissions are roughly proportional to 
fuel consumption; therefore a decrease is seen in both upstream and 
downstream sources. The downstream increase in PM2.5 due to 
APU use is mostly negated by upstream PM2.5 reductions, 
though our calculations show a slight net increase in 2030 and 
2050.\354\
---------------------------------------------------------------------------

    \354\ Although the net impact is small when aggregated to the 
national level, it is unlikely that the geographic location of 
increases in downstream PM2.5 emissions will coincide 
with the location of decreases in upstream PM2.5 
emissions. Impacts of the emissions changes are included in the air 
quality modeling, discussed in Section VII.D of this preamble and in 
Chapter 8 of the RIA.

                             Table VII-5--Overall Estimated Total Impacts (Upstream Plus Downstream) on Criteria Pollutants
                                [Results are shown in both short tons and percent change from baseline to control case.]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  NOX                      VOC                   SO2                   CO                   PM2.5
                                      ------------------------------------------------------------------------------------------------------------------
                  CY                                                short                 short                 short                 short
                                         short tons        %         tons        %         tons        %         tons        %         tons        %
--------------------------------------------------------------------------------------------------------------------------------------------------------
2018.................................        -113,610       -6.2    -14,715       -5.6     -4,566       -4.5    -27,832       -1.0       -167       -0.2
2030.................................        -245,129      -21.0    -29,932      -16.0     -6,888      -10.1    -55,579       -2.1        356       10.1
2050.................................        -340,656      -23.7    -41,506      -18.3     -9,857      -11.0    -76,834       -2.2        443       10.1
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                  Table VII-6--Overall Estimated Total Impacts on Air Toxics (Upstream Plus Downstream)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Benzene            1,3-butadiene         Formaldehyde          Acetaldehyde            Acrolein
                                           -------------------------------------------------------------------------------------------------------------
                    CY                        short                 short                 short                 short                 short
                                               tons        %         tons        %         tons        %         tons        %         tons        %
--------------------------------------------------------------------------------------------------------------------------------------------------------
2018......................................       -170       -4.8       -0.9       -0.1     -2,865      -18.3       -873      -13.9     -120.0      -12.4
2030......................................       -359      -15.0       -0.5       -0.1     -6,282      -46.2     -1,912      -40.2     -263.0      -40.0
2050......................................       -500      -17.4       -0.4       -0.1     -8,725      -49.5     -2,655      -44.2     -365.4      -44.5
--------------------------------------------------------------------------------------------------------------------------------------------------------

B. Health Effects of Non-GHG Pollutants

    In this section we discuss health effects associated with exposure 
to some of the criteria and air toxic pollutants impacted by the final 
heavy-duty vehicle standards.
(1) Particulate Matter
(a) Background
    Particulate matter is a generic term for a broad class of 
chemically and physically diverse substances. It can be principally 
characterized as discrete particles that exist in the condensed (liquid 
or solid) phase spanning several orders of magnitude in size. Since 
1987, EPA has delineated that subset of inhalable particles small 
enough to penetrate to the thoracic region (including the 
tracheobronchial and alveolar regions) of the respiratory tract 
(referred to as thoracic particles). Current National Ambient Air 
Quality Standards (NAAQS) use PM2.5 as the indicator for 
fine particles (with PM2.5 referring to particles with a 
nominal mean aerodynamic diameter less than or equal to 2.5 [mu]m), and 
use PM10 as the indicator for purposes of regulating the 
coarse fraction of PM10 (referred to as thoracic coarse 
particles or coarse-fraction particles; generally including particles 
with a nominal mean aerodynamic diameter greater than 2.5 [mu]m and 
less than or equal to 10 [mu]m, or PM10-2.5). Ultrafine 
particles are a subset of fine particles, generally less than 100 
nanometers (0.1 [mu]m) in aerodynamic diameter.
    Fine particles are produced primarily by combustion processes and 
by transformations of gaseous emissions (e.g., SOX, 
NOX, and VOC) in the atmosphere. The chemical and physical 
properties of PM2.5 may vary greatly with time, region, 
meteorology, and source category. Thus, PM2.5 may include a 
complex mixture of different pollutants including sulfates, nitrates, 
organic compounds, elemental carbon and metal compounds. These 
particles can remain in the atmosphere for days to weeks and travel 
hundreds to thousands of kilometers.
(b) Health Effects of PM
    Scientific studies show ambient PM is associated with a series of 
adverse health effects. These health effects are discussed in detail in 
EPA's Integrated Science Assessment for Particulate Matter (ISA).\355\ 
Further discussion of health effects associated with PM can also be 
found in the RIA for this final action. The ISA summarizes evidence 
associated with PM2.5, PM10-2.5, and ultrafine 
particles.
---------------------------------------------------------------------------

    \355\ U.S. EPA (2009) Integrated Science Assessment for 
Particulate Matter (Final Report). U.S. Environmental Protection 
Agency, Washington, DC, EPA/600/R-08/139F, Docket EPA-HQ-OAR-2010-
0162.
---------------------------------------------------------------------------

    The ISA concludes that health effects associated with short-term 
exposures (hours to days) to ambient PM2.5 include 
mortality, cardiovascular effects, such as

[[Page 57303]]

altered vasomotor function and hospital admissions and emergency 
department visits for ischemic heart disease and congestive heart 
failure, and respiratory effects, such as exacerbation of asthma 
symptoms in children and hospital admissions and emergency department 
visits for chronic obstructive pulmonary disease and respiratory 
infections.\356\ The ISA notes that long-term exposure to 
PM2.5 (months to years) is associated with the development/
progression of cardiovascular disease, premature mortality, and 
respiratory effects, including reduced lung function growth, increased 
respiratory symptoms, and asthma development.\357\ The ISA concludes 
that the currently available scientific evidence from epidemiologic, 
controlled human exposure, and toxicological studies supports a causal 
association between short- and long-term exposures to PM2.5 
and cardiovascular effects and mortality. Furthermore, the ISA 
concludes that the collective evidence supports likely causal 
associations between short- and long-term PM2.5 exposures 
and respiratory effects. The ISA also concludes that the scientific 
evidence is suggestive of a causal association for reproductive and 
developmental effects and cancer, mutagenicity, and genotoxicity and 
long-term exposure to PM2.5.\358\
---------------------------------------------------------------------------

    \356\ See U.S. EPA, 2009 Final PM ISA, Note 355, at Section 
2.3.1.1.
    \357\ See U.S. EPA 2009 Final PM ISA, Note 355, at page 2-12, 
Sections 7.3.1.1 and 7.3.2.1.
    \358\ See U.S. EPA 2009 Final PM ISA, Note 355, at Section 
2.3.2.
---------------------------------------------------------------------------

    For PM10-2.5, the ISA concludes that the current 
evidence is suggestive of a causal relationship between short-term 
exposures and cardiovascular effects, such as hospitalization for 
ischemic heart disease. There is also suggestive evidence of a causal 
relationship between short-term PM10-2.5 exposure and 
mortality and respiratory effects. Data are inadequate to draw 
conclusions regarding the health effects associated with long-term 
exposure to PM10-2.5.\359\
---------------------------------------------------------------------------

    \359\ See U.S. EPA 2009 Final PM ISA, Note 355, at Section 
2.3.4, Table 2-6.
---------------------------------------------------------------------------

    For ultrafine particles, the ISA concludes that there is suggestive 
evidence of a causal relationship between short-term exposures and 
cardiovascular effects, such as changes in heart rhythm and blood 
vessel function. It also concludes that there is suggestive evidence of 
association between short-term exposure to ultrafine particles and 
respiratory effects. Data are inadequate to draw conclusions regarding 
the health effects associated with long-term exposure to ultrafine 
particles.\360\
---------------------------------------------------------------------------

    \360\ See U.S. EPA 2009 Final PM ISA, Note 355, at Section 
2.3.5, Table 2-6.
---------------------------------------------------------------------------

(2) Ozone
(a) Background
    Ground-level ozone pollution is typically formed by the reaction of 
VOC and NOX in the lower atmosphere in the presence of 
sunlight. These pollutants, often referred to as ozone precursors, are 
emitted by many types of pollution sources, such as highway and nonroad 
motor vehicles and engines, power plants, chemical plants, refineries, 
makers of consumer and commercial products, industrial facilities, and 
smaller area sources.
    The science of ozone formation, transport, and accumulation is 
complex. Ground-level ozone is produced and destroyed in a cyclical set 
of chemical reactions, many of which are sensitive to temperature and 
sunlight. When ambient temperatures and sunlight levels remain high for 
several days and the air is relatively stagnant, ozone and its 
precursors can build up and result in more ozone than typically occurs 
on a single high-temperature day. Ozone can be transported hundreds of 
miles downwind from precursor emissions, resulting in elevated ozone 
levels even in areas with low local VOC or NOX emissions.
(b) Health Effects of Ozone
    The health and welfare effects of ozone are well documented and are 
assessed in EPA's 2006 Air Quality Criteria Document and 2007 Staff 
Paper.361 362 People who are more susceptible to effects 
associated with exposure to ozone can include children, the elderly, 
and individuals with respiratory disease such as asthma. Those with 
greater exposures to ozone, for instance due to time spent outdoors 
(e.g., children and outdoor workers), are of particular concern. Ozone 
can irritate the respiratory system, causing coughing, throat 
irritation, and breathing discomfort. Ozone can reduce lung function 
and cause pulmonary inflammation in healthy individuals. Ozone can also 
aggravate asthma, leading to more asthma attacks that require medical 
attention and/or the use of additional medication. Thus, ambient ozone 
may cause both healthy and asthmatic individuals to limit their outdoor 
activities. In addition, there is suggestive evidence of a contribution 
of ozone to cardiovascular-related morbidity and highly suggestive 
evidence that short-term ozone exposure directly or indirectly 
contributes to non-accidental and cardiopulmonary-related mortality, 
but additional research is needed to clarify the underlying mechanisms 
causing these effects. In a recent report on the estimation of ozone-
related premature mortality published by NRC, a panel of experts and 
reviewers concluded that short-term exposure to ambient ozone is likely 
to contribute to premature deaths and that ozone-related mortality 
should be included in estimates of the health benefits of reducing 
ozone exposure.\363\ Animal toxicological evidence indicates that with 
repeated exposure, ozone can inflame and damage the lining of the 
lungs, which may lead to permanent changes in lung tissue and 
irreversible reductions in lung function. The respiratory effects 
observed in controlled human exposure studies and animal studies are 
coherent with the evidence from epidemiologic studies supporting a 
causal relationship between acute ambient ozone exposures and increased 
respiratory-related emergency room visits and hospitalizations in the 
warm season. In addition, there is suggestive evidence of a 
contribution of ozone to cardiovascular-related morbidity and non-
accidental and cardiopulmonary mortality.
---------------------------------------------------------------------------

    \361\ U.S. EPA. (2006). Air Quality Criteria for Ozone and 
Related Photochemical Oxidants (Final). EPA/600/R-05/004aF-cF. 
Washington, DC: U.S. EPA. Docket EPA-HQ-OAR-2010-0162.
    \362\ U.S. EPA. (2007). Review of the National Ambient Air 
Quality Standards for Ozone: Policy Assessment of Scientific and 
Technical Information, OAQPS Staff Paper. EPA-452/R-07-003. 
Washington, DC, U.S. EPA. Docket EPA-HQ-OAR-2010-0162.
    \363\ National Research Council (NRC), 2008. Estimating 
Mortality Risk Reduction and Economic Benefits from Controlling 
Ozone Air Pollution. The National Academies Press: Washington, DC 
Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

(3) Nitrogen Oxides and Sulfur Oxides
(a) Background
    Nitrogen dioxide (NO2) is a member of the NOX 
family of gases. Most NO2 is formed in the air through the 
oxidation of nitric oxide (NO) emitted when fuel is burned at a high 
temperature. SO2, a member of the sulfur oxide 
(SOX) family of gases, is formed from burning fuels 
containing sulfur (e.g., coal or oil derived), extracting gasoline from 
oil, or extracting metals from ore.
    SO2 and NO2 can dissolve in water droplets 
and further oxidize to form sulfuric and nitric acid which react with 
ammonia to form sulfates and nitrates, both of which are important 
components of ambient PM. The health effects of ambient PM are 
discussed in Section 0 of this preamble. NOX and NMHC are 
the two major precursors of

[[Page 57304]]

ozone. The health effects of ozone are covered in Section 0.
(b) Health Effects of NO2
    Information on the health effects of NO2 can be found in 
the EPA Integrated Science Assessment (ISA) for Nitrogen Oxides.\364\ 
The EPA has concluded that the findings of epidemiologic, controlled 
human exposure, and animal toxicological studies provide evidence that 
is sufficient to infer a likely causal relationship between respiratory 
effects and short-term NO2 exposure. The ISA concludes that 
the strongest evidence for such a relationship comes from epidemiologic 
studies of respiratory effects including symptoms, emergency department 
visits, and hospital admissions. The ISA also draws two broad 
conclusions regarding airway responsiveness following NO2 
exposure. First, the ISA concludes that NO2 exposure may 
enhance the sensitivity to allergen-induced decrements in lung function 
and increase the allergen-induced airway inflammatory response 
following 30-minute exposures of asthmatics to NO2 
concentrations as low as 0.26 ppm. In addition, small but significant 
increases in non-specific airway hyperresponsiveness were reported 
following 1-hour exposures of asthmatics to 0.1 ppm NO2. 
Second, exposure to NO2 has been found to enhance the 
inherent responsiveness of the airway to subsequent nonspecific 
challenges in controlled human exposure studies of asthmatic subjects. 
Enhanced airway responsiveness could have important clinical 
implications for asthmatics since transient increases in airway 
responsiveness following NO2 exposure have the potential to 
increase symptoms and worsen asthma control. Together, the 
epidemiologic and experimental data sets form a plausible, consistent, 
and coherent description of a relationship between NO2 
exposures and an array of adverse health effects that range from the 
onset of respiratory symptoms to hospital admission.
---------------------------------------------------------------------------

    \364\ U.S. EPA (2008). Integrated Science Assessment for Oxides 
of Nitrogen--Health Criteria (Final Report). EPA/600/R-08/071. 
Washington, DC: U.S.EPA. Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    Although the weight of evidence supporting a causal relationship is 
somewhat less certain than that associated with respiratory morbidity, 
NO2 has also been linked to other health endpoints. These 
include all-cause (nonaccidental) mortality, hospital admissions or 
emergency department visits for cardiovascular disease, and decrements 
in lung function growth associated with chronic exposure.
(c) Health Effects of SO2
    Information on the health effects of SO2 can be found in 
the EPA Integrated Science Assessment for Sulfur Oxides.\365\ 
SO2 has long been known to cause adverse respiratory health 
effects, particularly among individuals with asthma. Other potentially 
sensitive groups include children and the elderly. During periods of 
elevated ventilation, asthmatics may experience symptomatic 
bronchoconstriction within minutes of exposure. Following an extensive 
evaluation of health evidence from epidemiologic and laboratory 
studies, the EPA has concluded that there is a causal relationship 
between respiratory health effects and short-term exposure to 
SO2. Separately, based on an evaluation of the epidemiologic 
evidence of associations between short-term exposure to SO2 
and mortality, the EPA has concluded that the overall evidence is 
suggestive of a causal relationship between short-term exposure to 
SO2 and mortality.
---------------------------------------------------------------------------

    \365\ U.S. EPA. (2008). Integrated Science Assessment (ISA) for 
Sulfur Oxides--Health Criteria (Final Report). EPA/600/R-08/047F. 
Washington, DC: U.S. Environmental Protection Agency. Docket EPA-HQ-
OAR-2010-0162.
---------------------------------------------------------------------------

(4) Carbon Monoxide
    Information on the health effects of CO can be found in the EPA 
Integrated Science Assessment (ISA) for Carbon Monoxide.\366\ The ISA 
concludes that ambient concentrations of CO are associated with a 
number of adverse health effects.\367\ This section provides a summary 
of the health effects associated with exposure to ambient 
concentrations of CO.\368\
---------------------------------------------------------------------------

    \366\ U.S. EPA, 2010. Integrated Science Assessment for Carbon 
Monoxide (Final Report). U.S. Environmental Protection Agency, 
Washington, DC, EPA/600/R-09/019F, 2010. Available at http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=218686. Docket EPA-HQ-
OAR-2010-0162
    \367\ The ISA evaluates the health evidence associated with 
different health effects, assigning one of five ``weight of 
evidence'' determinations: causal relationship, likely to be a 
causal relationship, suggestive of a causal relationship, inadequate 
to infer a causal relationship, and not likely to be a causal 
relationship. For definitions of these levels of evidence, please 
refer to Section 1.6 of the ISA.
    \368\ Personal exposure includes contributions from many 
sources, and in many different environments. Total personal exposure 
to CO includes both ambient and nonambient components; and both 
components may contribute to adverse health effects.
---------------------------------------------------------------------------

    Human clinical studies of subjects with coronary artery disease 
show a decrease in the time to onset of exercise-induced angina (chest 
pain) and electrocardiogram changes following CO exposure. In addition, 
epidemiologic studies show associations between short-term CO exposure 
and cardiovascular morbidity, particularly increased emergency room 
visits and hospital admissions for coronary heart disease (including 
ischemic heart disease, myocardial infarction, and angina). Some 
epidemiologic evidence is also available for increased hospital 
admissions and emergency room visits for congestive heart failure and 
cardiovascular disease as a whole. The ISA concludes that a causal 
relationship is likely to exist between short-term exposures to CO and 
cardiovascular morbidity. It also concludes that available data are 
inadequate to conclude that a causal relationship exists between long-
term exposures to CO and cardiovascular morbidity.
    Animal studies show various neurological effects with in-utero CO 
exposure. Controlled human exposure studies report inconsistent neural 
and behavioral effects following low-level CO exposures. The ISA 
concludes the evidence is suggestive of a causal relationship with both 
short- and long-term exposure to CO and central nervous system effects.
    A number of epidemiologic and animal toxicological studies cited in 
the ISA have evaluated associations between CO exposure and birth 
outcomes such as preterm birth or cardiac birth defects. The 
epidemiologic studies provide limited evidence of a CO-induced effect 
on preterm births and birth defects, with weak evidence for a decrease 
in birth weight. Animal toxicological studies have found associations 
between perinatal CO exposure and decrements in birth weight, as well 
as other developmental outcomes. The ISA concludes these studies are 
suggestive of a causal relationship between long-term exposures to CO 
and developmental effects and birth outcomes.
    Epidemiologic studies provide evidence of effects on respiratory 
morbidity such as changes in pulmonary function, respiratory symptoms, 
and hospital admissions associated with ambient CO concentrations. A 
limited number of epidemiologic studies considered copollutants such as 
ozone, SO2, and PM in two-pollutant models and found that CO 
risk estimates were generally robust, although this limited evidence 
makes it difficult to disentangle effects attributed to CO itself from 
those of the larger complex air pollution mixture. Controlled human 
exposure studies have not extensively evaluated the effect of CO on 
respiratory morbidity. Animal studies at levels of 50-100 ppm CO show 
preliminary evidence of altered pulmonary vascular remodeling and

[[Page 57305]]

oxidative injury. The ISA concludes that the evidence is suggestive of 
a causal relationship between short-term CO exposure and respiratory 
morbidity, and inadequate to conclude that a causal relationship exists 
between long-term exposure and respiratory morbidity.
    Finally, the ISA concludes that the epidemiologic evidence is 
suggestive of a causal relationship between short-term exposures to CO 
and mortality. Epidemiologic studies provide evidence of an association 
between short-term exposure to CO and mortality, but limited evidence 
is available to evaluate cause-specific mortality outcomes associated 
with CO exposure. In addition, the attenuation of CO risk estimates 
which was often observed in copollutant models contributes to the 
uncertainty as to whether CO is acting alone or as an indicator for 
other combustion-related pollutants. The ISA also concludes that there 
is not likely to be a causal relationship between relevant long-term 
exposures to CO and mortality.
(5) Air Toxics
    Heavy-duty vehicle emissions contribute to ambient levels of air 
toxics known or suspected as human or animal carcinogens, or that have 
noncancer health effects. The population experiences an elevated risk 
of cancer and other noncancer health effects from exposure to the class 
of pollutants known collectively as ``air toxics.'' \369\ These 
compounds include, but are not limited to, benzene, 1,3-butadiene, 
formaldehyde, acetaldehyde, acrolein, diesel particulate matter and 
exhaust organic gases, polycyclic organic matter, and naphthalene. 
These compounds were identified as national or regional risk drivers or 
contributors in the 2005 National-scale Air Toxics Assessment and have 
significant inventory contributions from mobile sources.\370\
---------------------------------------------------------------------------

    \369\ U.S. EPA. 2002 National-Scale Air Toxics Assessment. 
http://www.epa.gov/ttn/atw/nata12002/risksum.html Docket EPA-HQ-OAR-
2010-0162.
    \370\ U.S. EPA 2009. National-Scale Air Toxics Assessment for 
2002. http://www.epa.gov/ttn/atw/nata2002/ Docket EPA-HQ-OAR-2010-
0162.
---------------------------------------------------------------------------

(a) Diesel Exhaust
    Heavy-duty diesel engines emit diesel exhaust, a complex mixture 
composed of carbon dioxide, oxygen, nitrogen, water vapor, carbon 
monoxide, nitrogen compounds, sulfur compounds and numerous low-
molecular-weight hydrocarbons. A number of these gaseous hydrocarbon 
components are individually known to be toxic, including aldehydes, 
benzene and 1,3-butadiene. The diesel particulate matter present in 
diesel exhaust consists mostly of fine particles (low sulfur fuel). Also, there are emissions 
differences between on-road and nonroad engines because the nonroad 
engines are generally of older technology. After being emitted in the 
engine exhaust, diesel exhaust undergoes dilution as well as chemical 
and physical changes in the atmosphere. The lifetime for some of the 
compounds present in diesel exhaust ranges from hours to days.\371\
---------------------------------------------------------------------------

    \371\ U.S. EPA (2002). Health Assessment Document for Diesel 
Engine Exhaust. EPA/600/8-90/057F Office of Research and 
Development, Washington DC. Retrieved on March 17, 2009, from http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=29060. Docket EPA-HQ-
OAR-2010-0162.
---------------------------------------------------------------------------

(i) Diesel Exhaust: Potential Cancer Effects
    In EPA's 2002 Diesel Health Assessment Document (Diesel HAD),\372\ 
exposure to diesel exhaust was classified as likely to be carcinogenic 
to humans by inhalation from environmental exposures, in accordance 
with the revised draft 1996/1999 EPA cancer guidelines. A number of 
other agencies (National Institute for Occupational Safety and Health, 
the International Agency for Research on Cancer, the World Health 
Organization, California EPA, and the U.S. Department of Health and 
Human Services) have made similar classifications. However, EPA also 
concluded in the Diesel HAD that it is not possible currently to 
calculate a cancer unit risk for diesel exhaust due to a variety of 
factors that limit the current studies, such as limited quantitative 
exposure histories in occupational groups investigated for lung cancer.
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    \372\ See U.S. EPA (2002) Diesel HAD, Note 371, at pp. 1-1, 1-2.
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    For the Diesel HAD, EPA reviewed 22 epidemiologic studies on the 
subject of the carcinogenicity of workers exposed to diesel exhaust in 
various occupations, finding increased lung cancer risk, although not 
always statistically significant, in 8 out of 10 cohort studies and 10 
out of 12 case-control studies within several industries. Relative risk 
for lung cancer associated with exposure ranged from 1.2 to 1.5, 
although a few studies show relative risks as high as 2.6. 
Additionally, the Diesel HAD also relied on two independent meta-
analyses, which examined 23 and 30 occupational studies respectively, 
which found statistically significant increases in smoking-adjusted 
relative lung cancer risk associated with exposure to diesel exhaust of 
1.33 to 1.47. These meta-analyses demonstrate the effect of pooling 
many studies and in this case show the positive relationship between 
diesel exhaust exposure and lung cancer across a variety of diesel 
exhaust-exposed occupations.373 374
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    \373\ Bhatia, R., Lopipero, P., Smith, A. (1998). Diesel 
exposure and lung cancer. Epidemiology, 9(1), 84-91. Docket EPA-HQ-
OAR-2010-0162.
    \374\ Lipsett, M. Campleman, S. (1999). Occupational exposure to 
diesel exhaust and lung cancer: a meta-analysis. Am J Public Health, 
80(7), 1009-1017. Docket EPA-HQ-OAR-2010-0162.
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    In the absence of a cancer unit risk, the Diesel HAD sought to 
provide additional insight into the significance of the diesel exhaust-
cancer hazard by estimating possible ranges of risk that might be 
present in the population. An exploratory analysis was used to 
characterize a possible risk range by comparing a typical environmental 
exposure level for highway diesel sources to a selected range of 
occupational exposure levels. The occupationally observed risks were 
then proportionally scaled according to the exposure ratios to obtain 
an estimate of the possible environmental risk. A number of 
calculations are needed to accomplish this, and these can be seen in 
the EPA Diesel HAD. The outcome was that environmental risks from 
diesel exhaust exposure could range from a low of 10-4 to 
10-5 to as high as 10\3\, reflecting the range of 
occupational exposures that could be associated with the relative and 
absolute risk levels observed in the occupational studies. Because of 
uncertainties, the analysis acknowledged that the risks could be lower 
than 10-4 or 10-5, and a zero risk from diesel 
exhaust exposure was not ruled out.
(ii) Diesel Exhaust: Other Health Effects
    Noncancer health effects of acute and chronic exposure to diesel 
exhaust emissions are also of concern to the EPA. EPA derived a diesel 
exhaust reference concentration (RfC) from

[[Page 57306]]

consideration of four well-conducted chronic rat inhalation studies 
showing adverse pulmonary effects.375 376 377 378 The RfC is 
5 [micro]g/m\3\ for diesel exhaust as measured by diesel particulate 
matter. This RfC does not consider allergenic effects such as those 
associated with asthma or immunologic effects. There is growing 
evidence, discussed in the Diesel HAD, that exposure to diesel exhaust 
can exacerbate these effects, but the exposure-response data are 
presently lacking to derive an RfC. The EPA Diesel HAD states, ``With 
[diesel particulate matter] being a ubiquitous component of ambient PM, 
there is an uncertainty about the adequacy of the existing [diesel 
exhaust] noncancer database to identify all of the pertinent [diesel 
exhaust]-caused noncancer health hazards.'' (p. 9-19). The Diesel HAD 
concludes ``that acute exposure to [diesel exhaust] has been associated 
with irritation of the eye, nose, and throat, respiratory symptoms 
(cough and phlegm), and neurophysiological symptoms such as headache, 
lightheadedness, nausea, vomiting, and numbness or tingling of the 
extremities.'' \379\
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    \375\ Ishinishi, N. Kuwabara, N. Takaki, Y., et al. (1988). 
Long-term inhalation experiments on diesel exhaust. In: Diesel 
exhaust and health risks. Results of the HERP studies. Ibaraki, 
Japan: Research Committee for HERP Studies; pp.11-84. Docket EPA-HQ-
OAR-2010-0162.
    \376\ Heinrich, U., Fuhst, R., Rittinghausen, S., et al. (1995). 
Chronic inhalation exposure of Wistar rats and two different strains 
of mice to diesel engine exhaust, carbon black, and titanium 
dioxide. Inhal Toxicol, 7, 553-556. Docket EPA-HQ-OAR-2010-0162.
    \377\ Mauderly, J.L., Jones, R.K., Griffith, W.C., et al. 
(1987). Diesel exhaust is a pulmonary carcinogen in rats exposed 
chronically by inhalation. Fundam. Appl. Toxicol., 9, 208-221. 
Docket EPA-HQ-OAR-2010-0162.
    \378\ Nikula, K.J., Snipes, M.B., Barr, E.B., et al. (1995). 
Comparative pulmonary toxicities and carcinogenicities of 
chronically inhaled diesel exhaust and carbon black in F344 rats. 
Fundam. Appl. Toxicol, 25, 80-94. Docket EPA-HQ-OAR-2010-0162.
    \379\ See U.S. EPA (2002), Diesel HAD at Note 371, at p. 9-9.
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(iii) Ambient PM2.5 Levels and Exposure to Diesel Exhaust PM
    The Diesel HAD also briefly summarizes health effects associated 
with ambient PM and discusses the EPA's annual PM2.5 NAAQS 
of 15 [micro]g/m\3\. There is a much more extensive body of human data 
showing a wide spectrum of adverse health effects associated with 
exposure to ambient PM, of which diesel exhaust is an important 
component. The PM2.5 NAAQS is designed to provide protection 
from the noncancer and premature mortality effects of PM2.5 
as a whole.
(iv) Diesel Exhaust PM Exposures
    Exposure of people to diesel exhaust depends on their various 
activities, the time spent in those activities, the locations where 
these activities occur, and the levels of diesel exhaust pollutants in 
those locations. The major difference between ambient levels of diesel 
particulate and exposure levels for diesel particulate is that exposure 
accounts for a person moving from location to location, proximity to 
the emission source, and whether the exposure occurs in an enclosed 
environment.
Occupational Exposures
    Occupational exposures to diesel exhaust from mobile sources can be 
several orders of magnitude greater than typical exposures in the non-
occupationally exposed population.
    Over the years, diesel particulate exposures have been measured for 
a number of occupational groups. A wide range of exposures has been 
reported, from 2 [mu]g/m\3\ to 1,280 [mu]g/m\3\, for a variety of 
occupations. As discussed in the Diesel HAD, the National Institute of 
Occupational Safety and Health has estimated a total of 1,400,000 
workers are occupationally exposed to diesel exhaust from on-road and 
nonroad vehicles.
Elevated Concentrations and Ambient Exposures in Mobile Source-Impacted 
Areas
    Regions immediately downwind of highways or truck stops may 
experience elevated ambient concentrations of directly-emitted 
PM2.5 from diesel engines. Due to the unique nature of 
highways and truck stops, emissions from a large number of diesel 
engines are concentrated in a small area. Studies near roadways with 
high truck traffic indicate higher concentrations of components of 
diesel PM than other locations.380, 381, 382 High ambient 
particle concentrations have also been reported near trucking 
terminals, truck stops, and bus garages.383, 384, 385 
Additional discussion of exposure and health effects associated with 
traffic is included below in Section 0.
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    \380\ Zhu, Y.; Hinds, W.C.; Kim, S.; Shen, S.; Sioutas, C. 
(2002) Study of ultrafine particles near a major highway with heavy-
duty diesel traffic. Atmospheric Environment 36: 4323-4335. Docket 
EPA-HQ-OAR-2010-0162.
    \381\ Lena, T.S; Ochieng, V.; Holgu[iacute]n-Veras, J.; Kinney, 
P.L. (2002) Elemental carbon and PM2.5 levels in an urban 
community heavily impacted by truck traffic. Environ Health Perspect 
110: 1009-1015. Docket EPA-HQ-OAR-2010-0162.
    \382\ Soliman, A.S.M.; Jacko, J.B.; Palmer, G.M. (2006) 
Development of an empirical model to estimate real-world fine 
particulate matter emission factors: the Traffic Air Quality model. 
J Air & Waste Manage Assoc 56: 1540-1549. Docket EPA-HQ-OAR-2010-
0162.
    \383\ Davis, M.E.; Smith, T.J.; Laden, F.; Hart, J.E.; Ryan, 
L.M.; Garshick, E. (2006) Modeling particle exposure in U.S. 
trucking terminals. Environ Sci Techol 40: 4226-4232. Docket EPA-HQ-
OAR-2010-0162.
    \384\ Miller, T.L.; Fu, J.S.; Hromis, B.; Storey, J.M. (2007) 
Diesel truck idling emissions--measurements at a PM2.5 
hot spot. Proceedings of the Annual Conference of the Transportation 
Research Board, paper no. 07-2609. Docket EPA-HQ-OAR-2010-0162.
    \385\ Ramachandran, G.; Paulsen, D.; Watts, W.; Kittelson, D. 
(2005) Mass, surface area, and number metrics in diesel occupational 
exposure assessment. J Environ Monit 7: 728-735. Docket EPA-HQ-OAR-
2010-0162.
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(b) Benzene
    The EPA's Integrated Risk Information System (IRIS) database lists 
benzene as a known human carcinogen (causing leukemia) by all routes of 
exposure, and concludes that exposure is associated with additional 
health effects, including genetic changes in both humans and animals 
and increased proliferation of bone marrow cells in 
mice.386, 387, 388 EPA states in its IRIS database that data 
indicate a causal relationship between benzene exposure and acute 
lymphocytic leukemia and suggest a relationship between benzene 
exposure and chronic non-lymphocytic leukemia and chronic lymphocytic 
leukemia. The International Agency for Research on Carcinogens (IARC) 
has determined that benzene is a human carcinogen and the U.S. 
Department of Health and Human Services (DHHS) has characterized 
benzene as a known human carcinogen.389, 390
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    \386\ U.S. EPA. 2000. Integrated Risk Information System File 
for Benzene. This material is available electronically at http://www.epa.gov/iris/subst/0276.htm. Docket EPA-HQ-OAR-2010-0162.
    \387\ International Agency for Research on Cancer. 1982. 
Monographs on the evaluation of carcinogenic risk of chemicals to 
humans, Volume 29. Some industrial chemicals and dyestuffs, World 
Health Organization, Lyon, France, p. 345-389. Docket EPA-HQ-OAR-
2010-0162.
    \388\ Irons, R.D.; Stillman, W.S.; Colagiovanni, D.B.; Henry, 
V.A. 1992. Synergistic action of the benzene metabolite hydroquinone 
on myelopoietic stimulating activity of granulocyte/macrophage 
colony-stimulating factor in vitro, Proc. Natl. Acad. Sci. 89:3691-
3695. Docket EPA-HQ-OAR-2010-0162.
    \389\ See IARC, Note 387, above.
    \390\ U.S. Department of Health and Human Services National 
Toxicology Program 11th Report on Carcinogens available at: http://ntp.niehs.nih.gov/go/16183. Docket EPA-HQ-OAR-2010-0162.
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    A number of adverse noncancer health effects including blood 
disorders, such as preleukemia and aplastic anemia, have also been 
associated with long-term exposure to benzene.391, 392

[[Page 57307]]

The most sensitive noncancer effect observed in humans, based on 
current data, is the depression of the absolute lymphocyte count in 
blood.393, 394 In addition, recent work, including studies 
sponsored by the Health Effects Institute (HEI), provides evidence that 
biochemical responses are occurring at lower levels of benzene exposure 
than previously known.395, 396, 397, 398 EPA's IRIS program 
has not yet evaluated these new data.
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    \391\ Aksoy, M. (1989). Hematotoxicity and carcinogenicity of 
benzene. Environ. Health Perspect. 82: 193-197. Docket EPA-HQ-OAR-
2010-0162.
    \392\ Goldstein, B.D. (1988). Benzene toxicity. Occupational 
medicine. State of the Art Reviews. 3: 541-554. Docket EPA-HQ-OAR-
2010-0162.
    \393\ Rothman, N., G.L. Li, M. Dosemeci, W.E. Bechtold, G.E. 
Marti, Y.Z. Wang, M. Linet, L.Q. Xi, W. Lu, M.T. Smith, N. Titenko-
Holland, L.P. Zhang, W. Blot, S.N. Yin, and R.B. Hayes (1996) 
Hematotoxicity among Chinese workers heavily exposed to benzene. Am. 
J. Ind. Med. 29: 236-246. Docket EPA-HQ-OAR-2010-0162.
    \394\ U.S. EPA (2002) Toxicological Review of Benzene (Noncancer 
Effects). Environmental Protection Agency, Integrated Risk 
Information System, Research and Development, National Center for 
Environmental Assessment, Washington DC. This material is available 
electronically at http://www.epa.gov/iris/subst/0276.htm. Docket 
EPA-HQ-OAR-2010-0162.
    \395\ Qu, O.; Shore, R.; Li, G.; Jin, X.; Chen, C.L.; Cohen, B.; 
Melikian, A.; Eastmond, D.; Rappaport, S.; Li, H.; Rupa, D.; 
Suramaya, R.; Songnian, W.; Huifant, Y.; Meng, M.; Winnik, M.; Kwok, 
E.; Li, Y.; Mu, R.; Xu, B.; Zhang, X.; Li, K. (2003) HEI Report 115, 
Validation & Evaluation of Biomarkers in Workers Exposed to Benzene 
in China. Docket EPA-HQ-OAR-2010-0162.
    \396\ Qu, Q., R. Shore, G. Li, X. Jin, L.C. Chen, B. Cohen, et 
al. (2002) Hematological changes among Chinese workers with a broad 
range of benzene exposures. Am. J. Industr. Med. 42: 275-285. Docket 
EPA-HQ-OAR-2010-0162.
    \397\ Lan, Qing, Zhang, L., Li, G., Vermeulen, R., et al. (2004) 
Hematotoxically in Workers Exposed to Low Levels of Benzene. Science 
306: 1774-1776. Docket EPA-HQ-OAR-2010-0162.
    \398\ Turtletaub, K.W. and Mani, C. (2003) Benzene metabolism in 
rodents at doses relevant to human exposure from Urban Air. Research 
Reports Health Effect Inst. Report No.113. Docket EPA-HQ-OAR-2010-
0162.
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(c) 1,3-Butadiene
    EPA has characterized 1,3-butadiene as carcinogenic to humans by 
inhalation.399 400 The IARC has determined that 1,3-
butadiene is a human carcinogen and the U.S. DHHS has characterized 
1,3-butadiene as a known human carcinogen.401 402 There are 
numerous studies consistently demonstrating that 1,3-butadiene is 
metabolized into genotoxic metabolites by experimental animals and 
humans. The specific mechanisms of 1,3-butadiene-induced carcinogenesis 
are unknown; however, the scientific evidence strongly suggests that 
the carcinogenic effects are mediated by genotoxic metabolites. Animal 
data suggest that females may be more sensitive than males for cancer 
effects associated with 1,3-butadiene exposure; there are insufficient 
data in humans from which to draw conclusions about sensitive 
subpopulations. 1,3-butadiene also causes a variety of reproductive and 
developmental effects in mice; no human data on these effects are 
available. The most sensitive effect was ovarian atrophy observed in a 
lifetime bioassay of female mice.\403\
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    \399\ U.S. EPA (2002) Health Assessment of 1,3-Butadiene. Office 
of Research and Development, National Center for Environmental 
Assessment, Washington Office, Washington, DC. Report No. EPA600-P-
98-001F. This document is available electronically at http://www.epa.gov/iris/supdocs/buta-sup.pdf. Docket EPA-HQ-OAR-2010-0162.
    \400\ U.S. EPA (2002) Full IRIS Summary for 1,3-butadiene (CASRN 
106-99-0). Environmental Protection Agency, Integrated Risk 
Information System (IRIS), Research and Development, National Center 
for Environmental Assessment, Washington, DC http://www.epa.gov/iris/subst/0139.htm. Docket EPA-HQ-OAR-2010-0162.
    \401\ International Agency for Research on Cancer (1999) 
Monographs on the evaluation of carcinogenic risk of chemicals to 
humans, Volume 71, Re-evaluation of some organic chemicals, 
hydrazine and hydrogen peroxide and Volume 97 (in preparation), 
World Health Organization, Lyon, France. Docket EPA-HQ-OAR-2010-
0162.
    \402\ U.S. Department of Health and Human Services (2005) 
National Toxicology Program 11th Report on Carcinogens available at: 
ntp.niehs.nih.gov/index.cfm?objectid=32BA9724-F1F6-975E-7FCE50709CB4C932. Docket EPA-HQ-OAR-2010-0162
    \403\ Bevan, C.; Stadler, J.C.; Elliot, G.S.; et al. (1996) 
Subchronic toxicity of 4-vinylcyclohexene in rats and mice by 
inhalation. Fundam. Appl. Toxicol. 32:1-10. Docket EPA-HQ-OAR-2010-
0162.
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(d) Formaldehyde
    Since 1987, EPA has classified formaldehyde as a probable human 
carcinogen based on evidence in humans and in rats, mice, hamsters, and 
monkeys.\404\ EPA is currently reviewing recently published 
epidemiological data. For instance, research conducted by the National 
Cancer Institute found an increased risk of nasopharyngeal cancer and 
lymphohematopoietic malignancies such as leukemia among workers exposed 
to formaldehyde.405 406 In an analysis of the 
lymphohematopoietic cancer mortality from an extended follow-up of 
these workers, the National Cancer Institute confirmed an association 
between lymphohematopoietic cancer risk and peak exposures.\407\ A 
recent National Institute of Occupational Safety and Health study of 
garment workers also found increased risk of death due to leukemia 
among workers exposed to formaldehyde.\408\ Extended follow-up of a 
cohort of British chemical workers did not find evidence of an increase 
in nasopharyngeal or lymphohematopoietic cancers, but a continuing 
statistically significant excess in lung cancers was reported.\409\ 
Recently, the IARC re-classified formaldehyde as a human carcinogen 
(Group 1).\410\
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    \404\ U.S. EPA (1987) Assessment of Health Risks to Garment 
Workers and Certain Home Residents from Exposure to Formaldehyde, 
Office of Pesticides and Toxic Substances, April 1987. Docket EPA-
HQ-OAR-2010-0162.
    \405\ Hauptmann, M.; Lubin, J. H.; Stewart, P. A.; Hayes, R. B.; 
Blair, A. 2003. Mortality from lymphohematopoetic malignancies among 
workers in formaldehyde industries. Journal of the National Cancer 
Institute 95: 1615-1623. Docket EPA-HQ-OAR-2010-0162.
    \406\ Hauptmann, M.; Lubin, J. H.; Stewart, P. A.; Hayes, R. B.; 
Blair, A. 2004. Mortality from solid cancers among workers in 
formaldehyde industries. American Journal of Epidemiology 159: 1117-
1130. Docket EPA-HQ-OAR-2010-0162.
    \407\ Beane Freeman, L. E.; Blair, A.; Lubin, J. H.; Stewart, P. 
A.; Hayes, R. B.; Hoover, R. N.; Hauptmann, M. 2009. Mortality from 
lymphohematopoietic malignancies among workers in formaldehyde 
industries: The National Cancer Institute cohort. J. National Cancer 
Inst. 101: 751-761. Docket EPA-HQ-OAR-2010-0162.
    \408\ Pinkerton, L. E. 2004. Mortality among a cohort of garment 
workers exposed to formaldehyde: an update. Occup. Environ. Med. 61: 
193-200. Docket EPA-HQ-OAR-2010-0162.
    \409\ Coggon, D, EC Harris, J Poole, KT Palmer. 2003. Extended 
follow-up of a cohort of British chemical workers exposed to 
formaldehyde. J National Cancer Inst. 95:1608-1615. Docket EPA-HQ-
OAR-2010-0162.
    \410\ International Agency for Research on Cancer. 2006. 
Formaldehyde, 2-Butoxyethanol and 1-tert-Butoxypropan-2-ol. Volume 
88. (in preparation), World Health Organization, Lyon, France. 
Docket EPA-HQ-OAR-2010-0162
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    Formaldehyde exposure also causes a range of noncancer health 
effects, including irritation of the eyes (burning and watering of the 
eyes), nose and throat. Effects from repeated exposure in humans 
include respiratory tract irritation, chronic bronchitis and nasal 
epithelial lesions such as metaplasia and loss of cilia. Animal studies 
suggest that formaldehyde may also cause airway inflammation--including 
eosinophil infiltration into the airways. There are several studies 
that suggest that formaldehyde may increase the risk of asthma--
particularly in the young.411 412
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    \411\ Agency for Toxic Substances and Disease Registry (ATSDR). 
1999. Toxicological profile for Formaldehyde. Atlanta, GA: U.S. 
Department of Health and Human Services, Public Health Service. 
http://www.atsdr.cdc.gov/toxprofiles/tp111.html Docket EPA-HQ-OAR-
2010-0162.
    \412\ WHO (2002) Concise International Chemical Assessment 
Document 40: Formaldehyde. Published under the joint sponsorship of 
the United Nations Environment Programme, the International Labour 
Organization, and the World Health Organization, and produced within 
the framework of the Inter-Organization Programme for the Sound 
Management of Chemicals. Geneva. Docket EPA-HQ-OAR-2010-0162.
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(e) Acetaldehyde
    Acetaldehyde is classified in EPA's IRIS database as a probable 
human carcinogen, based on nasal tumors in rats, and is considered 
toxic by the inhalation, oral, and intravenous

[[Page 57308]]

routes.\413\ Acetaldehyde is reasonably anticipated to be a human 
carcinogen by the U.S. DHHS in the 11th Report on Carcinogens and is 
classified as possibly carcinogenic to humans (Group 2B) by the 
IARC.414 415 EPA is currently conducting a reassessment of 
cancer risk from inhalation exposure to acetaldehyde.
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    \413\ U.S. EPA. 1991. Integrated Risk Information System File of 
Acetaldehyde. Research and Development, National Center for 
Environmental Assessment, Washington, DC. Available at http://www.epa.gov/iris/subst/0290.htm. Docket EPA-HQ-OAR-2010-0162.
    \414\ U.S. Department of Health and Human Services National 
Toxicology Program 11th Report on Carcinogens available at: 
ntp.niehs.nih.gov/index.cfm?objectid=32BA9724-F1F6-975E-7FCE50709CB4C932. Docket EPA-HQ-OAR-2010-0162.
    \415\ International Agency for Research on Cancer. 1999. Re-
evaluation of some organic chemicals, hydrazine, and hydrogen 
peroxide. IARC Monographs on the Evaluation of Carcinogenic Risk of 
Chemical to Humans, Vol 71. Lyon, France. Docket EPA-HQ-OAR-2010-
0162.
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    The primary noncancer effects of exposure to acetaldehyde vapors 
include irritation of the eyes, skin, and respiratory tract.\416\ In 
short-term (4 week) rat studies, degeneration of olfactory epithelium 
was observed at various concentration levels of acetaldehyde 
exposure.417 418 Data from these studies were used by EPA to 
develop an inhalation reference concentration. Some asthmatics have 
been shown to be a sensitive subpopulation to decrements in functional 
expiratory volume (FEV1 test) and bronchoconstriction upon acetaldehyde 
inhalation.\419\ The agency is currently conducting a reassessment of 
the health hazards from inhalation exposure to acetaldehyde.
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    \416\ See Integrated Risk Information System File of 
Acetaldehyde, Note 413, above.
    \417\ Appleman, L. M., R. A. Woutersen, V. J. Feron, R. N. 
Hooftman, and W. R. F. Notten. 1986. Effects of the variable versus 
fixed exposure levels on the toxicity of acetaldehyde in rats. J. 
Appl. Toxicol. 6: 331-336. Docket EPA-HQ-OAR-2010-0162.
    \418\ Appleman, L.M., R.A. Woutersen, and V.J. Feron. 1982. 
Inhalation toxicity of acetaldehyde in rats. I. Acute and subacute 
studies. Toxicology. 23: 293-297. Docket EPA-HQ-OAR-2010-0162.
    \419\ Myou, S.; Fujimura, M.; Nishi K.; Ohka, T.; and Matsuda, 
T. 1993. Aerosolized acetaldehyde induces histamine-mediated 
bronchoconstriction in asthmatics. Am. Rev. Respir.Dis.148(4 Pt 1): 
940-3. Docket EPA-HQ-OAR-2010-0162.
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(f) Acrolein
    Acrolein is extremely acrid and irritating to humans when inhaled, 
with acute exposure resulting in upper respiratory tract irritation, 
mucus hypersecretion and congestion. The intense irritancy of this 
carbonyl has been demonstrated during controlled tests in human 
subjects, who suffer intolerable eye and nasal mucosal sensory 
reactions within minutes of exposure.\420\ These data and additional 
studies regarding acute effects of human exposure to acrolein are 
summarized in EPA's 2003 IRIS Human Health Assessment for 
acrolein.\421\ Evidence available from studies in humans indicate that 
levels as low as 0.09 ppm (0.21 mg/m\3\) for five minutes may elicit 
subjective complaints of eye irritation with increasing concentrations 
leading to more extensive eye, nose and respiratory symptoms.\422\ 
Lesions to the lungs and upper respiratory tract of rats, rabbits, and 
hamsters have been observed after subchronic exposure to acrolein.\423\ 
Acute exposure effects in animal studies report bronchial hyper-
responsiveness.\424\ In a recent study, the acute respiratory irritant 
effects of exposure to 1.1 ppm acrolein were more pronounced in mice 
with allergic airway disease by comparison to non-diseased mice which 
also showed decreases in respiratory rate.\425\ Based on these animal 
data and demonstration of similar effects in humans (e.g., reduction in 
respiratory rate), individuals with compromised respiratory function 
(e.g., emphysema, asthma) are expected to be at increased risk of 
developing adverse responses to strong respiratory irritants such as 
acrolein.
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    \420\ U.S. EPA (U.S. Environmental Protection Agency). (2003) 
Toxicological review of acrolein in support of summary information 
on Integrated Risk Information System (IRIS) National Center for 
Environmental Assessment, Washington, DC. EPA/635/R-03/003. p. 10. 
Available online at: http://www.epa.gov/ncea/iris/toxreviews/0364tr.pdf. Docket EPA-HQ-OAR-2010-0162.
    \421\ See U.S. EPA 2003 Toxicological review of acrolein, Note 
420, above.
    \422\ See U.S. EPA 2003 Toxicological review of acrolein, Note 
420, at p. 11.
    \423\ Integrated Risk Information System File of Acrolein. 
Office of Research and Development, National Center for 
Environmental Assessment, Washington, DC. This material is available 
at http://www.epa.gov/iris/subst/0364.htm Docket EPA-HQ-OAR-2010-
0162.
    \424\ See U.S. 2003 Toxicological review of acrolein, Note 420, 
at p. 15.
    \425\ Morris JB, Symanowicz PT, Olsen JE, et al. 2003. Immediate 
sensory nerve-mediated respiratory responses to irritants in healthy 
and allergic airway-diseased mice. J Appl Physiol 94(4):1563-1571. 
Docket EPA-HQ-OAR-2010-0162.
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    EPA determined in 2003 that the human carcinogenic potential of 
acrolein could not be determined because the available data were 
inadequate. No information was available on the carcinogenic effects of 
acrolein in humans and the animal data provided inadequate evidence of 
carcinogenicity.\426\ The IARC determined in 1995 that acrolein was not 
classifiable as to its carcinogenicity in humans.\427\
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    \426\ U.S. EPA. 2003. Integrated Risk Information System File of 
Acrolein. Research and Development, National Center for 
Environmental Assessment, Washington, DC. This material is available 
at http://www.epa.gov/iris/subst/0364.htm Docket EPA-HQ-OAR-2010-
0162.
    \427\ International Agency for Research on Cancer. 1995. 
Monographs on the evaluation of carcinogenic risk of chemicals to 
humans, Volume 63. Dry cleaning, some chlorinated solvents and other 
industrial chemicals, World Health Organization, Lyon, France. 
Docket EPA-HQ-OAR-2010-0162.
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(g) Polycyclic Organic Matter
    The term polycyclic organic matter (POM) defines a broad class of 
compounds that includes the polycyclic aromatic hydrocarbon compounds 
(PAHs). One of these compounds, naphthalene, is discussed separately 
below. POM compounds are formed primarily from combustion and are 
present in the atmosphere in gas and particulate form. Cancer is the 
major concern from exposure to POM. Epidemiologic studies have reported 
an increase in lung cancer in humans exposed to diesel exhaust, coke 
oven emissions, roofing tar emissions, and cigarette smoke; all of 
these mixtures contain POM compounds.\428,429\ Animal studies have 
reported respiratory tract tumors from inhalation exposure to 
benzo[a]pyrene and alimentary tract and liver tumors from oral exposure 
to benzo[a]pyrene. EPA has classified seven PAHs (benzo[a]pyrene, 
benz[a]anthracene, chrysene, benzo[b]fluoranthene, 
benzo[k]fluoranthene, dibenz[a,h]anthracene, and indeno[1,2,3-
cd]pyrene) as Group B2, probable human carcinogens.\430\ Recent studies 
have found that maternal exposures to PAHs in a population of pregnant 
women were associated with several adverse birth outcomes, including 
low birth weight and reduced length at birth, as well as impaired 
cognitive development in preschool children (3 years of 
age).\431,432\EPA has not yet evaluated these recent studies.
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    \428\ Agency for Toxic Substances and Disease Registry (ATSDR). 
1995. Toxicological profile for Polycyclic Aromatic Hydrocarbons 
(PAHs). Atlanta, GA: U.S. Department of Health and Human Services, 
Public Health Service. Available electronically at http://www.atsdr.cdc.gov/ToxProfiles/TP.asp?id=122&tid=25.
    \429\ U.S. EPA (2002). Health Assessment Document for Diesel 
Engine Exhaust. EPA/600/8-90/057F Office of Research and 
Development, Washington DC. http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=29060. Docket EPA-HQ-OAR-2010-0162.
    \430\ U.S. EPA (1997). Integrated Risk Information System File 
of indeno(1,2,3-cd)pyrene. Research and Development, National Center 
for Environmental Assessment, Washington, DC. This material is 
available electronically at http://www.epa.gov/ncea/iris/subst/0457.htm.
    \431\ Perera, F.P.; Rauh, V.; Tsai, W-Y.; et al. (2002) Effect 
of transplacental exposure to environmental pollutants on birth 
outcomes in a multiethnic population. Environ Health Perspect. 111: 
201-205.
    \432\ Perera, F.P.; Rauh, V.; Whyatt, R.M.; Tsai, W.Y.; Tang, 
D.; Diaz, D.; Hoepner, L.; Barr, D.; Tu, Y.H.; Camann, D.; Kinney, 
P. (2006) Effect of prenatal exposure to airborne polycyclic 
aromatic hydrocarbons on neurodevelopment in the first 3 years of 
life among inner-city children. Environ Health Perspect 114: 1287-
1292.

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[[Page 57309]]

(h) Naphthalene
    Naphthalene is found in small quantities in gasoline and diesel 
fuels. Naphthalene emissions have been measured in larger quantities in 
both gasoline and diesel exhaust compared with evaporative emissions 
from mobile sources, indicating it is primarily a product of 
combustion. EPA released an external review draft of a reassessment of 
the inhalation carcinogenicity of naphthalene based on a number of 
recent animal carcinogenicity studies.\433\ The draft reassessment 
completed external peer review.\434\ Based on external peer review 
comments received, additional analyses are being undertaken. This 
external review draft does not represent official agency opinion and 
was released solely for the purposes of external peer review and public 
comment. The National Toxicology Program listed naphthalene as 
``reasonably anticipated to be a human carcinogen'' in 2004 on the 
basis of bioassays reporting clear evidence of carcinogenicity in rats 
and some evidence of carcinogenicity in mice.\435\ California EPA has 
released a new risk assessment for naphthalene, and the IARC has 
reevaluated naphthalene and re-classified it as Group 2B: possibly 
carcinogenic to humans.\436\ Naphthalene also causes a number of 
chronic non-cancer effects in animals, including abnormal cell changes 
and growth in respiratory and nasal tissues.\437\
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    \433\ U. S. EPA. 2004. Toxicological Review of Naphthalene 
(Reassessment of the Inhalation Cancer Risk), Environmental 
Protection Agency, Integrated Risk Information System, Research and 
Development, National Center for Environmental Assessment, 
Washington, DC. This material is available electronically at http://www.epa.gov/iris/subst/0436.htm. Docket EPA-HQ-OAR-2010-0162.
    \434\ Oak Ridge Institute for Science and Education. (2004). 
External Peer Review for the IRIS Reassessment of the Inhalation 
Carcinogenicity of Naphthalene. August 2004. http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=84403 Docket EPA-HQ-OAR-2010-0162.
    \435\ National Toxicology Program (NTP). (2004). 11th Report on 
Carcinogens. Public Health Service, U.S. Department of Health and 
Human Services, Research Triangle Park, NC. Available from: http://ntp-server.niehs.nih.gov. Docket EPA-HQ-OAR-2010-0162.
    \436\ International Agency for Research on Cancer. (2002). 
Monographs on the Evaluation of the Carcinogenic Risk of Chemicals 
for Humans. Vol. 82. Lyon, France. Docket EPA-HQ-OAR-2010-0162.
    \437\ U. S. EPA. 1998. Toxicological Review of Naphthalene, 
Environmental Protection Agency, Integrated Risk Information System, 
Research and Development, National Center for Environmental 
Assessment, Washington, DC. This material is available 
electronically at http://www.epa.gov/iris/subst/0436.htm Docket EPA-
HQ-OAR-2010-0162.
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(i) Other Air Toxics
    In addition to the compounds described above, other compounds in 
gaseous hydrocarbon and PM emissions from heavy-duty vehicles will be 
affected by this final action. Mobile source air toxic compounds that 
would potentially be impacted include ethylbenzene, propionaldehyde, 
toluene, and xylene. Information regarding the health effects of these 
compounds can be found in EPA's IRIS database.\438\
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    \438\ U.S. EPA Integrated Risk Information System (IRIS) 
database is available at: http://www.epa.gov/iris.
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(j) Exposure and Health Effects Associated with Traffic
    Populations who live, work, or attend school near major roads 
experience elevated exposure concentrations to a wide range of air 
pollutants, as well as higher risks for a number of adverse health 
effects. While the previous sections of this preamble have focused on 
the health effects associated with individual criteria pollutants or 
air toxics, this section discusses the mixture of different exposures 
near major roadways, rather than the effects of any single pollutant. 
As such, this section emphasizes traffic-related air pollution, in 
general, as the relevant indicator of exposure rather than any 
particular pollutant.
    Concentrations of many traffic-generated air pollutants are 
elevated for up to 300-500 meters downwind of roads with high traffic 
volumes.\439\ Numerous sources on roads contribute to elevated roadside 
concentrations, including exhaust and evaporative emissions, and 
resuspension of road dust and tire and brake wear. Concentrations of 
several criteria and hazardous air pollutants are elevated near major 
roads. Furthermore, different semi-volatile organic compounds and 
chemical components of particulate matter, including elemental carbon, 
organic material, and trace metals, have been reported at higher 
concentrations near major roads.
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    \439\ Zhou, Y.; Levy, J.I. (2007) Factors influencing the 
spatial extent of mobile source air pollution impacts: A meta-
analysis. BMC Public Health 7:89. doi:10.1186/1471-2458-7-89 Docket 
EPA-HQ-OAR-2010-0162.
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    Populations near major roads experience greater risk of certain 
adverse health effects. The Health Effects Institute published a report 
on the health effects of traffic-related air pollution.\440\ It 
concluded that evidence is ``sufficient to infer the presence of a 
causal association'' between traffic exposure and exacerbation of 
childhood asthma symptoms. The HEI report also concludes that the 
evidence is either ``sufficient'' or ``suggestive but not sufficient'' 
for a causal association between traffic exposure and new childhood 
asthma cases. A review of asthma studies by Salam et al. (2008) reaches 
similar conclusions.\441\ The HEI report also concludes that there is 
``suggestive'' evidence for pulmonary function deficits associated with 
traffic exposure, but concluded that there is ``inadequate and 
insufficient'' evidence for causal associations with respiratory health 
care utilization, adult-onset asthma, chronic obstructive pulmonary 
disease symptoms, and allergy. A review by Holguin (2008) notes that 
the effects of traffic on asthma may be modified by nutrition status, 
medication use, and genetic factors.\442\
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    \440\ HEI Panel on the Health Effects of Air Pollution. (2010) 
Traffic-related air pollution: a critical review of the literature 
on emissions, exposure, and health effects. [Online at http://www.healtheffects.org] Docket EPA-HQ-OAR-2010-0162.
    \441\ Salam, M.T.; Islam, T.; Gilliland, F.D. (2008) Recent 
evidence for adverse effects of residential proximity to traffic 
sources on asthma. Current Opin Pulm Med 14: 3-8. Docket EPA-HQ-OAR-
2010-0162.
    \442\ Holguin, F. (2008) Traffic, outdoor air pollution, and 
asthma. Immunol Allergy Clinics North Am 28: 577-588. Docket EPA-HQ-
OAR-2010-0162.
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    The HEI report also concludes that evidence is ``suggestive'' of a 
causal association between traffic exposure and all-cause and 
cardiovascular mortality. There is also evidence of an association 
between traffic-related air pollutants and cardiovascular effects such 
as changes in heart rhythm, heart attack, and cardiovascular disease. 
The HEI report characterizes this evidence as ``suggestive'' of a 
causal association, and an independent epidemiological literature 
review by Adar and Kaufman (2007) concludes that there is ``consistent 
evidence'' linking traffic-related pollution and adverse cardiovascular 
health outcomes.\443\
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    \443\ Adar, S.D.; Kaufman, J.D. (2007) Cardiovascular disease 
and air pollutants: evaluating and improving epidemiological data 
implicating traffic exposure. Inhal Toxicol 19: 135-149. Docket EPA-
HQ-OAR-2010-0162.
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    Some studies have reported associations between traffic exposure 
and other health effects, such as birth outcomes (e.g., low birth 
weight) and childhood cancer. The HEI report concludes that there is 
currently ``inadequate and insufficient'' evidence for a causal 
association between these effects and traffic exposure. A review by 
Raaschou-Nielsen and Reynolds (2006) concluded that evidence of an 
association between childhood cancer and traffic-related air pollutants 
is weak,

[[Page 57310]]

but noted the inability to draw firm conclusions based on limited 
evidence.\444\
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    \444\ Raaschou-Nielsen, O.; Reynolds, P. (2006) Air pollution 
and childhood cancer: a review of the epidemiological literature. 
Int J Cancer 118: 2920-2929. Docket EPA-HQ-OAR-2010-0162.
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    There is a large population in the United States living in close 
proximity of major roads. According to the Census Bureau's American 
Housing Survey for 2007, approximately 20 million residences in the 
United States, 15.6 percent of all homes, are located within 300 feet 
(91 m) of a highway with 4+ lanes, a railroad, or an airport.\445\ 
Therefore, at current population of approximately 309 million, assuming 
that population and housing are similarly distributed, there are over 
48 million people in the United States living near such sources. The 
HEI report also notes that in two North American cities, Los Angeles 
and Toronto, over 40 percent of each city's population live within 500 
meters of a highway or 100 meters of a major road. It also notes that 
about 33 percent of each city's population resides within 50 meters of 
major roads. Together, the evidence suggests that a large U.S. 
population lives in areas with elevated traffic-related air pollution.
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    \445\ U.S. Census Bureau (2008) American Housing Survey for the 
United States in 2007. Series H-150 (National Data), Table 1A-7. 
[Accessed at http://www.census.gov/hhes/www/housing/ahs/ahs07/ahs07.html on January 22, 2009] Docket EPA-HQ-OAR-2010-0162.
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    People living near roads are often socioeconomically disadvantaged. 
According to the 2007 American Housing Survey, a renter-occupied 
property is over twice as likely as an owner-occupied property to be 
located near a highway with 4+ lanes, railroad or airport. In the same 
survey, the median household income of rental housing occupants was 
less than half that of owner-occupants ($28,921/$59,886). Numerous 
studies in individual urban areas report higher levels of traffic-
related air pollutants in areas with high minority or poor 
populations.446 447 448
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    \446\ Lena, T.S.; Ochieng, V.; Carter, M.; Holgu[iacute]n-Veras, 
J.; Kinney, P.L. (2002) Elemental carbon and PM2.5 levels 
in an urban community heavily impacted by truck traffic. Environ 
Health Perspect 110: 1009-1015. Docket EPA-HQ-OAR-2010-0162.
    \447\ Wier, M.; Sciammas, C.; Seto, E.; Bhatia, R.; Rivard, T. 
(2009) Health, traffic, and environmental justice: collaborative 
research and community action in San Francisco, California. Am J 
Public Health 99: S499-S504. Docket EPA-HQ-OAR-2010-0162.
    \448\ Forkenbrock, D.J. and L.A. Schweitzer, Environmental 
Justice and Transportation Investment Policy. Iowa City: University 
of Iowa, 1997. Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    Students may also be exposed in situations where schools are 
located near major roads. In a study of nine metropolitan areas across 
the United States, Appatova et al. (2008) found that on average greater 
than 33 percent of schools were located within 400 m of an Interstate, 
U.S., or state highway, while 12 percent were located within 100 
m.\449\ The study also found that among the metropolitan areas studied, 
schools in the Eastern United States were more often sited near major 
roadways than schools in the Western United States.
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    \449\ Appatova, A.S.; Ryan, P.H.; LeMasters, G.K.; Grinshpun, 
S.A. (2008) Proximal exposure of public schools and students to 
major roadways: a nationwide U.S. survey. J Environ Plan Mgmt Docket 
EPA-HQ-OAR-2010-0162.
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    Demographic studies of students in schools near major roadways 
suggest that this population is more likely than the general student 
population to be of non-white race or Hispanic ethnicity, and more 
often live in low socioeconomic status locations.450 451 452 
There is some inconsistency in the evidence, which may be due to 
different local development patterns and measures of traffic and 
geographic scale used in the studies.\449\
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    \450\ Green, R.S.; Smorodinsky, S.; Kim, J.J.; McLaughlin, R.; 
Ostro, B. (2004) Proximity of California public schools to busy 
roads. Environ Health Perspect 112: 61-66. Docket EPA-HQ-OAR-2010-
0162.
    \451\ Houston, D.; Ong, P.; Wu, J.; Winer, A. (2006) Proximity 
of licensed child care facilities to near-roadway vehicle pollution. 
Am J Public Health 96: 1611-1617. Docket EPA-HQ-OAR-2010-0162.
    \452\ Wu, Y.; Batterman, S. (2006) Proximity of schools in 
Detroit, Michigan to automobile and truck traffic. J Exposure Sci 
Environ Epidemiol 16: 457-470. Docket EPA-HQ-OAR-2010-0162.
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C. Environmental Effects of Non-GHG Pollutants

    In this section we discuss some of the environmental effects of PM 
and its precursors such as visibility impairment, atmospheric 
deposition, and materials damage and soiling, as well as environmental 
effects associated with the presence of ozone in the ambient air, such 
as impacts on plants, including trees, agronomic crops and urban 
ornamentals, and environmental effects associated with air toxics.
(1) Visibility
    Visibility can be defined as the degree to which the atmosphere is 
transparent to visible light.\453\ Visibility impairment is caused by 
light scattering and absorption by suspended particles and gases. 
Visibility is important because it has direct significance to people's 
enjoyment of daily activities in all parts of the country. Individuals 
value good visibility for the well-being it provides them directly, 
where they live and work, and in places where they enjoy recreational 
opportunities. Visibility is also highly valued in significant natural 
areas, such as national parks and wilderness areas, and special 
emphasis is given to protecting visibility in these areas. For more 
information on visibility see the final 2009 PM ISA.\454\
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    \453\ National Research Council, 1993. Protecting Visibility in 
National Parks and Wilderness Areas. National Academy of Sciences 
Committee on Haze in National Parks and Wilderness Areas. National 
Academy Press, Washington, DC. Docket EPA-HQ-OAR-2010-0162. This 
book can be viewed on the National Academy Press Web site at http://www.nap.edu/books/0309048443/html/.
    \454\ See U.S. EPA 2009 Final PM ISA, Note 355.
---------------------------------------------------------------------------

    EPA is pursuing a two-part strategy to address visibility 
impairment. First, EPA developed the regional haze program (64 FR 
35714) which was put in place in July 1999 to protect the visibility in 
Mandatory Class I Federal areas. There are 156 national parks, forests 
and wilderness areas categorized as Mandatory Class I Federal areas (62 
FR 38680-38681, July 18, 1997). These areas are defined in CAA section 
162 as those national parks exceeding 6,000 acres, wilderness areas and 
memorial parks exceeding 5,000 acres, and all international parks which 
were in existence on August 7, 1977. Second, EPA has concluded that 
PM2.5 causes adverse effects on visibility in other areas 
that are not protected by the Regional Haze Rule, depending on 
PM2.5 concentrations and other factors that control their 
visibility impact effectiveness such as dry chemical composition and 
relative humidity (i.e., an indicator of the water composition of the 
particles), and has set secondary PM2.5 standards to address 
these areas. The existing annual primary and secondary PM2.5 
standards have been remanded by the DC Circuit (see American Farm 
Bureau v. EPA, 559 F. 3d 512 (DC Cir. 2009) and are being addressed in 
the currently ongoing PM NAAQS review.
(2) Plant and Ecosystem Effects of Ozone
    Elevated ozone levels contribute to environmental effects, with 
impacts to plants and ecosystems being of most concern. Ozone can 
produce both acute and chronic injury in sensitive species depending on 
the concentration level and the duration of the exposure. Ozone effects 
also tend to accumulate over the growing season of the plant, so that 
even low concentrations experienced for a longer duration have the 
potential to create chronic stress on vegetation. Ozone damage to 
plants includes visible injury to leaves and impaired photosynthesis, 
both of which can lead to reduced plant growth and reproduction, 
resulting in reduced crop yields, forestry production, and use of

[[Page 57311]]

sensitive ornamentals in landscaping. In addition, the impairment of 
photosynthesis, the process by which the plant makes carbohydrates (its 
source of energy and food), can lead to a subsequent reduction in root 
growth and carbohydrate storage below ground, resulting in other, more 
subtle plant and ecosystems impacts.
    These latter impacts include increased susceptibility of plants to 
insect attack, disease, harsh weather, interspecies competition and 
overall decreased plant vigor. The adverse effects of ozone on forest 
and other natural vegetation can potentially lead to species shifts and 
loss from the affected ecosystems, resulting in a loss or reduction in 
associated ecosystem goods and services. Lastly, visible ozone injury 
to leaves can result in a loss of aesthetic value in areas of special 
scenic significance like national parks and wilderness areas. The final 
2006 Ozone Air Quality Criteria Document presents more detailed 
information on ozone effects on vegetation and ecosystems.
(3) Atmospheric Deposition
    Wet and dry deposition of ambient particulate matter delivers a 
complex mixture of metals (e.g., mercury, zinc, lead, nickel, aluminum, 
cadmium), organic compounds (e.g., polycyclic organic matter, dioxins, 
furans) and inorganic compounds (e.g., nitrate, sulfate) to terrestrial 
and aquatic ecosystems. The chemical form of the compounds deposited 
depends on a variety of factors including ambient conditions (e.g., 
temperature, humidity, oxidant levels) and the sources of the material. 
Chemical and physical transformations of the compounds occur in the 
atmosphere as well as the media onto which they deposit. These 
transformations in turn influence the fate, bioavailability and 
potential toxicity of these compounds. Atmospheric deposition has been 
identified as a key component of the environmental and human health 
hazard posed by several pollutants including mercury, dioxin and 
PCBs.\455\
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    \455\ U.S. EPA (2000) Deposition of Air Pollutants to the Great 
Waters: Third Report to Congress. Office of Air Quality Planning and 
Standards. EPA-453/R-00-0005. Docket EPA-HQ-OAR-2010-0162.
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    Adverse impacts on water quality can occur when atmospheric 
contaminants deposit to the water surface or when material deposited on 
the land enters a waterbody through runoff. Potential impacts of 
atmospheric deposition to waterbodies include those related to both 
nutrient and toxic inputs. Adverse effects to human health and welfare 
can occur from the addition of excess nitrogen via atmospheric 
deposition. The nitrogen-nutrient enrichment contributes to toxic algae 
blooms and zones of depleted oxygen, which can lead to fish kills, 
frequently in coastal waters. Deposition of heavy metals or other 
toxics may lead to the human ingestion of contaminated fish, impairment 
of drinking water, damage to the marine ecology, and limits to 
recreational uses. Several studies have been conducted in U.S. coastal 
waters and in the Great Lakes Region in which the role of ambient PM 
deposition and runoff is investigated.456 457 458 459 460
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    \456\ U.S. EPA (2004) National Coastal Condition Report II. 
Office of Research and Development/Office of Water. EPA-620/R-03/
002. Docket EPA-HQ-OAR-2010-0162.
    \457\ Gao, Y., E.D. Nelson, M.P. Field, et al. 2002. 
Characterization of atmospheric trace elements on PM2.5 
particulate matter over the New York-New Jersey harbor estuary. 
Atmos. Environ. 36: 1077-1086. Docket EPA-HQ-OAR-2010-0162.
    \458\ Kim, G., N. Hussain, J.R. Scudlark, and T.M. Church. 2000. 
Factors influencing the atmospheric depositional fluxes of stable 
Pb, 210Pb, and 7Be into Chesapeake Bay. J. Atmos. Chem. 36: 65-79. 
Docket EPA-HQ-OAR-2010-0162.
    \459\ Lu, R., R.P. Turco, K. Stolzenbach, et al. 2003. Dry 
deposition of airborne trace metals on the Los Angeles Basin and 
adjacent coastal waters. J. Geophys. Res. 108(D2, 4074): AAC 11-1 to 
11-24. Docket EPA-HQ-OAR-2010-0162.
    \460\ Marvin, C.H., M.N. Charlton, E.J. Reiner, et al. 2002. 
Surficial sediment contamination in Lakes Erie and Ontario: A 
comparative analysis. J. Great Lakes Res. 28(3): 437-450. Docket 
EPA-HQ-OAR-2010-0162.
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    Atmospheric deposition of nitrogen and sulfur contributes to 
acidification, altering biogeochemistry and affecting animal and plant 
life in terrestrial and aquatic ecosystems across the United States. 
The sensitivity of terrestrial and aquatic ecosystems to acidification 
from nitrogen and sulfur deposition is predominantly governed by 
geology. Prolonged exposure to excess nitrogen and sulfur deposition in 
sensitive areas acidifies lakes, rivers and soils. Increased acidity in 
surface waters creates inhospitable conditions for biota and affects 
the abundance and nutritional value of preferred prey species, 
threatening biodiversity and ecosystem function. Over time, acidifying 
deposition also removes essential nutrients from forest soils, 
depleting the capacity of soils to neutralize future acid loadings and 
negatively affecting forest sustainability. Major effects include a 
decline in sensitive forest tree species, such as red spruce (Picea 
rubens) and sugar maple (Acer saccharum), and a loss of biodiversity of 
fishes, zooplankton, and macro invertebrates.
    In addition to the role nitrogen deposition plays in acidification, 
nitrogen deposition also leads to nutrient enrichment and altered 
biogeochemical cycling. In aquatic systems increased nitrogen can alter 
species assemblages and cause eutrophication. In terrestrial systems 
nitrogen loading can lead to loss of nitrogen sensitive lichen species, 
decreased biodiversity of grasslands, meadows and other sensitive 
habitats, and increased potential for invasive species. For a broader 
explanation of the topics treated here, refer to the description in 
Section 7.1.2 of the RIA.
    Adverse impacts on soil chemistry and plant life have been observed 
for areas heavily influenced by atmospheric deposition of nutrients, 
metals and acid species, resulting in species shifts, loss of 
biodiversity, forest decline and damage to forest productivity. 
Potential impacts also include adverse effects to human health through 
ingestion of contaminated vegetation or livestock (as in the case for 
dioxin deposition), reduction in crop yield, and limited use of land 
due to contamination.
    Atmospheric deposition of pollutants can reduce the aesthetic 
appeal of buildings and culturally important articles through soiling, 
and can contribute directly (or in conjunction with other pollutants) 
to structural damage by means of corrosion or erosion. Atmospheric 
deposition may affect materials principally by promoting and 
accelerating the corrosion of metals, by degrading paints, and by 
deteriorating building materials such as concrete and limestone. 
Particles contribute to these effects because of their electrolytic, 
hygroscopic, and acidic properties, and their ability to adsorb 
corrosive gases (principally sulfur dioxide).
(4) Environmental Effects of Air Toxics
    Emissions from producing, transporting and combusting fuel 
contribute to ambient levels of pollutants that contribute to adverse 
effects on vegetation. Volatile organic compounds, some of which are 
considered air toxics, have long been suspected to play a role in 
vegetation damage.\461\ In laboratory experiments, a wide range of 
tolerance to VOCs has been observed.\462\ Decreases in harvested seed 
pod weight have been reported for the more sensitive plants, and some 
studies have reported effects on seed germination, flowering and fruit

[[Page 57312]]

ripening. Effects of individual VOCs or their role in conjunction with 
other stressors (e.g., acidification, drought, temperature extremes) 
have not been well studied. In a recent study of a mixture of VOCs 
including ethanol and toluene on herbaceous plants, significant effects 
on seed production, leaf water content and photosynthetic efficiency 
were reported for some plant species.\463\
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    \461\ U.S. EPA. 1991. Effects of organic chemicals in the 
atmosphere on terrestrial plants. EPA/600/3-91/001. Docket EPA-HQ-
OAR-2010-0162.
    \462\ Cape JN, ID Leith, J Binnie, J Content, M Donkin, M 
Skewes, DN Price AR Brown, AD Sharpe. 2003. Effects of VOCs on 
herbaceous plants in an open-top chamber experiment. Environ. 
Pollut. 124:341-343. Docket EPA-HQ-OAR-2010-0162.
    \463\ Cape JN, ID Leith, J Binnie, J Content, M Donkin, M 
Skewes, DN Price AR Brown, AD Sharpe. 2003. Effects of VOCs on 
herbaceous plants in an open-top chamber experiment. Environ. 
Pollut. 124:341-343. Docket EPA-HQ-OAR-2010-0162.
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    Research suggests an adverse impact of vehicle exhaust on plants, 
which has in some cases been attributed to aromatic compounds and in 
other cases to nitrogen oxides.464 465 466 The impacts of 
VOCs on plant reproduction may have long-term implications for 
biodiversity and survival of native species near major roadways. Most 
of the studies of the impacts of VOCs on vegetation have focused on 
short-term exposure and few studies have focused on long-term effects 
of VOCs on vegetation and the potential for metabolites of these 
compounds to affect herbivores or insects.
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    \464\ Viskari E-L. 2000. Epicuticular wax of Norway spruce 
needles as indicator of traffic pollutant deposition. Water, Air, 
and Soil Pollut. 121:327-337. Docket EPA-HQ-OAR-2010-0162.
    \465\ Ugrekhelidze D, F Korte, G Kvesitadze. 1997. Uptake and 
transformation of benzene and toluene by plant leaves. Ecotox. 
Environ. Safety 37:24-29. Docket EPA-HQ-OAR-2010-0162.
    \466\ Kammerbauer H, H Selinger, R Rommelt, A Ziegler-Jons, D 
Knoppik, B Hock. 1987. Toxic components of motor vehicle emissions 
for the spruce Picea abies. Environ. Pollut. 48:235-243. Docket EPA-
HQ-OAR-2010-0162.
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D. Air Quality Impacts of Non-GHG Pollutants

    Air quality modeling was performed to assess the impact of the 
heavy-duty vehicle standards on criteria and air toxic pollutants. In 
this section, we present information on current modeled levels of 
pollution as well as projections for 2030, with respect to ambient 
PM2.5, ozone, selected air toxics, visibility levels and 
nitrogen and sulfur deposition. The results are discussed in more 
detail in Section 8.2 of the RIA.
    We used the Community Multi-scale Air Quality (CMAQ) photochemical 
model, version 4.7.1, for our analysis. This version of CMAQ includes a 
number of improvements to previous versions of the model. These 
improvements are discussed in Section 8.2.2 of the RIA.
(1) Ozone
(a) Current Levels
    8-hour ozone concentrations exceeding the level of the ozone NAAQS 
occur in many parts of the country. In 2008, the EPA amended the ozone 
NAAQS (73 FR 16436, March 27, 2008). The final 2008 ozone NAAQS rule 
set forth revisions to the previous 1997 NAAQS for ozone to provide 
increased protection of public health and welfare. On January 6, 2010, 
EPA proposed to reconsider the 2008 ozone NAAQS to ensure that they are 
requisite to protect public health with an ample margin of safety, and 
requisite to protect public welfare (75 FR 2938, January 19, 2010). EPA 
intends to complete the reconsideration by July 31, 2011. If, as a 
result of the reconsideration, EPA promulgates different ozone 
standards, the new 2011 ozone standards would replace the 2008 ozone 
standards and the requirement to designate areas for the replaced 2008 
standards would no longer apply.
    As of April 21, 2011 there are 44 areas designated as nonattainment 
for the 1997 8-hour ozone NAAQS, comprising 242 full or partial 
counties with a total population of over 118 million people. These 
numbers do not include the people living in areas where there is a 
future risk of failing to maintain or attain the 1997 8-hour ozone 
NAAQS. The numbers above likely underestimate the number of counties 
that are not meeting the ozone NAAQS because the nonattainment areas 
associated with the more stringent 2008 8-hour ozone NAAQS have not yet 
been designated. Table VII-7 provides an estimate, based on 2006-08 air 
quality data, of the counties with design values greater than the 2008 
8-hour ozone NAAQS of 0.075 ppm.

  Table VII-7--Counties With Design Values Greater Than the Ozone NAAQS
------------------------------------------------------------------------
                                             Number of
                Standard                     counties     Population \a\
------------------------------------------------------------------------
1997 Ozone Standard: counties within the             266     122,343,799
 54 areas currently designated as
 nonattainment (as of 1/6/10)...........
2008 Ozone Standard: additional counties             156      36,678,478
 that would not meet the 2008 NAAQS
 (based on 2006-2008 air quality data)
 \b\....................................
    Total...............................             422     159,022,277
------------------------------------------------------------------------
Notes:
\a\ Population numbers are from 2000 census data.
\b\ Area designations for the 2008 ozone NAAQS have not yet been made.
  Nonattainment for the 2008 Ozone NAAQS would be based on three years
  of air quality data from later years. Also, the county numbers in this
  row include only the counties with monitors violating the 2008 Ozone
  NAAQS. The numbers in this table may be an underestimate of the number
  of counties and populations that will eventually be included in areas
  with multiple counties designated nonattainment.

(b) Projected Levels Without This Final Action
    States with 8-hour ozone nonattainment areas are required to take 
action to bring those areas into compliance in the future. Based on the 
final rule designating and classifying 8-hour ozone nonattainment areas 
for the 1997 standard (69 FR 23951, April 30, 2004), most 8-hour ozone 
nonattainment areas will be required to attain the ozone NAAQS in the 
2007 to 2013 time frame and then maintain the NAAQS thereafter. As 
noted, EPA is reconsidering the 2008 ozone NAAQS. If EPA promulgates 
different ozone NAAQS in 2011 as a result of the reconsideration, these 
standards would replace the 2008 ozone NAAQS and there would no longer 
be a requirement to designate areas for the 2008 NAAQS. Attainment 
dates for any 2011 ozone NAAQS would range from 3 to 20 years from 
designation, depending on the area's classification.
    EPA has already adopted many emission control programs that are 
expected to reduce ambient ozone levels and assist in reducing the 
number of areas that fail to achieve the ozone NAAQS. Even so, our air 
quality modeling projects that in 2030, with all current controls but 
excluding the impacts of the heavy-duty standards, up to 10 counties 
with a population of over 30 million may not attain the 2008 ozone 
standard of 0.075 ppm (75 ppb). These numbers do not account for those

[[Page 57313]]

areas that are close to (e.g., within 10 percent of) the 2008 ozone 
standard. These areas, although not violating the standards, will also 
be impacted by changes in ozone as they work to ensure long-term 
maintenance of the ozone NAAQS.
(c) Projected Levels With This Final Action
    Our modeling indicates ozone design value concentrations will 
decrease in many areas of the country due to this action. The decreases 
in ozone design values are likely due to projected tailpipe reductions 
in NOX and projected upstream emissions decreases in 
NOX and VOCs from reduced gasoline production. The majority 
of the ozone design value decreases are less than 1 ppb. The maximum 
projected decrease in an 8-hour ozone design value is 1.57 ppb in 
Jefferson County, Tennessee. On a population-weighted basis, the 
average modeled 8-hour ozone design values are projected to decrease by 
0.39 ppb in 2030 and the design values for those counties that are 
projected to be above the 2008 ozone standard in 2030 will see 
population-weighted decreases of 0.16 ppb due to the heavy-duty 
standards.
(2) Particulate Matter
(a) Current Levels
    PM2.5 concentrations exceeding the level of the 
PM2.5 NAAQS occur in many parts of the country. In 2005, EPA 
designated 39 nonattainment areas for the 1997 PM2.5 NAAQS 
(70 FR 943, January 5, 2005). These areas are composed of 208 full or 
partial counties with a total population exceeding 88 million. The 1997 
PM2.5 NAAQS was revised in 2006 and the 2006 24-hour 
PM2.5 NAAQS became effective on December 18, 2006. On 
October 8, 2009, the EPA issued final nonattainment area designations 
for the 2006 24-hour PM2.5 NAAQS (74 FR 58688, November 13, 
2009). These designations include 32 areas composed of 121 full or 
partial counties with a population of over 70 million. In total, there 
are 54 PM2.5 nonattainment areas composed of 243 counties 
with a population of almost 102 million people.
(b) Projected Levels Without This Final Action
    States with PM2.5 nonattainment areas are required to 
take action to bring those areas into compliance in the future. Areas 
designated as not attaining the 1997 PM2.5 NAAQS will need 
to attain the 1997 standards in the 2010 to 2015 time frame, and then 
maintain them thereafter. The 2006 24-hour PM2.5 
nonattainment areas will be required to attain the 2006 24-hour 
PM2.5 NAAQS in the 2014 to 2019 time frame and then be 
required to maintain the 2006 24-hour PM2.5 NAAQS 
thereafter. The heavy-duty standards finalized in this action become 
effective in 2012 and therefore may be useful to states in attaining or 
maintaining the PM2.5 NAAQS.
    EPA has already adopted many emission control programs that are 
expected to reduce ambient PM2.5 levels and which will 
assist in reducing the number of areas that fail to achieve the 
PM2.5 NAAQS. Even so, our air quality modeling projects that 
in 2030, with all current controls but excluding the impacts of the 
heavy-duty standards adopted here, at least 4 counties with a 
population of almost 7 million may not attain the 1997 annual 
PM2.5 standard of 15 [micro]g/m\3\ and 22 counties with a 
population of over 33 million may not attain the 2006 24-hour 
PM2.5 standard of 35 [micro]g/m\3\. These numbers do not 
account for those areas that are close to (e.g., within 10 percent of) 
the PM2.5 standards. These areas, although not violating the 
standards, will also benefit from any reductions in PM2.5 
ensuring long-term maintenance of the PM2.5 NAAQS.
(c) Projected Levels With This Final Action
    Air quality modeling performed for this final action shows that in 
2030 the majority of the modeled counties will see decreases of less 
than 0.01 [micro]g/m\3\ in their annual PM2.5 design values. 
The decreases in annual PM2.5 design values that we see in 
some counties are likely due to emission reductions related to lower 
fuel production at existing oil refineries and/or reductions in 
PM2.5 precursor emissions (NOX, SOX, 
and VOCs) due to improvements in road load. The maximum projected 
decrease in an annual PM2.5 design value is 0.03 [micro]g/
m\3\ in Allen County, Indiana and Canyon County, Idaho. On a 
population-weighted basis, the average modeled 2030 annual 
PM2.5 design value is projected to decrease by 0.01 
[micro]g/m\3\ due to this final action.
    In addition to looking at annual PM2.5 design values, we 
also modeled the impact of the standards on 24-hour PM2.5 
design values. Air quality modeling performed for this final action 
shows that in 2030 the majority of the modeled counties will see 
changes of between -0.05 [micro]g/m\3\ and 0 [micro]g/m\3\ in their 24-
hour PM2.5 design values. The decreases in annual 
PM2.5 design values that we see in some counties are likely 
due to emission reductions related to lower fuel production at existing 
oil refineries and/or reductions in PM2.5 precursor 
emissions (NOX, SOX, and VOCs) due to 
improvements in road load. The maximum projected decrease in a 24-hour 
PM2.5 design value is 0.27 [micro]g/m\3\ in Canyon County, 
ID. There are also some counties that are projected to see increases of 
less than 0.1 [micro]g/m\3\ in their 24-hour PM2.5 design 
values. These small increases in 24-hour PM2.5 design values 
are likely related to downstream emission increases from APUs. On a 
population-weighted basis, the average modeled 2030 24-hour 
PM2.5 design value is projected to decrease by 0.03 
[micro]g/m\3\ due to this final action. Those counties that are 
projected to be above the 24-hour PM2.5 standard in 2030 
will see slightly smaller population-weighted decreases of 0.01 
[micro]g/m\3\ in their design values due to this final action.
(3) Air Toxics
(a) Current Levels
    The majority of Americans continue to be exposed to ambient 
concentrations of air toxics at levels which have the potential to 
cause adverse health effects.\467\ The levels of air toxics to which 
people are exposed vary depending on where people live and work and the 
kinds of activities in which they engage, as discussed in detail in 
U.S. EPA's most recent Mobile Source Air Toxics Rule.\468\ According to 
the National Air Toxic Assessment (NATA) for 2005,\469\ mobile sources 
were responsible for 43 percent of outdoor toxic emissions and over 50 
percent of the cancer risk and noncancer hazard. Benzene is the largest 
contributor to cancer risk of all 124 pollutants quantitatively 
assessed in the 2002 NATA and mobile sources were responsible for 59 
percent of benzene emissions in 2002. Over the years, EPA has 
implemented a number of mobile source and fuel controls resulting in 
VOC reductions, which also reduce benzene and other air toxic 
emissions.
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    \467\ U.S. Environmental Protection Agency (2007). Control of 
Hazardous Air Pollutants from Mobile Sources; Final Rule. 72 FR 
8434, February 26, 2007.
    \468\ U.S. Environmental Protection Agency (2007). Control of 
Hazardous Air Pollutants from Mobile Sources; Final Rule. 72 FR 
8434, February 26, 2007.
    \469\ U.S. EPA. (2011) 2005 National-Scale Air Toxics 
Assessment. http://www.epa.gov/ttn/atw/nata2005/. Docket EPA-HQ-OAR-
2010-0162.
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(b) Projected Levels
    Our modeling indicates that the heavy-duty standards have 
relatively little impact on national average ambient concentrations of 
the modeled air toxics. Additional detail on the air toxics results can 
be found in Section 8.2.3.3 of the RIA.

[[Page 57314]]

(4) Nitrogen and Sulfur Deposition
(a) Current Levels
    Over the past two decades, the EPA has undertaken numerous efforts 
to reduce nitrogen and sulfur deposition across the U.S. Analyses of 
long-term monitoring data for the U.S. show that deposition of both 
nitrogen and sulfur compounds has decreased over the last 17 years 
although many areas continue to be negatively impacted by deposition. 
Deposition of inorganic nitrogen and sulfur species routinely measured 
in the U.S. between 2005 and 2007 were as high as 9.6 kilograms of 
nitrogen per hectare (kg N/ha) averaged over three years and 20.8 
kilograms of sulfur per hectare (kg S/ha) averaged over three 
years.\470\ The data show that reductions were more substantial for 
sulfur compounds than for nitrogen compounds. These numbers are 
generated by the U.S. national monitoring network and they likely 
underestimate nitrogen deposition because neither ammonia nor organic 
nitrogen is measured. In the eastern U.S., where data are most 
abundant, total sulfur deposition decreased by about 44 percent between 
1990 and 2007, while total nitrogen deposition decreased by 25 percent 
over the same timeframe.\471\
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    \470\ U.S. EPA. U.S. EPA's Report on the Environment (Final 
Report). U.S. Environmental Protection Agency, Washington, DC, EPA/
600/R-07/045F (NTIS PB2008-112484). Docket EPA-HQ-OAR-2010-0162. 
Updated data available online at: http://cfpub.epa.gov/eroe/index.cfm?fuseaction=detail.viewInd&ch=46&subtop=341&lv=list.listByChapter&r=201744.
    \471\ U.S. EPA. U.S. EPA's 2008 Report on the Environment (Final 
Report). U.S. Environmental Protection Agency, Washington, DC, EPA/
600/R-07/045F (NTIS PB2008-112484). Docket EPA-HQ-OAR-2010-0162. 
Updated data available online at: http://cfpub.epa.gov/eroe/index.cfm?fuseaction=detail.viewInd&ch=46&subtop=341&lv=list.listByChapter&r=201744.
---------------------------------------------------------------------------

(b) Projected Levels
    Our air quality modeling projects decreases in nitrogen deposition, 
especially in the Midwest, as a result of the heavy-duty standards 
required by this final action. The heavy-duty standards will result in 
annual percent decreases of 0.5 percent to more than 2 percent in some 
cities in the Midwest, Phoenix, Albuquerque, and some areas in Texas. 
The remainder of the country will see only minimal changes in nitrogen 
deposition, ranging from decreases of less than 0.5 percent to 
increases of less than 0.5 percent. For a map of 2030 nitrogen 
deposition impacts and additional information on these impacts, see 
Section 8.2.3.4 of the RIA. The impacts of the heavy-duty standards on 
sulfur deposition are minimal, ranging from decreases of up to 0.5 
percent to increases of up to 0.5 percent.
(5) Visibility
(a) Current Levels
    As mentioned in Section VII.D(1)(a), millions of people live in 
nonattainment areas for the PM2.5 NAAQS. These populations, 
as well as large numbers of individuals who travel to these areas, are 
likely to experience visibility impairment. In addition, while 
visibility trends have improved in mandatory class I federal areas, the 
most recent data show that these areas continue to suffer from 
visibility impairment. In summary, visibility impairment is experienced 
throughout the U.S., in multi-state regions, urban areas, and remote 
mandatory class I federal areas.
(b) Projected Levels
    Air quality modeling conducted for this final action was used to 
project visibility conditions in 138 mandatory class I federal areas 
across the U.S. in 2030. The results show that all the modeled areas 
will continue to have annual average deciview levels above background 
in 2030.\472\ The results also indicate that the majority of the 
modeled mandatory class I federal areas will see very little change in 
their visibility, but some mandatory class I federal areas will see 
improvements in visibility due to the heavy-duty standards and a few 
mandatory class I federal areas will see visibility decreases. The 
average visibility at all modeled mandatory class I federal areas on 
the 20 percent worst days is projected to improve by 0.01 deciviews, or 
0.06 percent, in 2030. Section 8.2.3.5 of the RIA contains more detail 
on the visibility portion of the air quality modeling.
---------------------------------------------------------------------------

    \472\ The level of visibility impairment in an area is based on 
the light-extinction coefficient and a unitless visibility index, 
called a ``deciview,'' which is used in the valuation of visibility. 
The deciview metric provides a scale for perceived visual changes 
over the entire range of conditions, from clear to hazy. Under many 
scenic conditions, the average person can generally perceive a 
change of one deciview. The higher the deciview value, the worse the 
visibility. Thus, an improvement in visibility is a decrease in 
deciview value.
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VIII. What are the agencies' estimated cost, economic, and other 
impacts of the final program?

    In this section, we present the costs and impacts of the final HD 
National Program. It is important to note that NHTSA's final fuel 
consumption standards and EPA's final GHG emissions standards will both 
be in effect, and each will lead to average fuel efficiency increases 
and GHG emission reductions. The two agencies' final standards comprise 
the HD National Program.
    The net benefits of the final HD National Program consist of the 
effects of the program on:

 The vehicle program costs (costs of complying with the vehicle 
CO2 standards),
 Fuel savings associated with reduced fuel usage resulting from 
the program,
 Reductions in greenhouse gas emissions,
 The reductions in other (non-GHG) pollutants,
 Costs associated with increases in noise, congestion, and 
accidents resulting from increased vehicle use,
 Improvements in U.S. energy security impacts,
 Benefits associated with increased vehicle use due to the 
``rebound'' effect.

    We also present the cost-effectiveness of the standards, or the 
cost per ton of emissions reduced. Where possible, we identify the 
uncertain aspects of these economic impacts and attempt to quantify 
them when and if possible (e.g., sensitivity ranges associated with 
quantified and monetized GHG impacts; probabilistic uncertainty 
associated with non-GHG health benefits). For some impacts, however, 
there is a lack of adequate information to inform a probabilistic 
assessment of uncertainty. EPA continues to work toward developing a 
comprehensive strategy for characterizing the aggregate impact of 
uncertainty in key elements of its analyses and we will continue to 
work to refine these uncertainty analyses in the future as time and 
resources permit.
    The program may have other effects that are not included here. The 
agencies sought comment on whether any costs or benefits were omitted 
from this analysis, so that they could be explicitly recognized in the 
final rules. In particular, as discussed in Section III and in Chapter 
2 of the RIA, the technology cost estimates developed here take into 
account the costs to hold other vehicle attributes, such as size and 
performance, constant. In addition, the analysis assumes that the full 
technology costs are passed along to vehicle buyers. With these 
assumptions, because welfare losses are monetary estimates of how much 
buyers would have to be compensated to be made as well off as in the 
absence of the change,\473\ the price increase measures

[[Page 57315]]

the loss to the buyer.\474\ Assuming that the full technology cost gets 
passed along to the buyer as an increase in price, the technology cost 
thus measures the welfare loss to the buyer. Increasing fuel efficiency 
would have to lead to other changes in the vehicles that buyers find 
undesirable for there to be additional losses not included in the 
technology costs.
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    \473\ This approach describes the economic concept of 
compensating variation, a payment of money after a change that would 
make a consumer as well off after the change as before it. A related 
concept, equivalent variation, estimates the income change that 
would be an alternative to the change taking place. The difference 
between them is whether the consumer's point of reference is her 
welfare before the change (compensating variation) or after the 
change (equivalent variation). In practice, these two measures are 
typically very close together.
    \474\ Indeed, it is likely to be an overestimate of the loss to 
the buyer, because the buyer has choices other than buying the same 
vehicle with a higher price; she could choose a different vehicle, 
or decide not to buy a new vehicle. The buyer would choose one of 
those options only if the alternative involves less loss than paying 
the higher price. Thus, the increase in price that the buyer faces 
would be the upper bound of loss of consumer welfare, unless there 
are other changes to the vehicle due to the fuel economy 
improvements that make the vehicle less desirable to buyers.
---------------------------------------------------------------------------

    The agencies sought comments, including supporting data and 
quantitative analyses, of any additional impacts of the final standards 
on vehicle attributes and performance, and other potential aspects that 
could positively or negatively affect the welfare implications of this 
final rulemaking, not addressed in this analysis.
    The comments received by the agencies did not provide any clear 
insights into this question. Some comments noted the diversity of the 
trucking industry and expressed a request that the program continue the 
great variety of options for the industry, because of the variation in 
needs for different customers. Additional comments noted that the 
separate engine and vehicle programs support the maintenance of variety 
and current market structure. Though a few commenters raised concerns, 
no information was offered to indicate that choice will in fact be 
limited by the program, or that other vehicle attributes are adversely 
affected.
    The total monetized benefits (excluding fuel savings) under the 
program are projected to be $4.3 to $11.1 billion in 2030, depending on 
the value used for the social cost of carbon. These benefits are 
summarized below in Table 0-31. The costs of the program in 2030, 
presented in Table 0-29 are estimated to be approximately $2.2 billion 
for new engine and truck technology. The program is also estimated to 
provide $20.6 billion in savings realized by trucking operations 
through fewer fuel expenditures (calculated using pre-tax fuel prices), 
as shown in Table 0-30. The present value of the total monetized 
benefits (excluding fuel savings) under the program is expected to 
range from $48.7 billion to $180.1 billion with a 3 percent discount 
rate; with a 7 percent discount rate, the total monetized benefits are 
expected to range from $24.3 billion to $155.7 billion. These values, 
summarized in Table 0-31, depend on the value used for the social cost 
of carbon. The present value of costs of the program for new engine and 
truck technology, in Table 0-32, are expected to be $47.4 billion using 
a 3 percent discount rate, and $24.7 billion with a 7 percent discount 
rate. The present value of fuel savings (calculated using pre-tax fuel 
prices) is estimated at $375.3 billion with a 3 percent discount rate, 
and $166.5 billion with a 7 percent discount rate, as shown in Table 0-
32. Total net present benefits (in Table 0-32) are thus expected to 
range from $376.6 billion to $508 billion with a 3 percent discount 
rate, and $166.1 billion to $297.5 billion with a 7 percent discount 
rate.
    The estimates developed here are measured against a baseline fuel 
efficiency associated with MY 2010 vehicles. The agencies also 
considered an alternate baseline associated with AEO 2011 projections, 
which is further discussed in Section IX. All calculations presented in 
Section VIII use the constant 2010 vehicle baseline. The extent to 
which fuel efficiency improvements may have occurred in the absence of 
the rules affects the net benefits associated with the program. If 
trucks were to install technologies to achieve the fuel savings and 
reduced GHG emissions in the absence of this program, then both the 
costs and benefits of these fuel savings could be attributed to market 
forces, not the rules. As a baseline for estimates of the extent of 
fuel-saving technologies that might have been adopted in the absence of 
the program, the proposal used the level of these technologies in MY 
2010 vehicles. We sought comment on whether the agencies should use an 
alternative baseline based on data provided by commenters to estimate 
the degree to which the technologies discussed in the proposal would 
have been adopted in the absence of these rules. No comments were 
received on this issue. One comment cites the EPA draft RIA as noting a 
historic 1 percent per year improvement in fuel efficiency, and argues 
that the rules are therefore not needed; the actual figure in the draft 
RIA, however, was a 0.09 percent per year improvement.
    EPA has undertaken an analysis of the economy-wide impacts of the 
final heavy-duty truck fuel efficiency and GHG standards as an 
exploratory exercise that EPA believes could provide additional 
insights into the potential impacts of the program.\475\ These results 
were not a factor regarding the appropriateness of the final standards. 
It is important to note that the results of this modeling exercise are 
dependent on the assumptions associated with how manufacturers would 
make fuel efficiency improvements and how trucking operations would 
respond to increases in higher vehicle costs and improved vehicle fuel 
efficiency as a result of the final program.
---------------------------------------------------------------------------

    \475\ See Memorandum to Docket, ``Economy-Wide Impacts of Heavy-
Duty Truck Greenhouse Gas Emissions and Fuel Efficiency Standards'', 
May 20, 2011. Docket EPA-HQ-OAR-2010-0162.
---------------------------------------------------------------------------

    Further information on these and other aspects of the economic 
impacts of our rules are summarized in the following sections and are 
presented in more detail in the RIA for this final rulemaking.

A. Conceptual Framework for Evaluating Impacts

    This regulation is motivated primarily by the goals of reducing 
emissions of greenhouse gases and promoting U.S. energy security by 
reducing consumption and imports of petroleum-based fuels. These 
motivations involve classic externalities, meaning that private 
decisions do not incorporate all of the costs associated with these 
problems; these costs are not borne completely by the households or 
businesses whose actions are responsible for them. In the absence of 
some mechanism to ``internalize'' these costs--that is, to transfer 
their burden to individuals or firms whose decisions impose them--
individuals and firms will consume more petroleum-based fuels than is 
socially optimal. Externalities are a classic motivation for government 
intervention in markets. These externalities, as well as effects due to 
changes in emissions of other pollutants and other impacts, are 
discussed in Sections VIII.H--VIII.K.
    In some cases, these classic externalities are by themselves enough 
to justify the costs of imposing fuel efficiency standards. For some 
discount rates and some projected social costs of carbon, however, the 
reductions in these external costs are less than the costs of new fuel 
saving technologies needed to meet the standards. (See Tables 9-24 and 
9-25 in the RIA.) Nevertheless, this regulation reduces trucking 
companies' fuel costs; according to our estimates, these savings in 
fuel costs are by themselves sufficient to pay for the

[[Page 57316]]

technologies over periods of time considerably shorter than vehicles' 
expected lifetimes under the assumptions used for this analysis (e.g., 
AEO 2011 projected fuel prices). If these estimates are correct, then 
the entire value of the reductions in external costs represents 
additional net benefits of the program, beyond those resulting from the 
fact that the value of fuel savings exceeds the costs of technologies 
necessary to achieve them.
    It is often asserted that there are cost-effective fuel-saving 
technologies that markets do not take advantage of. This is commonly 
known as the ``energy gap'' or ``energy paradox.'' Standard economic 
theory suggests that in normally functioning competitive markets, 
interactions between vehicle buyers and producers would lead producers 
to incorporate all cost-effective technology into the vehicles that 
they offer, without government intervention. Unlike in the light-duty 
vehicle market, the vast majority of vehicles in the medium- and heavy-
duty truck market are purchased and operated by businesses with narrow 
profit margins, and for which fuel costs represent a substantial 
operating expense.
    Even in the presence of uncertainty and imperfect information--
conditions that hold to some degree in every market--we generally 
expect firms to attempt to minimize their costs in an effort to survive 
in a competitive marketplace, and therefore to make decisions that are 
in the best interest of the company and its owners and/or shareholders. 
In this case, the benefits of the rules would be due exclusively to 
reducing the economic costs of externalities resulting from fuel 
production and consumption. However, as discussed below in Section 
VIII.E, the agencies have estimated that the application of fuel-saving 
technologies in response to the final standards would, on average, 
yield significant private returns to truck owners (see Tables VIII-9 
through VIII-11, below). The agencies have also estimated that the 
application of these technologies would be significantly lower in the 
absence of the final standards (i.e., under the ``no action'' 
regulatory alternative), meaning that truck buyers and operators ignore 
opportunities to make investments in higher fuel efficiency that appear 
to offer significant cost savings.
    As discussed in the NPRM, there are several possible explanations 
in the economics literature for why trucking companies do not adopt 
technologies that would be expected to increase their profits: there 
could be a classic market failure in the trucking industry--market 
power, externalities, or asymmetric or incomplete (i.e., missing 
market) information; there could be institutional or behavioral 
rigidities in the industry (union rules, standard operating procedures, 
statutory requirements, loss aversion, etc.), whereby participants 
collectively do not minimize costs; or the engineering estimates of 
fuel savings and costs for these technologies might overstate their 
benefits or understate their costs in real-world applications. See 75 
FR at 74303-307.
    To try to understand why trucking companies have not adopted these 
seemingly cost-effective fuel-saving technologies, the agencies 
surveyed published literature about the energy paradox, and held 
discussions with numerous truck market participants. The proposal 
discussed five categories of possible explanations derived from these 
sources. Collectively, these five hypotheses may explain the apparent 
inconsistency between the engineering analysis, which finds a number of 
cost-effective methods of improving fuel efficiency, and the 
observation that many of these technologies are not widely adopted.
    These hypotheses include imperfect information in the original and 
resale markets, split incentives, uncertainty about future fuel prices, 
and adjustment and transactions costs. As the discussion indicated, 
some of these explanations suggest failures in the private market for 
fuel-saving technology in addition to the externalities caused by 
producing and consuming fuel that are the primary motivation for the 
rules. Other explanations suggest market-based behaviors that may imply 
additional costs of regulating truck fuel efficiency that are not 
accounted for in this analysis. As noted above, an additional 
explanation--adverse effects on other vehicle attributes--did not 
elicit supporting information in the public comments. Anecdotal 
evidence from various segments of the trucking industry suggests that 
many of the hypotheses discussed here may play a role in explaining the 
puzzle of why truck purchasers appear to under-invest in fuel 
efficiency, although different explanations may apply to different 
segments, or even different companies. The published literature does 
not appear to include empirical analysis or data related to this 
question.
    The agencies invited comment on these explanations, and on any data 
or information that could be used to investigate the role of any or all 
of these five hypotheses in explaining this energy paradox as it 
applies specifically to trucks. Some comments expressed dissatisfaction 
about the explanations presented; they argued that these arguments were 
not sufficient to explain the phenomenon. These comments argued that 
the truck owners and operators are better judges of the appropriate 
amount of fuel efficiency than are government agencies; they choose not 
to invest because of warranted skepticism about these technologies. The 
agencies also requested comment and information regarding any other 
hypotheses that could explain the appearance that cost-effective fuel-
saving technologies have not been widely incorporated into trucks. The 
following discussion summarizes the fuller discussion provided in the 
NPRM and includes discussion of the comments received.
(1) Information Issues in the Original Sale Markets
    One potential hypothesis for why the trucking industry does not 
adopt what appear to be inexpensive fuel saving technologies is that 
there is inadequate or unreliable information available about the 
effectiveness of many fuel-saving technologies for new vehicles. If 
reliable information on the effectiveness of many new technologies is 
absent, truck buyers will understandably be reluctant to spend 
additional money to purchase vehicles equipped with unproven 
technologies.
    This lack of information can manifest itself in multiple ways. For 
instance, the problem may arise purely because collecting reliable 
information on technologies is costly (also see Section VIII.A.5 below 
on transaction costs). Moreover, information has aspects of a public 
good, in that no single firm has the incentive to do the costly 
experimentation to determine whether or not particular technologies are 
cost-effective, while all firms benefit from the knowledge that would 
be gained from that experimentation. Similarly, if multiple firms must 
conduct the same tests to get the same information, costs could be 
reduced by some form of coordination of information gathering.
    While its effect on information is indirect, we expect the 
requirement for the use of new technologies included in this program 
will circumvent these information issues, resulting in their adoption, 
thus providing more readily available information about their benefits. 
The agencies appreciate, however, that the diversity of truck uses, 
driving situations, and driver behavior will lead to variation in the 
fuel savings that individual trucks or fleets experience from using 
specific technologies.

[[Page 57317]]

    One commenter noted that the SmartWay program targets combination 
tractor owners and thus should have the largest impact on that sector, 
rather than vocational or medium-duty trucks. However, the gap between 
actual investment in fuel efficiency and the agencies' estimates of 
optimal investment is largest for combination tractors. Some of the 
difference in magnitude is likely to be due to the higher vehicle miles 
traveled for combination tractors compared to medium-duty and 
vocational vehicles: more driving means more fuel savings. 
Additionally, not even a majority of semi-trucks are owned by 
participants in SmartWay; non-participants are unlikely to get all the 
benefits of participants. Other explanations, noted below, are also 
likely to play a role. This observation may also suggest some 
limitations of improved information provision as a means of addressing 
the ``efficiency gap.''
(2) Information Issues in the Resale Market
    In addition to issues in the new vehicle market, a second 
hypothesis for why trucking companies may not adopt what appear to be 
cost-effective technologies to save fuel is that the resale market may 
not adequately reward the addition of fuel-saving technology to 
vehicles to ensure their original purchase by new truck buyers. This 
inadequate payback for users beyond the original owner may contribute 
to the short payback period that new purchasers appear to expect.\476\ 
The agencies requested data and information on the extent to which 
costs of fuel saving equipment can be recovered in the resale truck 
market. No data were received. One reviewer disputed this theory on the 
basis that people are willing to pay more for better vehicles, new or 
used. It is not clear, however, whether buyers of used vehicles can 
tell which are the better vehicles.\477\
---------------------------------------------------------------------------

    \476\ See NAS 2010, Note 197, at p. 188.
    \477\ Akerlof, George A. ``The Market for `Lemons' Quality 
Uncertainty and the Market Mechanism,'' Quarterly Journal of 
Economics 84(3) (1970): 488-500 points out that asymmetric 
information--the seller has better information than the buyer--can 
potentially lead to complete failure of a market, even when both 
buyers and sellers would benefit from trade.
---------------------------------------------------------------------------

    Some of this unwillingness to pay for fuel-saving technology may be 
due to the extension of the information problems in the new vehicle 
market into resale markets. Buyers in the resale market have no more 
reason to trust information on fuel-saving technologies than buyers in 
the original market. Because actual fuel efficiency of trucks on the 
road depends on many factors, including geography and driving styles or 
habits, even objective sources such as logs of truck performance for 
used vehicles may not provide reliable information about the fuel 
efficiency that potential purchasers of used trucks will experience.
    A related possibility is that vehicles will be used for different 
purposes by their second owners than those for which they were 
originally designed, and the fuel-saving technology is therefore of 
less value.
    It is possible, though, that the fuel savings experienced by the 
secondary purchasers may not match those experienced by their original 
owners if the optimal secondary new use of the vehicle does not earn as 
many benefits from the technologies. One commenter asks whether the 
fuel-saving technology is unvalued because it is unproven or overrated. 
In that case, the premium for fuel-saving technology in the secondary 
market should accurately reflect its value to potential buyers 
participating in that market, even if it is lower than its value in the 
original market, and the market has not failed. Because the information 
necessary to optimize use in the secondary market may not be readily 
available or reliable, however, buyers in the resale market may have 
less ability than purchasers of new vehicles to identify and gain the 
advantages of new fuel-saving technologies, and may thus be even less 
likely to pay a premium for them.
    For these reasons, purchasers' willingness to pay for fuel 
efficiency technologies may be even lower in the resale market than in 
the original equipment market. Even when fuel-saving technologies will 
provide benefits in the resale markets, purchasers of used vehicles may 
not be willing to compensate their original owners fully for their 
remaining value. As a result, the purchasers of original equipment may 
expect the resale market to provide inadequate appropriate compensation 
for the new technologies, even when those technologies would reduce 
costs for the new buyers. This information issue may partially explain 
what appears to be the very short payback periods required for new 
technologies in the new vehicle market.
(3) Split Incentives in the Medium- and Heavy-Duty Truck Industry
    A third hypothesis explaining the energy paradox as applied to 
trucking involves split incentives. When markets work effectively, 
signals provided by transactions in one market are quickly transmitted 
to related markets and influence the decisions of buyers and sellers in 
those related markets. For instance, in a well-functioning market 
system, changes in the expected future price of fuel should be 
transmitted rapidly to those who purchase trucks, who will then 
reevaluate the amount of fuel-saving technology to purchase for new 
vehicles. If for some reason a truck purchaser will not be directly 
responsible for future fuel costs, or the individual who will be 
responsible for fuel costs does not decide which truck characteristics 
to purchase, then those price signals may not be transmitted 
effectively, and incentives can be described as ``split.''
    One place where such a split may occur is between the owners and 
operators of trucks. Because they are generally responsible for 
purchasing fuel, truck operators have strong incentives to economize on 
its use, and are thus likely to support the use of fuel-saving 
technology. However, the owners of trucks or trailers are often 
different from operators, and may be more concerned about their 
longevity or maintenance costs than about their fuel efficiency, when 
purchasing vehicles. As a result, capital investments by truck owners 
may be channeled into equipment that improves vehicles' durability or 
reduces their maintenance costs, rather than into fuel-saving 
technology. If operators can choose freely among the trucks they drive, 
competition among truck owners to employ operators would encourage 
owners to invest in fuel-saving technology. However, if truck owners 
have more ability to choose among operators, then market signals for 
improved fuel savings that would normally be transmitted to truck 
owners may be muted. Truck fleets that rent their vehicles may provide 
an example: renters may observe the cost of renting the truck, but not 
its fuel efficiency; if so, then the purchasers will aim for vehicles 
with lower costs, to lower the cost of the rental. It might be possible 
to test this theory by comparing the fuel efficiency of trucks by 
owner-operators with those that are leased by operators. The agencies 
have not had the data to conduct such a test.
    One commenter noted that there are always tradeoffs in an 
investment decision: a purchaser may prefer to invest in other vehicle 
attributes than fuel efficiency. In an efficient market, however, a 
purchaser should invest in fuel-saving technology as long as the 
increase in fuel-saving technology costs less than the expected fuel 
savings. This result should hold regardless of the level of investment 
in other attributes, unless there are constraints on a

[[Page 57318]]

purchaser's access to investment capital. The agencies believe that 
truck fleets do have an incentive to make investments in fuel 
efficiency, and that this assumption is reflected in the regulatory 
analysis. The agencies also believe, however, that sufficient evidence 
suggests that truck fleets are not availing themselves of all the 
opportunities for efficiency improvements.
    In addition, the NAS report notes that split incentives can arise 
between tractor and trailer operators.\478\ Trailers affect the fuel 
efficiency of shipping, but trailer owners do not face strong 
incentives to coordinate with truck owners. EPA and NHTSA are not 
regulating trailers in this action.
---------------------------------------------------------------------------

    \478\ See NAS 2010, Note 197, at p. 182.
---------------------------------------------------------------------------

    By itself, information provision may be inadequate to address the 
potential underinvestment in fuel efficiency resulting from such split 
incentives. In this setting, regulation may contribute to fuel savings 
that otherwise may be difficult to achieve.
(4) Uncertainty About Future Cost Savings
    Another hypothesis for the lack of adoption of seemingly fuel 
saving technologies may be uncertainty about future fuel prices or 
truck maintenance costs. When purchasers have less than perfect 
foresight about future operating expenses, they may implicitly discount 
future savings in those costs due to uncertainty about potential 
returns from investments that reduce future costs. In contrast, the 
immediate costs of the fuel-saving or maintenance-reducing technologies 
are certain and immediate, and thus not subject to discounting. In this 
situation, both the expected return on capital investments in higher 
fuel efficiency and potential variance about its expected rate may play 
a role in a firm's calculation of its payback period on such 
investments.
    In the context of energy efficiency investments for the home, 
Metcalf and Rosenthal (1995) and Metcalf and Hassett (1995) observe 
that households weigh known, up-front costs that are essentially 
irreversible against an unknown stream of future fuel savings.\479\ 
Notably, in this situation, requiring households to adopt technologies 
more quickly may make them worse off by imposing additional risk on 
them.
---------------------------------------------------------------------------

    \479\ Metcalf, G., and D. Rosenthal (1995). ``The `New' View of 
Investment Decisions and Public Policy Analysis: An Application to 
Green Lights and Cold Refrigerators,'' Journal of Policy Analysis 
and Management 14: 517-531. Hassett and Metcalf (1995). ``Energy Tax 
Credits and Residential Conservation Investment: Evidence from Panel 
Data'' Journal of Public Economics 57 (1995): 201-217. Metcalf, G., 
and K. Hassett (1999). ``Measuring the Energy Savings from Home 
Improvement Investments: Evidence from Monthly Billing Data.'' The 
Review of Economics and Statistics 81(3): 516-528.
---------------------------------------------------------------------------

    Greene et al (2009) also finds support for this explanation in the 
context of light-duty fuel economy decisions: a loss-averse consumer's 
expected net present value of increasing the fuel economy of a 
passenger car can be very close to zero, even if a risk-neutral 
expected value calculation shows that its buyer can expect significant 
net benefits from purchasing a more fuel-efficient car.\480\ Supporting 
this hypothesis is a finding by Dasgupta et al. (2007) that consumers 
are more likely to lease than buy a vehicle with higher maintenance 
costs because it provides them with the option to return it before 
those costs become too high.\481\ However, the agencies know of no 
studies that have estimated the impact of uncertainty on perceived 
future savings for medium- and heavy-duty vehicles.
---------------------------------------------------------------------------

    \480\ Greene, D., J. German, and M. Delucchi (2009). ``Fuel 
Economy: The Case for Market Failure'' in Reducing Climate Impacts 
in the Transportation Sector, Sperling, D., and J. Cannon, eds. 
Springer Science.
    \481\ Dasgupta, S., S. Siddarth, and J. Silva-Risso (2007). ``To 
Lease or to Buy? A Structural Model of a Consumer's Vehicle and 
Contract Choice Decisions.'' Journal of Marketing Research 44: 490-
502.
---------------------------------------------------------------------------

    Purchasers' uncertainty about future fuel prices implies that 
mandating improvements in fuel efficiency can reduce the expected 
utility associated with truck purchases. This is because adopting such 
regulation requires purchasers to assume a greater level of risk than 
they would in its absence, even if the future fuel savings predicted by 
a risk-neutral calculation actually materialize. One commenter 
expressed support for this argument. Thus the mere existence of 
uncertainty about future savings in fuel costs does not by itself 
assure that regulations requiring improved fuel efficiency will 
necessarily provide economic benefits for truck purchasers and 
operators. On the other hand, because risk aversion reduces expected 
returns for businesses, competitive pressures can reduce risk aversion: 
risk-neutral companies can make higher average profits over time. Thus, 
significant risk aversion is unlikely to survive competitive pressures.
(5) Adjustment and Transactions Costs
    Another hypothesis is that transactions costs of changing to new 
technologies (how easily drivers will adapt to the changes, e.g.) may 
slow or prevent their adoption. Because of the diversity in the 
trucking industry, truck owners and fleets may like to see how a new 
technology works in the field, when applied to their specific 
operations, before they adopt it. One commenter expressed support for 
this argument. If a conservative approach to new technologies leads 
truck buyers to adopt new technologies slowly, then successful new 
technologies are likely to be adopted over time without market 
intervention, but with potentially significant delays in achieving fuel 
saving, environment, and energy security benefits.
    In addition, there may be costs associated with training drivers to 
realize the potential fuel savings enabled by new technologies, or with 
accelerating fleet operators' scheduled fleet turnover and replacement 
to hasten their acquisition of vehicles equipped with new fuel-saving 
technologies. Here, again, there may be no market failure; requiring 
the widespread use of these technologies may impose adjustment and 
transactions costs not included in this analysis. As in the discussion 
of the role of risk, these adjustment and transactions costs are 
typically immediate and undiscounted, while their benefits are future 
and uncertain; risk or loss aversion may further discourage companies 
from adopting new technologies.
    To the extent that there may be transactions costs associated with 
the new technologies, then regulation gives all new truck purchasers a 
level playing field, because it will require all of them to adjust on 
approximately the same time schedule. If experience with the new 
technologies serves to reduce uncertainty and risk, the industry as a 
whole may become more accepting of new technologies. This could 
increase demand for future new technologies and induce additional 
benefits in the legacy fleet through complementary efforts such as 
SmartWay.
(6) Additional Hypotheses
    In the public comments, two additional ideas were raised for the 
lack of adoption of what appears to be cost-effective fuel-saving 
technology. The first suggestion is that tighter diesel emissions 
standards caused engine manufacturers to invest heavily (both 
financially and with personnel) in emissions reduction technologies, 
and hence, were unable to invest in fuel efficiency technologies. A 
second suggestion is that a truck may be a ``positional good''--that 
is, a good whose value depends on how it compares to the goods owned by 
others. If trucks confer status on their owners or operators, and if 
that status depends on easily observable characteristics,

[[Page 57319]]

then owners may invest disproportionately in status-granting 
characteristics rather than less visible characteristics, such as fuel 
efficiency. Because status depends on comparisons to others, an ``arms 
race'' may develop in which all parties spend additional money on 
visible characteristics but may not manage to make themselves better 
off. In this case, regulation may improve welfare: by increasing the 
requirements for non-positional fuel efficiency, regulation could 
reduce expenditures made purely for competition rather than actual 
increase in welfare. In a competitive business, cost reduction provides 
a major opportunity cost to investing in status rather than in fuel-
saving technology; thus, this argument may play less of a role in the 
heavy-duty market than in the consumer market for vehicles.
    Both these hypotheses leave open the question, though, why 
additional investments were not made in fuel efficiency if they would 
provide rapid payback. Truck purchasers should, in principle, be 
willing to buy additional fuel-saving technology as long as it is cost-
effective, regardless of other vehicle attributes. Limited access to 
capital, if it is a problem in this sector, might provide some reason 
for the ``crowding out'' of the purchase of fuel-saving technology. The 
agencies received no evidence indicating that constrained access to 
capital might explain the efficiency gap in this market.
(7) Summary
    On the one hand, commercial vehicle operators are under competitive 
pressure to reduce operating costs, and thus their purchasers would be 
expected to pursue and rapidly adopt cost-effective fuel-saving 
technologies. On the other hand, the short payback period required by 
buyers of new trucks is a symptom that suggests some combination of 
uncertainty about future cost savings, transactions costs, and 
imperfectly functioning markets. In addition, widespread use of 
tractor-trailer combinations introduces the possibility that owners of 
trailers may have weaker incentives than truck owners or operators to 
adopt fuel-saving technology for their trailers. The market for medium- 
and heavy-duty trucks may face these problems, both in the new vehicle 
market and in the resale market.
    Provision of information about fuel-saving technologies through 
voluntary programs such as SmartWay will assist in the adoption of new 
cost-saving technologies, but diffusion of new technologies can still 
be obstructed. Those who are willing to experiment with new 
technologies expect to find cost savings, but those may be difficult to 
prove. As noted above, because individual results of new technologies 
vary, new truck purchasers may find it difficult to identify or verify 
the effects of fuel-saving technologies. Those who are risk-averse are 
likely to avoid new technologies out of concerns over the possibility 
of inadequate returns on the investment, or with other adverse impacts. 
Competitive pressures in the freight transport industry can provide a 
strong incentive to reduce fuel consumption and improve environmental 
performance. However, not every driver or trucking fleet operating 
today has the requisite ability or interest to access the technical 
information, some of which is already provided by SmartWay, nor the 
resources necessary to evaluate this information within the context of 
his or her own freight operation.
    It is unclear, as discussed above, whether some or many of the 
technologies would be adopted in the absence of the program. To the 
extent that they would have been adopted, the costs and the benefits 
attributed to those technologies may not in fact be due to the program 
and may therefore be overstated. Both baselines used project 
substantially less adoption than the agencies consider to be cost-
effective. The agencies will continue to explore reasons for this slow 
adoption of cost-effective technologies.

B. Costs Associated With the Final Program

    In this section, the agencies present the estimated costs 
associated with the final program. The presentation here summarizes the 
costs associated with new technology expected to be added to meet the 
new GHG and fuel consumption standards. The analysis summarized here 
provides the estimate of incremental costs on a per truck basis and on 
an annual total basis.
    The presentation here summarizes the best estimate by EPA and NHTSA 
staff as to the technology mix expected to be employed for compliance. 
For details behind the cost estimates associated with individual 
technologies, the reader is directed to Section III of this preamble 
and to Chapter 2 of the RIA.
    With respect to the cost estimates presented here, the agencies 
note that, because these estimates relate to technologies which are in 
most cases already available, these cost estimates are technically 
robust.
(1) Costs per Truck
    For the heavy-duty pickup trucks and vans, the agencies have used a 
methodology consistent with that used for our recent light-duty joint 
rulemaking since most of the technologies expected for heavy-duty 
pickup trucks and vans is consistent with that expected for the larger 
light-duty trucks. The cost estimates presented in the recent light-
duty joint rulemaking were then scaled upward to account for the larger 
weight, towing capacity, and work demands of the trucks in these 
heavier classes. For details on that scaling process and the resultant 
costs for individual technologies, the reader is directed to Section 
III of this preamble and to Chapter 2 of the RIA. Note also that all 
cost estimates have been updated to 2009 dollars for this analysis 
while the heavy-duty GHG emissions and fuel efficiency proposal was 
presented in 2008 dollars and the light-duty rule was presented in 2007 
dollars.
    For the loose heavy-duty gasoline engines, we have generally used 
engine-related costs from the heavy-duty pickup truck and van estimates 
since the loose heavy-duty gasoline engines are essentially the same 
engines as those sold into the heavy-duty pickup truck and van market.
    For heavy-duty diesel engines, the agencies have estimated costs 
using a different methodology than that employed in the recent light-
duty joint rulemaking. In the light-duty 2012-2016 MY vehicle rule, the 
fixed costs were included in the hardware costs via an indirect cost 
multiplier. As such, the hardware costs presented in that analysis, and 
in the cost estimates for Class 2b and 3 trucks, included both the 
actual hardware and the associated fixed costs. For this analysis, some 
of the fixed costs are estimated separately for HD diesel engines and 
are presented separately from the hardware costs. For details, the 
reader is directed to Chapter 2 of the RIA. Importantly, both 
methodologies after the figures are totaled account for all the costs 
associated with the program. As noted above, all costs are presented in 
2009 dollars.
    The estimates of vehicle compliance costs cover the years leading 
up to--2012 and 2013--and including implementation of the program--2014 
through 2018. Also presented are costs for the years following 
implementation to shed light on the long term (2022 and later) cost 
impacts of the program. The year 2022 was chosen here consistent with 
the light-duty 2012-2016 MY vehicle rule. That year was considered long 
term in that analysis because the short-term and long-term markup 
factors described shortly below are applied in five year increments 
with the 2012 through 2016 implementation span and

[[Page 57320]]

the 2017 through 2021 span both representing the short-term. Since many 
of the costs used in this analysis are based on costs in the light-duty 
rule analysis, consistency with that analysis seems appropriate.
    Some of the individual technology cost estimates are presented in 
brief in Section III, and account for both the direct and indirect 
costs incurred in the manufacturing and dealer industries (for a 
complete presentation of technology costs, please refer to Chapter 2 of 
the RIA). To account for the indirect costs on Class 2b and 3 pickup 
trucks and vans, the agencies have applied an ICM factor to all of the 
direct costs to arrive at the estimated technology cost. The ICM factor 
used was 1.24 in the short-term (2014 through 2021) to account for 
differences in the levels of R&D, tooling, and other indirect costs 
that will be incurred. Once the program has been fully implemented, 
some of the indirect costs will no longer be attributable to these 
standards and, as such, a lower ICM factor is applied to direct costs 
in 2022 and later. The agencies have also applied ICM factors to Class 
4 through 8 trucks and to heavy-duty diesel engine technologies. Markup 
factors in these categories range from 1.15 to 1.30 in the short term 
(2014 through 2021) depending on the complexity of the given 
technology. We have modified the manner in which ICMs are applied in 
that they are no longer applied as a simple multiplicative factor on 
top of the direct manufacturing costs. Instead, we have broken out the 
warranty cost portion of the ICM and apply it in a multiplicative 
manner then add the non-warranty cost portion of the ICM to that. The 
latter portion, that for non-warranty costs, is determined for a given 
year and held constant rather than decreasing year-over-year. This new 
approach, which responds to criticisms from some that the 
multiplicative approach used in the past essentially double counts 
learning effects, is discussed in Section VIII.C and is detailed in 
chapter 2 of the RIA. Note that, for the HD diesel engines, the 
agencies have applied the ICMs to ensure that our estimates are 
conservative since we have estimated fixed costs separately for 
technologies applied to these categories--effectively making the use of 
markups a double counting of indirect costs. For the details on the 
background and the concept behind our use of ICMs to calculate indirect 
costs, please refer to the report that has been placed in the docket 
for this final action.\482\
---------------------------------------------------------------------------

    \482\ RTI International. Heavy-duty Truck Retail Price 
Equivalent and Indirect Cost Multipliers. July 2010.
---------------------------------------------------------------------------

    The agencies have also considered the impacts of manufacturer 
learning on the technology cost estimates by reflecting the phenomenon 
of volume-based learning curve cost reductions in our modeling using 
two algorithms depending on where in the learning cycle (i.e., on what 
portion of the learning curve) we consider a technology to be--
``steep'' portion of the curve for newer technologies and ``flat'' 
portion of the curve for mature technologies. The observed phenomenon 
in the economic literature which supports manufacturer learning cost 
reductions are based on reductions in costs as production volumes 
increase, and the economic literature suggests these cost reductions 
occur indefinitely, though the absolute magnitude of the cost 
reductions decrease as production volumes increase (with the highest 
absolute cost reduction occurring with the first doubling of 
production). The agencies use the terminology ``steep'' and ``flat'' 
portion of the curve to distinguish among newer technologies and more 
mature technologies, respectively, and how learning cost reductions are 
applied in cost analyses. The steep learning algorithm applies for the 
early, steep portion of the learning curve and is estimated to result 
in 20 percent lower costs after two full years of implementation (i.e., 
a 2016 MY cost would be 20 percent lower than the 2014 and 2015 model 
year costs for a new technology being implemented in 2014). The flat 
learning algorithm applies for the flatter portion of the learning 
curve and is estimated to result in 3 percent lower costs in each of 
the five years following first introduction of a mature technology 
added in response to this final action. Once two steep learning steps 
have occurred (for technologies having steep learning applied), flat 
learning would begin. For technologies to which flat learning is 
applied, learning would begin in year 2 at 3 percent per year for 5 
years. Beyond 5 years of flat learning at 3 percent per year, 5 years 
of flat learning at 2 percent per year, then 5 at 1 percent per year 
become effective.
    Learning impacts have been considered on most but not all of the 
technologies expected to be used because some of the expected 
technologies are already used rather widely in the industry and, 
presumably, learning impacts have already occurred. The agencies have 
applied the steep learning algorithm for only a handful of technologies 
considered to be new or emerging technologies such as energy recovery 
systems and thermal storage units which might one day be used on big 
trucks. For most technologies, the agencies have considered them to be 
more established and, hence, the agencies have applied the lower flat 
learning algorithm. For more discussion of the learning approach and 
the technologies to which each type of learning has been applied the 
reader is directed to chapter 2 of the RIA.
    The technology cost estimates discussed in Section III and detailed 
in Chapter 2 of the RIA are used to build up technology package cost 
estimates. For each engine and truck class, a single package for each 
was developed capable of complying with the final standards and the 
costs for each package was generated. The technology packages and 
package costs are discussed in more detail in Chapter 2 of the RIA. The 
compliance cost estimates take into account all credits and trading 
programs and include costs associated with air conditioning controls. 
Table VIII-1 presents the average incremental costs per truck for this 
final action. For HD pickup trucks and vans (Class 2b and 3), costs 
increase as the standards become more stringent in 2014 through 2018. 
Following 2018, costs then decrease going forward as learning effects 
result in decreased costs for individual technologies. By 2022, the 
long term ICMs take effect and costs decrease yet again. For vocational 
vehicles, cost trends are more difficult to discern as diesel engines 
begin adding technology in 2014, gasoline engines begin adding 
technology in 2016, and the trucks themselves begin adding technology 
in 2014. With learning effects the costs, in general, decrease each 
year except for the heavy-duty gasoline engine changes in 2016. Long 
term ICMs take effect in 2022 to provide more cost reductions.

[[Page 57321]]

For combination tractors, costs generally decrease each year due to 
learning effects with the exception of 2017 when the engines placed in 
sleeper cab tractors add turbo compounding. Following that, learning 
impacts result in cost reductions and the long term ICMs take effect in 
2022 for further cost reductions. By 2030 and later, cost-per-truck 
estimates remain constant for all classes. Regarding the long term ICMs 
taking effect in 2022, the agencies consider this the point at which 
some indirect costs decrease or are no longer considered attributable 
to the program (e.g., warranty costs go down). Costs per truck remain 
essentially constant thereafter.

                                     Table VIII-1--Estimated Cost per Truck
                                                 [2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                              HD Pickups &
                                                                  vans           Vocational        Combination
----------------------------------------------------------------------------------------------------------------
2014......................................................              $165              $329            $6,019
2015......................................................               215               320             5,871
2016......................................................               422               397             5,677
2017......................................................               631               387             6,413
2018......................................................             1,048               378             6,215
2020......................................................               985               366             6,004
2030......................................................               977               311             5,075
2040......................................................               977               305             5,075
2050......................................................               977               304             5,075
----------------------------------------------------------------------------------------------------------------

    These costs would, presumably, have some impact on new truck 
prices, although the agencies make no attempt at determining what the 
impact of increased costs would be on new truck prices. Nonetheless, on 
a percentage basis, the costs shown in Table VIII-1 for 2018 MY trucks 
(when all final requirements are fully implemented) would be roughly 
three percent for a typical HD pickup truck or van, less than one 
percent for a typical vocational vehicle, and roughly six percent for a 
typical combination truck/tractor using new truck prices of $40,000, 
$100,000 and $100,000, respectively. The costs would represent lower or 
higher percentages of new truck prices for new trucks with higher or 
lower prices, respectively. Given the wide range of new truck prices in 
these categories--a Class 4 vocational work truck might be $40,000 when 
new while a Class 8 refuse truck (i.e., a large vocational vehicle) 
might be as much as $200,000 when new--it is very difficult to reflect 
incremental costs as percentages of new truck prices for all trucks. 
What is presented here is the average cost (Table VIII-1) compared with 
typical new truck prices.
    As noted above, the fixed costs were estimated separately from the 
hardware costs for HD diesel engines that are placed in vocational 
vehicles and combination tractors. Those fixed costs are not included 
in Table VIII-1. The agencies have estimated the R&D costs at $6.8 
million per manufacturer per year for five years and the new test cell 
costs (to accommodate measurement of N2O emissions) at 
$63,087 per manufacturer. The test cell costs of N2O 
emissions measurement has been adjusted for the final rulemaking to 
reflect comments which stated approximately 75 percent of manufacturers 
would be required to update existing equipment while the other 25 
percent would require new equipment. These costs apply individually for 
LHD, MHD and HHD engines. Given the 14 manufacturers impacted by the 
final standards, 11 of which are estimated to sell both MHD and HHD 
engines and 3 of which are estimated to sell LHD engines, we have 
estimated a five year annual R&D cost of $170.3 million dollars (2 x 11 
x $6.8 million plus 3 x $7.75 million for each year 2012-2016) and a 
one-time test cell cost of $1.6 million dollars (2 x 11 x $63,087 plus 
3 x $63,087 in 2013). Estimating annual sales of HD diesel engines at 
roughly 600,000 units results in roughly $284 per engine per year for 
five years beginning in 2012 and ending in 2016. Again, these costs are 
not reflected in Table VIII-1, but are included in Table VIII-2 as 
``Other Engineering Costs.''
    The certification and compliance program costs, for all engine and 
truck types, are estimated at $6.5 million in the first year dropping 
to $2.3 million in each year thereafter and continuing indefinitely. 
These costs are detailed in the ``Draft Supporting Statement for 
Information Collection Request'' which is contained in the docket for 
this final action.\483\ The costs are higher in the first year due to 
capital expenses required to comply with new reporting burdens 
(facility upgrade costs are included in engineering costs as described 
above). Estimating annual sales of heavy-duty trucks at roughly 1.5 
million units would result in just over $4 per engine/truck in the 
first year and less than $2 per engine/truck per year thereafter. These 
costs are not reflected in Table VIII-1, but are included in Table 
VIII-2 below as ``Compliance Program'' costs.
---------------------------------------------------------------------------

    \483\ ``Draft Supporting Statement for Information Collection 
Request,'' Control of Greenhouse Gas Emissions from New Motor 
Vehicles: Proposed Heavy-Duty Engine and Vehicle Standards, EPA ICR 
Tracking Number 2394.01.
---------------------------------------------------------------------------

(2) Annual Costs of the HD National Program
    The costs presented here represent the incremental costs for newly 
added technology to comply with the program. Together with the 
projected increases in truck sales, the increases in per-truck average 
costs shown in Table VIII-1, above result in the total annual costs 
presented in Table VIII-2 below. Note that the costs presented in Table 
VIII-2 do not include the savings that will occur as a result of the 
improvements to fuel consumption. Those impacts are presented in 
Section 0. Note also that the costs presented here represent costs 
estimated to occur presuming that the final standards will continue in 
perpetuity. Any changes to the final standards would be considered as 
part of a future rulemaking. In other words, the final standards do not 
apply only to 2014-2018 model year trucks--they do, in fact, apply to 
all 2014 and later model year trucks. We present more detail regarding 
the 2014-2018 model year trucks in Sections VIII.L, where we summarize 
all monetized costs and benefits.

[[Page 57322]]

                                                 Table VIII-2--Annual Costs Associated With the Program
                                                                   [$Millions, 2009$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                               Other
                          Year                             HD Pickup and    Vocational      Combination     engineering     Compliance     Annual costs
                                                               vans          vehicles        tractors          costs       program costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
2012 \a\................................................              $0              $0              $0            $170              $0            $170
2013....................................................               0               0               0             172               0             172
2014....................................................             130             185           1,078             170             6.5           1,569
2015....................................................             157             170             922             170             2.3           1,422
2016....................................................             300             202             820             170             2.3           1,495
2017....................................................             447             198             951               0             2.3           1,598
2018....................................................             751             201           1,000               0             2.3           1,955
2020....................................................             754             202           1,001               0             2.3           1,959
2030....................................................             918             216           1,076               0             2.3           2,212
2040....................................................           1,024             281           1,372               0             2.3           2,679
2050....................................................           1,156             354           1,777               0             2.3           3,290
NPV, 3%.................................................          17,070           4,950          24,487             793              52          47,352
NPV, 7%.................................................           8,467           2,588          12,855             724              30          24,665
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
\a\ As explained in the text, ``Other Engineering Costs'' are estimated for years 2012 through 2016. These costs represent facility related costs and
  engineering development costs, much of which will have to begin prior to implementation of the new standards.

C. Indirect Cost Multipliers

(1) Markup Factors To Estimate Indirect Costs
    For all segments in this analysis, indirect costs are estimated by 
applying indirect cost multipliers (ICM) to direct cost estimates. ICMs 
were calculated by EPA as a basis for estimating the impact on indirect 
costs of individual vehicle technology changes that would result from 
regulatory actions. Separate ICMs were derived for low, medium, and 
high complexity technologies, thus enabling estimates of indirect costs 
that reflect the variation in research, overhead, and other indirect 
costs that can occur among different technologies. ICMs were also 
applied in the light-duty rule.
    Prior to developing the ICM methodology, EPA and NHTSA both applied 
a retail price equivalent (RPE) factor to estimate indirect costs. RPEs 
are estimated by dividing the total revenue of a manufacturer by the 
direct manufacturing costs. As such, it includes all forms of indirect 
costs for a manufacturer and assumes that the ratio applies equally for 
all technologies. ICMs are based on RPE estimates that are then 
modified to reflect only those elements of indirect costs that would be 
expected to change in response to a regulatory-induced technology 
change. For example, warranty costs would be reflected in both RPE and 
ICM estimates, while marketing costs might only be reflected in an RPE 
estimate but not an ICM estimate for a particular technology, if the 
new regulatory-induced technology change is not one expected to be 
marketed to consumers. Because ICMs calculated by EPA are for 
individual technologies, many of which are small in scale, they often 
reflect a subset of RPE costs; as a result, the RPE is typically higher 
than an ICM. This is not always the case, as ICM estimates for complex 
technologies may reflect higher than average indirect costs, with the 
resulting ICM larger than the averaged RPE for the industry.
    There is some level of uncertainty surrounding both the ICM and RPE 
markup factors. The ICM estimates used in this final action group all 
technologies into three broad categories and treat them as if 
individual technologies within each of the three categories (low, 
medium, and high complexity) will have the same ratio of indirect costs 
to direct costs. This simplification means it is likely that the direct 
cost for some technologies within a category will be higher and some 
lower than the estimate for the category in general. More importantly, 
the ICM estimates have not been validated through a direct accounting 
of actual indirect costs for individual technologies. Rather, the ICM 
estimates were developed using adjustment factors developed in two 
separate occasions: the first, a consensus process, was reported in the 
RTI report; the second, a modified Delphi method, was conducted 
separately and reported in an EPA memo.\484\ Both these panels were 
composed of EPA staff members with previous background in the 
automobile industry; the memberships of the two panels overlapped but 
were not the same.\485\ The panels evaluated each element of the 
industry's RPE estimates and estimated the degree to which those 
elements would be expected to change in proportion to changes in direct 
manufacturing costs. The method and estimates in the RTI report were 
peer reviewed by three industry experts and subsequently by reviewers 
for the International Journal of Production Economics.\486\ RPEs 
themselves are inherently difficult to estimate because the accounting 
statements of manufacturers do not neatly categorize all cost elements 
as either direct or indirect costs. Hence, each researcher developing 
an RPE estimate must apply a certain amount of judgment to the 
allocation of the costs. Moreover, RPEs for heavy- and medium-duty 
trucks and for engine manufacturers are not as well studied as they are 
for the light-duty automobile industry. Since empirical estimates of 
ICMs are ultimately derived from the same data used to measure RPEs, 
this affects both measures. However, the value of RPE has not been 
measured for specific technologies, or for groups of specific 
technologies. Thus applying a single average RPE to any given 
technology by definition overstates costs for very simple technologies, 
or understates them for advanced technologies.
---------------------------------------------------------------------------

    \484\ Helfand, Gloria, and Sherwood, Todd. ``Documentation of 
the Development of Indirect Cost Multipliers for Three Automotive 
Technologies.'' Memorandum, Assessment and Standards Division, 
Office of Transportation and Air Quality, U.S. Environmental 
Protection Agency, August 2009.
    \485\ NHTSA staff participated in the development of the process 
for the second, modified Delphi panel, and reviewed the results as 
they were developed, but did not serve on the panel.
    \486\ The results of the RTI report were published in Alex 
Rogozhin, Michael Gallaher, Gloria Helfand, and Walter McManus, 
``Using Indirect Cost Multipliers to Estimate the Total Cost of 
Adding New Technology in the Automobile Industry.'' International 
Journal of Production Economics 124 (2010): 360-368.
---------------------------------------------------------------------------

    In the proposal, we requested comment on our ICM factors and 
whether it was most appropriate to use ICMs or RPEs. We received no 
comment on the issue specifically, other than

[[Page 57323]]

basic comments that perhaps our ICM factors were low. In response, for 
this final action, we have adjusted our ICM factors such that they are 
slightly higher and, importantly, we have changed the way in which the 
factors are applied. The first change--increased ICM factors--has been 
done as a result of further thought among the EPA and NHTSA team that 
the ICM factors presented in the original RTI report \487\ for low and 
medium complexity technologies should no longer be used and that we 
should rely solely on the modified-Delphi values for these complexity 
levels.\488\ For that reason, we have eliminated the averaging of 
original RTI values with modified-Delphi values and instead are relying 
solely on the modified-Delphi values for low and medium complexity 
technologies. The second change--the way the factors are applied--
results in the warranty portion of the indirect costs being applied as 
a multiplicative factor (thereby decreasing going forward as direct 
manufacturing costs decrease due to learning), and the remainder of the 
indirect costs being applied as an additive factor (thereby remaining 
constant year-over-year and not being reduced due to learning). This 
second change has a comparatively large impact on the resultant 
technology costs and, we believe, more appropriately estimates costs 
over time. In addition to these changes, a secondary-level change was 
also made as part of this ICM recalculation to the light-duty ICMs and, 
therefore, to the ICMs used in this analysis for heavy-duty pickups and 
vans. That change was to revise upward the RPE level reported in the 
original RTI report from an original value of 1.46 to 1.5 to reflect 
the long term average RPE. The original RTI study was based on 2008 
data. However, an analysis of historical RPE data indicates that, 
although there is year to year variation, the average RPE has remained 
constant at roughly 1.5. ICMs will be applied to future year's data and 
therefore NHTSA and EPA staff believe that it would be appropriate to 
base ICMs on the historical average rather than a single year's result. 
Therefore, ICMs were adjusted to reflect this average level since the 
original value excluded net income. As a result, even the High 1 and 
High 2 ICMs used for heavy-duty pickups and vans have also changed. 
These changes to our ICMs and the methodology are described in greater 
detail in Chapter 2 of the final RIA.
---------------------------------------------------------------------------

    \487\ Rogozhin, Alex, Michael Gallaher, and Walter McManus. 
``Automobile Industry Retail Price Equivalent and Indirect Cost 
Multipliers.'' Report prepared for EPA by RTI International. EPA 
Report EPA-420-R-09-003, February 2009.
    \488\ Helfand, Gloria, and Sherwood, Todd. ``Documentation of 
the Development of Indirect Cost Multipliers for Three Automotive 
Technologies.'' Memorandum, Assessment and Standards Division, 
Office of Transportation and Air Quality, U.S. Environmental 
Protection Agency, August 2009.
---------------------------------------------------------------------------

D. Cost per Ton of Emissions Reductions

    The agencies have calculated the cost per ton of GHG reductions 
associated with this program on a CO2eq basis using the 
above costs and the emissions reductions described in Sections VI and 
VII. These values are presented in Table VIII-3 through Table VIII-5 
for HD pickups & vans, vocational vehicles and combination trucks/
tractors, respectively. The cost per metric ton of GHG emissions 
reductions has been calculated in the years 2020, 2030, 2040, and 2050 
using the annual vehicle compliance costs and emission reductions for 
each of those years. The value in 2050 represents the long-term cost 
per ton of the emissions reduced. The agencies have also calculated the 
cost per metric ton of GHG emission reductions including the savings 
associated with reduced fuel consumption (presented below in Section 
0). This latter calculation does not include the other benefits 
associated with this program such as those associated with energy 
security benefits as discussed later in Section VIII.I. By including 
the fuel savings, the cost per ton is generally less than $0 since the 
estimated value of fuel savings outweighs the program costs. The 
results for CO2eq costs per ton under the HD National 
Program across all regulated categories are shown in Table VIII-6.

               Table VIII-3--Annual Cost per Metric Ton of CO2eq Reduced--HD Pickup Trucks & Vans
                                                 [2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                   Cost per ton    Cost per ton
              Year                 Program cost    Fuel savings    CO2eq Reduced   (without fuel    (with fuel
                                                     (pre-tax)                       Savings)        savings)
----------------------------------------------------------------------------------------------------------------
2020............................            $800            $900               3            $240            -$30
2030............................             900           3,000              10              90            -200
2040............................           1,000           4,300              14              70            -240
2050............................           1,200           5,500              16              80            -270
----------------------------------------------------------------------------------------------------------------

                Table VIII-4--Annual Cost per Metric Ton of CO2eq Reduced--Vocational Vehicles a
                                                 [2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                   Cost per ton    Cost per ton
              Year                 Program cost    Fuel savings    CO2eq reduced   (without fuel    (with fuel
                                                     (pre-tax)                       savings)        savings)
----------------------------------------------------------------------------------------------------------------
2020............................            $200          $1,100               4             $50           -$210
2030............................             200           2,400               9              20            -250
2040............................             300           3,500              12              30            -270
2050............................             400           4,700              14              30            -310
----------------------------------------------------------------------------------------------------------------
Note:
\a\ The program costs, fuel savings, and CO2eq reductions of the engines installed in vocational vehicles are
  embedded in the vehicle standards and analysis.

[[Page 57324]]

               Table VIII-5--Annual Cost per Metric Ton of CO2eq Reduced--Combination Tractors \a\
                                                 [2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                   Cost per ton    Cost per ton
              Year                 Program cost    Fuel savings    CO2eq reduced   (without fuel    (with fuel
                                                     (pre-tax)                       savings)        savings)
----------------------------------------------------------------------------------------------------------------
2020............................          $1,000          $7,700              32             $30           -$210
2030............................           1,100          15,300              57              20            -250
2040............................           1,400          20,200              68              20            -280
2050............................           1,800          26,400              78              20            -320
----------------------------------------------------------------------------------------------------------------
Note:
\a\ The program costs, fuel savings, and CO2eq reductions of the engines installed in tractors are embedded in
  the tractor standards and analysis.

                        Table VIII-6--Annual Cost per Metric Ton of CO2eq Reduced--Final
                                                 [2009 dollars]
----------------------------------------------------------------------------------------------------------------
                                                                                   Cost per ton    Cost per ton
              Year                 Program cost    Fuel savings    CO2eq reduced   (without fuel    (with fuel
                                                     (pre-tax)                       savings)        savings)
----------------------------------------------------------------------------------------------------------------
2020............................          $2,000          $9,600              39             $50           -$190
2030............................           2,200          20,600              76              30            -240
2040............................           2,700          28,000              94              30            -270
2050............................           3,300          36,500             108              30            -310
----------------------------------------------------------------------------------------------------------------

E. Impacts of Reduction in Fuel Consumption

(1) What are the projected changes in fuel consumption?
    The new CO2 standards will result in significant 
improvements in the fuel efficiency of affected trucks. Drivers of 
those trucks will see corresponding savings associated with reduced 
fuel expenditures. The agencies have estimated the impacts on fuel 
consumption for the tailpipe CO2 standards. To do this, fuel 
consumption is calculated using both current CO2 emission 
levels and the new CO2 standards. The difference between 
these estimates represents the net savings from the CO2 
standards. Note that the total number of miles that vehicles are driven 
each year is different under the control case scenario than in the 
reference case due to the ``rebound effect,'' which is discussed in 
Section 0. EPA also notes that drivers who drive more than our average 
estimates for vehicle miles traveled (VMT) will experience more fuel 
savings; drivers who drive less than our average VMT estimates will 
experience less fuel savings.
    The expected impacts on fuel consumption are shown in Table VIII-7. 
The gallons shown in the tables reflect impacts from the new fuel 
consumption and CO2 standards and include increased 
consumption resulting from the rebound effect.

        Table VIII-7--Fuel Consumption Reductions of the Program
                            [Million gallons]
------------------------------------------------------------------------
                       Year                          Gasoline    Diesel
------------------------------------------------------------------------
2014..............................................          1        473
2015..............................................          3        846
2016..............................................         14      1,171
2017..............................................         31      1,643
2018..............................................         58      2,123
2020..............................................        114      2,986
2030..............................................        348      5,670
2040..............................................        453      7,046
2050..............................................        522      8,158
------------------------------------------------------------------------

(2) Potential Impacts on Global Fuel Use and Emissions
    EPA's quantified reductions in fuel consumption focus on the gains 
from reducing fuel used by heavy-duty vehicles within the United 
States. However, as discussed in Section VIII.I, EPA also recognizes 
that this regulation will lower the world price of oil (the 
``monopsony'' effect). Lowering oil prices could lead to an uptick in 
oil consumption globally, leading to a corresponding increase in GHG 
emissions in other countries. This global increase in emissions could 
slightly offset some of the emission reductions achieved domestically 
as a result of the regulation.
(3) What are the monetized fuel savings?
    Using the fuel consumption estimates presented in Table VIII-7, the 
agencies can calculate the monetized fuel savings associated with the 
final standards. To do this, reduced fuel consumption is multiplied in 
each year by the corresponding estimated average fuel price in that 
year, using the reference case taken from the AEO 2011. These estimates 
do not account for the significant uncertainty in future fuel prices; 
the monetized fuel savings will be understated if actual fuel prices 
are higher (or overstated if fuel prices are lower) than estimated. AEO 
is a standard reference used by NHTSA and EPA and many other government 
agencies to estimate the projected price of fuel. This has been done 
using both the pre-tax and post-tax fuel prices. Since the post-tax 
fuel prices are the prices paid at fuel pumps, the fuel savings 
calculated using these prices represent the savings consumers would 
see. The pre-tax fuel savings are those savings that society would see. 
Assuming no change in fuel tax rates, the difference between these two 
columns represents the reduction in fuel tax revenues that will be 
received by state and federal governments--about $200 million in 2014 
and $3 billion by 2050. These results are shown in Table VIII-8. Note 
that in Section VIII.L, the overall benefits and costs of the rules are 
presented and, for that reason, only the pre-tax fuel savings are 
presented there.

             Table VIII-8--Estimated Monetized Fuel Savings
                            [Millions, 2009$]
------------------------------------------------------------------------
                                                    Fuel         Fuel
                     Year                         savings      savings
                                                 (pre-tax)    (post-tax)
------------------------------------------------------------------------
2014..........................................       $1,200       $1,400

[[Page 57325]]

 
2015..........................................        2,200        2,600
2016..........................................        3,300        3,800
2017..........................................        4,800        5,500
2018..........................................        6,400        7,400
2020..........................................        9,600       10,900
2030..........................................       20,600       23,000
2040..........................................       28,000       30,600
2050..........................................       36,500       39,500
NPV, 3%.......................................      375,300      415,300
NPV, 7%.......................................      166,500      185,400
------------------------------------------------------------------------

    As shown in Table VIII-8, the agencies are projecting that truck 
consumers would realize very large fuel savings as a result of the 
final standards. As discussed further in the introductory paragraphs of 
Section VIII, it is a conundrum from an economic perspective that these 
large fuel savings have not been provided by manufacturers and 
purchased by consumers of these products. Unlike in the light-duty 
vehicle market, the vast majority of vehicles in the medium- and heavy-
duty truck market are purchased and operated by businesses; for them, 
fuel costs may represent substantial operating expenses. Even in the 
presence of uncertainty and imperfect information--conditions that hold 
to some degree in every market--we generally expect firms to be cost-
minimizing to survive in a competitive marketplace and to make 
decisions that are therefore in the best interest of the company and 
its owners and/or shareholders.
    A number of behavioral and market phenomena may lead to a 
disconnect between how businesses account for fuel savings in their 
decisions and the way in which we account for the full stream of fuel 
savings for these rules, including imperfect information in the 
original and resale markets, split incentives, uncertainty in future 
fuel prices, and adjustment or transactions costs (see Section VIII.A 
for a more detailed discussion). As discussed below in the context of 
rebound in Section VIII.E.5, the nature of the explanation for this gap 
may influence the actual magnitude of the fuel savings.
(4) Payback Period and Lifetime Savings on New Truck Purchases
    Another factor of interest is the payback period on the purchase of 
a new truck that complies with the new standards. In other words, how 
long would it take for the expected fuel savings to outweigh the 
increased cost of a new vehicle? For example, a new 2018 MY HD pickup 
truck and van is estimated to cost $1,048 more, a vocational vehicle 
$378 more, and a combination tractor $6,215 more (all values are on 
average, and relative to the reference case vehicle) due to the 
addition of new GHG reducing technology. This new technology will 
result in lower fuel consumption and, therefore, savings in fuel 
expenditures. But how many months or years would pass before the fuel 
savings exceed the upfront costs? Table VIII-9 shows the payback period 
analysis for HD pickup trucks and vans. The table shows fuel consumed 
under the reference case and fuel consumed by a 2018 model year truck 
under the program, inclusive of fuel consumed due to rebound miles. The 
decrease in fuel consumed under the program is then monetized by 
multiplying by the fuel price reported by AEO (reference case) for 2018 
and later. This value represents the fuel savings expected under the 
program for a HD pickup or van. These savings are then discounted each 
year since future savings are considered to be of less value than 
current savings. Shown next are estimated increased costs (costs do not 
necessarily reflect increased prices which may be higher or lower than 
costs) for the new truck (refer to Table VIII-1). The next columns of 
Table VIII-9 show the period required for the fuel savings to exceed 
the new truck costs. As seen in the table, in the second year of 
ownership, the discounted fuel savings (at both 3 and 7 percent 
discount rates) have begun to outweigh the increased cost of the truck. 
As shown in the table, the full life savings using 3 percent 
discounting would be $6,138 and at 7 percent discounting would be 
$4,459.

                                           Table VIII-9--Payback Period for a 2018 Model Year HD Pickup or Van
                                                                         [2009$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Reduced fuel use          Fuel savings \a\                      Cumulative savings
                                                                     (gallons) \b\      --------------------------  Increased  -------------------------
                      Year of ownership                       --------------------------                               cost
                                                                 Gasoline      Diesel    3% discount  7% discount               3% discount  7% discount
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................................................           67          122         $627         $616      -$1,048        -$421        -$433
2............................................................           67          122          617          583  ...........          196          151
3............................................................           66          120          600          546  ...........          796          696
4............................................................           64          117          570          499  ...........        1,366        1,196
5............................................................           62          113          544          458  ...........        1,910        1,654
6............................................................           59          108          507          411  ...........        2,417        2,065
7............................................................           56          102          474          370  ...........        2,890        2,435
Full Life....................................................          894        1,617        7,187        5,507       -1,048        6,138        4,459
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Fuel savings calculated using the AEO 2011 reference case fuel prices through 2035. Fuel prices beyond 2035 were extrapolated from an average growth
  rate for the years 2017 to 2035. Gasoline and diesel fuel prices have been weighted by gasoline and diesel fuel reductions estimated for all 2018 MY
  heavy-duty trucks during their lifetimes. These estimates assume no changes in fuel tax rates. If fuel taxes are increased to offset lost revenues,
  the post-tax savings will increase.
\b\ Gallons under the control case include gallons consumed during rebound driving.

    The story is somewhat different for vocational vehicles and 
combination tractors. These cases are shown in Table VIII-10 and Table 
VIII-11, respectively. Since these trucks travel more miles in a given 
year, their payback periods are shorter and are expected to occur 
within the second year of ownership under both the 3 and 7 percent 
discounting cases. As can be seen in Table VIII-10 and Table VIII-11, 
the lifetime fuel savings are estimated to be considerable with savings 
of $5,494 (3%) and $4,268 (7%) for the vocational vehicles and $72,875 
(3%) and $58,162 (7%) for the combination tractors.

[[Page 57326]]

                                         Table VIII-10--Payback Period for a 2018 Model Year Vocational Vehicle
                                                                         [2009$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Reduced fuel use          Fuel savings \a\                      Cumulative savings
                                                                     (gallons) \b\      --------------------------  Increased  -------------------------
                      Year of ownership                       --------------------------                               cost
                                                                 Gasoline      Diesel    3% discount  7% discount               3% discount  7% discount
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................................................           51          161         $702         $690        -$378         $325         $312
2............................................................           47          146          637          602  ...........          962          914
3............................................................           44          134          576          524  ...........        1,538        1,438
4............................................................           41          122          516          452  ...........        2,054        1,889
5............................................................           38          110          463          390  ...........        2,516        2,279
6............................................................           34           98          404          328  ...........        2,921        2,607
7............................................................           31           87          359          280  ...........        3,279        2,887
Full Life....................................................          550        1,458        5,872        4,646         -378        5,494        4,268
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Fuel savings calculated using the AEO 2011 reference case fuel prices through 2035. Fuel prices beyond 2035 were extrapolated from an average growth
  rate for the years 2017 to 2035. Gasoline and diesel fuel prices have been weighted by gasoline and diesel fuel reductions estimated for all 2018 MY
  heavy-duty trucks during their lifetimes. These estimates assume no changes in fuel tax rates. If fuel taxes are increased to offset lost revenues,
  the post-tax savings will increase.
\b\ Gallons under the control case include gallons consumed during rebound driving.

                                         Table VIII-11--Payback Period for a 2018 Model Year Combination Tractor
                                                                         [2009$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Reduced fuel use          Fuel savings \a\                      Cumulative savings
                                                                     (gallons) \b\      --------------------------  Increased  -------------------------
                      Year of ownership                       --------------------------                               cost
                                                                 Gasoline      Diesel    3% discount  7% discount               3% discount  7% discount
--------------------------------------------------------------------------------------------------------------------------------------------------------
1............................................................            0        3,223      $10,736      $10,539      -$6,215       $4,522       $4,324
2............................................................            0        2,897        9,619        9,089  ...........       14,141       13,413
3............................................................            0        2,619        8,564        7,790  ...........       22,705       21,203
4............................................................            0        2,359        7,532        6,595  ...........       30,237       27,797
5............................................................            0        2,096        6,626        5,585  ...........       36,863       33,382
6............................................................            0        1,842        5,684        4,611  ...........       42,546       37,993
7............................................................            0        1,617        4,951        3,867  ...........       47,497       41,860
Full Life....................................................            0       26,148       79,089       64,376       -6,215       72,875       58,162
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Fuel savings calculated using the AEO 2011 reference case fuel prices through 2035. Fuel prices beyond 2035 were extrapolated from an average growth
  rate for the years 2017 to 2035. Gasoline and diesel fuel prices have been weighted by gasoline and diesel fuel reductions estimated for all 2018 MY
  heavy-duty trucks during their lifetimes. These estimates assume no changes in fuel tax rates. If fuel taxes are increased to offset lost revenues,
  the post-tax savings will increase.
\b\ Gallons under the control case include gallons consumed during rebound driving.

    All of these payback analyses include fuel consumed during rebound 
VMT in the control case but not in the reference case, consistent with 
other parts of the analysis. Further, this analysis does not include 
other societal impacts such as reduced time spent refueling or noise, 
congestion and accidents since the focus is meant to be on those 
factors buyers think about most while considering a new truck purchase. 
Note also that operators that drive more miles per year than the 
average would realize greater fuel savings than estimated here, and 
those that drive fewer miles per year would realize lesser savings. The 
same holds true for operators that keep their vehicles longer (i.e., 
more years) than average in that they would realize greater lifetime 
fuel savings than operators that keep their vehicles for fewer years 
than average. Likewise, should fuel prices be higher than the AEO 2011 
reference case, operators will realize greater fuel savings than 
estimated here while they would realize lesser fuel savings were fuel 
prices to be lower than the AEO 2011 reference case.
(5) Rebound Effect
    The VMT rebound effect refers to the fraction of fuel savings 
expected to result from an increase in fuel efficiency that is offset 
by additional vehicle use. If truck shipping costs decrease as a result 
of lower fuel costs, an increase in truck VMT may occur. Unlike the 
light-duty rebound effect, the heavy-duty (HD) rebound effect has not 
been extensively studied. Because the factors influencing the HD 
rebound effect are generally different from those affecting the light-
duty rebound effect, much of the research on the light-duty rebound 
effect is not likely to apply to the HD sectors. One of the major 
differences between the HD rebound effect and the light-duty rebound 
effect is that HD vehicles are used primarily for business purposes. 
Since these businesses are profit driven, decision makers are highly 
likely to be aware of the costs and benefits of different shipping 
decisions, both in the near term and long term. Therefore, shippers are 
much more likely to take into account changes in the overall operating 
costs per mile when making shipping decisions that affect VMT.
    Another difference from the light-duty case is that, as discussed 
in the recent NAS Report,\489\ when calculating the percentage change 
in trucking costs to determine the rebound effect, all changes in the 
operating costs should be considered. The cost of labor and fuel 
generally constitute the top two shares of truck operating costs, 
depending on the price of petroleum,\490\ distance traveled, type of 
truck, and

[[Page 57327]]

commodity.\491\ Finally, the equipment costs associated with the 
purchase or lease of the truck is also a significant component of total 
operating costs. Even though vehicle costs are lump-sum purchases, they 
can be considered operating costs for trucking firms, and these costs 
are, in many cases, expected to be passed onto the final consumers of 
shipping services on a variable basis. This shipping cost increase 
could help temper the rebound effect relative to the case of light-duty 
vehicles, in which vehicle costs are not considered an operating cost 
by vehicle owners.
---------------------------------------------------------------------------

    \489\ See NAS Report, Note 197.
    \490\ American Transportation Research Institute, An Analysis of 
the Operational Costs of Trucking, December 2008 (Docket ID: EPA-HQ-
OAR-2010-0162-0007).
    \491\ Transport Canada, Operating Cost of Trucks, 2005. See 
http://www.tc.gc.ca/eng/policy/report-acg-operatingcost2005-2005-e-2-1727.htm, accessed on July 16, 2010 (Docket ID: EPA-HQ-OAR-2010-
0162-0006). See also ATRI, 2008.
---------------------------------------------------------------------------

    When calculating the net change in operating costs, both the 
increase in new vehicle costs and the decrease in fuel costs per mile 
should be taken into consideration. The higher the net cost savings, 
the higher the expected rebound effect. Conversely, if the upfront 
vehicle costs outweighed future cost savings and total costs increased, 
shipping costs would rise, which would likely result in a decrease in 
truck VMT. In theory, other changes such as maintenance costs and 
insurance rates would also be taken into account, although information 
on these potential cost changes is extremely limited. In the proposal, 
we invited comments on the most appropriate methodology for factoring 
new vehicle purchase or leasing costs into the per-mile operating 
costs. We also invited comment or data on how these regulations could 
affect maintenance, insurance, or other operating costs. We did not 
receive any comments on these assumptions.
    The following sections describe the factors affecting the rebound 
effect, different methodologies for estimating the rebound effect, and 
examples of different estimates of the rebound effect to date. 
According to the NAS study, it is ``not possible to provide a confident 
measure of the rebound effect,'' yet NAS concluded that a rebound 
effect likely exists and that ``estimates of fuel savings from 
regulatory standards will be somewhat misestimated if the rebound 
effect is not considered.'' While we believe the HD rebound effect 
needs to be studied in more detail, we have attempted to capture the 
potential impact of the rebound effect in our analysis. In the 
proposal, we solicited data on the rebound effect and input on the most 
appropriate estimates to use for the rebound effect. However, we did 
not receive any new data or substantive comments. Therefore, for this 
final action, we continue to use a rebound effect for vocational 
vehicles of 15 percent, a rebound effect for HD pickup trucks and vans 
of 10 percent, and a rebound effect for combination tractors of 5 
percent. These VMT impacts are reflected in the estimates of total GHG 
and other air pollution reductions presented in Chapter 5 of the RIA.
(a) Factors Affecting the Magnitude of the Rebound Effect
    The HD vehicle rebound effect is driven by the interaction of 
several different factors. In the short-run, decreasing the fuel cost 
per mile of driving could lead to a decrease in end product prices. 
Lower prices could stimulate additional demand for those products, 
which would then result in an increase in VMT. In the long run, 
shippers could reorganize their logistics and distribution networks to 
take advantage of lower truck shipping costs. For example, shippers may 
shift away from other modes of shipping such as rail, barge, or air. In 
addition, shippers may also choose to reduce the number of warehouses, 
reduce load rates, and make smaller, more frequent shipments, all of 
which could also lead to an increase in HD VMT. Finally, the benefits 
of the fuel savings could ripple through the economy, which could in 
turn increase overall demand for goods and services shipped by trucks, 
and therefore increase HD VMT.
    Conversely, if a fuel efficiency regulation leads to net increases 
in the cost of trucking because fuel savings do not fully offset the 
increase in upfront vehicle costs, then the price of trucking services 
could rise, spurring a decrease in HD VMT and a shift to alternative 
shipping modes. These effects would also ripple through the economy.
(b) Options for Quantifying the Rebound Effect
    As described in the previous section, the fuel efficiency rebound 
effect for HD vehicles has not been studied as extensively as the 
rebound effect for light-duty vehicles, and virtually no research has 
been conducted on the HD pickup truck and van rebound effect. In the 
proposal, we discussed four options for quantifying the rebound effect 
and requested comments. We did not receive any substantive comments on 
the described methodologies.
(i) Aggregate Estimates
    The aggregate approximation approach quantifies the overall change 
in truck VMT as a result of a percentage change in freight rates. It is 
important to note that most of the aggregate estimates measure the 
change in freight demanded (tons or ton-miles), rather than a change in 
fuel consumption or VMT. The change in tons or ton-miles is more 
accurately characterized as a freight elasticity. Therefore, it may not 
be entirely appropriate to interpret these freight elasticities as 
measures of the rebound effect, although these terms are sometimes used 
interchangeably in the literature.\492\ Given these caveats, freight 
elasticity estimates rely on estimates of aggregate price elasticity of 
demand for trucking services, given a percentage change in trucking 
prices, which is generally referred to as an ``own-price elasticity.'' 
Estimates of trucking own-price elasticities vary widely from positive 
1.72 to negative 7.92), and there is no general consensus on the most 
appropriate values to use, though a 2004 literature survey found 
aggregate elasticity estimates generally fall in the range of -0.5 to -
1.5.\493\ In other words, given an own-price elasticity of -1.5, a 10 
percent decrease in trucking prices leads to a 15 percent increase in 
truck shipping demand.
---------------------------------------------------------------------------

    \492\ Memo from Energy and Environmental Research Associates, 
LLC Regarding HDV Rebound Effect, dated June 8, 2011.
    \493\ Graham and Glaister, ``Road Traffic Demand Elasticity 
Estimates: A Review,'' Transport Reviews Volume 24, 3, pp. 261-274, 
2004 (Docket ID: EPA-HQ-OAR-2010-0162-0005).
---------------------------------------------------------------------------

    Another challenge of estimating the rebound effect using freight 
elasticities is that these values appear to vary substantially based on 
the demand elasticity measure (e.g., ton or ton-mile), the model 
specification (e.g., linear functional form or log linear), the length 
of the trip, and the type of cargo. In general, elasticity estimates of 
longer trips tend to be larger than elasticity estimates for shorter 
trips. In addition, elasticities tend to be larger for lower-value 
commodities compared to higher-value commodities. Although these 
factors explain some of the differences in estimates, much of the 
observed variation cannot be explained quantitatively. For example, a 
recent study that controlled for these variables only accounted for 
about half of the observed variation.\494\
---------------------------------------------------------------------------

    \494\ Li, Z., D.A. Hensher, and J.M. Rose, Identifying sources 
of systematic variation in direct price elasticities from revealed 
preference studies of inter-city freight demand. Transport Policy, 
2011.
---------------------------------------------------------------------------

    Another important variable influencing freight elasticity estimates 
is whether potential mode shifting is taken into account. Although the 
total demand for freight transport is generally determined by economic 
activity, there is often the choice of shipping freight on modes other 
than truck. This is because the United States has extensive rail, 
waterway and air transport networks in addition to an extensive highway 
network; these networks closely parallel

[[Page 57328]]

each other and are often both viable choices for freight transport for 
long-distance routes within the continent. If rates go down for one 
mode, there will be an increase in demand for that mode and some demand 
will be shifted from other modes. This ``cross-price elasticity'' is a 
measure of the percentage change in demand for shipping by another mode 
(e.g., rail) given a percentage change in the price of trucking. 
Aggregate estimates of cross-price elasticities also vary widely, and 
there is no general consensus on the most appropriate value to use for 
analytical purposes. The NAS report cites values ranging from 0.35 to 
0.59.\495\ Other reports provide significantly different cross-price 
elasticities, ranging from 0.1 \496\ to 2.0.\497\
---------------------------------------------------------------------------

    \495\ See 2010 NAS Report, Note 197. See also 2009 Cambridge 
Systematics, Inc., Draft Final Paper commissioned by the NAS in 
support of the medium-duty and heavy-duty report. Assessment of Fuel 
Economy Technologies for Medium and Heavy-duty Vehicles: 
Commissioned Paper on Indirect Costs and Alternative Approaches 
Docket ID: EPA-HQ-OAR-2010-0162-0009).
    \496\ Friedlaender, A. and Spady, R. (1980) A derived demand 
function for freight transportation, Review of Economics and 
Statistics, 62, pp. 432-441 (Docket ID: EPA-HQ-OAR-2010-0162-0004).
    \497\ Christidis and Leduc, ``Longer and Heavier Vehicles for 
freight transport,'' European Commission Joint Research Center's 
Institute for Prospective Technology Studies, 2009 (Docket ID: EPA-
HQ-OAR-2010-0162-0010).
---------------------------------------------------------------------------

    When considering intermodal shift, the most relevant kinds of 
shipments are those that are competitive between rail and truck modes. 
These trips generally include long-haul shipments greater than 500 
miles, which weigh between 50,000 and 80,000 pounds (the legal road 
limit in many states). Special kinds of cargo like coal and short-haul 
deliveries are of less interest because they are generally not 
economically transferable between truck and rail modes, and they would 
not be expected to shift modes except under an extreme price change. 
However, the total amount of freight that could potentially be subject 
to mode shifting has also not been studied extensively.
(ii) Sector-Specific Estimates
    Given the limited data available regarding the HD rebound effect, 
the aggregate approach greatly simplifies many of the assumptions 
associated with calculations of the rebound effect. In reality, 
however, responses to changes in fuel efficiency and new vehicle costs 
will vary significantly based on the commodities affected. A detailed, 
sector-specific approach would be expected to more accurately reflect 
changes in the trucking market in response to the standards in this 
program. For example, input-output tables could be used to determine 
the trucking cost share of the total delivered price of a commodity. 
Using the change in trucking prices described in the aggregate 
approach, the product-specific demand elasticities could be used to 
calculate the change in sales and shipments for each product. The 
change in shipment increases could then be weighted by the share of the 
trucking industry total, and then summed to get the total increase in 
trucking output. A simplifying assumption could then be made that the 
increase in output results in an increase in VMT. To the best of our 
knowledge, this type of data has not yet been collected. We did not 
receive any new information in response to our request for comments in 
the proposal, therefore we were unable to use this methodology for 
estimating the rebound effect for this final action.
(iii) Econometric Estimates
    Similar to the methodology used to estimate the light-duty rebound 
effect, the HD rebound effect could be modeled econometrically by 
estimating truck demand as a function of economic activity (e.g., GDP) 
and different input prices (e.g., vehicle prices, driver wages, and 
fuel costs per mile). This type of econometric model could be estimated 
for either truck VMT or ton-miles as a measure of demand. The resulting 
elasticity estimates could then be used to determine the change in 
trucking demand, given the change in fuel cost and truck prices per 
mile from these standards. One of the challenges associated with an 
econometric analysis is the potential for omitted variable bias, which 
could either overstate or understate the potential rebound effect if 
the omitted variable is correlated with the controlled variables.
(iv) Other Modeling Approaches
    Regulation of the heavy-duty industry has been studied in more 
detail in Europe, as the European Commission (EC) has considered 
allowing longer and heavier trucks for freight transport. Part of the 
analysis considered by the EC relies on country-specific modeling of 
changes in the freight sector that would result from changes in 
regulations.\498\ This approach attempts to explicitly calculate modal 
shift decisions and impacts on GHG emissions. Although similar types of 
analysis have not been conducted extensively in the United States, 
research is currently underway that explores the potential for 
intermodal shifting in the United States. For example, Winebrake and 
Corbett have developed the Geospatial Intermodal Freight Transportation 
model, which evaluates the potential for GHG emissions reductions based 
on mode shifting, given existing limitations of infrastructure and 
other route characteristics in the United States.\499\ This model 
connects multiple road, rail, and waterway transportation networks and 
embeds activity-based calculations in the model. Within this intermodal 
network, the model assigns various economic, time-of-delivery, energy, 
and environmental attributes to real-world goods movement routes. The 
model can then calculate different network optimization scenarios, 
based on changes in prices and policies.\500\ However, more work is 
needed in this area to determine whether this type of methodology is 
appropriate for the purposes of capturing the rebound effect. 
Therefore, we have not been able to use this methodology for estimating 
the rebound effect for this final action.
---------------------------------------------------------------------------

    \498\ Christidis and Leduc, ``Longer and Heavier Vehicles for 
freight transport,'' European Commission Joint Research Center's 
Institute for Prospective Technology Studies, 2009.
    \499\ Winebrake, James and Corbett, James J. (2010). ``Improving 
the Energy Efficiency and Environmental Performance of Goods 
Movement,'' in Sperling, Daniel and James S. Cannon (2010) Climate 
and Transportation Solutions: Findings from the 2009 Asilomar 
Conference on Transportation and Energy Policy. See http://www.its.ucdavis.edu/events/2009book/Chapter13.pdf (Docket ID: EPA-
HQ-OAR-2010-0162-0011)
    \500\ Winebrake, J. J.; Corbett, J. J.; Falzarano, A.; Hawker, 
J. S.; Korfmacher, K.; Ketha, S.; Zilora, S., Assessing Energy, 
Environmental, and Economic Tradeoffs in Intermodal Freight 
Transportation, Journal of the Air & Waste Management Association, 
58(8), 2008 (Docket ID: EPA-HQ-OAR-2010-0162-0008).
---------------------------------------------------------------------------

(c) Estimates of the Rebound Effect
    The aggregate methodology was used by Cambridge Systematics, Inc. 
(CSI) to show several examples of the magnitude of the rebound 
effect.\501\ In their paper commissioned by the NAS in support of the 
recent HD report, CSI calculated an effective rebound effect for two 
different technology cost and fuel savings scenarios associated with an 
example Class 8 truck. Scenario 1 increased average fuel economy from 
5.59 mpg to 6.8 mpg, with an additional cost of $22,930. Scenario 2 
increased the average fuel economy to 9.1 mpg, at an incremental cost 
of $71,630 per vehicle. The CSI examples provided estimates using a 
range of own-price elasticities (-0.5 to -1.5) and cross-price 
elasticities (0.35 to 0.59) from the literature. Based on these two 
scenarios and a number of simplifying assumptions to aid the 
calculations, CSI found a rebound effect of 11-31 percent for Scenario 
1 and 5-16 percent for

[[Page 57329]]

Scenario 2 when the fuel savings from reduced rail usage were not taken 
into account (``First rebound effect''). When the fuel savings from 
reduced rail usage were included in the calculations, the overall 
rebound effect was between 9-13 percent for Scenario 1 and 3-15 percent 
for Scenario 2 (``Second Rebound Effect''). See Table VIII-12.
---------------------------------------------------------------------------

    \501\ Cambridge Systematics, Inc., 2009.
---------------------------------------------------------------------------

    CSI included a number of caveats associated with these 
calculations. Namely, the elasticity estimates derived from the 
literature are ``heavily reliant on factors including the type of 
demand measures analyzed (vehicle-miles of travel, ton-miles, or tons), 
analysis geography, trip lengths, markets served, and commodities 
transported.'' Furthermore, the CSI example only focused on Class 8 
combination tractors and did not attempt to quantify the potential 
rebound effect for any other truck classes. Finally, these scenarios 
were characterized as ``sketches'' and were not included in the final 
NAS report. In fact, the NAS report asserted that it is ``not possible 
to provide a confident measure of the rebound effect,'' yet concluded 
that a rebound effect likely exists and that ``estimates of fuel 
savings from regulatory standards will be somewhat misestimated if the 
rebound effect is not considered.''

     Table VIII-12--Range of Rebound Effect Estimates From Cambridge
                    Systematics Aggregate Assessment
------------------------------------------------------------------------
                                            Scenario 1      Scenario 2
                                             (6.8 mpg,       (9.1 mpg,
                                             $22,930)        $71,630)
------------------------------------------------------------------------
``First Rebound Effect'' (increase in             11-31%           5-16%
 truck VMT resulting from decrease in
 operating costs).......................
``Second Rebound Effect'' (net fuel                9-13%           3-15%
 savings when decreases from rail are
 taken into account)....................
------------------------------------------------------------------------

    As an alternative, using the econometric approach, NHTSA has 
estimated the rebound effect in the short run and long run for single 
unit (Class 4-7) and (Class 8) combination tractors. As shown in Table 
VIII-13, the estimates for the long-run rebound effect are larger than 
the estimates in the short run, which is consistent with the theory 
that shippers have more flexibility to change their behavior (e.g., 
restructure contracts or logistics) when they are given more time. In 
addition, the estimates derived from the national data also showed 
larger rebound effects compared to the state data.\502\ One possible 
explanation for the difference in the estimates is that the national 
rebound estimates are capturing some of the impacts of changes in 
economic activity. Historically, large increases in fuel prices are 
highly correlated with economic downturns, and there may not be enough 
variation in the national data to differentiate the impact of fuel 
price changes from changes in economic activity. In contrast, some 
states may see an increase in output when energy prices increase (e.g., 
large oil producing states such as Texas and Alaska); therefore, the 
state data may be more accurately isolating the individual impact of 
fuel price changes.
---------------------------------------------------------------------------

    \502\ NHTSA's estimates of the rebound effect are derived from 
econometric analysis of national and state VMT data reported in 
Federal Highway Administration, Highway Statistics, various 
editions, Tables VM-1 and VM-4. Specifically, the estimates of the 
rebound effect reported in Table VIII-10 are ranges of the estimated 
short-run and long-run elasticities of annual VMT by single-unit and 
combination trucks with respect to fuel cost per mile driven. (Fuel 
cost per mile driven during each year is equal to average fuel price 
per gallon during that year divided by average fuel economy of the 
truck fleet during that same year.) These estimates are derived from 
time-series regression of annual national aggregate VMT for the 
period 1970-2008 on measures of nationwide economic activity, 
including aggregate GDP, the value of durable and nondurable goods 
production, and the volume of U.S. exports and imports of goods, and 
variables affecting the price of trucking services (driver wage 
rates, truck purchase prices, and fuel costs), and from regression 
of VMT for each individual state over the period 1994-2008 on 
similar variables measured at the state level.

 Table VIII-13--Range of Rebound Effect Estimates From NHTSA Econometric
                                Analysis
------------------------------------------------------------------------
                         National data                 State data
  Truck type   ---------------------------------------------------------
                   Short run       Long run        Short run    Long run
------------------------------------------------------------------------
 Single Unit          13-22%          28-45%            3-8%    12-21%
 Combination             N/A          12-14%             N/A    4-5%
------------------------------------------------------------------------

    As discussed throughout this section, there are multiple 
methodologies for quantifying the rebound effect, and these different 
methodologies produce a large range of potential values of the rebound 
effect. However, for the purposes of quantifying the rebound effect for 
this program, we have used a rebound effect with respect to changes in 
fuel costs per mile on the lower range of the long-run estimates. Given 
the fact that the long-run state estimates are generally more 
consistent with the aggregate estimates, for this program we have 
chosen a rebound effect for vocational vehicles (single unit trucks) of 
15 percent that is within the range of estimates from both 
methodologies. Similarly, we have chosen a rebound effect for 
combination tractors of 5 percent.
    To date, no estimates of the HD pickup truck and van rebound effect 
have been cited in the literature. Since these vehicles are used for 
very different purposes than heavy-duty vehicles, it does not 
necessarily seem appropriate to apply one of the heavy-duty estimates 
to the HD pickup trucks and vans. These vehicles are more similar in 
use to large light-duty vehicles, so for the purposes of our analysis, 
we have chosen to apply the light-duty rebound effect of 10 percent to 
this class of vehicles.
    For the purposes of this program, we have not taken into account 
any potential fuel savings or GHG emission reductions from the rail 
sector due to mode shifting. We requested comments on this assumption 
in the proposal, but we did not receive any new data or input.
    Furthermore, we have made a number of simplifying assumptions in 
our calculations, which are discussed in more detail in the RIA. 
Specifically, we have not attempted to capture how current market 
failures might impact the rebound effect. The direction and magnitude 
of the rebound effect in the HD market are expected to vary depending 
on the existence and types of market failures affecting the fuel 
efficiency of the trucking fleet. If firms

[[Page 57330]]

are already accurately accounting for the costs and benefits of these 
technologies and fuel savings, then these regulations would increase 
their net costs, because trucks would already include all the cost-
effective technologies. As a result, the rebound effect would actually 
be negative and truck VMT would decrease as a result of these final 
regulations. However, if firms are not optimizing their behavior today 
due to factors such as lack of reliable information (see Section 
VIII.A. for further discussion), it is more likely that truck VMT would 
increase. If firms recognize their lower net costs as a result of these 
regulations and pass those costs along to their customers, then the 
rebound effect would increase truck VMT. This response assumes that 
trucking rates include both truck purchase costs and fuel costs, and 
that the truck purchase costs included in the rates spread those costs 
over the full expected lifetime of the trucks. If those costs are 
spread over a shorter period, as the expected short payback period 
implies, then those purchase costs will inhibit reduction of freight 
rates, and the rebound effect will be smaller.
    As discussed in more detail in Section VIII.A, if there are market 
failures such as split incentives, estimating the rebound effect may 
depend on the nature of the failures. For example, if the original 
purchaser cannot fully recoup the higher upfront costs through fuel 
savings before selling the vehicle nor pass those costs onto the resale 
buyer, the firm would be expected to raise shipping rates. A firm 
purchasing the truck second-hand might lower shipping rates if the firm 
recognizes the cost savings after operating the vehicle, leading to an 
increase in VMT. Similarly, if there are split incentives and the 
vehicle buyer isn't the same entity that purchases the fuel, than there 
would theoretically be a positive rebound effect. In this scenario, 
fuel savings would lower the net costs to the fuel purchaser, which 
would result in a larger increase in truck VMT.
    If all of these scenarios occur in the marketplace, the net effect 
will depend on the extent and magnitude of their relative effects, 
which are also likely to vary across truck classes (for instance, split 
incentives may be a much larger problem for Class 7 and 8 tractors than 
they are for HD pickup trucks). Additional details on the rebound 
effect are included in the RIA.

F. Class Shifting and Fleet Turnover Impacts

    The agencies considered two additional potential indirect costs, 
benefits, effects, and externalities which may lead to unintended 
consequences of the program to improve the fuel efficiency and reduce 
GHG emissions from HD trucks. The next sections cover the agencies' 
qualitative discussions on potential class shifting and fleet turnover 
effects.
(1) Class Shifting
    Heavy-duty vehicles are typically configured and purchased to 
perform a function. For example, a concrete mixer truck is purchased to 
transport concrete, a combination tractor is purchased to move freight 
with the use of a trailer, and a Class 3 pickup truck could be 
purchased by a landscape company to pull a trailer carrying lawnmowers. 
The purchaser makes decisions based on many attributes of the vehicle, 
including the gross vehicle weight rating of the vehicle which in part 
determines the amount of freight or equipment that can be carried. If 
the final HD National Program impacts either the performance of the 
vehicle or the marginal cost of the vehicle relative to the other 
vehicle classes, then consumers may choose to purchase a different 
vehicle, resulting in the unintended consequence of increased fuel 
consumption and GHG emissions in-use.
    The agencies, along with the NAS panel, found that there is little 
or no literature which evaluates class shifting between trucks.\503\ 
NHTSA and EPA qualitatively evaluated the final rules in light of 
potential class shifting. The agencies looked at four potential cases 
of shifting:--from light-duty pickup trucks to heavy-duty pickup 
trucks; from sleeper cabs to day cabs; from combination tractors to 
vocational vehicles; and within vocational vehicles.
---------------------------------------------------------------------------

    \503\ See 2010 NAS Report, Note 197, page 152.
---------------------------------------------------------------------------

    Light-duty pickup trucks, those with a GVWR of less than 8,500 
pounds, are currently regulated under the existing CAFE program and 
will meet GHG emissions standards beginning in 2012. The increased 
stringency of the light-duty 2012-2016 MY vehicle rule has led some to 
speculate that vehicle consumers may choose to purchase heavy-duty 
pickup trucks that are currently unregulated if the cost of the light-
duty regulation is high relative to the cost to buy the larger heavy-
duty pickup trucks. Since fuel consumption and GHG emissions rise 
significantly with vehicle mass, a shift from light-duty trucks to 
heavy-duty trucks would likely lead to higher fuel consumption and GHG 
emissions, an untended consequence of the regulations. Given the 
significant price premium of a heavy-duty truck (often five to ten 
thousand dollars more than a light-duty pickup), we believe that such a 
class shift would be unlikely even absent this program. With these 
final regulations, any incentive for such a class shift is 
significantly diminished. The final regulations for the HD pickup 
trucks, and similarly for vans, are based on similar technologies and 
therefore reflect a similar expected increase in cost when compared to 
the light-duty GHG regulation. Hence, the combination of the two 
regulations provides little incentive for a shift from light-duty 
trucks to HD trucks. To the extent that our final regulation of heavy-
duty pickups and vans could conceivably encourage a class shift towards 
lighter pickups, this unintended consequence would in fact be expected 
to lead to lower fuel consumption and GHG emissions as the smaller 
light-duty pickups are significantly more efficient than heavy-duty 
pickup trucks.
    The projected cost increases for this final action differ 
significantly between Class 8 day cabs and Class 8 sleeper cabs, 
reflecting our expectation that compliance with the final standards 
will lead truck consumers to specify sleeper cabs equipped with APUs 
while day cab consumers will not. Since Class 8 day cab and sleeper cab 
trucks perform essentially the same function when hauling a trailer, 
this raises the possibility that the higher cost for an APU equipped 
sleeper cab could lead to a shift from sleeper cab to day cab trucks. 
We do not believe that such an intended consequence will occur for the 
following reasons. The addition of a sleeper berth to a tractor cab is 
not a consumer-selectable attribute in quite the same way as other 
vehicle features. The sleeper cab provides a utility that long-distance 
trucking fleets need to conduct their operations--an on-board sleeping 
berth that lets a driver comply with federally-mandated rest periods, 
as required by the Department of Transportation Federal Motor Carrier 
Safety Administration's hours-of-service regulations. The cost of 
sleeper trucks is already higher than the cost of day cabs, yet the 
fleets that need this utility purchase them.\504\ A day cab simply 
cannot provide this utility. The need for this utility would not be 
changed even if the marginal costs to reduce greenhouse gas emissions 
from sleeper cabs exceed the marginal costs to reduce greenhouse gas 
emissions from day

[[Page 57331]]

cabs.\505\ A trucking fleet could decide to put its drivers in hotels 
in lieu of using sleeper berths, and switch to day cabs. However, this 
is unlikely to occur in any great number, since the added cost for the 
hotel stays would far overwhelm differences in the marginal cost 
between day and sleeper cabs. Even if some fleets do opt to buy hotel 
rooms and switch to day cabs, they would be highly unlikely to purchase 
a day cab that was aerodynamically worse than the sleeper cab they 
replaced, since the need for features optimized for long-distance 
hauling would not have changed. So in practice, there would likely be 
little difference to the environment for any switching that might 
occur. Further, while our projected costs assume the purchase of an APU 
for compliance, in fact our regulatory structure would allow compliance 
using a near zero cost software utility that eliminates tractor idling 
after five minutes. Using this compliance approach, the cost difference 
between a Class 8 sleeper cab and day cab due to our final regulations 
is small. We are providing this alternative compliance approach 
reflecting that some sleeper cabs are used in team driving situations 
where one driver sleeps while the other drives. In that situation, an 
APU is unnecessary since the tractor is continually being driven when 
occupied. When it is parked, it will automatically eliminate any 
additional idling through the shutdown software. If trucking companies 
choose this option, then costs based on purchase of APUs may 
overestimate the costs of this program to this sector.
---------------------------------------------------------------------------

    \504\ A baseline tractor price of a new day cab is $89,500 
versus $113,000 for a new sleeper cab based on information gathered 
by ICF in the ``Investigation of Costs for Strategies to Reduce 
Greenhouse Gas Emissions for Heavy-Duty On-Road Vehicles'', July 
2010. Page 3. Docket Identification Number EPA-HQ-OAR-2010-0162-
0044.
    \505\ The average marginal cost difference between sleeper cabs 
and day cabs in the proposal is nearly $6,000.
---------------------------------------------------------------------------

    Class shifting from combination tractors to vocational vehicles may 
occur if a customer deems the additional marginal cost of tractors due 
to the regulation to be greater than the utility provided by the 
tractor. The agencies initially considered this issue when deciding 
whether to include Class 7 tractors with the Class 8 tractors or 
regulate them as vocational vehicles. The agencies' evaluation of the 
combined vehicle weight rating of the Class 7 shows that if these 
vehicles were treated significantly differently from the Class 8 
tractors, then they could be easily substituted for Class 8 tractors. 
Therefore, the agencies are finalizing to include both classes in the 
tractor category. The agencies believe that a shift from tractors to 
vocational vehicles would be limited because of the ability of tractors 
to pick up and drop off trailers at locations which cannot be done by 
vocational vehicles.
    The agencies do not envision that the final regulatory program will 
cause class shifting within the vocational class. The marginal cost 
difference due to the regulation of vocational vehicles is minimal. The 
cost of LRR tires on a per tire basis is the same for all vocational 
vehicles so the only difference in marginal cost of the vehicles is due 
to the number of axles. The agencies believe that the utility gained 
from the additional load carrying capability of the additional axle 
will outweigh the additional cost for heavier vehicles.\506\
---------------------------------------------------------------------------

    \506\ The final rule projects the difference in costs between 
the HHD and MHD vocational vehicle technologies is approximately 
$30.
---------------------------------------------------------------------------

    In conclusion, NHTSA and EPA believe that the final regulatory 
structure for HD trucks does not significantly change the current 
competitive and market factors that determine purchaser preferences 
among truck types. Furthermore, even if a small amount of shifting does 
occur, any resulting GHG impacts are likely to be negligible because 
any vehicle class that sees an uptick in sales is also being regulated 
for fuel efficiency. Therefore, the agencies did not include an impact 
of class shifting on the vehicle populations used to assess the 
benefits of the program.
(2) Fleet Turnover Effect
    A regulation that increases the cost to purchase and/or operate 
trucks could impact whether a consumer decides to purchase a new truck 
and the timing of that purchase. The term pre-buy refers to the idea 
that truck purchases may occur earlier than otherwise planned to avoid 
the additional costs associated with a new regulatory requirement. 
Slower fleet turnover, or low-buys, may occur when owners opt to keep 
their existing truck rather than purchase a new truck due to the 
incremental cost of the regulation.
    The NAS panel discusses the topics associated with HD truck fleet 
turnover. NAS noted that there is some empirical evidence of pre-buy 
behavior in response to the 2004 and 2007 heavy-duty engine emission 
standards, with larger impacts occurring in response to higher 
costs.\507\ However, those regulations increased upfront costs to firms 
without any offsetting future cost savings from reduced fuel purchases. 
In summary, NAS stated that
---------------------------------------------------------------------------

    \507\ See NAS Report, Note 197, pp. 150-151

    * * * during periods of stable or growing demand in the freight 
sector, pre-buy behavior may have significant impact on purchase 
patterns, especially for larger fleets with better access to capital 
and financing. Under these same conditions, smaller operators may 
simply elect to keep their current equipment on the road longer, all 
the more likely given continued improvements in diesel engine 
durability over time. On the other hand, to the extent that fuel 
economy improvements can offset incremental purchase costs, these 
impacts will be lessened. Nevertheless, when it comes to efficiency 
investments, most heavy-duty fleet operators require relatively 
quick payback periods, on the order of two to three years.\508\
---------------------------------------------------------------------------

    \508\ See NAS Report, Note 197, page 151.

    The final regulations are projected to return fuel savings to the 
truck owners that offset the cost of the regulation within a few years 
for vocational vehicles and Class 7 and 8 tractors, the categories 
where the potential for prebuy and delayed fleet turnover are concerns. 
In the case of vocational vehicles, the added cost is small enough that 
it is unlikely to have a substantial effect on purchasing behavior. In 
the case of Class 7 and 8 trucks, the effects of the regulation on 
purchasing behavior will depend on the nature of the market failures 
and the extent to which firms consider the projected future fuel 
savings in their purchasing decisions.
    If trucking firms account for the rapid payback, they are unlikely 
to strategically accelerate or delay their purchase plans at additional 
cost in capital to avoid a regulation that will lower their overall 
operating costs. As discussed in Section VIII.A, this scenario may 
occur if this final program reduces uncertainty about fuel-saving 
technologies. More reliable information about ways to reduce fuel 
consumption allows truck purchasers to evaluate better the benefits and 
costs of additional fuel savings, primarily in the original vehicle 
market, but possibly in the resale market as well.
    Other market failures may leave open the possibility of some pre-
buy or delayed purchasing behavior. Firms may not consider the full 
value of the future fuel savings for several reasons. For instance, 
truck purchasers may not want to invest in fuel efficiency because of 
uncertainty about fuel prices. Another explanation is that the resale 
market may not fully recognize the value of fuel savings, due to lack 
of trust of new technologies or changes in the uses of the vehicles. 
Lack of coordination (also called split incentives--see Section VIII.A) 
between truck purchasers (who emphasize the up-front costs of the 
trucks) and truck operators, who would like the fuel savings, can also 
lead to pre-buy or delayed purchasing behavior. If these market 
failures prevent firms from fully internalizing fuel savings when

[[Page 57332]]

deciding on vehicle purchases, then pre-buy and delayed purchase could 
occur and could result in a slight decrease in the GHG benefits of the 
regulation.
    Thus, whether pre-buy or delayed purchase is likely to play a 
significant role in the truck market depends on the specific behaviors 
of purchasers in that market. Without additional information about 
which scenario is more likely to be prevalent, the Agencies are not 
projecting a change in fleet turnover characteristics due to this 
regulation.

G. Benefits of Reducing CO2 Emissions

(1) Social Cost of Carbon
    EPA has assigned a dollar value to reductions in CO2 
emissions using recent estimates of the social cost of carbon (SCC). 
The SCC is an estimate of the monetized damages associated with an 
incremental increase in carbon emissions in a given year. It is 
intended to include (but is not limited to) changes in net agricultural 
productivity, human health, property damages from increased flood risk, 
and the value of ecosystem services due to climate change. The SCC 
estimates used in this analysis were developed through an interagency 
process that included EPA, DOT/NHTSA, and other executive branch 
entities, and concluded in February 2010. We first used these SCC 
estimates in the benefits analysis for the light-duty 2012-2016 MY 
vehicle rule; see that rule's preamble for a discussion of application 
of the SCC.\509\ The SCC Technical Support Document (SCC TSD) provides 
a complete discussion of the methods used to develop these SCC 
estimates.\510\
---------------------------------------------------------------------------

    \509\ See 2010 Light-Duty Final Rule, Note 5, docket ID EPA-HQ-
OAR-2009-0472-11424.
    \510\ Docket ID EPA-HQ-OAR-2009-0472-114577, Technical Support 
Document: Social Cost of Carbon for Regulatory Impact Analysis Under 
Executive Order 12866, Interagency Working Group on Social Cost of 
Carbon, with participation by Council of Economic Advisers, Council 
on Environmental Quality, Department of Agriculture, Department of 
Commerce, Department of Energy, Department of Transportation, 
Environmental Protection Agency, National Economic Council, Office 
of Energy and Climate Change, Office of Management and Budget, 
Office of Science and Technology Policy, and Department of Treasury 
(February 2010). Also available at http://epa.gov/otaq/climate/regulations.htm.
---------------------------------------------------------------------------

    The interagency group selected four SCC values for use in 
regulatory analyses, which we have applied in this analysis: $5, $22, 
$36, and $67 per metric ton of CO2 emissions in 2010, in 
2009 dollars.511 512 The first three values are based on the 
average SCC from three integrated assessment models, at discount rates 
of 5, 3, and 2.5 percent, respectively. SCCs at several discount rates 
are included because the literature shows that the SCC is quite 
sensitive to assumptions about the discount rate, and because no 
consensus exists on the appropriate rate to use in an intergenerational 
context. The fourth value is the 95th percentile of the SCC from all 
three models at a 3 percent discount rate. It is included to represent 
higher-than-expected impacts from temperature change further out in the 
tails of the SCC distribution. Low probability, high impact events are 
incorporated into all of the SCC values through explicit consideration 
of their effects in two of the three models as well as the use of a 
probability density function for equilibrium climate sensitivity. 
Treating climate sensitivity probabilistically results in more high 
temperature outcomes, which in turn lead to higher projections of 
damages.
---------------------------------------------------------------------------

    \511\ The interagency group decided that these estimates apply 
only to CO2 emissions. Given that warming profiles and 
impacts other than temperature change (e.g., ocean acidification) 
vary across GHGs, the group concluded ``transforming gases into 
CO2-equivalents using GWP, and then multiplying the 
carbon-equivalents by the SCC, would not result in accurate 
estimates of the social costs of non-CO2 gases'' (SCC 
TSD, pg 13).
    \512\ The SCC estimates were converted from 2007 dollars to 2008 
dollars using a GDP price deflator (1.021) and again to 2009 dollars 
using a GDP price deflator (1.009) obtained from the Bureau of 
Economic Analysis, National Income and Product Accounts Table 1.1.4, 
Prices Indexes for Gross Domestic Product.
---------------------------------------------------------------------------

    The SCC increases over time because future emissions are expected 
to produce larger incremental damages as physical and economic systems 
become more stressed in response to greater climatic change. Note that 
the interagency group estimated the growth rate of the SCC directly 
using the three integrated assessment models rather than assuming a 
constant annual growth rate. This helps to ensure that the estimates 
are internally consistent with other modeling assumptions. Table VIII-
14 presents the SCC estimates used in this analysis.
    When attempting to assess the incremental economic impacts of 
carbon dioxide emissions, the analyst faces a number of serious 
challenges. A recent report from the National Academies of Science 
points out that any assessment will suffer from uncertainty, 
speculation, and lack of information about (1) future emissions of 
greenhouse gases, (2) the effects of past and future emissions on the 
climate system, (3) the impact of changes in climate on the physical 
and biological environment, and (4) the translation of these 
environmental impacts into economic damages.\513\ As a result, any 
effort to quantify and monetize the harms associated with climate 
change will raise serious questions of science, economics, and ethics 
and should be viewed as provisional.
---------------------------------------------------------------------------

    \513\ National Research Council (2009). Hidden Costs of Energy: 
Unpriced Consequences of Energy Production and Use. National 
Academies Press. See docket ID EPA-HQ-OAR-2009-0472-11486.
---------------------------------------------------------------------------

    The interagency group noted a number of limitations to the SCC 
analysis, including the incomplete way in which the integrated 
assessment models capture catastrophic and non-catastrophic impacts, 
their incomplete treatment of adaptation and technological change, 
uncertainty in the extrapolation of damages to high temperatures, and 
assumptions regarding risk aversion. The limited amount of research 
linking climate impacts to economic damages makes the interagency 
modeling exercise even more difficult. The interagency group hopes that 
over time researchers and modelers will work to fill these gaps and 
that the SCC estimates used for regulatory analysis by the Federal 
government will continue to evolve with improvements in modeling. 
Additional details on these limitations are discussed in the SCC TSD.
    We received several comments regarding the SCC estimates used to 
analyze the proposed standards. In particular, these commenters 
discussed the incomplete treatment of impacts as well as discount rate 
selection. EPA has reviewed these comments in detail and responded to 
them in the EPA Response to Comments Document for the Joint Rulemaking. 
As noted in that document, the U.S. government intends to revise these 
estimates, taking into account new research findings that were not 
included in the first round, and has set a preliminary goal of 
revisiting the SCC values in the next few years or at such time as 
substantially updated models become available, and to continue to 
support research in this area. The EPA Response to Comments Document 
for the Joint Rulemaking discusses ongoing research in greater detail.
    Applying the global SCC estimates, shown in Table VIII-14, to the 
estimated domestic reductions in CO2 emissions under this 
final program, we estimate the dollar value of the climate related 
benefits for each analysis year. For internal consistency, the annual 
benefits are discounted back to net present value terms using the same 
discount rate as each SCC estimate (i.e., 5%, 3%, and 2.5%) rather than 
3% and 7%.\514\ These estimates are provided in Table VIII-15.
---------------------------------------------------------------------------

    \514\ It is possible that other benefits or costs of final 
regulations unrelated to CO2 emissions will be discounted 
at rates that differ from those used to develop the SCC estimates.

[[Page 57333]]

                                 Table VIII-14--Social Cost of CO2, 2012--2050 a
                                        [in 2009 dollars per metric ton]
----------------------------------------------------------------------------------------------------------------
                                                                          Discount rate and statistic
                                                             ---------------------------------------------------
                            Year                                                            2.5%       3% 95th
                                                              5%  Average  3%  Average    Average     percentile
----------------------------------------------------------------------------------------------------------------
2012........................................................        $5.28       $23.06       $37.53       $70.14
2015........................................................         5.93        24.58        39.57        75.03
2020........................................................         7.01        27.10        42.98        83.17
2025........................................................         8.53        30.43        47.28        93.11
2030........................................................        10.05        33.75        51.58       103.06
2035........................................................        11.57        37.08        55.88       113.00
2040........................................................        13.09        40.40        60.19       122.95
2045........................................................        14.63        43.34        63.59       131.66
2050........................................................        16.18        46.27        66.99       140.37
----------------------------------------------------------------------------------------------------------------
Note:
\a\ The SCC values are dollar-year and emissions-year specific.

                    Table VIII-15--Monetized CO2 Benefits of Vehicle Program, CO2 Emissions a
                                                [Millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                                                                   Benefits
                                                             ---------------------------------------------------
                                                     CO2                                                 95th
                      Year                        Emissions    Avg SCC at   Avg SCC at   Avg SCC at   percentile
                                                  reduction   5% ($5-$16)    3% ($23-    2.5% ($38-   SCC at 3%
                                                    (MMT)          a          $46) a       $67) a     ($70-$140)
                                                                                                          a
----------------------------------------------------------------------------------------------------------------
2020...........................................         37.7         $264       $1,021       $1,619       $3,133
2030...........................................         73.1          734        2,467        3,770        7,532
2040...........................................         90.3        1,182        3,650        5,437       11,108
2050...........................................        103.9        1,682        4,810        6,963       14,590
                                                ----------------------------------------------------------------
    Net Present Valueb.........................  ...........        9,045       46,070       78,037      140,432
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Except for the last row (net present value), the SCC values are dollar-year and emissions-year specific.
\b\ Net present value of reduced CO2 emissions is calculated differently from other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.

H. Non-GHG Health and Environmental Impacts

    This section presents EPA's analysis of the non-GHG health and 
environmental impacts that can be expected to occur as a result of the 
HD National Program. GHG emissions are predominantly the byproduct of 
fossil fuel combustion processes that also produce criteria and 
hazardous air pollutants. The vehicles that are subject to the 
standards are also significant sources of mobile source air pollution 
such as direct PM, NOX, VOCs and air toxics. The standards 
will affect exhaust emissions of these pollutants from vehicles. They 
will also affect emissions from upstream sources related to changes in 
fuel consumption. Changes in ambient ozone, PM2.5, and air 
toxics that will result from the standards are expected to affect human 
health in the form of premature deaths and other serious human health 
effects, as well as other important public health and welfare effects.
    As many commenters noted, it is important to quantify the health 
and environmental impacts associated with the final rules because a 
failure to adequately consider these ancillary co-pollutant impacts 
could lead to an incorrect assessment of their net costs and benefits. 
Moreover, co-pollutant impacts tend to accrue in the near term, while 
any effects from reduced climate change mostly accrue over a time frame 
of several decades or longer.
    This section is organized as follows: the first presents the PM- 
and ozone-related health and environmental impacts associated with the 
final program in calendar year (CY) 2030; the second discusses the 
related co-benefits associated with the model year (MY) analysis of the 
program.\515\
---------------------------------------------------------------------------

    \515\ EPA typically analyzes rule impacts (emissions, air 
quality, costs and benefits) in the year in which they occur; for 
this analysis, we selected 2030 as a representative future year. We 
refer to this analysis as the ``Calendar Year'' (CY) analysis. EPA 
also conducted a separate analysis of the impacts over the model 
year lifetimes of the 2012 through 2016 model year vehicles. We 
refer to this analysis as the ``Model Year'' (MY) analysis. In 
contrast to the CY analysis, the MY lifetime analysis shows the 
lifetime impacts of the program on each of these MY fleets over the 
course of its lifetime.
---------------------------------------------------------------------------

(1) Quantified and Monetized Non-GHG Human Health Benefits of the 2030 
Calendar Year Analysis
    This analysis reflects the impact of the HD National Program in 
2030 compared to a future-year reference scenario without the program 
in place.\516\ Overall, we estimate that the final rules will lead to a 
net decrease in PM2.5-related health impacts. See Section 
VII.D of this preamble for more

[[Page 57334]]

information about the air quality modeling results. While the PM-
related air quality impacts are relatively small, the decrease in 
population-weighted national average PM2.5 exposure results 
in a net decrease in adverse PM-related human health impacts (the 
decrease in national population-weighted annual average 
PM2.5 is 0.005 [mu]g/m\3\).
---------------------------------------------------------------------------

    \516\ The future-year reference scenario to which the program 
impacts are compared in this section assumes no future gains in mpg 
(a ``flat'' scenario). For the final rulemaking, the agencies have 
also conducted a sensitivity analysis relative to the baseline 
assumptions. The alternative baseline assumes annual mpg 
projections, in the absence of the program, which were developed by 
the U.S. Energy Information Administration (EIA) for the Annual 
Energy Outlook (AEO). A description of the alternative baseline can 
be found in RIA Chapter 6. Due to time and resource constraints, EPA 
was unable to conduct full-scale photochemical air quality modeling 
to reflect the final rule impacts relative to this alternative 
baseline.
---------------------------------------------------------------------------

    The air quality modeling also projects decreases in ozone 
concentrations in many areas. While the ozone-related impacts are 
relatively small, the decrease in population-weighted national average 
ozone exposure results in a net decrease in ozone-related health 
impacts (population-weighted maximum 8-hour average ozone decreases by 
0.164 ppb).
    We base our analysis of the program's impact on human health in 
2030 on peer-reviewed studies of air quality and human health 
effects.517 518 These methods are described in more detail 
in the RIA that accompanies this action. Our benefits methods are also 
consistent with recent rulemaking analyses such as the final Transport 
Rule,\519\ the light-duty 2012-2016 MY vehicle rule,\520\ and the final 
Portland Cement National Emissions Standards for Hazardous Air 
Pollutants (NESHAP) RIA.\521\ To model the ozone and PM air quality 
impacts of this final action, we used the Community Multiscale Air 
Quality (CMAQ) model (see Chapter 8.2.2 of the RIA that accompanies 
this preamble). The modeled ambient air quality data serves as an input 
to the Environmental Benefits Mapping and Analysis Program version 4.0 
(BenMAP).\522\ BenMAP is a computer program developed by the U.S. EPA 
that integrates a number of the modeling elements used in previous 
analyses (e.g., interpolation functions, population projections, health 
impact functions, valuation functions, analysis and pooling methods) to 
translate modeled air concentration estimates into health effects 
incidence estimates and monetized benefits estimates.
---------------------------------------------------------------------------

    \517\ U.S. Environmental Protection Agency. (2006). Final 
Regulatory Impact Analysis (RIA) for the Proposed National Ambient 
Air Quality Standards for Particulate Matter. Prepared by: Office of 
Air and Radiation. Retrieved March 26, 2009 at http://www.epa.gov/ttn/ecas/ria.html
    \518\ U.S. Environmental Protection Agency. (2008). Final Ozone 
NAAQS Regulatory Impact Analysis. Prepared by: Office of Air and 
Radiation, Office of Air Quality Planning and Standards. Retrieved 
March 26, 2009 at http://www.epa.gov/ttn/ecas/ria.html.
    \519\ Final Federal Implementation Plans to Reduce Interstate 
Transport of Fine Particulate Matter and Ozone. Signed July 6, 2011. 
Available at http://epa.gov/airtransport/.
    \520\ U.S. Environmental Protection Agency. (2010). Regulatory 
Impact Analysis: Final Rulemaking to Establish Light-Duty Vehicle 
Greenhouse Gas Emission Standards and Corporate Average Fuel Economy 
Standards, EPA-420-R-10-009, April 2010. Available on the Internet: 
http://www.epa.gov/otaq/climate/regulations/420r10009.pdf.
    \521\ U.S. Environmental Protection Agency (U.S. EPA). 2010. 
Regulatory Impact Analysis: National Emission Standards for 
Hazardous Air Pollutants from the Portland Cement Manufacturing 
Industry. Office of Air Quality Planning and Standards, Research 
Triangle Park, NC. Augues. Available on the Internet at http://www.epa.gov/ttn/ecas/regdata/RIAs/portlandcementfinalria.pdf. EPA-
HQ-OAR-2009-0472-0241.
    \522\ Information on BenMAP, including downloads of the 
software, can be found at http://www.epa.gov/ttn/ecas/benmodels.html.
---------------------------------------------------------------------------

    The range of total monetized ozone- and PM-related health impacts 
is presented in Table VIII-16. We present total benefits based on the 
PM- and ozone-related premature mortality function used. The benefits 
ranges therefore reflect the addition of each estimate of ozone-related 
premature mortality (each with its own row in Table VIII-16) to 
estimates of PM-related premature mortality. These estimates represent 
EPA's preferred approach to characterizing a best estimate of benefits. 
As is the nature of Regulatory Impact Analyses (RIAs), the assumptions 
and methods used to estimate air quality benefits evolve to reflect the 
agency's most current interpretation of the scientific and economic 
literature.

                 Table VIII-16--Estimated 2030 Monetized PM- and Ozone-Related Health Benefits a
----------------------------------------------------------------------------------------------------------------
   2030 Total ozone and PM benefits--PM mortality derived from American Cancer Society analysis and Six-Cities
                                                   Analysis a
-----------------------------------------------------------------------------------------------------------------
                                                                     Total benefits           Total Benefits
  Premature ozone mortality function          Reference           (billions, 2009$, 3%     (billions, 2009$, 7%
                                                                   discount rate) b,c       discount rate) b,c
----------------------------------------------------------------------------------------------------------------
Multi-city analyses..................  Bell et al., 2004......  Total: $1.3-$2.4.......  Total: $1.2-$2.2.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6.
                                                                Ozone: $0.55...........  Ozone: $0.55.
                                       Huang et al., 2005.....  Total: $1.6-$2.7.......  Total: $1.6-$2.5.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6
                                                                Ozone: $0.91...........  Ozone: $0.91.
                                       Schwartz, 2005.........  Total: $1.6-$2.6.......  Total: $1.5-$2.5.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6.
                                                                Ozone: $0.83...........  Ozone: $0.83.
Meta-analyses........................  Bell et al., 2005......  Total: $2.4-$3.5.......  Total: $2.4-$3.3.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6.
                                                                Ozone: $1.7............  Ozone: $1.7.
                                       Ito et al., 2005.......  Total: $3.1-$4.2.......  Total: $3.0-$4.0.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6.
                                                                Ozone: $2.4............  Ozone: $2.4.
                                       Levy et al., 2005......  Total: $3.1-$4.2.......  Total: $3.1-$4.0.
                                                                PM: $0.74-$1.8.........  PM: $0.67-$1.6.
                                                                Ozone: $2.4............  Ozone: $2.4.
----------------------------------------------------------------------------------------------------------------
Notes:
 
\a\ Total includes premature mortality-related and morbidity-related ozone and PM2.5 benefits. Range was
  developed by adding the estimate from the ozone premature mortality function to the estimate of PM2.5-related
  premature mortality derived from either the ACS study (Pope et al., 2002) or the Six-Cities study (Laden et
  al., 2006).
\b\ Note that total benefits presented here do not include a number of unquantified benefits categories. A
  detailed listing of unquantified health and welfare effects is provided in Table VIII-17.
\c\ Results reflect the use of both a 3 and 7 percent discount rate, as recommended by EPA's Guidelines for
  Preparing Economic Analyses and OMB Circular A-4. Results are rounded to two significant digits for ease of
  presentation and computation.

[[Page 57335]]

    The benefits in Table VIII-16 include all of the human health 
impacts we are able to quantify and monetize at this time. However, the 
full complement of human health and welfare effects associated with PM 
and ozone remain unquantified because of current limitations in methods 
or available data. We have not quantified a number of known or 
suspected health effects linked with ozone and PM for which appropriate 
health impact functions are not available or which do not provide 
easily interpretable outcomes (e.g., changes in heart rate 
variability). Additionally, we are unable to quantify a number of known 
welfare effects, including reduced acid and particulate deposition 
damage to cultural monuments and other materials, and environmental 
benefits due to reductions of impacts of eutrophication in coastal 
areas. These are listed in Table VIII-17. As a result, the health 
benefits quantified in this section are likely underestimates of the 
total benefits attributable to this final action.

     Table VIII-17--Unquantified and Non-Monetized Potential Effects
------------------------------------------------------------------------
                                       Effects not included in analysis--
          Pollutant/effects                       Changes in:
------------------------------------------------------------------------
Ozone Health \a\.....................  Chronic respiratory damage \b\.
                                       Premature aging of the lungs \b\.
                                       Non-asthma respiratory emergency
                                        room visits.
                                       Exposure to UVb (+/-) \e\.
Ozone Welfare........................  Yields for:
                                       --commercial forests.
                                       --some fruits and vegetables.
                                       --non-commercial crops.
                                       Damage to urban ornamental
                                        plants.
                                       Impacts on recreational demand
                                        from damaged forest aesthetics.
                                       Ecosystem functions.
                                       Exposure to UVb (+/-) \e\.
PM Health \c\........................  Premature mortality--short term
                                        exposures.\d\
                                       Low birth weight.
                                       Pulmonary function.
                                       Chronic respiratory diseases
                                        other than chronic bronchitis.
                                       Non-asthma respiratory emergency
                                        room visits.
                                       Exposure to UVb (+/-) \e\.
PM Welfare...........................  Residential and recreational
                                        visibility in non-Class I areas.
                                       Soiling and materials damage.
                                       Damage to ecosystem functions.
                                       Exposure to UVb (+/-) \e\.
Nitrogen and Sulfate Deposition        Commercial forests due to acidic
 Welfare.                               sulfate and nitrate deposition.
                                       Commercial freshwater fishing due
                                        to acidic deposition.
                                       Recreation in terrestrial
                                        ecosystems due to acidic
                                        deposition.
                                       Existence values for currently
                                        healthy ecosystems.
                                       Commercial fishing, agriculture,
                                        and forests due to nitrogen
                                        deposition.
                                       Recreation in estuarine
                                        ecosystems due to nitrogen
                                        deposition.
                                       Ecosystem functions.
                                       Passive fertilization.
CO Health............................  Behavioral effects.
HC/Toxics Health \f\.................  Cancer (benzene, 1,3-butadiene,
                                        formaldehyde, acetaldehyde).
                                       Anemia (benzene).
                                       Disruption of production of blood
                                        components (benzene).
                                       Reduction in the number of blood
                                        platelets (benzene).
                                       Excessive bone marrow formation
                                        (benzene).
                                       Depression of lymphocyte counts
                                        (benzene).
                                       Reproductive and developmental
                                        effects (1,3-butadiene).
                                       Irritation of eyes and mucus
                                        membranes (formaldehyde).
                                       Respiratory irritation
                                        (formaldehyde).
                                       Asthma attacks in asthmatics
                                        (formaldehyde).
                                       Asthma-like symptoms in non-
                                        asthmatics (formaldehyde).
                                       Irritation of the eyes, skin, and
                                        respiratory tract
                                        (acetaldehyde).
                                       Upper respiratory tract
                                        irritation and congestion
                                        (acrolein).
HC/Toxics Welfare....................  Direct toxic effects to animals.
                                       Bioaccumulation in the food
                                        chain.
                                       Damage to ecosystem function.
                                       Odor.
------------------------------------------------------------------------
Notes:
\a\ The public health impact of biological responses such as increased
  airway responsiveness to stimuli, inflammation in the lung, acute
  inflammation and respiratory cell damage, and increased susceptibility
  to respiratory infection are likely partially represented by our
  quantified endpoints.
\b\ The public health impact of effects such as chronic respiratory
  damage and premature aging of the lungs may be partially represented
  by quantified endpoints such as hospital admissions or premature
  mortality, but a number of other related health impacts, such as
  doctor visits and decreased athletic performance, remain unquantified.
\c\ In addition to primary economic endpoints, there are a number of
  biological responses that have been associated with PM health effects
  including morphological changes and altered host defense mechanisms.
  The public health impact of these biological responses may be partly
  represented by our quantified endpoints.
\d\ While some of the effects of short-term exposures are likely to be
  captured in the estimates, there may be premature mortality due to
  short-term exposure to PM not captured in the cohort studies used in
  this analysis. However, the PM mortality results derived from the
  expert elicitation do take into account premature mortality effects of
  short term exposures.

[[Page 57336]]

 
\e\ May result in benefits or disbenefits.
\f\ Many of the key hydrocarbons related to this action are also
  hazardous air pollutants listed in the CAA.

    While there will be impacts associated with air toxic pollutant 
emission changes that result from this final action, we do not attempt 
to monetize those impacts. This is primarily because currently 
available tools and methods to assess air toxics risk from mobile 
sources at the national scale are not adequate for extrapolation to 
incidence estimations or benefits assessment. The best suite of tools 
and methods currently available for assessment at the national scale 
are those used in the National-Scale Air Toxics Assessment (NATA). The 
EPA Science Advisory Board specifically commented in their review of 
the 1996 NATA that these tools were not yet ready for use in a 
national-scale benefits analysis, because they did not consider the 
full distribution of exposure and risk, or address sub-chronic health 
effects.\523\ While EPA has since improved these tools, there remain 
critical limitations for estimating incidence and assessing benefits of 
reducing mobile source air toxics.
---------------------------------------------------------------------------

    \523\ Science Advisory Board. 2001. NATA--Evaluating the 
National-Scale Air Toxics Assessment for 1996--an SAB Advisory. 
http://www.epa.gov/ttn/atw/sab/sabrev.html.
---------------------------------------------------------------------------

    As part of the second prospective analysis of the benefits and 
costs of the Clean Air Act,\524\ EPA conducted a case study analysis of 
the health effects associated with reducing exposure to benzene in 
Houston from implementation of the Clean Air Act. While reviewing the 
draft report, EPA's Advisory Council on Clean Air Compliance Analysis 
concluded that ``the challenges for assessing progress in health 
improvement as a result of reductions in emissions of hazardous air 
pollutants (HAPs) are daunting...due to a lack of exposure-response 
functions, uncertainties in emissions inventories and background 
levels, the difficulty of extrapolating risk estimates to low doses and 
the challenges of tracking health progress for diseases, such as 
cancer, that have long latency periods.'' \525\ EPA continues to work 
to address these limitations; however, we did not have the methods and 
tools available for national-scale application in time for the analysis 
of the final action.\526\
---------------------------------------------------------------------------

    \524\ U.S. Environmental Protection Agency (U.S. EPA). 2011. The 
Benefits and Costs of the Clean Air Act from 1990 to 2020. Office of 
Air and Radiation, Washington, DC. March. Available on the Internet 
at http://www.epa.gov/air/sect812/feb11/fullreport.pdf.
    \525\ U.S. Environmental Protection Agency--Science Advisory 
Board (U.S. EPA-SAB). 2008. Benefits of Reducing Benzene Emissions 
in Houston, 1990-2020. EPA-COUNCIL-08-001. July. Available at http:/
/yosemite.epa.gov/sab/sabproduct.nsf/
D4D7EC9DAEDA8A548525748600728A83/$File/EPA-COUNCIL-08-001-
unsigned.pdf.
    \526\ In April 2009, EPA hosted a workshop on estimating the 
benefits or reducing hazardous air pollutants. This workshop built 
upon the work accomplished in the June 2000 Science Advisory Board/
EPA Workshop on the Benefits of Reductions in Exposure to Hazardous 
Air Pollutants, which generated thoughtful discussion on approaches 
to estimating human health benefits from reductions in air toxics 
exposure, but no consensus was reached on methods that could be 
implemented in the near term for a broad selection of air toxics. 
Please visit http://epa.gov/air/toxicair/2009workshop.html for more 
information about the workshop and its associated materials.
---------------------------------------------------------------------------

    EPA is also unaware of specific information identifying any effects 
on listed endangered species from the small fluctuations in pollutant 
concentrations associated with this program (see Section VII.D). 
Furthermore, our current modeling tools are not designed to trace 
fluctuations in ambient concentration levels to potential impacts on 
particular endangered species.
(a) Quantified Human Health Impacts
    Table VIII-18 and Table VIII-19 present the annual PM2.5 
and ozone health impacts, respectively, in the 48 contiguous U.S. 
states associated with the HD National Program for 2030. For each 
endpoint presented in Table VIII-18 and Table VIII-19, we provide both 
the mean estimate and the 90 percent confidence interval.
    Using EPA's preferred estimates, based on the American Cancer 
Society (ACS) and Six-Cities studies and no threshold assumption in the 
model of mortality, we estimate that the final rules will result in 
between 78 and 200 cases of avoided PM2.5-related premature 
mortalities annually in 2030. As a sensitivity analysis, when the range 
of expert opinion is used, we estimate between 26 and 260 fewer 
premature mortalities in 2030 (see Table 8-14 in the RIA that 
accompanies this action). For ozone-related premature mortality in 
2030, we estimate a range of between 54 to 240 fewer premature 
mortalities.

         Table VIII-18--Estimated PM2.5-Related Health Impacts a
------------------------------------------------------------------------
                                                            2030 Annual
                                                           reduction in
                      Health effect                       incidence (5th-
                                                               95th
                                                            percentile)
------------------------------------------------------------------------
Premature Mortality--Derived from epidemiology
 literature \b\
    Adult, age 30+, ACS Cohort Study (Pope et al., 2002)     78 (30-130)
    Adult, age 25+, Six-Cities Study (Laden et al.,        200 (110-290)
     2006)..............................................
    Infant, age 18) \d\      45 (32-52)
Emergency room visits for asthma (age 18 years and           81 (48-120)
 younger)...............................................
Acute bronchitis, (children, age 8-12)..................     130 (0-270)
Lower respiratory symptoms (children, age 7-14).........     1,600 (750-
                                                                  2,400)
Upper respiratory symptoms (asthmatic children, age 9-       1,200 (370-
 18)....................................................          2,000)
Asthma exacerbation (asthmatic children, age 6-18)......     1,400 (160-
                                                                  4,000)
Work loss days..........................................   9,700 (8,500-
                                                                 11,000)
Minor restricted activity days (adults age 18-65).......  57,000 (48,000-
                                                                 66,000)
------------------------------------------------------------------------
Notes:
\a\ Incidence is rounded to two significant digits. Estimates represent
  incidence within the 48 contiguous United States.
\b\ PM-related adult mortality based upon the American Cancer Society
  (ACS) Cohort Study (Pope et al., 2002) and the Six-Cities Study (Laden
  et al., 2006). Note that these are two alternative estimates of adult
  mortality and should not be summed. PM-related infant mortality based
  upon a study by Woodruff, Grillo, and Schoendorf, (1997).\527\
\c\ Respiratory hospital admissions for PM include admissions for
  chronic obstructive pulmonary disease (COPD), pneumonia and asthma.
\d\ Cardiovascular hospital admissions for PM include total
  cardiovascular and subcategories for ischemic heart disease,
  dysrhythmias, and heart failure.

     
---------------------------------------------------------------------------

    \527\ Woodruff, T.J., J. Grillo, and K.C. Schoendorf. 1997. 
``The Relationship Between Selected Causes of Postneonatal Infant 
Mortality and Particulate Air Pollution in the United States.'' 
Environmental Health Perspectives 105(6):608-612.

[[Page 57337]]

         Table VIII-19--Estimated Ozone-Related Health Impacts a
------------------------------------------------------------------------
                                                            2030 Annual
                                                           reduction in
                      Health effect                          incidence
                                                             (5th-95th
                                                            percentile)
------------------------------------------------------------------------
Premature Mortality, All ages \b\ Multi-City Analyses:
    Bell et al. (2004)--Non-accidental..................      54 (23-84)
    Huang et al. (2005)--Cardiopulmonary................     90 (43-140)
    Schwartz (2005)--Non-accidental.....................     82 (34-130)
Meta-analyses:
    Bell et al. (2005)--All cause.......................    170 (96-250)
    Ito et al. (2005)--Non-accidental...................   240 (160-320)
    Levy et al. (2005)--All cause.......................   240 (180-310)
Hospital admissions--respiratory causes (adult, 65 and      510 (69-870)
 older) \c\.............................................
Hospital admissions--respiratory causes (children, under   320 (160-470)
 2).....................................................
Emergency room visit for asthma (all ages)..............     230 (0-630)
Minor restricted activity days (adults, age 18-65)......         300,000
                                                          (150,000-450,0
                                                                     00)
School absence days.....................................         120,000
                                                          (52,000-170,00
                                                                       0
------------------------------------------------------------------------
Notes:
\a\ Incidence is rounded to two significant digits. Estimates represent
  incidence within the 48 contiguous U.S.
\b\ Estimates of ozone-related premature mortality are based upon
  incidence estimates derived from several alternative studies: Bell et
  al. (2004); Huang et al. (2005); Schwartz (2005); Bell et al. (2005);
  Ito et al. (2005); Levy et al. (2005). The estimates of ozone-related
  premature mortality should therefore not be summed.
\c\ Respiratory hospital admissions for ozone include admissions for all
  respiratory causes and subcategories for COPD and pneumonia.

(b) Monetized Benefits
    Table VIII-20 presents the estimated monetary value of changes in 
the incidence of ozone and PM2.5-related health effects. All 
monetized estimates are stated in 2009$. These estimates account for 
growth in real gross domestic product (GDP) per capita between the 
present and 2030. Our estimate of total monetized benefits in 2030 for 
the program, using the ACS and Six-Cities PM mortality studies and the 
range of ozone mortality assumptions, is between $1.3 and $4.2 billion, 
assuming a 3 percent discount rate, or between $1.2 and $4.0 billion, 
assuming a 7 percent discount rate.

   Table VIII-20--Estimated Monetary Value of Changes in Incidence of
                   Health and Welfare Effects in 2030
                          [Millions, 2009$] a b
------------------------------------------------------------------------
   PM2.5-Related health effect           (5th and 95th Percentile)
------------------------------------------------------------------------
Premature Mortality--Derived from
 Epidemiology Studies:c d
    Adult, age 30+--ACS study
     (Pope et al., 2002):
        3% discount rate.........  $680 ($87-$1,800)
        7% discount rate.........  $620 ($79-$1,600)
    Adult, age 25+--Six-Cities
     study (Laden et al., 2006):
        3% discount rate.........  $1,800 ($250-$4,300)
        7% discount rate.........  $1,600 ($220-$3,900)
    Infant Mortality,  The exclusion of potentially significant and unquantified 
benefit categories (such as health, odor, and ecological benefits of 
reduction in air toxics, ozone, and PM);
     Errors in measurement and projection for variables such as 
population growth;
     Uncertainties in the estimation of future year emissions 
inventories and air quality;
     Uncertainty in the estimated relationships of health and 
welfare effects to changes in pollutant concentrations including the 
shape of the C-R function, the size of the effect estimates, and the 
relative toxicity of the many components of the PM mixture;
     Uncertainties in exposure estimation; and
     Uncertainties associated with the effect of potential 
future actions to limit emissions.
    As Table VIII-20 indicates, total benefits are driven primarily by 
the reduction in premature mortalities each year. Some key assumptions 
underlying the premature mortality estimates include the following, 
which may also contribute to uncertainty:
     Inhalation of fine particles is causally associated with 
premature death at concentrations near those experienced by most 
Americans on a daily basis. Although biological mechanisms for this 
effect have not yet been completely established, the weight of the 
available epidemiological, toxicological, and experimental evidence 
supports an assumption of causality. The impacts of including a 
probabilistic representation of causality were explored in the expert 
elicitation-based results of the PM NAAQS RIA.
     All fine particles, regardless of their chemical 
composition, are equally potent in causing premature mortality. This is 
an important assumption, because PM produced via transported precursors 
emitted from heavy-duty engines may differ significantly from PM 
precursors released from electric generating units and other industrial 
sources. However, no clear scientific grounds exist for supporting 
differential effects estimates by particle type.
     The C-R function for fine particles is approximately 
linear within the range of ambient concentrations under consideration. 
Thus, the estimates include health benefits from reducing fine 
particles in areas with varied concentrations of PM, including both 
regions that may be in attainment with PM2.5 standards and 
those that are at risk of not meeting the standards.
     There is uncertainty in the magnitude of the association 
between ozone and premature mortality. The range of ozone benefits 
associated with the coordinated strategy is estimated based on the risk 
of several sources of ozone-related mortality effect estimates. In a 
report on the estimation of ozone-related premature mortality published 
by the National Research Council, a panel of experts and reviewers 
concluded that short-term exposure to ambient ozone is likely to 
contribute to premature deaths and that ozone-related mortality should 
be included in estimates of the health benefits of reducing ozone 
exposure.\528\ EPA has requested advice from the National Academy of 
Sciences on how best to quantify uncertainty in the relationship 
between ozone exposure and premature mortality in the context of 
quantifying benefits.
---------------------------------------------------------------------------

    \528\ National Research Council (NRC), 2008. Estimating 
Mortality Risk Reduction and Economic Benefits from Controlling 
Ozone Air Pollution. The National Academies Press: Washington, DC.
---------------------------------------------------------------------------

    Despite the uncertainties described above, we believe this analysis 
provides a conservative estimate of the estimated non-GHG health and 
environmental benefits of the standards in future years because of the 
exclusion of potentially significant benefit categories that are not 
quantifiable at this time. Acknowledging benefits omissions and 
uncertainties, we present a best estimate of the total benefits based 
on our interpretation of the best available scientific literature and 
methods supported by EPA's technical peer review panel, the Science 
Advisory Board's Health Effects Subcommittee (SAB-HES). The National 
Academies of Science (NRC, 2002) has also reviewed EPA's methodology 
for analyzing the health benefits of measures taken to reduce air 
pollution. EPA addressed many of these comments in the analysis of the 
final PM NAAQS.529 530 This analysis incorporates this work 
to the extent possible.
---------------------------------------------------------------------------

    \529\ National Research Council (NRC). 2002. Estimating the 
Public Health Benefits of Proposed Air Pollution Regulations. The 
National Academies Press: Washington, DC.
    \530\ U.S. Environmental Protection Agency. October 2006. Final 
Regulatory Impact Analysis (RIA) for the Proposed National Ambient 
Air Quality Standards for Particulate Matter. Prepared by: Office of 
Air and Radiation. Available at http://www.epa.gov/ttn/ecas/ria.html.
---------------------------------------------------------------------------

(2) Non-GHG Human Health Benefits of the Model Year (MY) Analysis
    As described in Section VII, the final standards will reduce 
emissions of several criteria and toxic pollutants and precursors. EPA 
typically analyzes rule

[[Page 57339]]

impacts (emissions, air quality, costs and benefits) in the year in 
which they occur; for the analysis of non-GHG ambient air quality and 
health impacts, we selected 2030 as a representative future year since 
resource and time constraints precluded EPA from considering multiple 
calendar years. We refer to this analysis as the ``Calendar Year'' (CY) 
analysis because the benefits of the program reflect impacts across all 
regulated vehicles in a calendar year.
    EPA also conducted a separate analysis of the impacts over the 
model year lifetimes of the 2014 through 2018 model year vehicles. We 
refer to this analysis as the ``Model Year'' (MY) analysis (See Chapter 
6 of the RIA that accompanies this preamble). In contrast to the CY 
analysis, the MY analysis estimates the impacts of the program on each 
MY fleet over the course of its lifetime. Due to analytical and 
resource limitations, however, MY non-GHG emissions (direct PM, VOCs, 
NO2 and SO2) were not estimated for this 
analysis. Because MY impacts are measured in relation to only the 
lifetime of a particular vehicle model year (2014, 2015, 2016, 2017, 
and 2018), and assumes no additional controls to model year vehicles 
beyond 2018, the impacts are smaller than if the impacts of all 
regulated vehicles were considered. We therefore expect that the non-
GHG health-related benefits associated with the MY analysis will be 
smaller than those estimated for the CY analysis, both in a given year 
(such as 2030) and in present value terms across a given time period 
(such as 2014-2050).

I. Energy Security Impacts

    The HD National Program is designed to reduce fuel consumption and 
GHG emissions in medium and heavy-duty (HD) vehicles, which will result 
in improved fuel efficiency and, in turn, help to reduce U.S. petroleum 
imports. A reduction of U.S. petroleum imports reduces both financial 
and strategic risks caused by potential sudden disruptions in the 
supply of imported petroleum to the U.S. This reduction in risk is a 
measure of improved U.S. energy security. This section summarizes the 
agencies' estimates of U.S. oil import reductions and energy security 
benefits of the final HD National Program. Additional discussion of 
this issue can be found in Chapter 9.7 of the RIA.
(1) Implications of Reduced Petroleum Use on U.S. Imports
    In 2008, U.S. petroleum import expenditures represented 21 percent 
of total U.S. imports of all goods and services.\531\ In 2008, the 
United States imported 66 percent of the petroleum it consumed, and the 
transportation sector accounted for 70 percent of total U.S. petroleum 
consumption. This compares to approximately 37 percent of petroleum 
from imports and 55 percent of consumption from petroleum in the 
transportation sector in 1975.\532\ It is clear that petroleum imports 
have a significant impact on the U.S. economy.
---------------------------------------------------------------------------

    \531\ Source: U.S. Bureau of Economic Analysis, U.S. 
International Transactions Accounts Data, as shown on June 24, 2009.
    \532\ Source: U.S. Department of Energy, Annual Energy Review 
2008, Report No. DOE/EIA-0384(2008), Tables 5.1 and 5.13c, June 26, 
2009.
---------------------------------------------------------------------------

    Requiring lower GHG vehicle technology and fuel efficient 
technology in HD vehicles in the U.S. is expected to lower U.S. oil 
imports. EPA used the MOVES model to estimate the fuel savings due to 
this program. A detailed explanation of the MOVES model can be found in 
Chapter 5 of the RIA.
    Based on a detailed analysis of differences in fuel consumption, 
petroleum imports, and imports of refined petroleum products and crude 
oil using the Reference Case presented in the Energy Information 
Administration's Annual Energy Outlook (AEO) 2011 Early Release, EPA 
and NHTSA estimate that approximately 50 percent of the reduction in 
fuel consumption resulting from adopting improved GHG emissions 
standards and fuel efficiency standards is likely to be reflected in 
reduced U.S. imports of refined fuel, while the remaining 50 percent is 
expected to be reflected in reduced domestic fuel refining. Of this 
latter figure, 90 percent is anticipated to reduce U.S. imports of 
crude petroleum for use as a refinery feedstock, while the remaining 10 
percent is expected to reduce U.S. domestic production of crude 
petroleum. Thus, on balance, each gallon of fuel saved as a consequence 
of the HD GHG and fuel efficiency standards is anticipated to reduce 
total U.S. imports of petroleum by 0.95 gallons.\533\ The agencies' 
estimates of the reduction in U.S. oil imports from this program for 
selected years, in millions of barrels per day, are presented in Table 
VIII-21 below. These estimates assume that the fuel efficiency of HD 
vehicles remains constant in the baseline.
---------------------------------------------------------------------------

    \533\ This figure is calculated as 0.50 + 0.50*0.9 = 0.50 + 0.45 
= 0.95.

 Table VIII-21--U.S. Oil Import Reductions From the HD National Program
                           for Selected Years
                   [Millions of barrels per day, mmbd]
------------------------------------------------------------------------
                             Year                                 mmbd
------------------------------------------------------------------------
2020.........................................................      0.202
2030.........................................................      0.393
2040.........................................................      0.489
2050.........................................................      0.566
------------------------------------------------------------------------

(2) Energy Security Implications
    In order to understand the energy security implications of reducing 
U.S. petroleum imports, EPA worked with Oak Ridge National Laboratory 
(ORNL), which has developed approaches for evaluating the economic 
costs and energy security implications of oil use. The energy security 
estimates provided below are based upon a methodology developed in a 
peer-reviewed study entitled ``The Energy Security Benefits of Reduced 
Oil Use, 2006-2015, '' completed in March 2008. This study is included 
as part of the docket for this final action.534 535
---------------------------------------------------------------------------

    \534\ Leiby, Paul N., ``Estimating the Energy Security Benefits 
of Reduced U.S. Oil Imports'' Oak Ridge National Laboratory, ORNL/
TM-2007/028, Final Report, 2008. (Docket EPA-HQ-OAR-2010-0162).
    \535\ The ORNL study ``The Energy Security Benefits of Reduced 
Oil Use, 2006-2015,'' completed in March 2008, is an update version 
of the approach used for estimating the energy security benefits of 
U.S. oil import reductions developed in an ORNL 1997 Report by 
Leiby, Paul N., Donald W. Jones, T. Randall Curlee, and Russell Lee, 
entitled ``Oil Imports: An Assessment of Benefits and Costs.'' 
(Docket EPA-HQ-OAR-2010-0162).
---------------------------------------------------------------------------

    When conducting this analysis, ORNL considered the full economic 
cost of importing petroleum into the United States. The economic cost 
of importing petroleum into the U.S. is defined to include two 
components in addition to the purchase price of petroleum itself. These 
are: (1) The higher costs for oil imports resulting from the effect of 
increasing U.S. import demand on the world oil price and on the market 
power of the Organization of the Petroleum Exporting Countries (i.e., 
the ``demand'' or ``monopsony'' costs); and (2) the risk of reductions 
in U.S. economic output and disruption of the U.S. economy caused by 
sudden disruptions in the supply of imported petroleum to the U.S. 
(i.e., macroeconomic disruption/adjustment costs). Maintaining a U.S. 
military presence to help secure stable oil supply from potentially 
vulnerable regions of the world was not included in this analysis 
because its attribution to particular missions or activities is hard to 
quantify.

[[Page 57340]]

    For this action, ORNL estimated energy security premiums by 
incorporating the most recent available AEO 2011 Early Release oil 
price forecasts and market trends. Energy security premiums for the 
years 2020, 2030, 2040, and 2050 are presented in Table VIII-22, as 
well as a breakdown of the components of the energy security premiums 
for each of these years.\536\ The components of the energy security 
premiums and their values are discussed in detail in Chapter 9.7 of the 
RIA.
---------------------------------------------------------------------------

    \536\ AEO 2011 forecasts energy market trends and values only to 
2035. The energy security premium estimates post-2035 were assumed 
to be the 2035 estimate.

                            Table VIII-22--Energy Security Premiums in Selected Years
                                                 [2009$/Barrel]
----------------------------------------------------------------------------------------------------------------
                                                              Macroeconomic disruption/
           Year (range)                     Monopsony              adjustment costs          Total mid-point
----------------------------------------------------------------------------------------------------------------
2020..............................                   $11.29                     $7.11                    $18.41
                                             ($3.86-$21.32)            ($3.50-$11.40)            ($9.70-$28.94)
2030..............................                   $11.17                     $8.32                    $19.49
                                             ($3.92-$20.58)            ($4.04-$13.33)           ($10.49-$29.63)
2035..............................                   $10.56                     $8.71                    $19.27
                                             ($3.69-$19.62)            ($3.86-$14.35)           ($10.32-$29.13)
----------------------------------------------------------------------------------------------------------------

    The literature on the energy security for the last two decades has 
routinely combined the monopsony and the macroeconomic disruption 
components when calculating the total value of the energy security 
premium. However, in the context of using a global SCC value, the 
question arises: how should the energy security premium be determined 
when a global perspective is taken? Monopsony benefits represent 
avoided payments by the United States to oil producers in foreign 
countries that result from a decrease in the world oil price as the 
U.S. decreases its consumption of imported oil.
    Several commenters commented on the agencies' energy security 
analysis of this program. The Conservative Law Foundation, Interfaith 
Care for Creation, Environmental Defense Fund and American Lung 
Association (EDF/ALA) and R. Desjardin noted that the standards in this 
program will increase our national security by decreasing U.S. 
dependence on foreign oil imports. The Competitive Enterprise Institute 
(CEI) felt that there is no relationship between reduced U.S. oil 
imports and U.S. energy security; the commenter sees no relationship 
between reduced oil imports and, for example, the number of hijackings, 
bombings, and other terrorist-related activities that have occurred 
through time. CBD commented that the benefit of the reduction of 
military costs associated with maintaining a secure oil supply should 
be fully accounted for, and EDF recommended a more extensive analysis 
of the external security costs of oil dependence.
    The agencies recognize that potential national and energy security 
risks exist due to the possibility of tension over oil supplies. Much 
of the world's oil and gas supplies are located in countries facing 
social, economic, and demographic challenges, thus making them even 
more vulnerable to potential local instability. For example, in 2010 
just over 40 percent of world oil supply came from OPEC nations, and 
this share is not expected to decline in the AEO 2011 projections 
through 2030. Approximately 28 percent of global supply is from Persian 
Gulf countries alone. As another measure of concentration, of the 137 
countries/principalities that export either crude oil or refined 
petroleum product, the top 12 have recently accounted for over 55 
percent of exports.\537\ Eight of these countries are members of OPEC, 
and a 9th is Russia.\538\ In a market where even a 1-2 percent supply 
loss raises prices noticeably, and where a 10 percent supply loss could 
lead to a significant price shock, this regional concentration is of 
concern. Historically, the countries of the Middle East have been the 
source of eight of the ten major world oil disruptions \539\ with the 
9th originating in Venezuela, an OPEC member.
---------------------------------------------------------------------------

    \537\ Based on data from the CIA, combining various recent 
years, https://www.cia.gov/library/publications/the-world-factbook/rankorder/2176rank.html.
    \538\ The other three are Norway, Canada, and the EU, an 
exporter of product.
    \539\ IEA 2011 ``IEA Response System for Oil Supply 
Emergencies''.
---------------------------------------------------------------------------

    Because of U.S. dependence on oil, the military could be called on 
to protect energy resources through such measures as securing shipping 
lanes from foreign oil fields. To maintain such military effectiveness 
and flexibility, the Department of Defense identified in the 
Quadrennial Defense Review that it is ``increasing its use of renewable 
energy supplies and reducing energy demand to improve operational 
effectiveness, reduce greenhouse gas emissions in support of U.S. 
climate change initiatives, and protect the Department from energy 
price fluctuations.'' \540\ The Department of the Navy has also stated 
that the Navy and Marine Corps rely far too much on petroleum, which 
``degrades the strategic position of our country and the tactical 
performance of our forces. The global supply of oil is finite, it is 
becoming increasingly difficult to find and exploit, and over time cost 
continues to rise.'' \541\
---------------------------------------------------------------------------

    \540\ U.S. Department of Defense. 2010. Quadrennial Defense 
Review Report. Secretary of Defense: Washington, DC 128 pages.
    \541\ The Department of the Navy's Energy Goals (http://www.navy.mil/features/Navy_EnergySecurity.pdf) (Last accessed May 
31, 2011).
---------------------------------------------------------------------------

    In remarks given to the White House Energy Security Summit on April 
26, 2011, Deputy Security of Defense William J. Lynn, III noted the 
direct impact of energy security on military readiness and flexibility. 
According to Deputy Security Lynn, ``Today, energy technology remains a 
critical element of our military superiority. Addressing energy needs 
must be a fundamental part of our military planning.'' \542\
---------------------------------------------------------------------------

    \542\ U.S. Department of Defense, Speech: Remarks at the White 
House Energy Security Summit. Tuesday, April 26, 2011. (http://www.defense.gov/speeches/speech.aspx?speechid=1556) (Last accessed 
May 31, 2011).
---------------------------------------------------------------------------

    Thus, to the degree to which the final rules reduce reliance upon 
imported energy supplies or promotes the development of technologies 
that can be deployed by either consumers or the nation's defense 
forces, the United States could expect benefits related to national 
security, reduced energy costs, and increased energy supply. These 
benefits are why President Obama has identified this program as a key 
component for improving energy efficiency and putting America on a

[[Page 57341]]

path to reducing oil imports in the Blueprint for a Secure Energy 
Future.\543\
---------------------------------------------------------------------------

    \543\ The White House, Blueprint for a Secure Energy Future 
(March 30, 2011) (http://www.whitehouse.gov/sites/default/files/blueprint_secure_energy_future.pdf) (Last accessed May 27, 2011).
---------------------------------------------------------------------------

    Although the agencies recognize that there clearly is a benefit to 
the United States from reducing dependence on foreign oil, the agencies 
have been unable to calculate the monetary benefit that the United 
States will receive from the improvements in national security expected 
to result from this program. In contrast, the other portion of the 
energy security premium, the U.S. macroeconomic disruption and 
adjustment cost that arises from U.S. petroleum imports, is included in 
the energy security benefits estimated for this program. To summarize, 
the agencies have included only the macroeconomic disruption portion of 
the energy security benefits to estimate the monetary value of the 
total energy security benefits of this program. The agencies have 
calculated energy security in very specific terms, as the reduction of 
both financial and strategic risks caused by potential sudden 
disruptions in the supply of imported petroleum to the U.S. Reducing 
the amount of oil imported reduces those risks, and thus increases the 
nation's energy security.
    Another commenter, citing Administration guidelines (OMB Circular 
A-4) for conducting economic analyses, felt that the agency should 
include the monopsony benefit as part of its overall costs and benefits 
analysis. After reviewing the guidelines cited by the commenter, the 
agencies have concluded that excluding the monopsony benefit from its 
overall costs and benefits analysis continues to be appropriate when a 
global perspective is taken. However, the agencies recognize that the 
monopsony benefit has distributional impacts for the U.S., and continue 
to describe and discuss the monopsony benefit in this section of the 
Preamble.
    The total annual energy security benefits for the final HD National 
Program are reported in Table VIII-23 for the years 2020, 2030, 2040 
and 2050.

    Table VIII-23--Total Annual Energy Security Benefits From the HD
              National Program in 2020, 2030, 2040 and 2050
                            [Millions, 2009$]
------------------------------------------------------------------------
                         Year                               Benefits
------------------------------------------------------------------------
2020..................................................              $499
2030..................................................             1,132
2040..................................................             1,477
2050..................................................             1,710
------------------------------------------------------------------------

J. Other Impacts

(i) Noise, Congestion and Accidents
    Increased vehicle use associated with a positive rebound effect 
also contributes to increased traffic congestion, motor vehicle 
accidents, and highway noise. Depending on how the additional travel is 
distributed throughout the day and on where it takes place, additional 
vehicle use can contribute to traffic congestion and delays by 
increasing traffic volumes on facilities that are already heavily 
traveled during peak periods. These added delays impose higher costs on 
drivers and other vehicle occupants in the form of increased travel 
time and operating expenses, increased costs associated with traffic 
accidents, and increased traffic noise. Because drivers do not take 
these added costs into account in deciding when and where to travel, 
they must be accounted for separately as a cost of the added driving 
associated with the rebound effect.
    EPA and NHTSA rely on estimates of congestion, accident, and noise 
costs caused by pickup trucks and vans, single unit trucks, buses, and 
combination tractors developed by the Federal Highway Administration to 
estimate the increased external costs caused by added driving due to 
the rebound effect.\544\ The Federal Highway Administration (FHWA) 
estimates are intended to measure the increases in costs from added 
congestion, property damages and injuries in traffic accidents, and 
noise levels caused by various types of trucks that are borne by 
persons other than their drivers (or ``marginal'' external costs). EPA 
and NHTSA employed estimates from this source previously in the 
analysis accompanying the light-Duty 2012-16 MY vehicle rule. The 
agencies continue to find them appropriate for this analysis after 
reviewing the procedures used by FHWA to develop them and considering 
other available estimates of these values.
---------------------------------------------------------------------------

    \544\ These estimates were developed by FHWA for use in its 1997 
Federal Highway Cost Allocation Study; See http://www.fhwa.dot.gov/policy/hcas/final/index.htm (last accessed July 21, 2010).
---------------------------------------------------------------------------

    FHWA's congestion cost estimates for trucks, which are weighted 
averages based on the estimated fractions of peak and off-peak freeway 
travel for each class of trucks, already account for the fact that 
trucks make up a smaller fraction of peak period traffic on congested 
roads because they try to avoid peak periods when possible. FHWA's 
congestion cost estimates focus on freeways because non-freeway effects 
are less serious due to lower traffic volumes and opportunities to re-
route around the congestion. The agencies, however, applied the 
congestion cost to the overall VMT increase, though the fraction of VMT 
on each road type used in MOVES range from 27 to 29 percent of the 
vehicle miles on freeways for vocational vehicles and 53 percent for 
combination tractors. The results of this analysis potentially 
overestimate the costs and provide a conservative estimate.
    The agencies are using FHWA's ``Middle'' estimates for marginal 
congestion, accident, and noise costs caused by increased travel from 
trucks. This approach is consistent with the current methodology used 
in the Light-Duty GHG rulemaking analysis. These costs are multiplied 
by the annual increases in vehicle miles travelled from the positive 
rebound effect to yield the estimated cost increases resulting from 
increased congestion, accidents, and noise during each future year. The 
values the agencies used to calculate these increased costs are 
included in Table VIII-24.

                          Table VIII-24--Noise, Accident, and Congestion Costs per Mile
                                                     [2009$]
----------------------------------------------------------------------------------------------------------------
                                                              Pickup trucks      Vocational        Combination
                      External costs                          and vans  ($/     vehicles  ($/     tractors  ($/
                                                                  VMT)              VMT)              VMT)
----------------------------------------------------------------------------------------------------------------
Congestion................................................            $0.049            $0.111            $0.108

[[Page 57342]]

 
Accidents.................................................             0.027             0.019             0.022
Noise.....................................................             0.001             0.009             0.020
----------------------------------------------------------------------------------------------------------------

    In aggregate, the increased costs due to noise, accidents, and 
congestion from the additional truck driving are presented in Table 
VIII-25.

                              Table VIII-25: Accident, Noise, and Congestion Costs
                                                [Millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                            Pickup trucks      Vocational        Combination
                  Year                        and vans          vehicles          tractors         Total costs
----------------------------------------------------------------------------------------------------------------
2012....................................                $0                $0                $0                $0
2013....................................                 0                 0                 0                 0
2014....................................                 8                21                18                46
2015....................................                15                38                31                84
2016....................................                22                55                43               120
2017....................................                29                71                54               153
2018....................................                36                85                64               186
2020....................................                51               112                83               246
2030....................................               105               195               138               437
2040....................................               130               256               166               551
2050....................................               148               298               191               638
NPV, 3%.................................             1,818             3,620             2,492             7,929
NPV, 7%.................................               832             1,680             1,184             3,695
----------------------------------------------------------------------------------------------------------------

(2) Savings Due to Reduced Refueling Time
    Reducing the fuel consumption of heavy-duty trucks may either 
increase their driving range before they require refueling, or motivate 
truck purchasers to buy, and manufacturers to offer, smaller fuel 
tanks. Keeping the fuel tank the same size allows truck operators to 
reduce the frequency with which drivers typically refuel their 
vehicles; it thus extends the upper limit of the range they can travel 
before requiring refueling. Alternatively, if purchasers and 
manufacturers respond to improved fuel efficiency by reducing the size 
of fuel tanks to maintain a constant driving range, the smaller tank 
will require less time in actual refueling.
    Because refueling time represents a time cost of truck operation, 
these time savings should be incorporated into truck purchasers' 
decisions over how much fuel-saving technology they want in their 
vehicles. The savings calculated here thus raise the same questions 
discussed in Preamble VIII.A and RIA Section 9.1 does the apparent 
existence of these savings reflect failures in the market for fuel 
efficiency, or does it reflect costs not addressed in this analysis? 
The response to these questions could vary across truck segment. See 
those sections for further analysis of this question.
    This analysis estimates the reduction in the annual time spent 
filling the fuel tank; this reduced time could come either from fewer 
refueling events, if the fuel tank stays the same size, or less time 
spent during each refueling event, if the fuel tank is made 
proportionately smaller. The refueling savings are calculated as the 
savings in the amount of time that would have been necessary to pump 
the fuel. The calculation does not include time spent searching for a 
fuel station or other time spent at the station; it is assumed that the 
time savings occur only during refueling. The value of the time saved 
is estimated at the hourly rate recommended for truck operators ($22.36 
in 2009 dollars) in DOT guidance for valuing time savings.\545\
---------------------------------------------------------------------------

    \545\ U.S. Department of Transportation, ``Revised Departmental 
Guidance for Valuation of Travel Time in Economic Analysis,'' 
February 11, 2003, Table 4 (which shows a value of $18.10 in 2000 
dollars); available at http://ostpxweb.dot.gov/policy/Data/VOTrevision1_2-11-03.pdf (last accessed September 9, 2010).
---------------------------------------------------------------------------

    The refueling savings include the increased fuel consumption 
resulting from additional mileage associated with the rebound effect. 
However, the estimate of the rebound effect does not account for any 
reduction in net operating costs from lower refueling time. As 
discussed earlier, the rebound effect should be a measure of the change 
in VMT with respect to the net change in overall operating costs. 
Ideally, changes in refueling time would factor into this calculation, 
although the effect is expected to be minor because refueling time 
savings are small relative to the value of reduced fuel expenditures.
    The details of this calculation are discussed in the RIA Chapter 
9.3.2. The savings associated with reduced refueling time for a truck 
of each type throughout its lifetime are shown in Table VIII-26. The 
aggregate savings associated with reduced refueling time are shown in 
Table VIII-27 for vehicles sold in 2014 through 2050.

[[Page 57343]]

                   Table VIII-26--Lifetime Refueling Savings for a 2018 MY Truck of Each Type
                                                     [2009$]
----------------------------------------------------------------------------------------------------------------
                                                              Pickup trucks      Vocational        Combination
                                                                and vans          vehicles           tractor
----------------------------------------------------------------------------------------------------------------
3% Discount Rate..........................................               $31               $34              $341
7% Discount Rate..........................................                19                22               223
----------------------------------------------------------------------------------------------------------------

                                     Table VIII-27--Annual Refueling Savings
                                                [Millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                            Pickup trucks      Vocational        Combination
                  Year                        and vans          vehicles           tractor            Total
----------------------------------------------------------------------------------------------------------------
2012....................................              $0.0              $0.0              $0.0              $0.0
2013....................................               0.0               0.0               0.0               0.0
2014....................................               0.2               1.4               8.0               9.6
2015....................................               0.5               2.6              14.3              17.3
2016....................................               1.3               3.8              19.6              24.6
2017....................................               2.7               6.2              26.7              35.6
2018....................................               5.2               8.5              33.8              47.5
2020....................................              10.5              12.7              46.2              69.3
2030....................................              32.6              25.8              82.9             141
2040....................................              43.4              35.1             100.5             179
2050....................................              50.1              41.3             116.1             207
NPV, 3%.................................             541               468             1,467             2,476
NPV, 7%.................................             231               210               685             1,126
----------------------------------------------------------------------------------------------------------------

K. The Effect of Safety Standards and Voluntary Safety Improvements on 
Vehicle Weight

    Safety standards developed by NHTSA in previous rulemakings may 
make compliance with the fuel efficiency and CO2 emissions 
standards more difficult or may reduce the projected benefits of the 
program. The primary way that safety regulations can impact fuel 
efficiency and CO2 emissions is through increased vehicle 
weight, which reduces the fuel efficiency (and thus increases the 
CO2 emissions) of the vehicle. Using MY 2010 as a baseline, 
this section discusses the effects of other government regulations on 
MYs 2014-2016 medium and heavy-duty vehicle fuel efficiency and 
CO2 emissions. At this time, no known safety standards will 
affect new models in MY 2017 or 2018. NHTSA's estimates are based on 
cost and weight tear-down studies of a few vehicles and cannot possibly 
cover all the variations in the manufacturers' fleets. NHTSA also 
requested, and various manufacturers provided, confidential estimates 
of increases in weight resulting from safety improvements. Those 
increases are shown in subsequent tables.
    We have broken down our analysis of the impact of safety standards 
that might affect the MYs 2014-2016 fleets into three parts: (1) Those 
NHTSA final rules with known effective dates, (2) proposed rules or 
soon-to-be proposed rules by NHTSA with or without final effective 
dates, and (3) currently voluntary safety improvements planned by the 
manufacturers.
(1) Weight Impacts of Required Safety Standards
    NHTSA has undertaken several rulemakings in which several standards 
would become effective for medium- and heavy-duty (MD/HD) vehicles 
between MY 2014 and MY 2016. We will examine the potential impact on 
MD/HD vehicle weights for MYs 2014-2016 using MY 2010 as a baseline.

 FMVSS 119, Heavy Truck Tires Endurance and High Speed Tests.
 FMVSS 121, Air Brake Systems Stopping Distance.
 FMVSS 214, Motor Coach Lap/Shoulder Belts.
 MD/HD Vehicle Electronic Stability Control Systems.
(a) FMVSS 119, Heavy Truck Tires Endurance and High Speed Tests
    NHTSA tentatively determined that the FMVSS No. 119 performance 
tests developed in 1973 should be updated to reflect the increased 
operational speeds and duration of truck tires in commercial service. A 
Notice of Proposed Rulemaking (NPRM) was issued December 7, 2010 (75 FR 
60036). It proposed to increase significantly the stringency of the 
endurance test and to add a new high speed test. The data in the large 
truck crash causation study (LTCCS) that preceded that NPRM found that 
J and L load range tires were having proportionately more problems than 
the other sizes and the agency's test results indicate that H, J, and L 
load range tires are more likely to fail the proposed requirements 
among the targeted F, G, H, J and L load range tires.\546\ To address 
these problems, the H and J load range tires could potentially use 
improved rubber compounds, which would add no weight to the tires, to 
reduce heat retention and improve the durability of the tires. The L 
load range tires, in contrast, appear to need to use high tensile 
strength steel chords in the tire bead, carcass and belt areas, which 
would enable a weight reduction with no strength penalties. Thus, if 
the update to FMVSS No. 119 was finalized, we anticipate no change in 
weight for H and J load range tires and a small reduction in weight for 
L load range tires. This proposal could become a final rule with an 
effective date of MY 2016.
---------------------------------------------------------------------------

    \546\ ``Preliminary Regulatory Impact Analysis, FMVSS No. 119, 
New Pneumatic Tires for Motor Vehicles with a GVWR of More Than 
4,536 kg (10,000 pounds), June 2010.
---------------------------------------------------------------------------

(b) FMVSS No. 121, Airbrake Systems Stopping Distance
    FMVSS No. 121 contains performance and equipment requirements for 
braking systems on vehicles with air brake systems. The most recent 
major final rule affecting FMVSS No. 121 was published on July 27, 
2009, and became effective on November 24, 2009 (MY 2009). The final 
rule requires the vast

[[Page 57344]]

majority of new heavy truck tractors (approximately 99 percent of the 
fleet) to achieve a 30 percent reduction in stopping distance compared 
to currently required levels. Three-axle tractors with a gross vehicle 
weight rating (GVWR) of 59,600 pounds or less must meet the reduced 
stopping distance requirements by August 1, 2011 (MY 2011), while two-
axle tractors and tractors with a GVWR above 59,600 pounds must meet 
the reduced stopping distance requirements by the later date of August 
1, 2013 (MY 2013). NHTSA determined that there are several brake 
systems that can meet the requirements established in the final rule, 
including installation of larger S-cam drum brakes or disc brake 
systems at all positions, or hybrid disc and larger rear S-cam drum 
brake systems.
    According to data provided by a manufacturer (Bendix) in response 
to the NPRM, the heaviest drum brakes weigh more than the lightest disc 
brakes, while the heaviest disc brakes weigh more than the lightest 
drum brakes. For a three-axle tractor equipped with all disc brakes, 
then, the total weight could increase by 212 pounds or could decrease 
by 134 pounds compared to an all-drum-braked tractor, depending on 
which disc or drum brakes are used for comparison. The improved brakes 
may add a small amount of weight to the affected vehicles for MYs 2014-
2016, resulting in a slight increase in fuel consumption.
(c) FMVSS No. 208, Motorcoach Lap/Shoulder Belts
    NHTSA is proposing lap/shoulder belts for all motorcoach seats. 
About 2,000 motorcoaches are sold per year in the United States. Based 
on preliminary results from the agency's cost/weight teardown studies 
of motor coach seats,\547\ NHTSA estimates that the weight added by 3-
point lap/shoulder belts ranges from 5.96 to 9.95 pounds per 2-person 
seat. This is the weight only of the seat belt assembly itself, and 
does not include changing the design of the seat, reinforcing the 
floor, walls or other areas of the motor coach. Few current production 
motor coaches have been installed with lap/shoulder belts on their 
seats, and the number of vehicles with these belts already installed 
could be negligible. Assuming a 54 passenger motor coach, the added 
weight for the 3-point lap/shoulder belt assembly would be in the range 
of 161 to 269 pounds (27 * (5.96 to 9.95)) per vehicle. This proposal 
could become a final rule with an effective date of MY 2016.
---------------------------------------------------------------------------

    \547\ Cost and Weight Analysis of Two Motorcoach Seating 
Systems: One With and One Without Three-Point Lap/Shoulder Belt 
Restraints, Ludtke and Associates, July 2010.
---------------------------------------------------------------------------

(d) Electronic Stability Control Systems (ESC) for Medium- and Heavy-
Duty (MD/HD) Vehicles
    The purpose of an ESC system for MD/HD vehicles is to reduce 
crashes caused by rollover or by directional loss-of-control. ESC 
monitors a vehicle's rollover threshold and lateral stability using 
vehicle speed, wheel speed, steering wheel angle, lateral acceleration, 
side slip and yaw rate data and upon sensing an impending rollover or 
loss of directional control situation automatically reduces engine 
throttle and applies braking forces to individual wheels or sets of 
wheel to slow the vehicle down and regain directional control. ESC is 
not currently required in MD/HD vehicles, but could be proposed to be 
required in these vehicles by NHTSA. FMVSS No. 105, Hydraulic and 
electric brake systems, requires multipurpose passenger vehicles, 
trucks and buses with a GVWR greater than 4,536 kg (10,000 pounds) to 
be equipped with an antilock brake system (ABS). All MD/HD vehicles 
having a GVWR of more than 10,000 pounds, are required to have ABS 
installed by that standard.
    In addition to the existing ABS functionality, ESC requires sensors 
including a yaw rate sensor, lateral acceleration sensor, steering 
angle sensor and brake pressure sensor along with a brake solenoid 
valve. According to data provided by Meritor WABCO, the weight of an 
ESC system for the model 4S4M tractor is estimated to be around 55.5 
pounds, and the weight of the ABS only is estimated to be 45.5 pounds. 
Thus, we estimate the added weight for the ESC for the vehicle to be 10 
(55.5-45.5) pounds.
(2) Summary--Overview of Anticipated Weight Increases
    Table VIII-28 summarizes estimates made by NHTSA regarding the 
weight added by the above discussed standards or likely rulemakings. 
NHTSA estimates that weight additions required by final rules and 
likely NHTSA regulations effective in MY 2016 compared to the MY 2010 
fleet will increase motor coach vehicle weight by 171 to 279 pounds and 
will increase other heavy-duty truck weights by 10 pounds.

   Table VIII-28--Weight Additions Due to Final Rules or Likely NHTSA
      Regulations: Comparing MY 2016 to the MY 2010 Baseline Fleet
------------------------------------------------------------------------
                                       Added weight in   Added weight in
            Standard No.                pounds MD/HD     kilograms MD/HD
                                           vehicle           vehicle
------------------------------------------------------------------------
119.................................                 0                 0
121.................................             \a\ 0             \a\ 0
208 Motor coaches only..............           161-269            73-122
MD/HD Vehicle Electronic Stability                  10               4.5
 Control Systems....................
Total Motor coaches.................           171-279        77.5-126.5
Total All other MD/HD vehicles......                10               4.5
------------------------------------------------------------------------
Note:
\a\ NHTSA's final rule on Air Brakes, docket NHTSA-2009-0083, dated July
  27, 2009, concluded that a small amount of weight would be added to
  the brake systems but a weight value was not provided.

[[Page 57345]]

(3) Effects of Vehicle Mass Reduction on Safety
    NHTSA and EPA have been considering the effect of vehicle weight on 
vehicle safety for the past several years in the context of our joint 
rulemaking for light-duty vehicle CAFE and GHG standards, consistent 
with NHTSA's long-standing consideration of safety effects in setting 
CAFE standards. Combining all modes of impact, the latest analysis by 
NHTSA for the light-duty 2012-2016 MY vehicle rule \548\ found that 
reducing the weight of the heavier light trucks (LT > 3,870) had a 
positive overall effect on safety, reducing societal fatalities.
---------------------------------------------------------------------------

    \548\ ``Final Regulatory Impact Analysis, Corporate Average Fuel 
Economy for MY 2012--MY 2016 Passenger Cars and Light Trucks'', 
NHTSA, March 2010, (Docket No. NHTSA-2009-0059-0344.1).
---------------------------------------------------------------------------

    In the context of the current rulemaking for HD fuel consumption 
and GHG standards, one would expect that reducing the weight of medium-
duty trucks similarly would, if anything, have a positive impact on 
safety. However, given the large difference in weight between light-
duty vehicles and medium-duty trucks, and even larger difference 
between light-duty vehicles and heavy-duty vehicles with loads, the 
agencies believe that the impact of weight reductions of medium- and 
heavy-duty trucks would not have a noticeable impact on safety for any 
of these classes of vehicles.
    However, the agencies recognize that it is important to conduct 
further study and research into the interaction of mass, size and 
safety to assist future rulemakings, and we expect that the 
collaborative interagency work currently on-going to address this issue 
for the light-duty vehicle context may also be able to inform our 
evaluation of safety effects for the final HD program. We intend to 
continue monitoring this issue going forward, and may take steps in a 
future rulemaking if it appears that the MD/HD fuel efficiency and GHG 
standards have unforeseen safety consequences. The American Chemistry 
Council stated in comments to the agencies that plastics and plastic 
composite materials provide a new way to lighten vehicles while 
maintaining passenger safety. They added that properties of plastics 
including strength to weight ratio, energy absorption, and flexible 
design make these materials well suited for the manufacture of medium- 
and heavy-duty vehicles. They submitted supporting analyses with their 
comments. The National School Transportation Association stated that 
added structural integrity requirements increase weight of school 
buses, and thus decrease fuel economy. They asked that if there are 
safety and fuel economy trade-offs, manufacturers should be able to 
receive a waiver from the regulation's requirements. Since no weight 
reduction is required for school buses--or any other vocational 
vehicle--the agencies do not believe this is an issue with the current 
regulation.

L. Summary of Costs and Benefits

    In this section, the agencies present a summary of costs, benefits, 
and net benefits of the HD National program.
    Table VIII-29 shows the estimated annual monetized costs of the 
final program for the indicated calendar years. The table also shows 
the net present values of those costs for the calendar years 2012-2050 
using both 3 percent and 7 percent discount rates.\549\ Table VIII-30 
shows the estimated annual monetized fuel savings of the final program. 
The table also shows the net present values of those fuel savings for 
the same calendar years using both 3 percent and 7 percent discount 
rates. In this table, the aggregate value of fuel savings is calculated 
using pre-tax fuel prices since savings in fuel taxes do not represent 
a reduction in the value of economic resources utilized in producing 
and consuming fuel. Note that fuel savings shown here result from 
reductions in fleet-wide fuel use. Thus, they grow over time as an 
increasing fraction of the fleet meets the 2018 standards.
---------------------------------------------------------------------------

    \549\ For the estimation of the stream of costs and benefits, we 
assume that after implementation of the final MY 2014-2017 
standards, the 2017 standards apply to each year out to 2050.

                                              Table VIII-29--Estimated Monetized Costs of the Final Program
                                                                   [Millions, 2009$] a
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                     NPV, Years 2012-   NPV, Years 2012-
                                                                       2020        2030        2040        2050     2050, 3% discount  2050, 7% discount
                                                                                                                           rate               rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
Technology Costs..................................................     $2,000      $2,200      $2,700      $3,300            $47,400            $24,700
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
\a\ Technology costs for separate truck segments can be found in Section VIII.B.1.

                                               Table VIII-30--Estimated Fuel Savings of the Final Program
                                                                   [Millions, 2009$] a
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                     NPV, Years 2012-   NPV, Years 2012-
                                                                       2020        2030        2040        2050     2050, 3% discount  2050, 7% discount
                                                                                                                           rate               rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fuel Savings (pre-tax)............................................     $9,600     $20,600     $28,000     $36,500           $375,300           $166,500
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
\a\ Fuel savings for separate truck segments can be found in Section VIII.B.1.

    Table VIII-31 presents estimated annual monetized benefits for the 
indicated calendar years. The table also shows the net present values 
of those benefits for the calendar years 2012-2050 using both 3 percent 
and 7 percent discount rates. The table shows the benefits of reduced 
CO2 emissions--and consequently the annual quantified 
benefits (i.e., total benefits)--for each of four SCC values estimated 
by the interagency working group. As discussed in the RIA Section 9.4, 
there are some limitations to the SCC analysis, including the 
incomplete way in which the integrated assessment models capture 
catastrophic and non-catastrophic impacts, their incomplete

[[Page 57346]]

treatment of adaptation and technological change, uncertainty in the 
extrapolation of damages to high temperatures, and assumptions 
regarding risk aversion.
    In addition, these monetized GHG benefits exclude the value of net 
reductions in non-CO2 GHG emissions (CH4, 
N2O, HFC) expected under this action. Although EPA has not 
monetized the benefits of reductions in non-CO2 GHGs, the 
value of these reductions should not be interpreted as zero. Rather, 
the net reductions in non-CO2 GHGs will contribute to this 
program's climate benefits, as explained in Section VI.D.

                       Table VIII-31--Monetized Benefits Associated With the Final Program
                                                [Millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                                                              NPV, Years 2012-  NPV, Years 2012-
                                                                                  2050, 3%          2050, 7%
                                     2020       2030       2040       2050      discount rate     discount rate
                                                                                     \a\               \a\
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at each assumed SCC value \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................       $300       $700     $1,200     $1,700            $9,000            $9,000
3% (avg SCC)....................      1,000      2,500      3,600      4,800            46,100            46,100
2.5% (avg SCC)..................      1,600      3,800      5,400      7,000            78,000            78,000
3% (95th percentile)............      3,100      7,500     11,100     14,600           140,400           140,400
Energy Security Impacts (price          500      1,100      1,500      1,700            19,800             8,800
 shock).........................
Accidents, Congestion, Noise \f\       -200       -400       -600       -600            -7,900            -3,700
Refueling Savings...............        100        100        200        200             2,500             1,100
Non-GHG Impacts c d.............          B      2,800      2,800      2,800            25,300             9,100
Non-CO2 GHG Impacts \e\.........        n/a        n/a        n/a        n/a               n/a               n/a
----------------------------------------------------------------------------------------------------------------
                               Total Annual Benefits at each assumed SCC value \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................        700      4,300      5,100      5,800            48,700            24,300
3% (avg SCC)....................      1,400      6,100      7,500      8,900            85,800            61,400
2.5% (avg SCC)..................      2,000      7,400      9,300     11,100           117,700            93,300
3% (95th percentile)............      3,500     11,100     15,000     18,700           180,100           155,700
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. See Section VIII.F.
\c\ Note that ``B'' indicates unquantified criteria pollutant benefits in the year 2020. For the analysis of the
  final program, we only modeled the rule's PM2.5- and ozone-related impacts in the calendar year 2030. For the
  purposes of estimating a stream of future-year criteria pollutant benefits, we assume that the benefits out to
  2050 are equal to, and no less than, those modeled in 2030 as reflected by the stream of estimated future
  emission reductions. The NPV of criteria pollutant-related benefits should therefore be considered a
  conservative estimate of the potential benefits associated with the final program.
\d\ Non-GHG-related health and welfare impacts (related to PM2.5 and ozone exposure) range between $1,300 and
  $4,200 million in 2030, 2040, and 2050. $2,800 was chosen as the mid-point of this range for the purposes of
  estimating total benefits across all monetized categories.
\e\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions
  expected under this program (See RIA Chapter 5). Although EPA has not monetized changes in non-CO2 GHGs, the
  value of any increases or reductions should not be interpreted as zero.
\f\ Negative sign represents an increase in Accidents, Congestion, and Noise.

    Table VIII-32 presents estimated annual net benefits for the 
indicated calendar years. The table also shows the net present values 
of those net benefits for the calendar years 2012-2050 using both 3 
percent and 7 percent discount rates. The table includes the benefits 
of reduced CO2 emissions (and consequently the annual net 
benefits) for each of four SCC values considered by EPA.

                                         Table VIII-32--Monetized Net Benefits Associated With the Final Program
                                                                    [Millions, 2009$]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               2020            2030            2040            2050         NPV, 3% \a\     NPV, 7% \a\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Technology Costs........................................          $2,000          $2,200          $2,700          $3,300         $47,400         $24,700
Fuel Savings............................................           9,600          20,600          28,000          36,500         375,300         166,500
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Total Annual Benefits at each assumed SCC value \b\
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC)............................................             700           4,300           5,100           5,800          48,700          24,300
3% (avg SCC)............................................           1,400           6,100           7,500           8,900          85,800          61,400
2.5% (avg SCC)..........................................           2,000           7,400           9,300          11,100         117,700          93,300
3% (95th percentile)....................................           3,500          11,100          15,000          18,700         180,100         155,700
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Monetized Net Benefits at each assumed SCC value \c\
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC)............................................           8,300          22,700          30,400          39,000         376,600         166,100
3% (avg SCC)............................................           9,000          24,500          32,800          42,100         413,700         203,200

[[Page 57347]]

 
2.5% (avg SCC)..........................................           9,600          25,800          34,600          44,300         445,600         235,100
3% (95th percentile)....................................          11,100          29,500          40,300          51,900         508,000         297,500
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount rate used to discount the value of
  damages from future emissions (SCC at 5, 3, 2.5 percent) is used to calculate net present value of SCC for internal consistency. Refer to the SCC TSD
  for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC estimates range as follows: for Average SCC at
  5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at 2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also
  presents these SCC estimates.
\c\ Net Benefits equal Fuel Savings minus Technology Costs plus Benefits.

    EPA also conducted a separate analysis of the total benefits over 
the model year lifetimes of the 2014 through 2018 model year trucks. In 
contrast to the calendar year analysis presented above in Table VIII-29 
through Table VIII-32, the model year lifetime analysis below shows the 
impacts of the final program on vehicles produced during each of the 
model years 2014 through 2018 over the course of their expected 
lifetimes. The net societal benefits over the full lifetimes of 
vehicles produced during each of the five model years from 2014 through 
2018 are shown in Table VIII-33 and Table VIII-34 at both 3 percent and 
7 percent discount rates, respectively.

    Table VIII-33--Monetized Technology Costs, Fuel Savings, Benefits, and Net Benefits Associated With the Lifetimes of 2014-2018 Model Year Trucks
                                                           [Millions, 2009$; 3% Discount Rate]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         2014 MY         2015 MY         2016 MY         2017 MY         2018 MY     Sum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Technology Costs...................................................          $1,600          $1,400          $1,500          $1,600          $2,000  $8,
                                                                                                                                                     100
Fuel Savings (pre-tax).............................................           9,300           8,300           8,100          11,500          12,900  50,
                                                                                                                                                     100
Energy Security Impacts (price shock)..............................             500             400             400             600             700  2,7
                                                                                                                                                     00
Accidents, Congestion, Noise \e\...................................            -300            -300            -300            -300            -300  -1,
                                                                                                                                                     500
Refueling Savings..................................................              60              60              60              80             100  400
Non-CO2 GHG Impacts and Non-GHG Impactsc d.........................             n/a             n/a             n/a             n/a             n/a  n/a
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Reduced CO2 Emissions at each assumed SCC value a b
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC).......................................................             200             200             200             300             300  1,2
                                                                                                                                                     00
3% (avg SCC).......................................................           1,100             900             900           1,300           1,500  5,7
                                                                                                                                                     00
2.5% (avg SCC).....................................................           1,800           1,600           1,500           2,100           2,400  9,4
                                                                                                                                                     00
3% (95th percentile)...............................................           3,300           2,900           2,800           4,000           4,500  17,
                                                                                                                                                     000
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Monetized Net Benefits at each assumed SCC value a,b
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC).......................................................           8,200           7,300           7,000          10,600          11,700  44,
                                                                                                                                                     800
3% (avg SCC).......................................................           9,100           8,000           7,700          11,600          12,900  49,
                                                                                                                                                     300
2.5% (avg SCC).....................................................           9,800           8,700           8,300          12,400          13,800  53,
                                                                                                                                                     000
3% (95th percentile)...............................................          11,300          10,000           9,600          14,300          15,900  60,
                                                                                                                                                     600
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount rate used to discount the value of
  damages from future emissions (SCC at 5, 3, 2.5 percent) is used to calculate net present value of SCC for internal consistency. Refer to the SCC TSD
  for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC estimates range as follows: for Average SCC at
  5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at 2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also
  presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions expected under this action (See RIA
  Chapter 5). Although EPA has not monetized changes in non-CO2 GHGs, the value of any increases or reductions should not be interpreted as zero.
\d\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not estimated for this analysis.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

    Table VIII-34--Monetized Technology Costs, Fuel Savings, Benefits, and Net Benefits Associated With the Lifetimes of 2014-2018 Model Year Trucks
                                                           [Millions, 2009$; 7% Discount Rate]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              2014 MY         2015 MY         2016 MY         2017 MY         2018 MY           Sum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Technology Costs........................................          $1,600          $1,400          $1,500          $1,600          $2,000          $8,100
Fuel Savings (pre-tax)..................................           6,900           5,900           5,600           7,600           8,300          34,400
Energy Security Impacts (price shock)...................             400             300             300             400             400           1,800
Accidents, Congestion, Noise \e\........................            -200            -200            -200            -200            -200          -1,000

[[Page 57348]]

 
Refueling Savings.......................................              50              40              40              60              60             200
Non-CO2 GHG Impacts and Non-GHG Impacts c d.............             n/a             n/a             n/a             n/a             n/a             n/a
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Reduced CO2 Emissions at each assumed SCC value a b
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC)............................................             200             200             200             300             300           1,200
3% (avg SCC)............................................           1,100             900             900           1,300           1,500           5,700
2.5% (avg SCC)..........................................           1,800           1,600           1,500           2,100           2,400           9,400
3% (95th percentile)....................................           3,300           2,900           2,800           4,000           4,500          17,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Monetized Net Benefits at each assumed SCC valuea b
--------------------------------------------------------------------------------------------------------------------------------------------------------
5% (avg SCC)............................................           5,800           4,800           4,400           6,600           6,900          28,500
3% (avg SCC)............................................           6,700           5,500           5,100           7,600           8,100          33,000
2.5% (avg SCC)..........................................           7,400           6,200           5,700           8,400           9,000          36,700
3% (95th percentile)....................................           8,900           7,500           7,000          10,300          11,100          44,300
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount rate used to discount the value of
  damages from future emissions (SCC at 5, 3, 2.5 percent) is used to calculate net present value of SCC for internal consistency. Refer to the SCC TSD
  for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC estimates range as follows: for Average SCC at
  5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at 2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also
  presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions expected under this action (See RIA
  chapter 5). Although EPA has not monetized changes in non-CO2 GHGs, the value of any increases or reductions should not be interpreted as zero.
\d\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not estimated for this analysis.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

    Table VIII-35 and Table VIII-36 show similar model year estimates 
to those provided above in Table VIII-33 and Table VIII-34, but reflect 
specific differences in the NHTSA HD program over the 3 mandatory model 
years of that program. These include no HD diesel engine impacts prior 
to MY 2017, assumption of the NHTSA phase-in schedule for HD pickup 
trucks and vans which achieves 3 year phase-in stability (67%-67%-67%-
100% in MY 2016-2019 respectively), the inclusion of combination 
tractors from MY 2016 forward, and the exclusion of RVs, which are not 
regulated by NHTSA.

     Table VIII-35--Monetized Technology Costs, Fuel Savings, Benefits, and Net Benefits Associated With the
                                    Lifetimes of 2016-2018 Model Year Trucks
                                       [Millions, 2009$; 3% Discount Rate]
----------------------------------------------------------------------------------------------------------------
                                                      2016 MY         2017 MY         2018 MY           Sum
----------------------------------------------------------------------------------------------------------------
Technology Costs................................          $1,500          $1,600          $1,700          $5,200
Fuel Savings (pre-tax)..........................           5,500          10,900          11,500          27,900
Energy Security Impacts (price shock)...........             300             600             600           1,500
Accidents, Congestion, Noise \e\................            -300            -300            -300            -900
Refueling Savings...............................              40              80              80             200
Non-CO2 GHG Impacts and Non-GHG Impacts c d.....             n/a             n/a             n/a             n/a
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at each assumed SCC value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................................             100             300             300             700
3% (avg SCC)....................................             600           1,200           1,300           3,100
2.5% (avg SCC)..................................           1,000           2,000           2,200           5,200
3% (95th percentile)............................           1,900           3,800           4,000           9,700
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at each assumed SCC value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................................           4,100          10,000          10,500          24,200
3% (avg SCC)....................................           4,600          10,900          11,500          26,600
2.5% (avg SCC)..................................           5,000          11,700          12,400          28,700
3% (95th percentile)............................           5,900          13,500          14,200          33,200
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.

[[Page 57349]]

 
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions
  expected under this program (See RIA Chapter 5). Although EPA has not monetized changes in non-CO2 GHGs, the
  value of any increases or reductions should not be interpreted as zero.
\d\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

     Table VIII-36--Monetized Technology Costs, Fuel Savings, Benefits, and Net Benefits Associated With the
                                    Lifetimes of 2016-2018 Model Year Trucks
                                       [Millions, 2009$; 7% Discount Rate]
----------------------------------------------------------------------------------------------------------------
                                                      2016 MY         2017 MY         2018 MY           Sum
----------------------------------------------------------------------------------------------------------------
Technology Costs................................          $1,500          $1,600          $1,700          $5,200
Fuel Savings (pre-tax)..........................           3,800           7,200           7,300          18,300
Energy Security Impacts (price shock)...........             200             400             400           1,000
Accidents, Congestion, Noise \e\................            -200            -200            -200            -600
Refueling Savings...............................              30              50              50             130
Non-CO2 GHG Impacts and Non-GHG Impacts c d.....             n/a             n/a             n/a             n/a
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at each assumed SCC value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................................             100             300             300             700
3% (avg SCC)....................................             600           1,200           1,300           3,100
2.5% (avg SCC)..................................           1,000           2,000           2,200           5,200
3% (95th percentile)............................           1,900           3,800           4,000           9,700
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at each assumed SCC value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................................           2,400           6,200           6,200          14,300
3% (avg SCC)....................................           2,900           7,100           7,200          16,700
2.5% (avg SCC)..................................           3,300           7,900           8,100          18,800
3% (95th percentile)............................           4,200           9,700           9,900          23,300
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions
  expected under this program (See RIA Chapter 5). Although EPA has not monetized changes in non-CO2 GHGs, the
  value of any increases or reductions should not be interpreted as zero.
\d\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

M. Employment Impacts

(1) Introduction
    Although analysis of employment impacts is not part of a cost-
benefit analysis (except to the extent that labor costs contribute to 
costs), employment impacts of federal rules are of particular concern 
in the current economic climate of sizeable unemployment. The recently 
issued Executive Order 13563, ``Improving Regulation and Regulatory 
Review'' (January 18, 2011), states, ``Our regulatory system must 
protect public health, welfare, safety, and our environment while 
promoting economic growth, innovation, competitiveness, and job 
creation'' (emphasis added). Although EPA and NHTSA did not undertake 
an employment analysis of the proposed rules, several commenters 
suggested that we undertake an employment analysis for the final 
rulemaking. Consistent with Executive order 13563, we have provided a 
discussion of the potential employment impacts of the Heavy-Duty 
National Program.
    In recent rulemakings, EPA has generally focused its employment 
analysis on the regulated sector and the suppliers of pollution 
abatement equipment. However, in this action, the agencies are offering 
qualitative assessment for related industries of interest. For the 
regulated sector, the agencies rely on Morgenstern et al. for 
guidance.\550\ Our general conclusion is that employment impacts in the 
regulated sector (truck and engine manufacturing) and the parts sectors 
depend on a combination of factors, some of which are positive, and 
some of which can be positive or negative. In the related industries, 
the analysis concludes that effects on employment in the transport and 
shipping sectors are ambiguous; the fuel supplying sectors may face 
reduced employment; and there may be increased general employment due 
to reduction in costs that may be passed along to the transport 
industry and thus to the public. Because measuring employment effects 
depends on a variety of inputs and assumptions, some of which are known 
with more certainty than others, and because we did not include an 
employment analysis in the NPRM and provide opportunity for public 
comment on the methods, we here present a qualitative discussion. 
Because the discussion is qualitative, we do not sum the net effects on 
employment. We also note that the employment effects may be different 
in the immediate implementation phase than in the ongoing compliance 
phase; this analysis

[[Page 57350]]

focuses on the longer-term effects rather than the immediate effects.
---------------------------------------------------------------------------

    \550\ Morgenstern, Richard D., William A. Pizer, and Jhih-Shyang 
Shih. ``Jobs Versus the Environment: An Industry-Level 
Perspective.'' Journal of Environmental Economics and Management 43 
(2002): 412-436.
---------------------------------------------------------------------------

    When the economy is at full employment, an environmental regulation 
is unlikely to have much impact on net overall U.S. employment; 
instead, labor would primarily be shifted from one sector to another. 
These shifts in employment impose an opportunity cost on society, 
approximated by the wages of the employees, as regulation diverts 
workers from other activities in the economy.\551\ In this situation, 
any effects on net employment are likely to be transitory as workers 
change jobs. (For example, some workers may need to be retrained or 
require time to search for new jobs, while shortages in some sectors or 
regions could bid up wages to attract workers).\552\
---------------------------------------------------------------------------

    \551\ Schmalensee, Richard, and Robert N. Stavins. ``A Guide to 
Economic and Policy Analysis of EPA's Transport Rule.'' White paper 
commissioned by Excelon Corporation, March 2011.
    \552\ Although the employment level would not change 
substantially, there would be costs to the workers associated with 
shifting from one activity to another. Jacobson, Louis S., Robert J. 
LaLonde, and Daniel G. Sullivan, ``Earnings Losses of Displaced 
Workers.'' American Economic Review 83(4) (1993): 685-709.
---------------------------------------------------------------------------

    It is also true that, if a regulation comes into effect during a 
period of high unemployment, a change in labor demand due to regulation 
may affect net overall U.S. employment because the labor market is not 
in equilibrium. Either negative or positive effects are possible. 
Schmalansee and Stavins \553\ point out that net positive employment 
effects are possible in the near term when the economy is at less than 
full employment due to the potential hiring of idle labor resources by 
the regulated sector to meet new requirements (e.g., to install new 
equipment) and new economic activity in sectors related to the 
regulated sector. In the longer run, the net effect on employment is 
more difficult to predict and will depend on the way in which the 
related industries respond to the regulatory requirements. As 
Schmalansee and Stavins note, it is possible that the magnitude of the 
effect on employment could vary over time, region, and sector, and 
positive effects on employment in some regions or sectors could be 
offset by negative effects in other regions or sectors. For this 
reason, they urge caution in reporting partial employment effects since 
it can ``paint an inaccurate picture of net employment impacts if not 
placed in the broader economic context.''
---------------------------------------------------------------------------

    \553\ Ibid.
---------------------------------------------------------------------------

    This rulemaking is expected to have a relatively small effect on 
net employment in the United States through the regulated sector--the 
truck and engine manufacturer industry--and several related sectors, 
specifically, industries that supply the truck and engine manufacturing 
industry (e.g., truck parts), the trucking industry itself, other 
industries involved in transporting goods (e.g., rail and shipping), 
the petroleum refining sector, and the retail sector. According to the 
U.S. Bureau of Labor Statistics, about 1.25 million people were 
employed in the truck transportation industry and about 675,000 people 
were employed in the motor vehicle parts industry between 2010 and 
2011.\554\ Although heavy-duty vehicles (HD) account for approximately 
4 percent of the vehicles on the road, these vehicles consume more than 
20 percent of on-road gasoline and diesel fuel use. As discussed in 
Chapter 5 of the RIA, this rulemaking is predicted to reduce the amount 
of fuel these vehicles use, and thus affect the petroleum refinery 
industry. The petroleum refinery industry employed about 65,000 people 
in the U.S. in 2009, the most recent year that employment estimates are 
available for this sector.\555\ Finally, since the net reduction in 
cost associated with these rules is expected to lead to lower 
transportation and shipping costs, in a competitive market a 
substantial portion of those cost savings will be passed along to 
consumers, who then will have additional discretionary income (how much 
of the cost is passed along to consumers depends on market structure 
and the relative price elasticities).
---------------------------------------------------------------------------

    \554\ U.S. Bureau of Labor Statistics seasonally-adjusted 
Current Employment Statistics Survey for the Truck Transportation 
Industry (NAICS 484) and the Motor Vehicle Parts Manufacturing 
Industry (NAICS 3363).
    \555\ U.S. Census Bureau, 2009 Annual Survey of Manufactures, 
Published December 3, 2010.
---------------------------------------------------------------------------

    Several commenters suggested that the HD vehicle rules would lead 
to an increase in employment in affected sectors by offering the 
potential for new employment opportunities in the design and production 
of new vehicle technologies. Also, these commenters suggested that 
since the U.S. manufacturers and suppliers are leaders in certain 
advanced truck technologies, this program has the potential to help 
them consolidate their leadership and thrive in a global market. In 
this context, several commenters referred to an assessment by the Union 
of Concerned Scientists (UCS) and CalStart of the economic and 
employment benefits of the improved efficiency in HD vehicles.\556\ The 
study predicts an increase in tens of thousands of jobs between 2020 
and 2030, as result of higher fuel efficiency for HD vehicles.
---------------------------------------------------------------------------

    \556\ Union of Concerned Scientists and CalStart, Delivering 
Jobs: The Economic Costs and Benefits of Improving Fuel Economy of 
Heavy Duty Vehicles, July, 2010. http://www.ucsusa.org/deliveringjobs.
---------------------------------------------------------------------------

    While the commenters find unambiguous employment increases as a 
result of this program, we find employment impacts to involve some 
complexity, as the discussion that follows shows. In addition, these 
quantitative estimates were derived using a standard input-output 
model, though the estimates themselves have not yet been peer reviewed. 
Input-output (I/O) models do not account for opportunity costs of 
labor--that is, all employment needs due to the regulatory change will 
be met by unemployed workers. In addition, I/O models assume no changes 
in the average use of labor per dollar of output in the affected 
sectors. For these and other reasons, these may at best be considered 
an imprecise upper bound on actual employment impacts.\557\
---------------------------------------------------------------------------

    \557\ Berck, Peter, and Sandra Hoffman. ``Assessing the 
Employment Impacts of Environmental and Natural Resource Policy.'' 
Environmental and Resource Economics 22 (2002): 133-156.
---------------------------------------------------------------------------

    Other commenters suggested that the rulemaking could have a 
negative impact on jobs if the rule was not appropriate, cost 
effective, and technologically feasible. These comments focused on the 
commenter's concern that the desirability, and therefore sales, of 
certain vehicles could be diminished by a poorly designed rule, or that 
customers of RVs in particular would not value fuel savings 
technologies. The preceding discussion of the conceptual framework 
suggests some potential reasons why consumers may not value fuel 
savings technologies. If vehicle sales decrease as the comments suggest 
such an impact could lead to job losses. Such comments were submitted 
by the National RV Dealers Association (RVDA) and the National 
Automobile Dealers Association (NADA).
    Determining the direction of employment effects even in the 
regulated industry may be difficult due to the presence of competing 
effects that lead to an ambiguous adjustment in employment as a result 
of environmental regulation. Morgenstern, Pizer and Shih identify three 
separate ways that employment levels may change in the regulated 
industry in response to a new (or more stringent) regulation.\558\
---------------------------------------------------------------------------

    \558\ See Morgenstern et al (2002), Note 550, above.
---------------------------------------------------------------------------

     Demand effect: Higher production costs due to the 
regulation will lead to higher market prices; higher prices in turn 
reduce demand for the good, reducing the demand for labor to make

[[Page 57351]]

that good. In the authors' words, the ``extent of this effect depends 
on the cost increase passed on to consumers as well as the demand 
elasticity of industry output''.
     Cost effect: As costs go up, plants add more capital and 
labor (holding other factors constant), with potentially positive 
effects on employment; in the authors' words, as ``production costs 
rise, more inputs, including labor, are used to produce the same amount 
of output''.
     Factor-shift effect: Post-regulation production 
technologies may be more or less labor-intensive (i.e., more/less labor 
is required per dollar of output) (``factor-shift effect''). In the 
authors' words, ``environmental activities may be more labor intensive 
than conventional production,'' meaning that ``the amount of labor per 
dollar of output will rise,'' though it is also possible that ``cleaner 
operations could involve automation and less employment, for example''.

The ``demand effect'' is expected to have a negative effect on 
employment, the ``cost effect'' to have a positive effect on 
employment, and the ``factor-shift effect'' has an ambiguous effect on 
employment. Without more information with respect to the magnitudes of 
these competing effects, it is not possible to predict the total effect 
environmental regulation will have on employment levels in a regulated 
sector.
    Morgenstern et al. estimated the effects on employment of spending 
on pollution abatement for four highly polluting/regulated industries 
(pulp and paper, plastics, steel, and petroleum refining). They 
conclude that increased abatement expenditures generally have not 
caused a significant change in employment in those sectors. More 
specifically, their results show that, on average across the industries 
studied, each additional $1 million spent on pollution abatement 
results in a (statistically insignificant) net increase of 1.5 jobs. 
While the specific sectors Morgenstern et al. examined are different 
than the sectors considered here, the methodology that Morgenstern et 
al. developed is still useful in this context.
(2) Overview of Affected Sectors
    The above discussion focuses on employment changes in the regulated 
sector, but the regulated sector is not the only source of changes in 
employment. In these rules, the regulated sectors are truck and engine 
manufacturers; they are responsible for meeting the standards set in 
these rules. The effects of these rules are also likely to have impacts 
beyond the directly regulated sector. Some of the related sectors which 
these rules are also likely to impact include: motor vehicle parts 
producers, to the extent that the truck and engine industries purchase 
components rather than manufacture them in-house; shipping and 
transport, because many companies in this sector purchase trucks and 
their operating costs will be affected by both higher truck prices and 
fuel savings; oil refineries due to reduced demand for petroleum-based 
fuels; and the final retail market, which is where any net cost 
reductions due to fuel savings are ultimately expected to be 
experienced. We acknowledge that there may be impacts in other sectors 
that are not discussed here, but we have sought to include the sectors 
where we think the impacts are most direct. The following discussion 
describes the direction of impacts on employment in these industries. 
The effects of the HD National Program on net U.S. employment depend, 
not only on their relative magnitudes, but also on employment levels in 
the overall economy. As previously discussed, in a full-employment 
economy these sector-specific impacts will be mostly offset by 
employment changes elsewhere in the economy and would not be expected 
to result in a net change in jobs. However, in an economy with 
significant unemployment these changes may affect net employment in the 
U.S.
(a) Truck and Engine Manufacturers
    The regulated sector consists of truck and engine manufacturers. 
Employment associated with manufacturing trucks and engines may be 
affected by the demand, cost, and factor-shift effects.
Demand Effect
    The demand effect depends on the effects of this rulemaking on HD 
vehicle sales. If vehicle sales increase, then more people will be 
required to assemble trucks and their components. If vehicle sales 
decrease, employment associated with these activities will 
unambiguously decrease. The effects of this rulemaking on HD vehicle 
sales depend on the perceived desirability of the new vehicles. Unlike 
in Morgenstern et al.'s study, where the demand effect decreased 
employment, there are countervailing possibilities in the HD market due 
to the fuel savings resulting from this program. On one hand, this 
rulemaking will increase vehicle costs; by itself, this effect would 
reduce vehicle sales. In addition, while decreases in vehicle 
performance would also decrease sales, this program is not expected to 
have any negative effect on vehicle performance. On the other hand, 
this rulemaking will reduce the fuel costs of operating the vehicle; by 
itself, this effect would increase vehicle sales, especially if 
potential buyers have an expectation of higher fuel prices. The 
agencies have not made an estimate of the potential change in vehicle 
sales. However as discussed in Preamble Section VIII.E.5 the agencies 
have estimated an increase in vehicle miles traveled (i.e., VMT 
rebound) due to the reduced operating costs of trucks meeting these new 
standards. Since increased VMT is most likely to be met with more 
drivers and more trucks, our projection of VMT rebound is suggestive of 
an increase in vehicle sales and truck driver employment (recognizing 
that these increases may be partially offset by a decrease in 
manufacturing and sales for equipment of other modes of transportation 
such as rail cars or barges).
    As discussed above in Section VIII.A, the agencies find that the 
reduction in fuel costs associated with this rulemaking outweigh the 
increase in vehicle cost. This finding is puzzling: market forces 
should lead truck manufacturers and buyers to install all cost-
effective fuel-saving technology, but the agencies find that they have 
not. Section VIII.A discusses various hypotheses that have been 
suggested to explain this phenomenon. Some of the explanations suggest 
that vehicle manufacturers and buyers will benefit from the rulemaking, 
and vehicle sales will increase; others suggest that the opposite might 
occur. The agencies do not have strong evidence supporting one specific 
explanation over another. However, some in the heavy-duty industry 
indicate the potential for an increase in jobs. As stated by Tom 
Linebarger (President and Chief Operating Officer of Cummins) and Fred 
Krupp (President of the Environmental Defense Fund), ``Finally, strong 
environmental standards play a crucial role in getting innovations to 
market that will create economic opportunity for American companies and 
jobs for American workers. * * * It helps that Cummins and other 
forward-thinking businesses view this as an opportunity to innovate and 
increase international market share.'' \559\
---------------------------------------------------------------------------

    \559\ Tom Linebarger (President and Chief Operating Officer of 
Cummins) and Fred Krupp (President of the Environmental Defense 
Fund), ``Clear rules can create better engines, clean air,'' 
Indianapolis Star, October 28, 2010, p. 19; included as part of 
Cummins' comments on the rule, Docket Number EPA-HQ-OAR-2010-0162-
1765.1[1].
---------------------------------------------------------------------------

    One commenter raised the issue of whether there could be a loss of 
recreation vehicle (RV) industry jobs due to a reduction in the sales 
of motor homes and towable RVs. As mentioned

[[Page 57352]]

above, the effects of this rulemaking on HD vehicle sales depend on the 
desirability of the new vehicles.
Cost Effect
    The truck and engine manufacturing sector has great flexibility in 
how to respond to the requirement for reduced greenhouse gases and 
increasing fuel efficiency, with a broad suite of technologies being 
available to achieve the standards. These technologies are described in 
detail in Chapter 2 of the RIA. Among these technologies, a distinction 
can be made between technologies that can be ``added on'' to 
conventional trucks versus those that replace features of a 
conventional truck. ``Added on'' features, such as auxiliary power 
units, require additional labor to install the technologies on trucks, 
thus clearly increasing labor demand (the ``cost effect''). The pure 
cost effect always increases employment, though the net effect on the 
regulated industry depends on its effects in combination with the 
demand and factor-shift effects.
Factor-Shift Effect
    For ``replacement'' technologies, the predicted impact on labor 
demand from regulation depends on the change in the amount of labor 
used to build and install one type of technology compared to another. 
In some cases, the new technologies are predicted to be more complex 
than the existing technologies and may therefore require additional 
labor installation inputs. In other cases, the opposite may be true: 
labor intensity may be lower for some replacement technologies.
    Most of the technologies that are expected to be used to meet these 
standards are replacement technologies. For example, almost all of the 
engine improvements involve replacement technologies that are not 
expected to significantly change the labor requirements. Similarly, 
regulations of the chassis on vocational vehicles will only require the 
installation of a different type of tire, which is also not expected to 
have large labor intensity impacts. Therefore, the potential magnitude 
of the factor shift effect is expected to be relatively small, though 
slightly positive due to the additional labor needed to install more 
complex technologies.
Summary for the Truck and Engine Manufacturing Sector
    For the truck and engine manufacturing sector, the demand effect 
may result in either increased or decreased employment; the cost effect 
is expected to increase employment; and the factor-shift effect is 
expected to have a small, possibly slightly positive effect on 
employment in this sector. The net effect on employment in this sector 
depends on the sum of these factors.
(b) Motor Vehicle Parts Manufacturing Sector
    Some vehicle parts are made in-house and would be included directly 
in the regulated sector. Others are made by independent suppliers and 
are not directly regulated, but they will be affected by the rules as 
well. The parts manufacturing sector will be involved primarily in 
providing ``add-on'' parts, or components for replacement parts built 
internally. If demand for these parts increases due to the increased 
use of these parts, employment effects in this sector are expected to 
be positive. If the demand effect in the regulated sectors is 
significantly negative enough, it is possible that demand for other 
parts may decrease. As noted, the agencies do not predict a direction 
for the demand effect.
(c) Transport and Shipping Sectors
    Although not directly regulated by these rules, employment effects 
in the transport and shipping sector are likely to result from these 
regulations. If the overall cost of shipping a ton of freight decreases 
because of increased fuel efficiency (taking into account the increase 
in upfront purchasing costs), in a perfectly competitive industry these 
costs savings will be passed along to customers. With lower prices, 
demand for shipping would lead to an increase in demand for truck 
shipping services (consistent with the VMT rebound effect analysis) and 
therefore an increase in employment in the truck shipping sector. In 
addition, if the relative cost of shipping freight via trucks becomes 
cheaper than shipping by other modes (e.g., rail or barge), then 
employment in the truck transport industry is likely to increase. If 
the trucking industry is more labor intensive than other modes, we 
would expect this effect to lead to an overall increase in employment 
in the transport and shipping sectors.560 561 Such a shift 
would, however, be at the expense of employment in the sectors that are 
losing business to trucking. The first effect--a gain due to lower 
shipping costs--is likely to lead to a net increase in employment. The 
second effect, due to mode-shifting, may increase employment in 
trucking, but decreases in other shipping sectors.
---------------------------------------------------------------------------

    \560\ American Transportation Research Institute, ``An Analysis 
of the Operational Costs of Trucking: 2011 Update.'' See http://www.atri-online.org/research/results/Op_Costs_2011_Update_one_page_summary.pdf.
    \561\ Association of American Railroads, ``All Inclusive Index 
and Rail Adjustment Factor.'' June 3, 2011. See http://www.aar.org/
~/media/aar/RailCostIndexes/AAR-RCAF-2011-Q3.ashx.
---------------------------------------------------------------------------

(d) Fuel Suppliers
    In addition to the effects on the trucking industry and related 
truck parts sector, these rules will result in reductions in fuel use 
that lower GHG emissions. Fuel saving, principally reductions in liquid 
fuels such as diesel and gasoline, will affect employment in the fuel 
suppliers industry sectors, principally the Petroleum Refinery 
sector.\562\
---------------------------------------------------------------------------

    \562\ North American Industry Classification System (NAICS) Code 
32411.
---------------------------------------------------------------------------

    Expected fuel consumption reductions by fuel type, and by heavy-
duty vehicle type, can be found in Table VIII-7. These reductions 
reflect impacts from the new fuel efficiency and GHG standards and 
include increased consumption from the rebound effect. These fuel 
savings are monetized in Table VIII-8 by multiplying the reduced fuel 
consumption in each year by the corresponding estimated average fuel 
price in that year, using the Reference Case from the AEO 2011. In 
2014, the pre-tax fuel savings is $1.2 billion (2009$). While these 
figures represent a level of fuel savings for purchasers of fuel, it 
also represents a loss in value of output for the petroleum refinery 
industry. Since 50 percent of the fuel would have been refined in the 
U.S., the loss in output to the U.S. Petroleum Refinery sector is $600 
million (2009$), which will result in reduced sectoral employment.\563\ 
Because this sector is very capital-intensive, the employment effect is 
not expected to be large.
---------------------------------------------------------------------------

    \563\ EPA and NHTSA estimate that approximately 50 percent of 
the reduction in fuel consumption resulting from adopting improved 
fuel GHG standards and fuel efficiency standards is likely to be 
reflected in reduced U.S. imports of refined fuel, while the 
remaining 50 percent is expected to be reflected in reduced domestic 
fuel refining. Of this latter figure, 90 percent is anticipated to 
reduce U.S. imports of crude petroleum for use as a refinery 
feedstock, while the remaining 10 percent is expected to reduce U.S. 
domestic production of crude petroleum. Because we do not expect to 
see a significant reduction in crude oil production in the U.S., we 
do not expect this rule to have a significant impact on the Oil and 
Gas Extraction industry sector in the U.S. (NAICS 211000). For more 
information, refer to Section VIII-I on the energy security impacts 
from the program.
---------------------------------------------------------------------------

(e) Fuel Savings
    As a result of this rulemaking, it is anticipated that trucking 
firms will experience fuel savings. Fuel savings lower the costs of 
transportation goods and services. In a competitive market, the fuel 
savings that initially accrue to trucking firms are likely to be passed 
along as lower transportation costs that, in turn, could result in 
lower prices for

[[Page 57353]]

final goods and services. Alternatively, the savings could be kept 
internally in firms for investments or for returns to firm owners. In 
either case, the savings will accrue to some segment of consumers: 
either owners of trucking firms or the general public. In both cases, 
the effect will be increased spending by consumers in other sectors of 
the economy, creating jobs in a diverse set of sectors, including 
retail and service industries.
    As mentioned above, the value of fuel savings from this rulemaking 
is projected to be $1.2 billion (2009$) in 2014, according to Table 
VIII-8. If all those savings are spent, the fuel savings will stimulate 
increased employment in the economy through those expenditures. If the 
fuel savings accrue primarily to firm owners, they may either reinvest 
the money or take it as profit. Reinvesting the money in firm 
operations would increase employment directly. If they take the money 
as profit, to the extent that these owners are wealthier than the 
general public, they may spend less of the savings, and the resulting 
employment impacts would be smaller than if the savings went to the 
public. Thus, while fuel savings are expected to decrease employment in 
the refinery sector, they are expected to increase employment through 
increased consumer expenditures.
(3) Summary of Employment Impacts
    The net employment effects of this rulemaking are expected to be 
found throughout several key sectors: truck and engine manufacturers, 
the trucking industry, truck parts manufacturing, fuel production, and 
consumers. For the regulated sector, the demand effect may result in 
either increased or decreased employment, depending on the net effect 
on HD vehicle sales; the cost effect is expected to increase employment 
in the regulated sector; and the factor-shift effect is expected to 
have a small, possibly slightly positive effect on employment, though 
we cannot definitively say this is the case without quantification. The 
net effect depends on the combination of these effects. Increased 
expenditures by truck and engine parts manufacturers are expected to 
require increased labor to build parts, though this effect also depends 
on any changes in overall demand and on the labor intensity of 
production of new parts; increased complexity of technologies may imply 
increased labor inputs for some parts, though others might be less 
labor-intensive. It is possible, if access to capital markets is 
limited, that this rule might displace other HD sector investment, 
which would reduce employment associated with those activities. Lower 
prices for shipping are expected to lead to an increase in demand for 
truck shipping services and, therefore, an increase in employment in 
that sector, though this effect may be offset somewhat by changes in 
employment in other shipping sectors. Reduced fuel production implies 
less employment in the fuel provision sectors. Finally, any net cost 
savings would be expected to be passed along to some segment of 
consumers: either the general public or the owners of trucking firms, 
who are expected then to increase employment through their 
expenditures. Given the job creation as a result of the $1.2B (2009$) 
in fuel savings in 2014 and the possible employment increases in the 
manufacturing and parts sectors, we find it highly unlikely that there 
would be significant net job losses related to this policy. Given the 
current level of unemployment, net positive employment effects are 
possible, especially in the near term, due to the potential hiring of 
idle labor resources by the regulated sector to plan for and meet new 
requirements. In the future, when full employment is expected to 
return, any changes in employment levels in the regulated sector due to 
this program are mostly expected to be offset by changes in employment 
in other sectors.

IX. Analysis of the Alternatives

    The heavy-duty truck segment is very complex. The sector consists 
of a diverse group of impacted parties, including engine manufacturers, 
chassis manufacturers, truck manufacturers, trailer manufacturers, 
truck fleet owners and the public. The final standards that the 
agencies have adopted today maximize the environmental and fuel savings 
benefits of the program while taking into consideration the unique and 
varied nature of the regulated industries. In developing this final 
rulemaking, we considered a number of alternatives that could have 
resulted in potentially fewer or greater GHG and fuel consumption 
reductions than the program we are finalizing. This section summarizes 
the alternatives we considered and presents assessments of technology 
costs, CO2 reductions, and fuel savings associated with each 
alternative. The agencies reduced the number of alternatives analyzed 
in this final rulemaking compared to the proposal because we did not 
receive any comments supporting standard setting for a smaller subset 
than HD pickup trucks, combination tractors, and vocational vehicles 
(as well as engines installed in vocational vehicles and combination 
tractors). As discussed below, the agencies have also refined some of 
the alternatives analyzed in response to the comments received.

A. What are the alternatives that the agencies considered?

    In developing alternatives, NHTSA must consider EISA's requirement 
for the MD/HD fuel efficiency program noted above. 49 U.S.C. 
32902(k)(2) and (3) contain the following three requirements specific 
to the MD/HD vehicle fuel efficiency improvement program: (1) The 
program must be ``designed to achieve the maximum feasible 
improvement''; (2) the various required aspects of the program must be 
appropriate, cost-effective, and technologically feasible for MD/HD 
vehicles; and (3) the standards adopted under the program must provide 
not less than four model years of lead time and three model years of 
regulatory stability. In considering these various requirements, NHTSA 
will also account for relevant environmental and safety considerations.
    The alternatives below represent a broad range of approaches for a 
HD vehicle fuel efficiency and GHG emissions program. Details regarding 
the modeling of each alternative are included in RIA Chapter 6. The 
alternatives in order of increasing fuel efficiency and GHG emissions 
reductions are:
(1) Alternative 1: No Action
    A ``no action'' alternative assumes that the agencies would not 
issue rules regarding a MD/HD fuel efficiency improvement program. This 
alternative is presented in order for NHTSA to comply with the National 
Environmental Policy Act (NEPA) and to provide an analytical baseline 
against which to compare environmental impacts of the other regulatory 
alternatives.\564\ The agencies refer to this as the ``No Action 
Alternative'' or as a ``no increase'' or ``baseline'' alternative. As 
described in RIA Chapter 5, this no-

[[Page 57354]]

action alternative is considered the reference case.
---------------------------------------------------------------------------

    \564\ NEPA requires agencies to consider a ``no action'' 
alternative in their NEPA analyses and to compare the effects of not 
taking action with the effects of the reasonable action alternatives 
to demonstrate the different environmental effects of the action 
alternatives. See 40 CFR 1502.2(e), 1502.14(d).CEQ has explained 
that ``[T]he regulations require the analysis of the no action 
alternative even if the agency is under a court order or legislative 
command to act. This analysis provides a benchmark, enabling 
decision makers to compare the magnitude of environmental effects of 
the action alternatives. [See 40 CFR 1502.14(c).] * * * Inclusion of 
such an analysis in the EIS is necessary to inform Congress, the 
public, and the President as intended by NEPA. [See 40 CFR 
1500.1(a).]'' Forty Most Asked Questions Concerning CEQ's National 
Environmental Policy Act Regulations, 46 FR 18026 (1981) (emphasis 
added).
---------------------------------------------------------------------------

    The no action alternative first presented in this final action is 
based on the assumption that the new vehicle fleet continues to perform 
at the same level as new 2010 vehicles. In this way, it provides a 
comparison between today's new trucks and the increased cost and 
reduced fuel consumption of future compliant vehicles.
    The agencies recognize that there is substantial uncertainty in 
determining an appropriate baseline against which to compare the 
effects of the proposed action. The lack of prior regulation of HD fuel 
efficiency means that there is a lack of historic data regarding trends 
in this sector. Therefore, in this final action, the agencies have also 
included an analysis using a baseline derived from annual projections 
developed by the U.S. Energy Information Administration (EIA) for the 
Annual Energy Outlook (AEO). For this alternative baseline, the 
agencies analyzed the new truck fuel economy projections for the Light 
Commercial Trucks, along with the Medium- and Heavy-Duty Freight 
Vehicles developed in AEO 2011.\565\ The agencies converted the fuel 
economy improvements into CO2 emissions reductions relative 
to a 2010 model year (See RIA Chapter 6).
---------------------------------------------------------------------------

    \565\ U.S. Energy Information Administration. Annual Energy 
Outlook 2011 Early Release. Last viewed on March 29, 2011 at http://www.eia.doe.gov/forecasts/aeo/. See Supplemental Tables 7, 63, and 
68.
---------------------------------------------------------------------------

    The baseline derived from the AEO forecast provides a comparison 
between the impacts of the proposed standards and EIA's projection of 
future new truck performance absent regulation. This alternative 
baseline is informative in showing one possible projection of future 
vehicle performance based on other factors beyond the regulation the 
agencies are finalizing today. The AEO forecast makes a number of 
assumptions that should be noted. AEO 2011 assumes improved fuel 
efficiency for 8,500-10,000 lb. GVWR heavy-duty pickups due to the 
light-duty 2012-2016 MY regulations. We project a similar capability 
for fuel economy improvement as AEO does for this class of vehicles; 
however, the agencies recognize that absent regulation manufacturers 
may decline to add the necessary technologies to reach the level of our 
proposed standards. For medium- and heavy-duty vocational vehicles, AEO 
2011 projects a small reduction in fuel efficiency over time (an 
increase in fuel consumption), similar to that achieved under the MY 
2010 baseline. For Class 8 combination tractors, the AEO 2011 baseline 
projects an annual improvement of approximately 0.3 percent.
    We are not able to make an estimate of the cost of the AEO 2011 
alternative baseline because we are not able to accurately determine 
the technology mix used in the AEO 2011 analysis to achieve the 
projected improvements in fuel efficiency. We do know they differ 
significantly from our own analysis as the EIA projections do not 
include the full range of technologies considered by the agencies 
(e.g., EIA's analysis does not consider the use of idle reduction 
technologies and diesel auxiliary power units to reduce fuel 
consumption associated with vehicle hoteling). If one were to assume 
that the cost of the AEO2011 baseline was proportional to projected 
improvement relative to our preferred alternative, the total AEO2011 
baseline cost estimate would be approximately equal to the total cost 
of the preferred case, but would vary by category.
(2) Alternative 2: 12 Percent Less Stringent Than the Preferred 
Alternative
    Alternative 2 represents an alternative stringency level to the 
agencies' preferred approach. Alternative 2 represents a stringency 
level which is approximately 12 percent less stringent than the 
preferred approach. The agencies calculated the Alternative 2 
stringency level in order to meet two goals. First, we sought to create 
an alternative that regulated the same engine and vehicle categories as 
the preferred alternative, but at lower stringency (10-20 percent 
lower) than the preferred alternative. Second we wanted an alternative 
that reflected removal of the least cost effective technology that we 
believed manufacturers would add last in order to meet the preferred 
alternative. In other words, we wanted an alternative that as closely 
as possible reflected the last increment in stringency prior to 
reaching our preferred alternative. Please see Table 2-39 in RIA 
Chapter 2 for a list of all of the technologies, as well as their cost 
and relative effectiveness. The resulting Alternative 2 is based on the 
same technologies used in Alternative 3 except as follows for each of 
the three categories.
    The combination tractor standard would be based on the removal of 
the Advanced SmartWay aerodynamic package and weight reduction 
technologies, which decreases the average combination tractor GHG 
emissions and fuel consumption reduction by approximately 1 percent.
    The HD pickup truck and van standard would be based on removal of 
the 5 percent mass reduction technology, which decreases the average 
truck reduction of fuel consumption and GHG emissions by approximately 
1.6 percent.
    The vocational vehicle standard would be based on removal of low 
rolling resistance tires--in essence meaning that there would be no 
expected improvement in performance from vocational vehicles, only from 
engines used to power them. This alternative would also reduce the 
amount of technologies applied to diesel engines used in vocational 
vehicles such that the engines achieve a 3 percent reduction in 2014 
model year and a 5 percent reduction in 2017 model year, both compared 
to a 2010 model year baseline,
    The agencies have decided not to finalize Alternative 2, because as 
shown below, Alternative 3 is more stringent, is technically feasible, 
highly cost effective, and results in a greater net benefit to society.
(3) Alternative 3: Preferred Alternative and Final Standards
    Alternative 3 represents the agencies' preferred approach. This 
alternative consists of the finalized fuel efficiency and GHG standards 
for HD engines, HD pickup trucks and vans, Class 2b through Class 8 
vocational vehicles, and Class 7 and 8 combination tractors. Details 
regarding modeling of this alternative are included in RIA Chapter 5 as 
the control case.
    The agencies selected Alternative 3 over Alternatives 4 and 5 
described below because the agencies concluded that alternatives 4 and 
5 were not technically feasible to achieve given the leadtime provided 
in these final rules. Hence, we have concluded that Alternative 3 
represents the maximum feasible improvement. Section II of this 
preamble provides an explanation of the consideration that agencies 
gave to setting more stringent standards based on the application of 
additional technologies and our reasons for concluding that the 
identified technologies for each of the vehicle and engine standards 
that constitute Alternative 3 represented the maximum feasible 
improvement based on technological feasibility. In general, for 
advanced technologies, we reached this conclusion for one of two 
reasons. For some technologies such as Rankine Waste Heat Recovery 
engine technologies, the agencies have concluded that the technology is 
still in the research phase and will not be developed fully for new 
engine production in the time frame of this first regulatory action. In 
other cases, the agencies concluded that the

[[Page 57355]]

manufacturing capacity for technologies such as advanced battery 
systems for heavy-duty hybrid drivetrains could not be expanded quickly 
enough to allow for significant vehicle production volume in the time 
frame of this program. Section III also details the agencies' reasons 
for not basing standard stringencies on other technologies.
(4) Alternative 4: 20 Percent More Stringent Than the Preferred 
Alternative
    Alternative 4 represents a modeled alternative which is 20 percent 
more stringent than the preferred approach. The agencies derived the 
stringency level based on similar goals as for Alternative 2. 
Specifically, we wanted an alternative that would reflect an 
incremental improvement over the preferred alternative based on adding 
the next most cost effective technology in each of the categories. We 
believed these were the technologies most likely to be attempted by 
manufacturers if a more stringent standard were established. As 
discussed above and in the feasibility discussion in Section III, we 
are not finalizing Alternative 4 because we do not believe that the 
technologies used in this alternative can be developed and introduced 
in the time frame of this rulemaking. We note that the estimated costs 
for this alternative are denoted as `+c.' The +c is intended to make 
clear that the cost estimates we are showing do not include additional 
costs related to pulling ahead the development and expanding 
manufacturing base for the additional technologies (for example, 
building new factories in the next few years). The resulting 
Alternative 4 is based on the same technologies used in Alternative 3 
except as follows for each of the three categories.
    The combination tractor standard would be based on the addition of 
Rankine waste heat recovery systems and 100 percent application of 
advanced aerodynamic technologies, such as underbody airflow treatment, 
advanced gap reduction, rearview cameras to replace mirrors, and wheel 
system streamlining, to high roof sleeper cab combination tractors. The 
agencies do not believe that either advanced aerodynamic technologies 
or Rankine waste heat recovery systems should be used to set the 
standard for HD engines in 2017 MY because this technology is still in 
the research phase. The agencies assumed 59 percent of all combination 
tractors are sleeper cabs and of those, 80 percent are high roof 
sleeper cabs. The agencies assumed a 12 kWh waste heat recovery system 
would reduce CO2 emissions by 6 percent at a cost of $8,400 
per truck.\566\ The estimated reduction in CO2 emissions 
from the engine for this alternative is included in RIA Chapter 6. The 
impact of 100 percent application of the advanced aerodynamic 
technology package would lead to a total 20.7 percent reduction in Cd 
values for high roof sleeper cabs over a 2010 MY baseline tractor. The 
incremental cost of this technology over the preferred case is $1,027 
per vehicle.
---------------------------------------------------------------------------

    \566\ TIAX. 2009. Note 198, Page 4-20.
---------------------------------------------------------------------------

    The HD pickup truck and van standard would be based on the addition 
of the turbocharged, downsized technology to gasoline engines which 
would bring the total reduction for gasoline HD pickup trucks and vans 
to 15 percent and match the level of reduction for the diesel pickup 
trucks. The agencies do not consider this to be a technology from which 
the 2017MY gasoline HD pickup truck standards should be premised on 
because we are not yet convinced that turbocharged downsized gasoline 
engines can be applied to heavy-duty truck applications in a durable 
manner. We are aware that manufacturers are testing such engines and 
that in pickup trucks with a duty cycle representing a mix of passenger 
vehicle and work applications the engines can be durable. However, we 
are unable to conclude today that such engines will be durable and 
hence technically feasible when applied in heavy-duty truck 
applications with an expected higher average load factor. The estimated 
incremental cost increase to HD pickup trucks and vans to replace a 
stoichiometric gasoline direct injected V8 engine with coupled cam 
phasing used in Alternative 3 with a V6 stoichiometric gasoline direct 
injection DOHC with dual cam phasing, discrete valve lift, and twin 
turbochargers is estimated to be $1,743.\567\
---------------------------------------------------------------------------

    \567\ See RIA chapter 2, Table 2.35.
---------------------------------------------------------------------------

    The vocational vehicle standard would be based on the addition 
hybrid powertrains to 6 percent of the vehicles. The agencies assumed a 
32 percent per vehicle reduction in GHG emissions and fuel consumption 
due to the hybrid with a cost of $26,667 per vehicle based on the 
average effectiveness and costs developed in the NAS report for box 
trucks, bucket trucks, and refuse haulers.\568\
---------------------------------------------------------------------------

    \568\ Committee to Assess Fuel Economy Technologies for Medium- 
and Heavy-Duty Vehicles; National Research Council; Transportation 
Research Board (2010). ``Technologies and Approaches to Reducing the 
Fuel Consumption of Medium- and Heavy-Duty Vehicles,'' (``NAS 
Report''). Washington, DC The National Academies Press. Available 
electronically from the National Academies Press Web site at http://www.nap.edu/catalog.php?record_id=12845. Page 146.
---------------------------------------------------------------------------

(5) Alternative 5: Trailers Plus Accelerated Hybrid
    Alternative 5 builds on Alternative 4 through additional hybrid 
powertrain application rates in the HD sector and by adding a 
performance standard for fuel efficiency and GHG emissions to 
commercial trailers. This alternative includes all elements of 
Alternative 4 (some of which we already regard as infeasible in the 
model years covered by the final rules), plus the application of 
additional hybrid powertrains to the pickup trucks, vans, vocational 
vehicles, and tractors. In addition, the agencies applied aerodynamic 
technologies to commercial box trailers, along with tire technologies 
for all commercial trailers.
    The agencies set the hybrid penetration for each category such that 
it represents 50 percent of the HD pickup truck and van segment, 50 
percent of vocational vehicles, and 5 percent of tractors in 2017 model 
year. The agencies have concluded that it is not feasible to achieve 
hybrid technology penetration rates at or even near these levels in the 
time frame of this rulemaking. As with Alternative 4, we include a +c 
in our cost estimates for this alternative to reflect additional costs 
not estimated by the agencies. The agencies assumed that a hybrid 
powertrain would provide a 32 percent reduction in CO2 
emissions and fuel consumption of a vocational vehicle at a projected 
cost of $26,667 per vehicle, based on the average of the NAS report 
findings for box trucks, bucket trucks, and refuse vehicles.\569\ The 
agencies are projecting a cost of $9,000 per vehicle for the HD pickup 
trucks and vans with an effectiveness of 18 percent, again based on the 
NAS report.\570\ Lastly, the effectiveness of hybrid powertrains 
installed in tractors was assumed to be 10 percent at a cost of $25,000 
based on the NAS report.\571\
---------------------------------------------------------------------------

    \569\ NAS Report. Page 146.
    \570\ NAS Report. Page 146.
    \571\ NAS Report. Page 146.
---------------------------------------------------------------------------

    The combination tractor technology package for Alternative 5 
includes the preferred alternative technologies, waste heat recovery 
and Advanced SmartWay aerodynamic package used in Alternative 4, and 
application of hybrid powertrains discussed above, in addition to a 
regulation for commercial trailers pulled by combination tractors. The 
agencies assumed a box trailer program would mirror the SmartWay 
program and include tire and aerodynamic requirements. The agencies 
added low rolling resistance tires to all commercial trailers, which 
are assumed to have 15 percent lower rolling resistance than the 
baseline

[[Page 57356]]

trailer tire which is equivalent to the target value required by 
SmartWay. The aerodynamics of the box trailers were assumed to improve 
the coefficient of drag for the combination tractor-trailer by 10 
percent through the application of technologies such as trailer skirts 
and gap reducers.\572\ These technologies would result in further 
reductions in drag coefficient and rolling resistance coefficient from 
the MY 2010 baseline. As stated above for hybrids, the agencies do not 
believe that it is possible to achieve technology penetration rates at 
or even near these levels in the time frame of this rulemaking.
---------------------------------------------------------------------------

    \572\ The Cd improvement of 10 percent for trailer improvements 
was derived from the TIAX report, Table 4-26 on page 4-50.
---------------------------------------------------------------------------

    The combination tractor costs for this alternative are equal to the 
costs in Alternative 4, plus $25,000 for hybrid powertrains in ten 
percent of tractors, plus the costs of trailers. The costs for the 
trailer program of Alternative 5 were derived based on the assumption 
that trailer aerodynamic improvements would cost $2,150 per trailer. 
This cost assumes side fairings and gap reducers and is based on the 
ICF cost estimate.\573\ The agencies applied the aerodynamic 
improvement to only box trailers, which represent approximately 60 
percent of the trailer sales. The agencies used $528 per trailer (2014 
MY cost) for low rolling resistance based on the agencies' estimate of 
$66 per tire in the tractor program. Lastly, the agencies assumed the 
trailer volume is equal to three times the tractor volume based on the 
3:1 ratio of trailers to tractors in the market today.
---------------------------------------------------------------------------

    \573\ Assumed retail prices of $1,300 for side skirts and $850 
for gap reducers based on the ICF Cost Report, page 90.
---------------------------------------------------------------------------

B. How Do These Alternatives Compare in Overall GHG Emissions 
Reductions and Fuel Efficiency and Cost?

    The agencies analyzed all five alternatives through the MOVES model 
to evaluate the impact of each alternative, as shown in Table IX-1. The 
table contains the annual CO2 and fuel savings in 2030 and 
2050 for each alternative (relative to the reference scenario of 
Alternative 1), presenting both the total savings across all regulatory 
categories, and for each regulatory category.
    Table IX-2 presents the annual technology costs associated with 
each alternative (relative to the reference scenario of Alternative 1) 
in 2030 and 2050 for each regulatory category. In addition, the total 
annual downstream impacts of NOX, CO, PM, and VOC emissions 
in 2030 for each of the alternatives are included in Table IX-3.
    Lastly, the agencies project the monetized net benefits associated 
with each alternative in 2030 and 2050 as shown in Table IX-4 and Table 
IX-5.

              Table IX-1--Annual CO2 and Oil Reductions Relative to Alternative 1 in 2030 and 2050
----------------------------------------------------------------------------------------------------------------
                                                     Downstream CO2 Reductions       Oil reductions  (billion
                                                               (MMT)                         gallons)
                                                 ---------------------------------------------------------------
                                                       2030            2050            2030            2050
----------------------------------------------------------------------------------------------------------------
Alt. 1 Baseline.................................               0               0               0               0
Alt. 1a AEO 2011 Baseline--Total................              39              90             3.9             9.0
Tractors........................................              29              73             2.9             7.1
HD Pickup Trucks................................               9              16             0.9             1.7
Vocational Vehicles.............................               1               2             0.1             0.2
Alt. 2 Less Stringent--Total....................              54              78             5.4             7.7
Tractors........................................              42              59             4.2             5.8
HD Pickup Trucks................................               7              11             0.8             1.2
Vocational Vehicles.............................               5               7             0.4             0.7
Alt. 3 Preferred--Total.........................              61              88             6.0             8.7
Tractors........................................              45              63             4.4             6.2
HD Pickup Trucks................................               8              13             0.9             1.3
Vocational Vehicles.............................               7              11             0.7             1.1
Alt. 4 More Stringent--Total....................              74             107             7.4            10.7
Tractors........................................              53              74             5.2             7.3
HD Pickup Trucks................................              10              15             1.0             1.6
Vocational Vehicles.............................              11              18             1.1             1.8
Alt. 5 Max Technology--Total....................              99             146             9.8            14.5
Tractors........................................              61              85             6.0             8.3
HD Pickup Trucks................................              15              24             1.6             2.5
Vocational Vehicles.............................              23              37             2.2             3.6
----------------------------------------------------------------------------------------------------------------

  Table IX-2--Technology Cost Projections Relative to Alternative 1 for
                            Each Alternative
------------------------------------------------------------------------
                                               Technology costs \a\
                                                 (Millions, 2009$)
                                         -------------------------------
                                               2030            2050
------------------------------------------------------------------------
Alt. 1 Baseline.........................              $0              $0
Alt. 1a AEO 2011 Baseline--Total \b\....              --              --
Tractors................................              --              --
HD Pickup Trucks........................              --              --
Vocational Vehicles.....................              --              --
Alt. 2 Less Stringent--Total............          $1,676          $2,440
Tractors................................             743           1,227
HD Pickup Trucks........................             817           1,029
Vocational Vehicles.....................             117             185
Alt. 3 Preferred--Total.................           2,210           3,287

[[Page 57357]]

 
Tractors................................           1,076           1,777
HD Pickup Trucks........................             918           1,156
Vocational Vehicles.....................             216             354
Alt. 4 More Stringent--Total............         5,211+c         6,996+c
Tractors................................         1,953+c         3,225+c
HD Pickup Trucks........................         1,442+c         1,816+c
Vocational Vehicles.....................         1,816+c         1,954+c
                                                17,909+c        27,306+c
Alt. 5 Max Technology--Total............         2,747+c         4,292+c
Tractors................................         5,669+c         7,142+c
HD Pickup Trucks........................         9,493+c        15,873+c
Vocational Vehicles.....................         5,211+c        6,996+c
------------------------------------------------------------------------
Notes:
\a\ The +c is intended to make clear that the cost estimates we are
  showing do not include additional costs related to pulling ahead the
  development and expanding manufacturing base for these technologies.
\b\ The agencies did not conduct a cost analysis for the AEO2011
  baseline.

      Table IX-3--Downstream Impacts Relative to Alternative 1 of Key Non-GHGs for Each Alternative in 2030
                                                  [In percent]
----------------------------------------------------------------------------------------------------------------
                                                        NOX             CO             PM2.5            VOC
----------------------------------------------------------------------------------------------------------------
Alt. 1 Baseline.................................               0               0               0               0
Alt. 1a AEO 2011 Baseline.......................             8.8             1.0            -3.8             7.2
Alt. 2 Less Stringent...........................           -21.9            -2.0             8.4           -19.0
Alt. 3 Preferred................................           -22.0            -2.0             8.5           -19.1
Alt. 4 More Stringent...........................           -22.5            -2.0             8.7           -19.5
Alt. 5 Max Technology...........................           -22.9            -2.1             8.4           -20.0
----------------------------------------------------------------------------------------------------------------

  Table IX-4--Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                      2014 Through 2018 Model Year Vehicles
                                       [3% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0          $5,900          $8,100       $20,700+c       $37,200+c
Fuel Savings (pre-tax)..........               0          45,000          50,100          63,900          79,100
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0           1,100           1,200           1,600           1,900
3% (avg SCC)....................               0           5,100           5,700           7,200           9,000
2.5% (avg SCC)..................               0           8,400           9,400          12,000          15,000
3% (95th percentile)............               0          16,000          17,000          22,000          27,000
Energy Security Impacts (price                 0           2,400           2,700           3,400           4,200
 shock).........................
Accidents, Congestion, Noise \e\               0          -1,300          -1,500          -1,600          -1,600
Refueling Savings...............               0             300             400             500             600
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0          41,600          44,800        47,100+c        47,000+c
3% (avg SCC)....................               0          45,600          49,300        52,700+c        54,100+c
2.5% (avg SCC)..................               0          48,900          53,000        57,500+c        60,100+c
3% (95th percentile)............               0          56,500          60,600        67,500+c        72,100+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: 5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions
  expected under this rulemaking (See RIA Chapter 5). Although EPA has not monetized changes in non-CO2 GHGs,
  the value of any increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

[[Page 57358]]

  Table IX-5--Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                      2014 Through 2018 Model Year Vehicles
                                       [7% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0          $5,900          $8,100       $20,700+c       $37,200+c
Fuel Savings (pre-tax)..........               0          30,900          34,400          43,800          53,900
----------------------------------------------------------------------------------------------------------------
                             Reduced CO2 Emissions at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0           1,100           1,200           1,600           1,900
3% (avg SCC)....................               0           5,100           5,700           7,200           9,000
2.5% (avg SCC)..................               0           8,400           9,400          12,000          15,000
3% (95th percentile)............               0          16,000          17,000          22,000          27,000
Energy Security Impacts (price                 0           1,600           1,800           2,300           2,900
 shock).........................
Accidents, Congestion, Noise \e\               0            -900          -1,000          -1,100          -1,100
Refueling Savings...............               0             200             200             300             400
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                            Monetized Net Benefits at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0          27,000          28,500        26,200+c        20,800+c
3% (avg SCC)....................               0          31,000          33,000        31,800+c        27,900+c
2.5% (avg SCC)..................               0          34,300          36,700        36,600+c        33,900+c
3% (95th percentile)............               0          41,900          44,300        46,600+c        45,900+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ The monetized GHG benefits presented in this analysis exclude the value of changes in non-CO2 GHG emissions
  expected under this rulemaking (See RIA chapter 5). Although EPA has not monetized changes in non-CO2 GHGs,
  the value of any increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

    The agencies also project the monetized net benefits associated 
with each alternative by vehicle class for the 2014 through 2018 MY 
vehicles over their lifetimes as shown in Table IX-6 through Table IX-8 
at a three percent discount rate for HD pickup trucks & vans, 
vocational vehicles and combination tractors, respectively, and in 
Table IX-9 through Table IX-11 at a seven percent discount rate for HD 
pickup trucks and vans, vocational vehicles and combination tractors, 
respectively.

  Table IX-6--Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                              2014 Through 2018 Model Year HD Pickup Trucks & Vans
                                       [3% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0          $1,780          $1,970        $3,220+c        $9,890+c
Fuel Savings (pre-tax)..........               0           3,480           4,060           4,910           7,700
Energy Security Impacts (price                 0             190             220             270             420
 shock).........................
Accidents, Congestion, Noise \e\               0            -330            -350            -370            -350
Refueling Savings...............               0              40              50              60              90
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             100             100             100             200
3% (avg SCC)....................               0             500             500             600             900
2.5% (avg SCC)..................               0             800             900           1,100           1,500
3% (95th percentile)............               0           1,400           1,600           1,900           2,800
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0           1,700           2,110         1,750+c        -1,830+c
3% (avg SCC)....................               0           2,100           2,510         2,250+c        -1,130+c
2.5% (avg SCC)..................               0           2,400           2,910         2,750+c          -530+c

[[Page 57359]]

 
3% (95th percentile)............               0           3,000           3,610         3,550+c           770+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

  Table IX-7 Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                2014 Through 2018 Model Year Vocational Vehicles
                                       [3% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0            $670          $1,140        $9,140+c       $15,840+c
Fuel Savings (pre-tax)..........               0           3,420           5,420           8,930          14,270
Energy Security Impacts (price                 0             180             290             480             760
 shock).........................
Accidents, Congestion, Noise \e\               0            -540            -650            -670            -500
Refueling Savings...............               0              40              60             110             170
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             100             100             200             300
3% (avg SCC)....................               0             400             600           1,000           1,500
2.5% (avg SCC)..................               0             700           1,100           1,700           2,600
3% (95th percentile)............               0           1,300           1,900           3,100           4,700
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0           2,530           4,080           -90+c          -840+c
3% (avg SCC)....................               0           2,830           4,580           710+c           360+c
2.5% (avg SCC)..................               0           3,130           5,080         1,410+c         1,460+c
3% (95th percentile)............               0           3,730           5,880         2,810+c         3,560+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

  Table IX-8--Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                2014 through 2018 Model Year Combination Tractors
                                       [3% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0          $3,300          $4,950        $8,430+c       $11,540+c
Fuel Savings (pre-tax)..........               0          38,140          40,650          50,030          57,190
Energy Security Impacts (price                 0           2,030           2,160           2,660           3,040
 shock).........................
Accidents, Congestion, Noise \e\               0            -450            -480            -590            -770
Refueling Savings...............               0             230             250             300             350
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------

[[Page 57360]]

 
                               Reduced CO2 Emissions at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             900           1,000           1,200           1,400
3% (avg SCC)....................               0           4,200           4,500           5,600           6,500
2.5% (avg SCC)..................               0           7,000           7,500           9,300          11,000
3% (95th percentile)............               0          13,000          14,000          17,000          20,000
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0          37,550          38,630        45,170+c        49,670+c
3% (avg SCC)....................               0          40,850          42,130        49,570+c        54,770+c
2.5% (avg SCC)..................               0          43,650          45,130        53,270+c        59,270+c
3% (95th percentile)............               0          49,650          51,630        60,970+c        68,270+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

  Table IX-9: Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                              2014 Through 2018 Model Year HD Pickup Trucks & Vans
                                       [7% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0          $1,780          $1,970        $3,220+c        $9,890+c
Fuel Savings (pre-tax)..........               0           2,180           2,550           3,090           4,830
Energy Security Impacts (price                 0             120             140             170             260
 shock).........................
Accidents, Congestion, Noise \e\               0            -220            -230            -250            -230
Refueling Savings...............               0              30              30              40              60
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                               Reduced CO2 Emissions at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             100             100             100             200
3% (avg SCC)....................               0             500             500             600             900
2.5% (avg SCC)..................               0             800             900           1,100           1,500
3% (95th percentile)............               0           1,400           1,600           1,900           2,800
----------------------------------------------------------------------------------------------------------------
                              Monetized Net Benefits at Each Assumed SCC Value a b
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             430             620           -70+c        -4,770+c
3% (avg SCC)....................               0             830           1,020           430+c        -4,070+c
2.5% (avg SCC)..................               0           1,130           1,420           930+c        -3,470+c
3% (95th percentile)............               0           1,730           2,120         1,730+c        -2,170+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

[[Page 57361]]

 Table 1X-10--Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                2014 Through 2018 Model Year Vocational Vehicles
                                       [7% Discount rate, millions, 2009$]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........              $0            $670          $1,140        $9,140+c       $15,840+c
Fuel Savings (pre-tax)..........               0           2,280           3,630           5,970           9,410
Energy Security Impacts (price                 0             120             190             320             500
 shock).........................
Accidents, Congestion, Noise \e\               0            -380            -450            -460            -350
Refueling Savings...............               0              30              40              70             110
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                             Reduced CO2 Emissions at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             100             100             200             300
3% (avg SCC)....................               0             400             600           1,000           1,500
2.5% (avg SCC)..................               0             700           1,100           1,700           2,600
3% (95th percentile)............               0           1,300           1,900           3,100           4,700
----------------------------------------------------------------------------------------------------------------
                            Monetized Net Benefits at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0           1,480           2,370        -3,040+c        -5,870+c
3% (avg SCC)....................               0           1,780           2,870        -2,240+c        -4,670+c
2.5% (avg SCC)..................               0           2,080           3,370        -1,540+c        -3,570+c
3% (95th percentile)............               0           2,680           4,170          -140+c        -1,470+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

  Table 1X-11 Monetized Net Benefits Associated With Each Alternative Relative to Alternative 1 for Lifetime of
                                2014 Through 2018 Model Year Combination Tractors
                                       [7% Discount rate, millions, 2009]
----------------------------------------------------------------------------------------------------------------
                                      Alt. 1        Alt. 2 less       Alt. 3        Alt. 4 more     Alt. 5 max
                                     baseline        stringent       preferred       stringent      technology
----------------------------------------------------------------------------------------------------------------
Truck Program Costs \d\.........               0           3,300           4,950         8,430+c        11,540+c
Fuel Savings (pre-tax)..........               0          26,420          28,170          34,710          39,680
Energy Security Impacts (price                 0           1,410           1,500           1,850           2,110
 shock).........................
Accidents, Congestion, Noise \e\               0            -320            -340            -420            -550
Refueling Savings...............               0             160             170             210             240
Non-CO2 GHG Impacts and Non-GHG              N/A             N/A             N/A             N/A             N/A
 Impacts \c\....................
----------------------------------------------------------------------------------------------------------------
                             Reduced CO2 Emissions at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0             900           1,000           1,200           1,400
3% (avg SCC)....................               0           4,200           4,500           5,600           6,500
2.5% (avg SCC)..................               0           7,000           7,500           9,300          11,000
3% (95th percentile)............               0          13,000          14,000          17,000          20,000
----------------------------------------------------------------------------------------------------------------
                            Monetized Net Benefits at Each Assumed SCC Value \a\ \b\
----------------------------------------------------------------------------------------------------------------
5% (avg SCC)....................               0          25,270          25,550        29,120+c        31,340+c
3% (avg SCC)....................               0          28,570          29,050        33,520+c        36,440+c
2.5% (avg SCC)..................               0          31,370          32,050        37,220+c        40,940+c
3% (95th percentile)............               0          37,370          38,550        44,920+c        49,940+c
----------------------------------------------------------------------------------------------------------------
Notes:
\a\ Net present value of reduced CO2 emissions is calculated differently than other benefits. The same discount
  rate used to discount the value of damages from future emissions (SCC at 5, 3, and 2.5 percent) is used to
  calculate net present value of SCC for internal consistency. Refer to the SCC TSD for more detail.
\b\ Section VIII.G notes that SCC increases over time. Corresponding to the years in this table, the SCC
  estimates range as follows: for Average SCC at 5%: $5-$16; for Average SCC at 3%: $22-$46; for Average SCC at
  2.5%: $36-$66; and for 95th percentile SCC at 3%: $66-$139. Section VIII.G also presents these SCC estimates.
\c\ Due to analytical and resource limitations, MY non-GHG emissions (direct PM, VOCs, NO2 and SO2) were not
  estimated for this analysis. Although EPA has not monetized changes in non-CO2 GHGs, the value of any
  increases or reductions should not be interpreted as zero.
\d\ ``+c'' indicates additional costs not estimated in this rulemaking.

[[Page 57362]]

 
\e\ Negative sign represents an increase in Accidents, Congestion, and Noise.

C. What is the agencies' decision regarding trailer standards?

    A central theme throughout our HD Program is the recognition of the 
diversity and complexity of the heavy-duty vehicle segment. Trailers 
are an important part of this segment and are no less diverse in the 
range of functions and applications they serve. They are the primary 
vehicle for moving freight in the United States. The type of freight 
varies from retail products to be sold in stores, to bulk goods such as 
stones, to industrial liquids such as chemicals, to equipment such as 
bulldozers. Semi-trailers come in a large variety of styles--box, 
refrigerated box, flatbed, tankers, bulk, dump, grain, and many others. 
The most common type of trailer is the box trailer, but even box 
trailers come in many different lengths ranging from 28 feet to 53 feet 
or greater, and in different widths, heights, depths, materials (wood, 
composites, and/or aluminum), construction (curtain side or hard side), 
axle configuration (sliding tandem or fixed tandem), and multiple other 
distinct features. NHTSA and EPA believe trailers impact the fuel 
consumption and CO2 emissions from combination tractors and 
the agencies see opportunities for reductions. Unlike our experience 
with trucks and engines, the agencies have very limited experience 
related to regulating trailers for fuel efficiency or emissions. 
Likewise, the trailer manufacturing industry has only the most limited 
experience complying with regulations related to emissions and none 
with regard to EPA or NHTSA certification and compliance procedures.
    The agencies broadly solicited comments on controlling fuel 
efficiency and GHG emissions through eventual trailer regulations as we 
described in the notice of proposed rulemaking which could set the 
foundation of a future rulemaking for trailers. 75 FR at 74345-351 
(although this was a solicitation for comment regarding future action 
outside the present rulemaking).
    The general theme of the comments received was that technologies 
exist today that can improve trailer efficiency. We received several 
comments from stakeholders which encouraged the agencies to set fuel 
efficiency and GHG emissions standards for trailers in this rulemaking. 
The agencies also received comments supporting a delay in trailer 
regulations. Specifically, IPI commented that the agencies should 
regulate trailers at least to some degree, arguing that the agencies' 
reasoning for not doing so was insufficient and requesting a plan and 
schedule in the final rule for the future regulation of trailers. One 
commenter recognized that there are well over 100 trailer manufacturers 
in the U.S., with almost all being small businesses. They stressed the 
need for the agencies to reach out to the trailer industry and 
associations prior to developing a regulatory program for this 
industry. In addition, they stated that time is needed to develop 
sufficient research into the area. None of the commenters that 
supported trailer regulation in this action addressed the complexities 
of the trailer industry, nor a method to measure trailer aerodynamic 
improvements.
    In the NPRM, the agencies discussed relatively conceptual 
approaches to how a future trailer regulation could be developed; 
however, we did not provide a proposed test procedure or proposed 
standard. The agencies proposed to delay the regulation of trailers, as 
the inclusion would not be feasible at this time due to the lack of a 
test procedure and the myriad of technical and policy issues not teed 
up in the NPRM or addressed in comments. Additionally, since a number 
of trailer manufacturing entities are small businesses, EPA and NHTSA 
need to allow sufficient time to convene a SBREFA panel to conduct the 
proper outreach to the potentially impacted stakeholders. As noted 
earlier, the agencies do not believe it warranted to delay the 
combination tractor and vocational vehicle standards for the years it 
will take to resolve these issues. NHTSA and EPA agree that the 
regulation of trailers, when appropriate, is likely to provide fuel 
efficiency benefits. We continue to believe that both agencies must 
perform a more comprehensive assessment of the trailer industry, and 
therefore that their inclusion at this time is not feasible. Until that 
time, the SmartWay Transport Partnership Program will continue to 
encourage the development and use of technologies to reduce fuel 
consumption and CO2 emissions from trailers.

X. Public Participation

    The agencies proposed their respective rules on November 30, 2010 
(75 FR 74152). Two public hearings were held to provide interested 
parties the opportunity to present data, views, or arguments concerning 
the proposal; the first hearing was held in Chicago, IL on November 15, 
2010, and the second in Cambridge, MA on November 18, 2010. The public 
was invited to submit written comments on the proposal during the 
formal comment period, which ended on January 31, 2011. The agencies 
received over 41,000 comments--over 3,000 of them unique--from 
industry, environmental organizations, states, and individuals.
    The vast majority of commenters supported the central tenets of the 
proposed HD National Program. That is, there was broad support for a 
national program which would reduce fuel consumption and GHG emissions 
from the three heavy-duty regulatory categories--heavy-duty pickup 
trucks and vans, vocational vehicles, and combination tractors. The 
agencies received specific comments on many aspects of the proposal.
    Throughout this notice, the agencies discuss many of the key issues 
arising from the public comments and the agencies' responses. In 
addition, the agencies have addressed all of the public comments in the 
Response to Comments document associated with this final action and 
located in the docket (Docket ID EPA-HQ-OAR-2010-0162, or NHTSA-2010-
0079).

XI. NHTSA's Record of Decision

    On May 21, 2010, President Obama issued a memorandum entitled 
``Improving Energy Security, American Competitiveness and Job Creation, 
and Environmental Protection through a Transformation of our Nation's 
Fleet of Cars and Trucks'' to the Secretary of Transportation, the 
Administrator of NHTSA, the Administrator of EPA, and the Secretary of 
Energy.\574\ The memorandum requested that the Administrators of EPA 
and NHTSA begin work on a Joint Rulemaking under EISA and the Clean Air 
Act and establish fuel efficiency and GHG emission standards for 
commercial medium- and heavy-duty vehicles beginning with MY 2014. The 
President requested that NHTSA implement fuel efficiency standards and 
EPA implement GHG emission standards that take into account the market 
structure of the trucking industry and the unique demands of heavy-duty 
vehicle applications; seek harmonization with applicable State 
standards; consider the findings and recommendations published in the 
National Academy of

[[Page 57363]]

Sciences (NAS) report on medium- and heavy-duty truck regulation; 
strengthen the industry and enhance job creation in the United States; 
and seek input from all stakeholders, while recognizing the continued 
leadership role of California and other States.
---------------------------------------------------------------------------

    \574\ The White House, Office of the Press Secretary, 
Presidential Memorandum Regarding Fuel Efficiency Standards (May 21, 
2010); The White House, Office of the Press Secretary, President 
Obama Directs Administration to Create First-Ever National 
Efficiency and Emissions Standards for Medium- and Heavy-Duty Trucks 
(May 21, 2010).
---------------------------------------------------------------------------

    In accordance with this policy, this Final Rule promulgates fuel 
efficiency standards for HD vehicles built in MYs 2014-2018. This Final 
Rule constitutes the Record of Decision (ROD) for NHTSA's HD vehicle 
Fuel Efficiency Improvement Program, pursuant to the National 
Environmental Policy Act (NEPA) and the Council on Environmental 
Quality's (CEQ) implementing regulations.\575\ See 40 CFR1505.2.
---------------------------------------------------------------------------

    \575\ NEPA is codified at 42 U.S.C. 4321-47. CEQ NEPA 
implementing regulations are codified at 40 Code of Federal 
Regulations (CFR) Parts 1500-08.
---------------------------------------------------------------------------

    As required by CEQ regulations, this Final Rule and ROD sets forth 
the following: (1) the agency's decision; (2) alternatives considered 
by NHTSA in reaching its decision, including the environmentally 
preferable alternative; (3) the factors balanced by NHTSA in making its 
decision, including considerations of national policy; (4) how these 
factors and considerations entered into its decision; and (5) the 
agency's preferences among alternatives based on relevant factors, 
including economic and technical considerations and agency statutory 
missions. This Final Rule also briefly addresses mitigation.

A. The Agency's Decision

    In the Draft Environmental Impact Statement (DEIS) and the Final 
Environmental Impact Statement (FEIS), the agency identified a 
Preferred Alternative which would set overall fuel consumption 
standards for HD vehicles and engines. The Preferred Alternative, 
identified as Alternative 3 in the FEIS, would include standards for 
engines used in Classes 2b-8 vocational vehicles (except engines in HD 
pickups and vans, which are regulated as complete vehicles), fuel 
consumption standards for HD pickups and vans by work factor, overall 
vehicle fuel consumption standards for Classes 2b-8 vocational vehicles 
(in gal/1,000 ton-miles), and overall fuel consumption standards for 
Classes 7 and 8 tractors.
    The Preferred Alternative identified in the NPRM, DEIS, and FEIS 
assumed that the vocational vehicle standards would lead to a 10 
percent reduction in the tire rolling resistance levels of the tires 
installed in vocational vehicles. After carefully reviewing and 
analyzing all of the information in the public record including 
technical support documents, the FEIS, and public and agency comments 
submitted on the DEIS, the FEIS, and the NPRM, NHTSA has decided to 
finalize a standard that includes slightly more stringent requirements 
for vocational vehicles than those included in the Preferred 
Alternative analyzed in the FEIS. Subsequent to issuing the proposed 
rule, NHTSA and EPA conducted a tire testing program to evaluate the 
tire rolling resistance of 156 different tires across a wide range of 
truck applications. The results of the study indicate that the baseline 
tire rolling resistance of this segment of vehicles was better than the 
level assumed during the proposal. In the final action, therefore, the 
agencies made the vocational truck standards slightly more stringent 
than those included as part of the Preferred Alternative for the FEIS, 
reflecting the better overall performance of tires in this segment. In 
addition, the agencies have reduced the projected improvement in 
average tire performance from 10 percent to 5 percent, reflecting the 
better than expected baseline performance. NHTSA's analysis indicates 
that the Agency's Decision will result in slightly less fuel savings 
and CO2 emissions reductions than those noted in the 
EIS.\576\ For environmental impacts associated with the final rule, see 
Sections VI.C and VII of this Final Rule.\577\
---------------------------------------------------------------------------

    \576\ The agencies' analysis indicates that the change results 
in a decrease in total 2014-2050 fuel savings of about 1.05% percent 
compared to the Preferred Alternative modeled in the EIS and a 
corresponding increase in CO2 emissions.
    \577\ The environmental impacts of this decision fall within the 
spectrum of impacts analyzed in the DEIS and the FEIS. There are no 
``substantial changes to the proposed action'' and there are no 
``significant new circumstances or information relevant to 
environmental concerns and bearing on the proposed action or its 
impacts.'' Therefore, consistent with 40 CFR 1502.9(c), no 
supplement to the EIS is required.
---------------------------------------------------------------------------

B. Alternatives Considered by NHTSA in Reaching Its Decision, Including 
the Environmentally Preferable Alternative

    When preparing an EIS, NEPA requires an agency to compare the 
potential environmental impacts of its proposed action and a reasonable 
range of alternatives. In the FEIS, NHTSA identified alternatives that 
represent the spectrum of potential actions the agency could take. The 
environmental impacts of these alternatives, in turn, represent the 
spectrum of potential environmental impacts that could result from 
NHTSA's chosen action in setting fuel efficiency standards for HD 
vehicles.
    The FEIS analyzed the impacts of four ``action'' alternatives, each 
of which would separately regulate segments of the HD vehicle 
fleet.\578\ Three of the action alternatives (Alternatives 2, 3 and 4) 
would regulate the same vehicle categories, but at increasing levels of 
stringency, with Alternative 2 being the least stringent alternative 
and Alternative 4 being the most stringent. Alternatives 2 and 4 were 
constructed by starting with the Preferred Alternative (Alternative 3) 
and either removing the least cost effective technology in each of the 
vehicle categories or adding the next most cost effective technology in 
each of the vehicle categories.\579\
---------------------------------------------------------------------------

    \578\ In the DEIS, NHTSA analyzed several alternatives that 
applied only to specific components and/or segments of the HD 
vehicle fleet. Many commenters urged the agency to consider 
alternatives that applied to the entire HD vehicle fleet, reasoning 
that such an approach would be more consistent with EISA 
requirements. After careful consideration, NHTSA decided that those 
alternatives that would set standards for the whole fleet--that is, 
the engine as well as the entire vehicle for pickup trucks and vans, 
vocational vehicles, and tractors--best met the purpose and need for 
this action. It also allows for the achievement of the ``maximum 
feasible improvement'' in HD fuel efficiency. Therefore, the FEIS 
examined impacts associated with four of the action alternatives 
analyzed in the DEIS.
    \579\ See Section 2.3.2 of the FEIS.
---------------------------------------------------------------------------

    Alternative 5 built on the Preferred Alternative by adding a 
performance standard for the commercial trailers pulled by tractors and 
by specifying more stringent standards based on accelerated adoption of 
hybrid powertrains for HD vehicles. The DEIS and FEIS also analyzed the 
impacts that would be expected if NHTSA adopted no HD vehicle standards 
(the No Action Alternative). For a discussion of the environmental 
impacts associated with each of the alternatives, see Chapters 3 and 4 
of the FEIS.
    Along with the FEIS, the agency conducted a national-scale 
photochemical air quality modeling and health risk assessment for a 
subset of the DEIS alternatives to support and confirm the health 
effects and health-related economic estimates of the EIS. The 
photochemical air quality study is included as Appendix F to the FEIS. 
The study used air quality modeling and health benefits analysis tools 
to quantify the air quality and health-related benefits associated with 
the alternative HD standards.
    NHTSA's environmental analysis indicates that Alternative 5 
(Trailers and Accelerated Hybrid) is the overall Environmentally 
Preferable Alternative because it would result in the largest 
reductions in fuel use and GHG emissions among the alternatives

[[Page 57364]]

considered. Under each action alternative the agency considered, the 
reduction in fuel consumption resulting from higher fuel efficiency 
causes emissions that occur during fuel refining and distribution to 
decline. For most pollutants, this decline is more than sufficient to 
offset the increase in tailpipe emissions that results from increased 
driving due to the fuel efficiency rebound effect, leading to a net 
reduction in total emissions from fuel production, distribution, and 
use. Because it leads to the largest reductions in fuel refining, 
distribution, and consumption among the alternatives considered, 
Alternative 5 would also lead to the lowest total emissions of 
CO2 and other GHGs, as well as most criteria air pollutants 
and mobile source air toxics (MSATs).\580\
---------------------------------------------------------------------------

    \580\ Emissions of fine particulate matter (PM2.5) 
and diesel particulate matter (DPM) for Alternative 5 are forecast 
to be lower than under other action alternatives under all analysis 
years, but slightly higher than under the No Action Alternative in 
analysis years 2030 and 2050. See FEIS Tables 3.5.2-1 and 3.5.2-5. 
This anomaly results from the agencies' assumptions regarding the 
percent of all long-haul tractors that use an APU rather than the 
truck's engine as a power source during extended idling (discussed 
further in FEIS Section 3.2.4.1).
---------------------------------------------------------------------------

    NHTSA's environmental analysis indicates that emissions of carbon 
monoxide (CO), acrolein, acetaldehyde, and formaldehyde are slightly 
(less than one percent) higher under Alternative 5 than under some 
other action alternatives and analysis years. This occurs when 
increased tailpipe emissions are forecast to exceed the reductions in 
emissions due to reduced fuel refining and distribution. Thus, while 
Alternative 5 is the environmentally preferable alternative on the 
basis of CO2 and other GHGs, and on the basis of most 
criteria air pollutants and MSATs, other alternatives are 
environmentally preferable from the standpoint of some criteria air 
pollutants and MSATs in some years. Overall, NHTSA considers 
Alternative 5 to be the Environmentally Preferable Alternative.
    For additional discussion regarding the alternatives considered by 
the agency in reaching its decision, including the Environmentally 
Preferable Alternative, see Section IX of this Final Rule. For a 
discussion of the environmental impacts associated with each 
alternative, see Chapters 3 and 4 of the FEIS.

C. Factors Balanced by NHTSA in Making Its Decision

    For discussion of the factors balanced by NHTSA in making its 
decision, see Sections III, VIII and IX of this Final Rule.

D. How the Factors and Considerations Balanced by NHTSA Entered Into 
Its Decision

    For discussion of how the factors and considerations balanced by 
the agency entered into NHTSA's Decision, see Sections III, VIII and IX 
of this Final Rule.

E. The Agency's Preferences among Alternatives Based on Relevant 
Factors, Including Economic and Technical Considerations and Agency 
Statutory Missions

    For discussion of the agency's preferences among alternatives based 
on relevant factors, including economic and technical considerations, 
see Section VIII and IX of this Final Rule.

F. Mitigation

    The CEQ regulations specify that a ROD must ``state whether all 
practicable means to avoid or minimize environmental harm from the 
alternative selected have been adopted, and if not, why they were 
not.'' 49 CFR 1505.2(c). The majority of the environmental effects of 
NHTSA's action are positive, i.e., beneficial environmental impacts, 
and would not raise issues of mitigation. Emissions of criteria and 
toxic air pollutants are generally projected to decrease under the 
final standards under all analysis years as compared to their levels 
under the No Action Alternative. Analysis of the environmental trends 
reported in the FEIS indicates that the only exceptions to this decline 
are emissions of PM2.5, DPM, and 1,3-butadiene in some 
analysis years. See Chapter 5 of the FEIS. The agency forecasts these 
emissions increases because, under all the alternatives analyzed in the 
EIS, increase in vehicle use due to improved fuel efficiency is 
projected to result in growth in total miles traveled by HD vehicles. 
The growth in travel outpaces emissions reductions for some pollutants, 
resulting in projected increases for these pollutants. In addition, 
NHTSA's NEPA analysis predicted increases in emissions of air toxic and 
criteria pollutants to occur under certain alternatives based on 
assumptions about the use of Auxiliary Power Units (APUs). For example, 
NHTSA's NEPA analysis assumes that some manufacturers will install 
anti-idling technologies (including APUs) on some vehicle classes to 
meet the requirements of the rule and that drivers' subsequent use of 
those APUs will result in an increase in emissions of some criteria and 
toxic air pollutants.
    NHTSA's authority to promulgate new fuel efficiency standards for 
HD vehicles is limited and does not allow regulation of vehicle 
emissions or of factors affecting vehicle emissions, including driving 
habits and APU usage. Consequently, under the HD Fuel Efficiency 
Improvement Program, NHTSA must set standards but is unable to take 
steps to mitigate the impacts of these standards. Chapter 5 of the FEIS 
outlines a number of other initiatives across government that could 
ameliorate the environmental impacts of motor vehicle use, including 
the use of HD vehicles.

XII. Statutory and Executive Order Reviews

(1) Executive Order 12866: Regulatory Planning and Review

    Under section 3(f)(1) of Executive Order 12866 (58 FR 51735, 
October 4, 1993), this action is an ``economically significant 
regulatory action'' because it is likely to have an annual effect on 
the economy of $100 million or more. Accordingly, the agencies 
submitted this action to the Office of Management and Budget (OMB) for 
review under Executive Order 12866 and any changes made in response to 
OMB recommendations have been documented in the docket for this action.
    The agencies are also subject to Executive Order 13563 (76 FR 3821, 
January 21, 2011) and NHTSA is subject to the Department of 
Transportation's Regulatory Policies and Procedures. These final rules 
are also significant within the meaning of the DOT Regulatory Policies 
and Procedures. Executive Order 12866 additionally requires NHTSA to 
submit this action to OMB for review and document any changes made in 
response to OMB recommendations.
    In addition, the agencies prepared an analysis of the potential 
costs, fuel savings, and benefits associated with this action. This 
analysis is contained in the Regulatory Impact Analysis, which is 
available in the docket for these rules and at the docket Internet 
address listed under ADDRESSES above and is briefly summarized in Table 
XII-1.

[[Page 57365]]

   Table XII-1--Estimated Lifetime Discounted Costs, Benefits, and Net
           Benefits for 2014-2018 Model Year HD Vehicles a, b
                             [Billion 2009$]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
              Lifetime Present Value \c\--3% Discount Rate
------------------------------------------------------------------------
Program Costs........................................               $8.1
Fuel Savings.........................................                 50
Benefits.............................................                7.3
Net Benefits \d\.....................................                 49
------------------------------------------------------------------------
                 Annualized Value \e\--3% Discount Rate
------------------------------------------------------------------------
Annualized Costs.....................................                0.4
Fuel Savings.........................................                2.2
Annualized Benefits..................................                0.4
Net Benefits \d\.....................................                2.2
------------------------------------------------------------------------
              Lifetime Present Value \c\--7% Discount Rate
------------------------------------------------------------------------
Program Costs........................................                8.1
Fuel Savings.........................................                 34
Benefits.............................................                6.7
Net Benefits \d\.....................................                $33
------------------------------------------------------------------------
                 Annualized Value \e\--7% Discount Rate
------------------------------------------------------------------------
Annualized Costs.....................................                0.6
Fuel Savings.........................................                2.6
Annualized Benefits..................................                0.5
Net Benefits \d\.....................................                2.5
------------------------------------------------------------------------
Notes:
\a\ The agencies estimated the benefits associated with four different
  values of a one ton CO2 reduction (model average at 2.5% discount
  rate, 3%, and 5%; 95th percentile at 3%), which each increase over
  time. For the purposes of this overview presentation of estimated
  costs and benefits, however, we are showing the benefits associated
  with the marginal value deemed to be central by the interagency
  working group on this topic: the model average at 3% discount rate, in
  2009 dollars. Section VIII.F provides a complete list of values for
  the 4 estimates.
\b\ Note that net present value of reduced GHG emissions is calculated
  differently than other benefits. The same discount rate used to
  discount the value of damages from future emissions (SCC at 5, 3, and
  2.5 percent) is used to calculate net present value of SCC for
  internal consistency. Refer to Section VIII.F for more detail.
\c\ Present value is the total, aggregated amount that a series of
  monetized costs or benefits that occur over time is worth now (in year
  2009 dollar terms), discounting future values to the present.
\d\ Net benefits reflect the fuel savings plus benefits minus costs.
\e\ The annualized value is the constant annual value through a given
  time period (2012 through 2050 in this analysis) whose summed present
  value equals the present value from which it was derived.

(2) National Environmental Policy Act

    Under NEPA, a Federal agency must prepare an Environmental Impact 
Statement (EIS) on proposed actions that could significantly impact the 
quality of the human environment. The requirement is designed to serve 
three major functions: (1) To provide the decisionmaker(s) with a 
detailed description of the potential environmental impacts of a 
proposed action prior to its adoption, (2) to rigorously explore and 
evaluate all reasonable alternatives, and (3) to inform the public of, 
and allow comment on, such efforts.
    In addition, the CEQ regulations emphasize agency cooperation early 
in the NEPA process and allow a lead agency (in this case, NHTSA) to 
request the assistance of other agencies that either have jurisdiction 
by law or have special expertise regarding issues considered in an 
EIS.\581\ At NHTSA's request, both EPA and the Federal Motor Carrier 
Safety Administration (FMCSA) agreed to act as cooperating agencies in 
the preparation of the EIS. EPA has special expertise in climate change 
and air quality, and FMCSA has special expertise regarding HD vehicles.
---------------------------------------------------------------------------

    \581\ 40 CFR 1501.6.
---------------------------------------------------------------------------

    NHTSA, in cooperation with EPA and FMCSA, prepared a DEIS, 
solicited public comments in writing and in public hearings, and 
prepared an FEIS responding to those comments. Specifically, in June 
2010, NHTSA published a Notice of Intent to prepare an EIS for proposed 
HD fuel efficiency standards.\582\ See 40 CFR 1501.7. On October 29, 
2010, EPA issued its Notice of Availability of the DEIS,\583\ 
triggering a public comment period. See 40 CFR 1506.10. The public was 
invited to submit written comments on the DEIS until January 3, 2011. 
NHTSA mailed (both electronically and through regular U.S. mail) copies 
of the DEIS to interested parties, including federal, state, and local 
officials and agencies; elected officials; environmental and public 
interest groups; Native American tribes; and other interested 
individuals. NHTSA and EPA held two hearings on the proposed rules and 
the EIS, the first on November 15, 2010 in Chicago, Illinois, and the 
second on November 18, 2010 in Cambridge, Massachusetts.
---------------------------------------------------------------------------

    \582\ See Notice of Intent to Prepare an Environmental Impact 
Statement for New Medium- and Heavy-Duty Fuel Efficiency Improvement 
Program, 75 FR 33565 (June 14, 2010).
    \583\ Environmental Impact Statements; Notice of Availability, 
75 FR 66756 (Oct. 29, 2010); NHTSA also published a separate Notice 
of Availability describing the program in greater detail, 75 FR 
68312 (Nov. 5, 2010).
---------------------------------------------------------------------------

    NHTSA received 3,048 written comments to the DEIS and the NPRM. The 
transcript from the public hearing and written comments submitted to 
NHTSA are part of the administrative record and are available on the 
Federal Docket, which can be found online at http://www.regulations.gov, Reference Docket No. NHTSA-2010-0079. NHTSA 
reviewed and analyzed all comments received during the public comment 
period and revised the FEIS in response

[[Page 57366]]

to comments on the EIS where appropriate.\584\
---------------------------------------------------------------------------

    \584\ The agency also changed the FEIS as a result of updated 
information that became available after issuance of the DEIS.
---------------------------------------------------------------------------

    On June 20, 2011, NHTSA submitted the FEIS to EPA. NHTSA also 
mailed (both electronically and through regular U.S. mail) the FEIS to 
interested parties and posted the FEIS on its Web site, http://www.nhtsa.gov/fuel-economy. On June 24, 2011, EPA published a Notice of 
Availability of the FEIS in the Federal Register.\585\
---------------------------------------------------------------------------

    \585\ 76 FR 37111 (June 24, 2011).
---------------------------------------------------------------------------

    The FEIS analyzes and discloses the potential environmental impacts 
of the proposed HD fuel efficiency standards pursuant to the National 
Environmental Policy Act (NEPA), the CEQ regulations implementing NEPA, 
DOT Order 5610.1C, and NHTSA regulations.\586\ The FEIS compares the 
potential environmental impacts of alternative standards considered by 
NHTSA for the final rule. It also analyzes direct, indirect, and 
cumulative impacts and analyzes impacts in proportion to their 
significance. See the FEIS and the FEIS Summary for a discussion of the 
environmental impacts analyzed. Docket No. NHTSA-2011-0079.
---------------------------------------------------------------------------

    \586\ NEPA is codified at 42 U.S.C. 4321-4347. CEQ NEPA 
implementing regulations are codified at 40 Code of Federal 
Regulations (CFR) Parts 1500-1508. NHTSA NEPA implementing 
regulations are codified at 49 CFR part 520.
---------------------------------------------------------------------------

    The standards adopted in this Final Rule have been informed by 
analyses contained in the Medium- and Heavy-Duty Fuel Efficiency 
Improvement Program, Final Environmental Impact Statement, Docket No. 
NHTSA-2010-0079 (FEIS). For purposes of this rulemaking, the agency 
referred to an extensive compilation of technical and policy documents 
available in NHTSA's EIS/Rulemaking docket and EPA's docket. NHTSA's 
EIS and rulemaking docket and EPA's rulemaking docket can be found 
online at http://www.regulations.gov, Reference Docket Nos.: NHTSA-
2010-0079 (EIS and Rulemaking) and EPA-HQ-OAR-2010-0162 (EPA 
Rulemaking).
    Based on the foregoing, the agency concludes that the environmental 
analysis and public involvement process complies with NEPA implementing 
regulations issued by CEQ, DOT Order 5610.1C, and NHTSA regulations.
(a) Clean Air Act (CAA)
    The CAA (42 U.S.C. Sec.  7401) is the primary Federal legislation 
that addresses air quality. Under the authority of the CAA and 
subsequent amendments, the EPA has established National Ambient Air 
Quality Standards (NAAQS) for six criteria pollutants, which are 
relatively commonplace pollutants that can accumulate in the atmosphere 
as a result of normal levels of human activity. The EPA is required to 
review each NAAQS every five years and to change the standards if 
warranted by new scientific information.
    The air quality of a geographic region is usually assessed by 
comparing the levels of criteria air pollutants found in the atmosphere 
to the applicable NAAQS. Concentrations of criteria pollutants within 
the air mass of a region are measured in parts of a pollutant per 
million parts of air (ppm) or in micrograms of a pollutant per cubic 
meter ([mu]g/m3) of air present in repeated air samples taken at 
designated monitoring locations. These ambient concentrations of each 
criteria pollutant are compared to the permissible levels specified by 
the NAAQS in order to assess whether the region's air quality attains 
the standard.
    When the measured concentrations of a criteria pollutant within a 
geographic region are below those permitted by the NAAQS, the region is 
designated by the EPA as an attainment area for that pollutant, while 
regions where concentrations of criteria pollutants exceed the NAAQS 
are called nonattainment areas (NAAs). Former NAAs that have attained 
the NAAQS are designated as maintenance areas. Each NAA is required to 
develop and implement a State Implementation Plan (SIP), which 
documents how the region will reach attainment levels within time 
periods specified in the CAA. In maintenance areas, the SIP documents 
how the State intends to maintain compliance with the NAAQS. When EPA 
changes a NAAQS, States must revise their SIPs to address how they will 
attain the new standard.
    Section 176(c) of the CAA prohibits Federal agencies from taking 
actions in nonattainment or maintenance areas that do not ``conform'' 
to the State Implementation Plan (SIP). The purpose of this conformity 
requirement is to ensure that Federal activities do not interfere with 
meeting the emissions targets in the SIPs, do not cause or contribute 
to new violations of the NAAQS, and do not impede the ability to attain 
or maintain the NAAQS. The EPA has issued two sets of regulations to 
implement CAA Section 176(c):
     The Transportation Conformity Rules (40 CFR part 93, 
subpart A), which apply to transportation plans, programs, and projects 
funded or approved under U.S.C. Title 23 or the Federal Transit Laws 
(49 U.S.C. chapter 53). Projects funded by the Federal Highway 
Administration (FHWA) or the Federal Transit Administration (FTA) 
usually are subject to transportation conformity. See 40 CFR 93.102.
     The General Conformity Rules (40 CFR part 93, subpart B) 
apply to all other federal actions not covered under transportation 
conformity. The General Conformity Rule established emissions 
thresholds, or de minimis levels, for use in evaluating the conformity 
of a project. If the net emissions increases attributable to the 
project are less than these thresholds, then the project is presumed to 
conform and no further conformity evaluation is required. If the 
emissions increases exceed any of these thresholds, then a conformity 
determination is required. The conformity determination can entail air 
quality modeling studies, consultation with EPA and state air quality 
agencies, and commitments to revise the SIP or to implement measures to 
mitigate air quality impacts.
    The final fuel consumption standards and associated program 
activities are not funded or approved under U.S.C. Title 23 or the 
Federal Transit Act. Further, NHTSA's HD Fuel Efficiency Improvement 
Program is not a highway or transit project funded or approved by FHWA 
or FTA. Accordingly, the standards and associated rulemakings are not 
subject to transportation conformity.
    Under the General Conformity Rule, a conformity determination is 
required where a Federal action would result in total direct and 
indirect emissions of a criteria pollutant or precursor equaling or 
exceeding the rates specified in 40 CFR 93.153(b)(1) and (2) for 
nonattainment and maintenance areas. As explained below, NHTSA's action 
results in neither direct nor indirect emissions as defined in 40 CFR 
93.152.
    The General Conformity Rule defines direct emissions as those of 
``a criteria pollutant or its precursors that are caused or initiated 
by the Federal action and originate in a nonattainment or maintenance 
area and occur at the same time and place as the action and are 
reasonably foreseeable.'' 40 CFR 93.152. Because NHTSA's action only 
sets fuel consumption standards for HD vehicles, it causes no direct 
emissions within the meaning of the General Conformity Rule.
    Indirect emissions under the General Conformity Rule include 
emissions or precursors: (1) That are caused or initiated by the 
Federal action and originate in the same nonattainment or maintenance 
area but occur at a different time or place than the action; (2) that 
are reasonably foreseeable; (3)

[[Page 57367]]

that the agency can practically control; and (4) for which the agency 
has continuing program responsibility. 40 CFR 93.152. Each element of 
the definition must be met to qualify as an indirect emission. NHTSA 
has determined that, for the purposes of general conformity, emissions 
that occur as a result of the fuel consumption standards are not caused 
by NHTSA's action, but rather occur due to subsequent activities that 
the agency cannot practically control. ``[E]ven if a Federal licensing, 
rulemaking, or other approving action is a required initial step for a 
subsequent activity that causes emissions, such initial steps do not 
mean that a Federal agency can practically control any resulting 
emissions'' (75 FR 17254, 17260; 40 CFR 93.152). NHTSA cannot control 
vehicle manufacturers' production of HD vehicles and consumer 
purchasing and driving behavior. For the purposes of analyzing the 
environmental impacts of this action under NEPA, NHTSA has made 
assumptions regarding the technologies manufacturers will install and 
how companies will react to increased fuel efficiency standards. 
Specifically, NHTSA's NEPA analysis predicted increases in air toxic 
and criteria pollutants to occur in some nonattainment areas under 
certain alternatives based on assumptions about the use of APUs and the 
rebound effect. For example, NHTSA's NEPA analysis assumes that some 
manufacturers will install anti-idling technologies (including APUs) on 
some vehicle classes to meet the requirements of the program and that 
drivers' subsequent use of those APUs will result in an increase in 
some criteria pollutants. However, neither NHTSA's nor EPA's rules 
mandate this specific manufacturer decision or driver behavior--the 
program does not require that manufacturers install APUs to meet the 
requirements of the rule, and it does not require drivers to use anti-
idling technologies instead of, for example, shutting off all power 
when parked. Similarly, NHTSA's NEPA analysis assumes a rebound effect, 
wherein the standards could create an incentive for additional vehicle 
use by reducing the cost of fuel consumed per mile driven. This rebound 
effect is an estimate of how NHTSA assumes some drivers will react to 
the rule and is useful for estimating the costs and benefits of the 
rule, but the agency does not have the statutory authority, or the 
program responsibility, to control, among other items discussed above, 
the actual vehicle miles traveled by drivers. Accordingly, changes in 
any emissions that result from NHTSA's HD vehicle Fuel Efficiency 
Improvement Program are not changes that the agency can practically 
control; therefore, this action causes no indirect emissions and a 
general conformity determination is not required.
(b) National Historic Preservation Act (NHPA)
    The NHPA (16 U.S.C. 470) sets forth government policy and 
procedures regarding ``historic properties''--that is, districts, 
sites, buildings, structures, and objects included in or eligible for 
the National Register of Historic Places (NRHP). See also 36 CFR part 
800. Section 106 of the NHPA requires federal agencies to ``take into 
account'' the effects of their actions on historic properties. The 
agency concludes that the NHPA is not applicable to NHTSA's Decision 
because it does not directly involve historic properties. The agency 
has, however, conducted a qualitative review of the related direct, 
indirect, and cumulative impacts, positive or negative, of the 
alternatives on potentially affected resources, including historic and 
cultural resources. See Section 4.5 of the FEIS.
(c) Executive Order 12898 (Environmental Justice)
    Under Executive Order 12898, Federal agencies are required to 
identify and address any disproportionately high and adverse human 
health or environmental effects of its programs, policies, and 
activities on minority populations and low-income populations. NHTSA 
complied with this order by identifying and addressing the potential 
effects of the alternatives on minority and low-income populations in 
Sections 3.6 and 4.6 of the FEIS, where the agency set forth a 
qualitative analysis of the cumulative effects of the alternatives on 
these populations.
(d) Fish and Wildlife Conservation Act (FWCA)
    The FWCA (16 U.S.C. Sec.  2900) provides financial and technical 
assistance to States for the development, revision, and implementation 
of conservation plans and programs for nongame fish and wildlife. In 
addition, the Act encourages all Federal agencies and departments to 
utilize their authority to conserve and to promote conservation of 
nongame fish and wildlife and their habitats. The agency concludes that 
the FWCA is not applicable to NHTSA's Decision because it does not 
directly involve fish and wildlife.
(e) Coastal Zone Management Act (CZMA)
    The Coastal Zone Management Act (16 U.S.C. 1450) provides for the 
preservation, protection, development, and (where possible) restoration 
and enhancement of the nation's coastal zone resources. Under the 
statute, States are provided with funds and technical assistance in 
developing coastal zone management programs. Each participating State 
must submit its program to the Secretary of Commerce for approval. Once 
the program has been approved, any activity of a Federal agency, either 
within or outside of the coastal zone, that affects any land or water 
use or natural resource of the coastal zone must be carried out in a 
manner that is consistent, to the maximum extent practicable, with the 
enforceable policies of the State's program.
    The agency concludes that the CZMA is not applicable to NHTSA's 
Decision because it does not involve an activity within, or outside of, 
the nation's coastal zones. The agency has, however, conducted a 
qualitative review of the related direct, indirect, and cumulative 
impacts, positive or negative, of the alternatives on potentially 
affected resources, including coastal zones. See Section 4.5 of the 
FEIS.
(f) Endangered Species Act (ESA)
    Under Section 7(a)(2) of the Endangered Species Act (ESA) federal 
agencies must ensure that actions they authorize, fund, or carry out 
are ``not likely to jeopardize'' federally listed threatened or 
endangered species or result in the destruction or adverse modification 
of the designated critical habitat of these species. 16 U.S.C. 
1536(a)(2). If a federal agency determines that an agency action may 
affect a listed species or designated critical habitat, it must 
initiate consultation with the appropriate Service--the U.S. Fish and 
Wildlife Service (FWS) of the Department of the Interior and/or 
National Oceanic and Atmospheric Administration's National Marine 
Fisheries Service (NOAA Fisheries Service) of the Department of 
Commerce, depending on the species involved--in order to ensure that 
the action is not likely to jeopardize the species or destroy or 
adversely modify designated critical habitat. See 50 CFR 402.14. Under 
this standard, the federal agency taking action evaluates the possible 
effects of its action and determines whether to initiate consultation. 
See 51 FR 19926, 19949 (Jun. 3, 1986).

[[Page 57368]]

    NHTSA received one comment to the Scoping notice for the HD program 
indicating that the agency should engage in consultation under Section 
7 of the ESA when analyzing the overall impact of GHG emissions and 
other air pollutants. NHTSA has reviewed applicable ESA regulations, 
case law, guidance, and rulings in assessing the potential for impacts 
to threatened and endangered species from the HD fuel efficiency 
standards. Consistent with NHTSA's determination under the agency's 
most recent light-duty fuel economy rule, NHTSA believes that the 
agency's action, which will result in nationwide fuel savings and, 
consequently, emissions reductions from what would otherwise occur in 
the absence of the agency's action, does not require consultation with 
NOAA Fisheries Service or the FWS under Section 7(a)(2) of the ESA. For 
discussion of the agency's rationale in the context of the CAFE 
program, see Appendix G of the FEIS for MYs 2012-2016, available at: 
http://www.nhtsa.gov/fuel-economy. Accordingly, NHTSA has concluded its 
review of this action under Section 7 of the ESA.
(g) Floodplain Management (Executive Order 11988 & DOT Order 5650.2)
    These Orders require Federal agencies to avoid the long- and short-
term adverse impacts associated with the occupancy and modification of 
floodplains, and to restore and preserve the natural and beneficial 
values served by floodplains. Executive Order 11988 also directs 
agencies to minimize the impact of floods on human safety, health and 
welfare, and to restore and preserve the natural and beneficial values 
served by floodplains through evaluating the potential effects of any 
actions the agency may take in a floodplain and ensuring that its 
program planning and budget requests reflect consideration of flood 
hazards and floodplain management. DOT Order 5650.2 sets forth DOT 
policies and procedures for implementing Executive Order 11988. The DOT 
Order requires that the agency determine if a proposed action is within 
the limits of a base floodplain, meaning it is encroaching on the 
floodplain, and whether this encroachment is significant. If 
significant, the agency is required to conduct further analysis of the 
proposed action and any practicable alternatives. If a practicable 
alternative avoids floodplain encroachment, then the agency is required 
to implement it.
    In this rulemaking, the agency is not occupying, modifying and/or 
encroaching on floodplains. The agency, therefore, concludes that the 
Orders are not applicable to NHTSA's Decision. The agency has, however, 
conducted a review of the alternatives on potentially affected 
resources, including floodplains. See Section 4.5 of the FEIS.
(h) Preservation of the Nation's Wetlands (Executive Order 11990 & DOT 
Order 5660.1a)
    These Orders require Federal agencies to avoid, to the extent 
possible, undertaking or providing assistance for new construction 
located in wetlands unless the agency head finds that there is no 
practicable alternative to such construction and that the proposed 
action includes all practicable measures to minimize harms to wetlands 
that may result from such use. Executive Order 11990 also directs 
agencies to take action to minimize the destruction, loss or 
degradation of wetlands in ``conducting Federal activities and programs 
affecting land use, including but not limited to water and related land 
resources planning, regulating, and licensing activities.'' DOT Order 
5660.1a sets forth DOT policy for interpreting Executive Order 11990 
and requires that transportation projects ``located in or having an 
impact on wetlands'' should be conducted to assure protection of the 
Nation's wetlands. If a project does have a significant impact on 
wetlands, an EIS must be prepared.
    The agency is not undertaking or providing assistance for new 
construction located in wetlands. The agency, therefore, concludes that 
these Orders do not apply to NHTSA's Decision. The agency has, however, 
conducted a review of the alternatives on potentially affected 
resources, including wetlands. See Section 4.5 of the FEIS.
(i) Migratory Bird Treaty Act (MBTA), Bald and Golden Eagle Protection 
Act (BGEPA), Executive Order 13186
    The MBTA provides for the protection of migratory birds that are 
native to the United States by making it illegal for anyone to pursue, 
hunt, take, attempt to take, kill, capture, collect, possess, buy, 
sell, trade, ship, import, or export any migratory bird covered under 
the statute. The statute prohibits both intentional and unintentional 
acts. Therefore, the statute is violated if an agency acts in a manner 
that harms a migratory bird, whether it was intended or not. See, e.g., 
United States v. FMC Corp., 572 F.2d 902 (2nd Cir. 1978).
    The BGEPA (16 U.S.C. 668) prohibits any form of possession or 
taking of both bald and golden eagles. Under the BGEPA, violators are 
subject to criminal and civil sanctions as well as an enhanced penalty 
provision for subsequent offenses.
    Executive Order 13186, ``Responsibilities of Federal Agencies to 
Protect Migratory Birds,'' helps to further the purposes of the MBTA by 
requiring a Federal agency to develop a Memorandum of Understanding 
(MOU) with the Fish and Wildlife Service when it is taking an action 
that has (or is likely to have) a measurable negative impact on 
migratory bird populations.
    The agency concludes that the MBTA, BGEPA, and Executive Order 
13186 do not apply to NHTSA's Decision because there is no disturbance 
and/or take involved in NHTSA's Decision.
(j) Department of Transportation Act (Section 4(f))
    Section 4(f) of the Department of Transportation Act of 1966 (49 
U.S.C. 303), as amended by Public Law 109-59, is designed to preserve 
publicly owned parklands, waterfowl and wildlife refuges, and 
significant historic sites. Specifically, Section 4(f) of the 
Department of Transportation Act provides that DOT agencies cannot 
approve a transportation program or project that requires the use of 
any publicly owned land from a significant public park, recreation 
area, or wildlife and waterfowl refuge, or any land from a significant 
historic site, unless a determination is made that:
     There is no feasible and prudent alternative to the use of 
land, and
     The program or project includes all possible planning to 
minimize harm to the property resulting from use, or
     A transportation use of Section 4(f) property results in a 
de minimis impact.
    The agency concludes that the Section 4(f) is not applicable to 
NHTSA's Decision because this rulemaking does not require the use of 
any publicly owned land. For a more detailed discussion, please see 
Section 3.1 of the FEIS.

(3) Paperwork Reduction Act

    The information collection requirements in these rules have been 
submitted for approval to OMB under the Paperwork Reduction Act, 44 
U.S.C. 3501 et seq. The information collection requirements are not 
enforceable until OMB approves them.
    The agencies propose to collect information to ensure compliance 
with the provisions in these rules. This includes a variety of testing, 
reporting and recordkeeping requirements for vehicle manufacturers. 
Section 208(a) of the CAA requires that vehicle manufacturers provide 
information the Administrator may reasonably require to determine 
compliance with the

[[Page 57369]]

regulations; submission of the information is therefore mandatory. We 
will consider confidential all information meeting the requirements of 
section 208(c) of the CAA.
    It is estimated that this collection affects approximately 34 
engine and vehicle manufacturers. The information that is subject to 
this collection is collected whenever a manufacturer applies for a 
certificate of conformity. Under section 206 of the CAA (42 U.S.C. 
7521), a manufacturer must have a certificate of conformity before a 
vehicle or engine can be introduced into commerce.
    The burden to the manufacturers affected by these rules has a range 
based on the number of engines and vehicles a manufacturer produces. 
The total estimated burden associated with these rules is 58,064 hours 
annually (See Table XII-2). This estimated burden for engine and 
vehicle manufacturers is a total estimate for new reporting 
requirements. Burden is defined at 5 CFR 1320.3(b).

    Table XII-2--Burden for Reporting and Recordkeeping Requirements
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Number of Affected Manufacturers......................                34
Annual Labor Hours for Each Manufacturer to Prepare               Varies
 and Submit Required Information......................
Total Annual Information Collection Burden............      58,064 Hours
------------------------------------------------------------------------

    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR part 9. When this ICR is approved by 
OMB, the agency will publish a technical amendment to 40 CFR part 9 in 
the Federal Register to display the OMB control number for the approved 
information collection requirements contained in this final action.

(4) Regulatory Flexibility Act

(a) Overview
    The Regulatory Flexibility Act generally requires an agency to 
prepare a regulatory flexibility analysis of any rule subject to notice 
and comment rulemaking requirements under the Administrative Procedure 
Act or any other statute unless the agency certifies that the rule will 
not have a significant economic impact on a substantial number of small 
entities. Small entities include small businesses, small organizations, 
and small governmental jurisdictions.
    For purposes of assessing the impacts of these rules on small 
entities, small entity is defined as: (1) A small business as defined 
by SBA regulations at 13 CFR 121.201; (2) a small governmental 
jurisdiction that is a government of a city, county, town, school 
district or special district with a population of less than 50,000; and 
(3) a small organization that is any not-for-profit enterprise which is 
independently owned and operated and is not dominant in its field.
(b) Summary of Potentially Affected Small Entities
    The agencies have not conducted a Regulatory Flexibility Analysis 
for this action because the agencies are certifying that these rules 
would not have a significant economic impact on a substantial number of 
small entities. As proposed, the agencies are deferring standards for 
manufacturers meeting SBA's definition of small business as described 
in 13 CFR 121.201 due to the extremely small fuel savings and emissions 
contribution of these entities, and the short lead time to develop 
these rules, especially with our expectation that the program would 
need to be structured differently for them (which would require more 
time). The agencies are instead envisioning fuel consumption and GHG 
emissions standards for these entities as part of a future regulatory 
action. This includes small entities in several distinct categories of 
businesses for heavy-duty engines and vehicles: chassis manufacturers, 
combination tractor manufacturers, and alternative fuel engine 
converters.
    Based on a preliminary assessment, the agencies have identified a 
total of about 17 engine manufacturers, 3 complete pickup truck and van 
manufacturers, 11 combination tractor manufacturers and 43 heavy-duty 
chassis manufacturers. Notably, several of these manufacturers produce 
vehicles in more than just one regulatory category (HD pickup trucks/
vans, combination tractors, or vocational vehicles (i.e. heavy-duty 
chassis manufacturers)). Based on the types of vehicles they 
manufacture, these companies, however, would be subject to slightly 
different testing and reporting requirements. Taking this feature of 
the heavy-duty trucking sector into account, the agencies estimate that 
although there are fewer than 30 manufacturers covered by the program, 
there are close to 60 divisions within these companies that will be 
subject to the final regulations. Of these, about 15 entities fit the 
SBA criteria of a small business. There are approximately three engine 
converters, two tractor manufacturers, and ten heavy-duty chassis 
manufacturers in the heavy-duty engine and vehicle market that are 
small businesses. (No major heavy-duty engine manufacturers, heavy-duty 
chassis manufacturers, or tractor manufacturers meet the small-entity 
criteria as defined by SBA). The agencies estimate that these small 
entities comprise less than 0.35 percent of the total heavy-duty 
vehicle sales in the United States, and therefore the deferment will 
have a negligible impact on the fuel consumption and GHG emissions 
reductions from the final standards.
    To ensure that the agencies are aware of which companies are being 
deferred, the agencies are requiring that such entities submit a 
declaration to the agencies containing a detailed written description 
of how that manufacturer qualifies as a small entity under the 
provisions of 13 CFR 121.201. Some small entities, such as heavy-duty 
tractor and chassis manufacturers, are not currently covered under 
criteria pollutant motor vehicle emissions regulations. Small engine 
entities are currently covered by a number of EPA motor vehicle 
emission regulations, and they routinely submit information and data on 
an annual basis as part of their compliance responsibilities. Because 
such entities are not automatically exempted from other EPA regulations 
for heavy-duty engines and vehicles, absent such a declaration, EPA 
would assume that the entity was subject to the greenhouse gas control 
requirements in this program. The declaration to the agencies will need 
to be submitted at the time of either engine or vehicle emissions 
certification under the HD highway engine program for criteria 
pollutants. The agencies expect that the additional paperwork burden 
associated with completing and submitting a small entity declaration to 
gain deferral from the final GHG and fuel consumption standards will be 
negligible and easily done in the context of other routine submittals 
to the agencies. However, the

[[Page 57370]]

agencies have accounted for this cost with a nominal estimate included 
in the Information Collection Request completed under the Paperwork 
Reduction Act. Additional information can be found in the Paperwork 
Reduction Act discussion in Section 0Paperwork Reduction Act. Based on 
this, the agencies are certifying that the rules will not have a 
significant economic impact on a substantial number of small entities.

(5) Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, the 
agencies generally must prepare a written statement, including a cost-
benefit analysis, for proposed and final rules with ``Federal 
mandates'' that may result in expenditures to State, local, and tribal 
governments, in the aggregate, or to the private sector, of $100 
million or more in any one year. Before promulgating a rule for which a 
written statement is needed, section 205 of the UMRA generally requires 
the agencies to identify and consider a reasonable number of regulatory 
alternatives and adopt the least costly, most cost-effective or least 
burdensome alternative that achieves the objectives of the rule. The 
provisions of section 205 do not apply when they are inconsistent with 
applicable law. Moreover, section 205 allows the agencies to adopt an 
alternative other than the least costly, most cost-effective or least 
burdensome alternative if the Administrator (of either agency) 
publishes with the final rule an explanation why that alternative was 
not adopted.
    Before the agencies establish any regulatory requirements that may 
significantly or uniquely affect small governments, including tribal 
governments, they must have developed under section 203 of the UMRA a 
small government agency plan. The plan must provide for notifying 
potentially affected small governments, enabling officials of affected 
small governments to have meaningful and timely input in the 
development of EPA and NHTSA regulations with significant Federal 
intergovernmental mandates, and informing, educating, and advising 
small governments on compliance with the regulatory requirements.
    These rules contain no Federal mandates (under the regulatory 
provisions of Title II of the UMRA) for State, local, or tribal 
governments. The rules impose no enforceable duty on any State, local 
or tribal governments. The agencies have determined that these rules 
contain no regulatory requirements that might significantly or uniquely 
affect small governments. The agencies have determined that these rules 
contain a Federal mandate that may result in expenditures of $134 
million or more for the private sector in any one year. The agencies 
believe that the program represents the least costly, most cost-
effective approach to achieve the statutory requirements of the rules. 
Section VIII.L, above, explains why the agencies believe that the fuel 
savings that will result from these rules will lead to lower prices 
economy-wide, improving U.S. international competitiveness. The costs 
and benefits associated with the program are discussed in more detail 
above in Section VIII and in the Regulatory Impact Analysis, as 
required by the UMRA.
    Table XII-1, above, presents the rule-related benefits, fuel 
savings, costs and net benefits in both present value terms and in 
annualized terms. In both cases, the discounted values are based on an 
underlying time varying stream of cost and benefit values that extend 
into the future (2012 through 2050). The distribution of each monetized 
economic impact over time can be viewed in the RIA that accompanies 
these rules.
    Present values represent the total amount that a stream of 
monetized costs/benefits/net benefits that occur over time are worth 
now (in year 2009 dollar terms for this analysis), accounting for the 
time value of money by discounting future values using either a 3 or 7 
percent discount rate, per OMB Circular A-4 guidance. An annualized 
value takes the present value and converts it into a constant stream of 
annual values through a given time period (2012 through 2050 in this 
analysis) and thus averages (in present value terms) the annual values. 
The present value of the constant stream of annualized values equals 
the present value of the underlying time varying stream of values. The 
ratio of benefits to costs is identical whether it is measured with 
present values or annualized values.
    It is important to note that annualized values cannot simply be 
summed over time to reflect total costs/benefits/net benefits; they 
must be discounted and summed. Additionally, the annualized value can 
vary substantially from the time varying stream of cost/benefit/net 
benefit values that occur in any given year.

(6) Executive Order 13132 (Federalism)

    This action does not have federalism implications. It will not have 
substantial direct effects on the States, on the relationship between 
the national government and the States, or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132. These rules will apply to 
manufacturers of motor vehicles and not to state or local governments. 
Thus, Executive Order 13132 does not apply to this action. Although 
section 6 of Executive Order 13132 does not apply to this action, the 
agencies did consult with representatives of state governments in 
developing this action.
    NHTSA notes that EPCA contains a provision (49 U.S.C. 32919(a)) 
that expressly preempts any State or local government from adopting or 
enforcing a law or regulation related to fuel economy standards or 
average fuel economy standards for automobiles covered by an average 
fuel economy standard under 49 U.S.C. Chapter 329. However, commercial 
medium- and heavy-duty on-highway vehicles and work trucks are not 
``automobiles,'' as defined in 49 U.S.C. 32901(a)(3). Accordingly, 
NHTSA has tentatively concluded that EPCA's express preemption 
provision would not reach the fuel efficiency standards to be 
established in this rulemaking.
    NHTSA also considered the issue of implied or conflict preemption. 
The possibility of such preemption is dependent upon there being an 
actual conflict between a standard established by NHTSA in this 
rulemaking and a State or local law or regulation. See Spriestma v. 
Mercury Marine, 537 U.S. 51, 64-65 (2002). At present, NHTSA has no 
knowledge of any State or local law or regulation that would actually 
conflict with one of the fuel efficiency standards being established in 
this rulemaking.

(7) Executive Order 13175 (Consultation and Coordination With Indian 
Tribal Governments)

    These final rules do not have tribal implications, as specified in 
Executive Order 13175 (65 FR 67249, November 9, 2000). These rules will 
be implemented at the Federal level and impose compliance costs only on 
vehicle manufacturers. Tribal governments would be affected only to the 
extent they purchase and use regulated vehicles. Thus, Executive Order 
13175 does not apply to these rules.

[[Page 57371]]

(8) Executive Order 13045: ``Protection of Children From Environmental 
Health Risks and Safety Risks''

    This action is subject to Executive Order 13045 (62 FR 19885, April 
23, 1997) because it is an economically significant regulatory action 
as defined by Executive Order 12866, and the agencies believe that the 
environmental health or safety risk addressed by this action may have a 
disproportionate effect on children. A synthesis of the science and 
research regarding how climate change may affect children and other 
vulnerable subpopulations is contained in the Technical Support 
Document for Endangerment or Cause or Contribute Findings for 
Greenhouse Gases under section 202(a) of the Clean Air Act, which can 
be found in the public docket for these rules.\587\ A summary of the 
analysis is presented below.
---------------------------------------------------------------------------

    \587\ See Endangerment TSD, Note 10, above.
---------------------------------------------------------------------------

    With respect to GHG emissions, the effects of climate change 
observed to date and projected to occur in the future include the 
increased likelihood of more frequent and intense heat waves. 
Specifically, EPA's analysis of the scientific assessment literature 
has determined that severe heat waves are projected to intensify in 
magnitude, frequency, and duration over the portions of the United 
States where these events already occur, with potential increases in 
mortality and morbidity, especially among the young, elderly, and 
frail. EPA has estimated reductions in projected global mean surface 
temperatures as a result of reductions in GHG emissions associated with 
the final standards in this action (Section II). Children may receive 
benefits from reductions in GHG emissions because they are included in 
the segment of the population that is most vulnerable to extreme 
temperatures.
    For non-GHG pollutants, EPA has determined that climate change is 
expected to increase regional ozone pollution, with associated risks in 
respiratory infection, aggravation of asthma, and premature death. The 
directional effect of climate change on ambient PM levels remains 
uncertain. However, disturbances such as wildfires are increasing in 
the United States and are likely to intensify in a warmer future with 
drier soils and longer growing seasons. PM emissions from forest fires 
can contribute to acute and chronic illnesses of the respiratory 
system, particularly in children, including pneumonia, upper 
respiratory diseases, asthma and chronic obstructive pulmonary 
diseases.

(9) Executive Order 13211 (Energy Effects)

    This rulemaking is not a ``significant energy action'' as defined 
in Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 
28355, May 22, 2001) because it is not likely to have a significant 
adverse effect on the supply, distribution, or use of energy. In fact, 
these rules have a positive effect on energy supply and use. Because 
the final GHG emission and fuel consumption standards will result in 
significant fuel savings, these rules encourage more efficient use of 
fuels. Therefore, we have concluded that these rules are not likely to 
have any adverse energy effects. Our energy effects analysis is 
described above in Section VIII.I.

(10) National Technology Transfer Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, 12(d) (15 U.S.C. 272 note) 
directs the agencies to use voluntary consensus standards in its 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials, specifications, test methods, 
sampling procedures, and business practices) that are developed or 
adopted by voluntary consensus standards bodies. NTTAA directs the 
agencies to provide Congress, through OMB, explanations when the 
agencies decide not to use available and applicable voluntary consensus 
standards.
    For CO2, N2O, and CH4 emissions 
and fuel consumption from heavy-duty engines, the agencies will collect 
data over the same tests that are used for the heavy-duty highway 
engine program for criteria pollutants. This will minimize the amount 
of testing done by manufacturers, since manufacturers are already 
required to run these tests.
    For CO2, N2O, and CH4 emissions 
and fuel consumption from complete pickup trucks and vans, the agencies 
will collect data over the same tests that are used for EPA's heavy-
duty highway engine program for criteria pollutants and for the 
California Air Resources Board. This will minimize the amount of 
testing done by manufacturers, since manufacturers are already required 
to run these tests.
    For CO2 emissions and fuel consumption from heavy-duty 
combination tractors and vocational vehicles, the agencies will collect 
data through the use of a simulation model instead of a full-vehicle 
chassis dynamometer testing. This will minimize the amount of testing 
done by manufacturers. EPA's compliance assessment tool is based upon 
well-established engineering and physics principals that are the basis 
of general academic understanding in this area, and the foundation of 
any dynamic vehicle simulation model, including the models cited by 
ICCT in its study.\588\ Therefore, the EPA's compliance assessment tool 
satisfies the description of a consensus. For the evaluation of tire 
rolling resistance input to the model, EPA is finalizing to use the ISO 
28580 test, a voluntary consensus methodology. EPA is adopting several 
alternatives for the evaluation of aerodynamics which allows the 
industry to continue to use their own evaluation tools because EPA does 
not know of a single consensus standard available for heavy-duty truck 
aerodynamic evaluation.
---------------------------------------------------------------------------

    \588\ ICCT. ICCT Evaluation of Vehicle Simulation Tools. 2009.
---------------------------------------------------------------------------

    For air conditioning standards, EPA is finalizing a consensus 
methodology developed by the Society of Automotive Engineers (SAE).

(11) Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629, February 16, 1994) establishes 
federal executive policy on environmental justice. Its main provision 
directs federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the United States.
    With respect to GHG emissions, EPA has determined that these final 
rules will not have disproportionately high and adverse human health or 
environmental effects on minority or low-income populations because 
they increase the level of environmental protection for all affected 
populations without having any disproportionately high and adverse 
human health or environmental effects on any population, including any 
minority or low-income population. The reductions in CO2 and 
other GHGs associated with the standards will affect climate change

[[Page 57372]]

projections, and EPA has estimated reductions in projected global mean 
surface temperatures (Section VI). Within communities experiencing 
climate change, certain parts of the population may be especially 
vulnerable; these include the poor, the elderly, those already in poor 
health, the disabled, those living alone, and/or indigenous populations 
dependent on one or a few resources.\589\ In addition, the U.S. Climate 
Change Science Program stated as one of its conclusions: ``The United 
States is certainly capable of adapting to the collective impacts of 
climate change. However, there will still be certain individuals and 
locations where the adaptive capacity is less and these individuals and 
their communities will be disproportionally impacted by climate 
change.'' \590\ Therefore, these specific sub-populations may receive 
benefits from reductions in GHGs.
---------------------------------------------------------------------------

    \589\ See Endangerment TSD, Note 10, above.
    \590\ CCSP (2008) Analyses of the effects of global change on 
human health and welfare and human systems. A Report by the U.S. 
Climate Change Science Program and the Subcommittee on Global Change 
Research. [Gamble, J.L. (ed.), K.L. Ebi, F.G. Sussman, T.J. 
Wilbanks, (Authors)]. U.S. Environmental Protection Agency, 
Washington, DC, USA.
---------------------------------------------------------------------------

    For non-GHG co-pollutants such as ozone, PM2.5, and 
toxics, EPA has concluded that it is not practicable to determine 
whether there would be disproportionately high and adverse human health 
or environmental effects on minority and/or low income populations from 
these rules.

(12) Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. The agencies will submit a report containing these rules 
and other required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rules in the Federal Register. A Major rule 
cannot take effect until 60 days after it is published in the Federal 
Register. This action is a ``major rule'' as defined by 5 U.S.C. 
804(2). These rules will be effective November 14, 2011, sixty days 
after date of publication in the Federal Register.

(13) Privacy Act

    Anyone is able to search the electronic form of all comments 
received into any of our dockets by the name of the individual 
submitting the comment (or signing the comment, if submitted on behalf 
of an organization, business, labor union, etc.). You may review DOT's 
complete Privacy Act statement in the Federal Register (65 FR 19477-78, 
April 11, 2000) or you may visit http://www.dot.gov/privacy.html.

XIII. Statutory Provisions and Legal Authority

A. EPA

    Statutory authority for the vehicle controls in these rules is 
found in CAA section 202(a) (which requires EPA to establish standards 
for emissions of pollutants from new motor vehicles and engines which 
emissions cause or contribute to air pollution which may reasonably be 
anticipated to endanger public health or welfare), sections 202(d), 
203-209, 216, and 301 of the CAA, 42 U.S.C. 7521 (a), 7521 (d), 7522, 
7523, 7524, 7525, 7541, 7542, 7543, 7550, and 7601.

B. NHTSA

    Statutory authority for the fuel consumption standards in these 
rules is found in EISA section 103 (which authorizes a fuel efficiency 
improvement program, designed to achieve the maximum feasible 
improvement to be created for commercial medium- and heavy-duty on-
highway vehicles and work trucks, to include appropriate test methods, 
measurement metrics, standards, and compliance and enforcement 
protocols that are appropriate, cost-effective and technologically 
feasible) of the Energy Independence and Security Act of 2007, 49 
U.S.C. 32902(k).

List of Subjects

40 CFR Part 85

    Confidential business information, Imports, Labeling, Motor vehicle 
pollution, Reporting and recordkeeping requirements, Research, 
Warranties.

40 CFR Part 86

    Administrative practice and procedure, Confidential business 
information, Incorporation by reference, Labeling, Motor vehicle 
pollution, Reporting and recordkeeping requirements.

40 CFR Part 600

    Administrative practice and procedure, Electric power, Fuel 
economy, Incorporation by reference, Labeling, Reporting and 
recordkeeping requirements.

40 CFR Part 1033

    Administrative practice and procedure, Air pollution control.

40 CFR Parts 1036 and 1037

    Administrative practice and procedure, Air pollution control, 
Confidential business information, Environmental protection, 
Incorporation by reference, Labeling, Motor vehicle pollution, 
Reporting and recordkeeping requirements, Warranties.

40 CFR Part 1039

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Confidential business information, Imports, 
Labeling, Penalties, Reporting and recordkeeping requirements, 
Warranties.

40 CFR Parts 1065 and 1066

    Administrative practice and procedure, Air pollution control, 
Incorporation by reference, Reporting and recordkeeping requirements, 
Research.

40 CFR Part 1068

    Environmental protection, Administrative practice and procedure, 
Confidential business information, Imports, Incorporation by reference, 
Motor vehicle pollution, Penalties, Reporting and recordkeeping 
requirements, Warranties.

49 CFR Parts 523, 534, and 535

    Fuel economy.

Environmental Protection Agency

40 CFR Chapter I

    For the reasons set forth in the preamble, the Environmental 
Protection Agency is amending 40 CFR chapter I of the Code of Federal 
Regulations as follows:

PART 85--CONTROL OF AIR POLLUTION FROM MOBILE SOURCES

0
1. The authority citation for part 85 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

Subpart F--[Amended]

0
2. Section 85.525 is revised to read as follows:

Sec.  85.525  Applicable standards.

    To qualify for an exemption from the tampering prohibition, 
vehicles/engines that have been converted to operate on a different 
fuel must meet emission standards and related requirements as follows:
    (a) The modified vehicle/engine must meet the requirements that 
applied for

[[Page 57373]]

the OEM vehicle/engine, or the most stringent OEM vehicle/engine 
standards in any allowable grouping. Fleet average standards do not 
apply unless clean alternative fuel conversions are specifically listed 
as subject to the standards.
    (1) If the vehicle/engine was certified with a Family Emission 
Limit for NOX, NOX+HC, or particulate matter, as 
noted on the vehicle/engine emission control information label, the 
modified vehicle/engine may not exceed this Family Emission Limit.
    (2) Compliance with greenhouse gas emission standards is 
demonstrated as follows:
    (i) Subject to the following exceptions and special provisions, 
compliance with light-duty vehicle greenhouse gas emission standards is 
demonstrated by complying with the N2O and CH4 
standards and provisions set forth in 40 CFR 86.1818-12(f)(1) and the 
in-use CO2 exhaust emission standard set forth in 40 CFR 
86.1818-12(d) as determined by the OEM for the subconfiguration that is 
identical to the fuel conversion emission data vehicle (EDV).
    (A) If the OEM complied with the light-duty greenhouse gas 
standards using the fleet averaging option for N2O and 
CH4, as allowed under 40 CFR 86.1818-12(f)(2), the 
calculations of the carbon-related exhaust emissions require the input 
of grams/mile values for N2O and CH4, and you are 
not required to demonstrate compliance with the standalone 
CH4 and N2O standards.
    (B) If the OEM complied with alternate standards for N2O 
and/or CH4, as allowed under 40 CFR 86.1818-12(f)(3), you 
may demonstrate compliance with the same alternate standards.
    (C) If the OEM complied with the nitrous oxide (N2O) and 
methane (CH4) standards and provisions set forth in 40 CFR 
86.1818-12(f)(1) or 86.1818-12(f)(3), and the fuel conversion 
CO2 measured value is lower than the in-use CO2 
exhaust emission standard, you also have the option to convert the 
difference between the in-use CO2 exhaust emission standard 
and the fuel conversion CO2 measured value into GHG 
equivalents of CH4 and/or N2O, using 298 g 
CO2 to represent 1 g N2O and 25 g CO2 
to represent 1 g CH4. You may then subtract the applicable 
converted values from the fuel conversion measured values of 
CH4 and/or N2O to demonstrate compliance with the 
CH4 and/or N2O standards.
    (ii) Compliance with heavy-duty engine greenhouse gas emission 
standards is demonstrated by complying with the CO2, 
N2O, and CH4 standards (or FELs, as applicable) 
and provisions set forth in 40 CFR 1036.108 for the engine family that 
is represented by the fuel conversion emission data engine (EDE). If 
the fuel conversion CO2 measured value is lower than the 
CO2 standard (or FEL, as applicable), you have the option to 
convert the difference between the CO2 standard (or FEL, as 
applicable) and the fuel conversion CO2 measured value into 
GHG equivalents of CH4 and/or N2O, using 298 g/
hp-hr CO2 to represent 1 g/hp-hr N2O and 25 g/hp-
hr CO2 to represent 1 g/hp-hr CH4. You may then 
subtract the applicable converted values from the fuel conversion 
measured values of CH4 and/or N2O to demonstrate 
compliance with the CH4 and/or N2O standards (or 
FEL, as applicable).
    (3) Conversion systems for engines that would have qualified for 
chassis certification at the time of OEM certification may use those 
procedures, even if the OEM did not. Conversion manufacturers choosing 
this option must designate test groups using the appropriate criteria 
as described in this subpart and meet all vehicle chassis certification 
requirements set forth in 40 CFR part 86, subpart S.
    (b) [Reserved]

Subpart P--[Amended]

0
3. Section 85.1511 is revised to read as follows:

Sec.  85.1511  Exemptions and exclusions.

    (a) Individuals, as well as certificate holders, shall be eligible 
for importing vehicles into the United States under the provisions of 
this section, unless otherwise specified.
    (b) Notwithstanding any other requirements of this subpart, a motor 
vehicle or motor vehicle engine entitled to a temporary exemption under 
this paragraph (b) may be conditionally admitted into the United States 
if prior written approval for such conditional admission is obtained 
from the Administrator. Conditional admission shall be under bond. A 
written request for approval from the Administrator shall contain the 
identification required in Sec.  85.1504(a)(1) (except for Sec.  
85.1504(a)(1)(v)) and information that indicates that the importer is 
entitled to the exemption. Noncompliance with provisions of this 
section may result in the forfeiture of the total amount of the bond or 
exportation of the vehicle or engine. The following temporary 
exemptions apply:
    (1) Exemption for repairs or alterations. Vehicles and engines may 
qualify for a temporary exemption under the provisions of 40 CFR 
1068.325(a). Such vehicles or engines may not be registered or licensed 
in the United States for use on public roads and highways.
    (2) Testing exemption. Vehicles and engines may qualify for a 
temporary exemption under the provisions of 40 CFR 1068.325(b). Test 
vehicles or engines may be operated on and registered for use on public 
roads or highways provided that the operation is an integral part of 
the test.
    (3) Precertification exemption. Prototype vehicles for use in 
applying to EPA for certification may be imported by independent 
commercial importers subject to applicable provisions of Sec.  85.1706 
and the following requirements:
    (i) No more than one prototype vehicle for each engine family for 
which an independent commercial importer is seeking certification shall 
be imported by each independent commercial importer.
    (ii) Unless a certificate of conformity is issued for the prototype 
vehicle, the total amount of the bond shall be forfeited or the vehicle 
must be exported within 180 days from the date of entry.
    (4) Display exemptions. Vehicles and engines may qualify for a 
temporary exemption under the provisions of 40 CFR 1068.325(c). Display 
vehicles or engines may not be registered or licensed for use or 
operated on public roads or highways in the United States, unless an 
applicable certificate of conformity has been received.
    (c) Notwithstanding any other requirements of this subpart, a motor 
vehicle or motor vehicle engine may be finally admitted into the United 
States under this paragraph (c) if prior written approval for such 
final admission is obtained from the Administrator. Conditional 
admission of these vehicles is not permitted for the purpose of 
obtaining written approval from the Administrator. A request for 
approval shall contain the identification information required in Sec.  
85.1504(a)(1) (except for Sec.  85.1504(a)(1)(v)) and information that 
indicates that the importer is entitled to the exemption or exclusion. 
The following exemptions or exclusions apply:
    (1) National security exemption. Vehicles may be imported under the 
national security exemption found at 40 CFR 1068.315(a). Only persons 
who are manufacturers may import a vehicle under a national security 
exemption.
    (2) Hardship exemption. The Administrator may exempt on a case-by-
case basis certain motor vehicles from Federal emission requirements to 
accommodate unforeseen cases of extreme hardship or extraordinary

[[Page 57374]]

circumstances. Some examples are as follows:
    (i) Handicapped individuals who need a special vehicle unavailable 
in a certified configuration;
    (ii) Individuals who purchase a vehicle in a foreign country where 
resale is prohibited upon the departure of such an individual;
    (iii) Individuals emigrating from a foreign country to the U.S. in 
circumstances of severe hardship.
    (d) Foreign diplomatic and military personnel may import 
nonconforming vehicles without bond. At the time of admission, the 
importer shall submit to the Administrator the written report required 
in Sec.  85.1504(a)(1) (except for information required by Sec.  
85.1504(a)(1)(v)). Such vehicles may not be sold in the United States.
    (e) Racing vehicles may be imported by any person provided the 
vehicles meet one or more of the exclusion criteria specified in Sec.  
85.1703. Racing vehicles may not be registered or licensed for use on 
or operated on public roads and highways in the United States.
    (f) The following exclusions and exemptions apply based on date of 
original manufacture:
    (1) Notwithstanding any other requirements of this subpart, the 
following motor vehicles or motor vehicle engines are excluded from the 
requirements of the Act in accordance with section 216(3) of the Act 
and may be imported by any person:
    (i) Gasoline-fueled light-duty vehicles and light-duty trucks 
originally manufactured prior to January 1, 1968.
    (ii) Diesel-fueled light-duty vehicles originally manufactured 
prior to January 1, 1975.
    (iii) Diesel-fueled light-duty trucks originally manufactured prior 
to January 1, 1976.
    (iv) Motorcycles originally manufactured prior to January 1, 1978.
    (v) Gasoline-fueled and diesel-fueled heavy-duty engines originally 
manufactured prior to January 1, 1970.
    (2) Notwithstanding any other requirements of this subpart, a motor 
vehicle or motor vehicle engine not subject to an exclusion under 
paragraph (f)(1) of this section but greater than twenty OP years old 
is entitled to an exemption from the requirements of the Act, provided 
that it is imported into the United States by a certificate holder. At 
the time of admission, the certificate holder shall submit to the 
Administrator the written report required in Sec.  85.1504(a)(1) 
(except for information required by Sec.  85.1504(a)(1)(v)).
    (g) Applications for exemptions and exclusions provided for in 
paragraphs (b) and (c) of this section shall be mailed to the 
Designated Compliance Officer (see 40 CFR 1068.30).
    (h) Vehicles conditionally or finally admitted under this section 
must still comply with all applicable requirements, if any, of the 
Energy Tax Act of 1978, the Energy Policy and Conservation Act and any 
other Federal or state requirements.

Subpart R--[Amended]

0
4. Section 85.1701 is revised to read as follows:

Sec.  85.1701  General applicability.

    (a) The provisions of this subpart regarding exemptions are 
applicable to new and in-use motor vehicles and motor vehicle engines, 
except as follows:
    (1) Beginning January 1, 2014, the exemption provisions of 40 CFR 
part 1068, subpart C, apply for heavy-duty motor vehicles and engines, 
except that the competition exemption of 40 CFR 1068.235 and the 
hardship exemption provisions of 40 CFR 1068.245, 1068.250, and 
1068.255 do not apply for motor vehicle engines.
    (2) Prior to January 1, 2014, the provisions of Sec. Sec.  85.1706 
through 85.1709 apply for heavy-duty motor vehicle engines.
    (b) The provisions of this subpart regarding exclusion are 
applicable after the effective date of these regulations.
    (c) References in this subpart to engine families and emission 
control systems shall be deemed to apply to durability groups and test 
groups as applicable for manufacturers certifying new light-duty 
vehicles, light-duty trucks, and Otto-cycle complete heavy-duty 
vehicles under the provisions of 40 CFR part 86, subpart S.
    (d) In a given model year, manufacturers of motor vehicles and 
motor vehicle engines may ask us to approve the use of administrative 
or compliance procedures specified in 40 CFR part 1068 instead of the 
comparable procedures that apply for vehicles or engines certified 
under this part or 40 CFR part 86.

Subpart T--[Amended]

0
5. Section 85.1901 is revised to read as follows:

Sec.  85.1901  Applicability.

    Except as specified in this section, the requirements of this 
subpart shall be applicable to all 1972 and later model year vehicles 
and engines. The requirement to report emission-related defects 
affecting a given class or category of vehicles or engines shall remain 
applicable for five years from the end of the model year in which such 
vehicles or engines were manufactured. Manufacturers of heavy-duty 
motor vehicle engines may comply with the defect reporting requirements 
of 40 CFR 1068.501 instead of the requirements of this subpart.

PART 86--CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES 
AND ENGINES

0
6. The authority citation for part 86 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

0
7. Section 86.1 is amended by adding paragraphs (b)(2)(xli) and 
(b)(2)(xlii) and removing and reserving paragraph (b)(4)(i)(A) to read 
as follows:

Sec.  86.1  Reference materials.

* * * * *
    (b) * * *
    (2) * * *
    (xli) SAE J1711, Recommended Practice for Measuring the Exhaust 
Emissions and Fuel Economy of Hybrid-Electric Vehicles, Including Plug-
In Hybrid Vehicles, June 2010, IBR approved for Sec.  86.1811-04(n).
    (xlii) SAE J1634, Electric Vehicle Energy Consumption and Range 
Test Procedure, Cancelled October 2002, IBR approved for Sec.  86.1811-
04(n).
* * * * *
    (4) * * *
    (i) * * *
    (A) [Reserved]
* * * * *

Subpart A--[Amended]

0
8. Section 86.010-18 is amended by adding paragraphs (j)(1)(ii)(E) and 
(q) to read as follows:

Sec.  86.010-18  On-board Diagnostics for engines used in applications 
greater than 14,000 pounds GVWR.

* * * * *
    (j) * * *
    (1) * * *
    (ii) * * *
    (E) For hybrid engine families with projected U.S.-directed 
production volume of less than 5,000 engines, the manufacturers are 
only required to test one engine-hybrid combination per family.
* * * * *
    (q) Optional phase-in for hybrid vehicles. This paragraph (q) 
applies for model year 2013 through 2015 engines when used with hybrid 
powertrain systems. It also applies for model year 2016 engines used 
with hybrid powertrain systems that were offered for

[[Page 57375]]

sale prior to January 1, 2013, as specified in paragraph (q)(4) of this 
section. Manufacturers choosing to use the provisions of this paragraph 
(q) must submit an annual pre-compliance report to EPA for model years 
2013 and later, as specified in paragraph (q)(5) of this section. Note 
that all hybrid powertrain systems must be fully compliant with the OBD 
requirements of this section no later than model year 2017.
    (1) If an engine-hybrid system has been certified by the California 
Air Resources Board with respect to its OBD requirements and it 
effectively meets the full OBD requirements of this section, all 
equivalent systems must meet those same requirements and may not be 
certified under this paragraph (q). For purposes of this paragraph 
(q)(1), an engine-hybrid system is considered to be equivalent to the 
certified system if it uses the same basic design (e.g. displacement) 
for the engine and primary hybrid components (see paragraph (q)(4) of 
this section). Equivalent systems may have minor hardware or 
calibration differences.
    (2) As of 2013, if an engine-hybrid system has not been certified 
to meet the full OBD requirements of this section, it must comply with 
the following requirements:
    (i) The engine in its installed configuration must meet the EMD and 
EMD+ requirements in 13 CCR Sec.  1971.1(d)(7.1.4) of the California 
Code of Regulations. For purposes of this paragraph (q), a given EMD 
requirement is deemed to be met if the engine's OBD system addresses 
the same function. This allowance does not apply for OBD monitors or 
diagnostics that have been modified under paragraph (q)(2)(ii) of this 
section.
    (ii) The engine-hybrid system must maintain existing OBD capability 
for engines where the same or equivalent engine has been OBD certified. 
An equivalent engine is one produced by the same engine manufacturer 
with the same fundamental design, but that may have hardware or 
calibration differences that do not impact OBD functionality, such as 
slightly different displacement, rated power, or fuel system. (Note 
that engines with the same fundamental design will be presumed to be 
equivalent unless the manufacturer demonstrates that the differences 
effectively preclude applying equivalent OBD systems.) Though the OBD 
capability must be maintained, it does not have to meet detection 
thresholds (as described in Tables 1 and 2 of this section) and in-use 
performance frequency requirements (as described in paragraph (d) of 
this section). A manufacturer may modify detection thresholds to 
prevent false detection, and must indicate all deviations from the 
originally certified package with engineering justification in the 
certification documentation.
    (iii) This paragraph (q)(2)(iii) applies for derivatives of hybrid 
powertrain system designs that were offered for sale prior to January 
1, 2013. Until these systems achieve full OBD certification, they must 
at a minimum maintain all fault-detection and diagnostic capability 
included on similar systems offered for sale prior to 2013. 
Manufacturers choosing to use the provisions of this paragraph (q)(2) 
must keep copies of the service manuals (and similar documents) for 
these previous model years to show the technical description of the 
system's fault detection and diagnostic capabilities.
    (iv) You must submit an annual pre-compliance report to EPA for 
model years 2013 and later, as specified in paragraph (q)(5) of this 
section.
    (3) Engine-hybrid systems may be certified to the requirements of 
paragraph (q)(2) of this section by the engine manufacturer, the hybrid 
system manufacturer, or the vehicle manufacturer. If engine 
manufacturers certify the engine hybrid system, they must provide 
detailed installation instructions. Where the engine manufacturer does 
not specifically certify its engines for use in hybrid vehicles under 
this paragraph (q), the hybrid system manufacturer and vehicle 
manufacturer must install the engine to conform to the requirements of 
this section (i.e., full OBD) or recertify under paragraph (q)(2) of 
this section.
    (4) The provisions of this paragraph (q) apply for model year 2016 
engines where you demonstrate that the hybrid powertrain system used is 
a derivative of a design that was offered for sale prior to January 1, 
2013. In this case, you may ask us to consider the original system and 
the later system to be the same model for purposes of this paragraph 
(q), unless the systems are fundamentally different. In determining 
whether such systems are derivative or fundamentally different, we will 
consider factors such as the similarity of the following:
    (i) Transmissions.
    (ii) Hybrid machines (where ``hybrid machine'' means any system 
that is the part of a hybrid vehicle system that captures energy from 
and returns energy to the powertrain).
    (iii) Hybrid architecture (such as parallel or series).
    (iv) Motor/generator size, controller/CPU (memory or inputs/
outputs), control algorithm, and batteries. This paragraph (q)(4)(iv) 
applies only if all of these are modified simultaneously.
    (5) Manufacturers choosing to use the provisions of this paragraph 
(q) must submit an annual pre-compliance report to EPA for model years 
2013 and later. Engine manufacturers must submit this report with their 
engine certification information. Hybrid manufacturers that are not 
certifying the engine-hybrid system must submit their report by June 1 
of the model year, or at the time of certification if they choose to 
certify. Include the following in the report:
    (i) A description of the manufacturer's product plans and of the 
engine-hybrid systems being certified.
    (ii) A description of activities undertaken and progress made by 
the manufacturer towards achieving full OBD certification, including 
monitoring, diagnostics, and standardization.
    (iii) For model year 2016 engines, a description of your basis for 
applying the provision of this paragraph (q) to the engines.

0
9. A new Sec.  86.012-2 is added to subpart A to read as follows:

Sec.  86.012-2  Definitions.

    The definitions of Sec.  86.010-2 continue to apply to model year 
2010 and later model year vehicles. The definitions listed in this 
section apply beginning with model year 2012. Urban bus means a 
passenger-carrying vehicle with a load capacity of fifteen or more 
passengers and intended primarily for intracity operation, i.e., within 
the confines of a city or greater metropolitan area. Urban bus 
operation is characterized by short rides and frequent stops. To 
facilitate this type of operation, more than one set of quick-operating 
entrance and exit doors would normally be installed. Since fares are 
usually paid in cash or tokens, rather than purchased in advance in the 
form of tickets, urban buses would normally have equipment installed 
for collection of fares. Urban buses are also typically characterized 
by the absence of equipment and facilities for long distance travel, 
e.g., rest rooms, large luggage compartments, and facilities for 
stowing carry-on luggage.

0
10. A new Sec.  86.016-1 is added to subpart A to read as follows:

Sec.  86.016-1  General applicability.

    (a) Applicability. The provisions of this subpart generally apply 
to 2005 and later model year new Otto-cycle heavy-duty engines used in 
incomplete vehicles and vehicles above 14,000 pounds GVWR and 2005 and 
later model year new diesel-cycle heavy-duty engines. In cases where a 
provision

[[Page 57376]]

applies only to a certain vehicle group based on its model year, 
vehicle class, motor fuel, engine type, or other distinguishing 
characteristics, the limited applicability is cited in the appropriate 
section or paragraph. The provisions of this subpart continue to 
generally apply to 2000 and earlier model year new Otto-cycle and 
diesel-cycle light-duty vehicles, 2000 and earlier model year new Otto-
cycle and diesel-cycle light-duty trucks, and 2004 and earlier model 
year new Otto-cycle complete heavy-duty vehicles at or below 14,000 
pounds GVWR. Provisions generally applicable to 2001 and later model 
year new Otto-cycle and diesel-cycle light-duty vehicles, 2001 and 
later model year new Otto-cycle and diesel-cycle light-duty trucks, and 
2005 and later model year Otto-cycle complete heavy-duty vehicles at or 
below 14,000 pounds GVWR are located in subpart S of this part.
    (b) Optional applicability. A manufacturer may request to certify 
any incomplete Otto-cycle heavy-duty vehicle of 14,000 pounds Gross 
Vehicle Weight Rating or less in accordance with the provisions for 
Otto-cycle complete heavy-duty vehicles located in subpart S of this 
part. Heavy-duty engine or heavy-duty vehicle provisions of this 
subpart A do not apply to such a vehicle.
    (c) Otto-cycle heavy-duty engines and vehicles. The following 
requirements apply to Otto-cycle heavy-duty engines and vehicles:
    (1) Exhaust emission standards according to the provisions of Sec.  
86.008-10 or Sec.  86.1816, as applicable.
    (2) On-board diagnostics requirements according to the provisions 
of Sec.  86.007-17 or Sec.  86.1806, as applicable.
    (3) Evaporative emission standards as follows:
    (i) Evaporative emission standards for complete vehicles according 
to the provisions of Sec. Sec.  86.1810 and 86.1816.
    (ii) For 2013 and earlier model years, evaporative emission 
standards for incomplete vehicles according to the provisions of Sec.  
86.008-10, or Sec. Sec.  86.1810 and 86.1816, as applicable.
    (iii) For 2014 and later model years, evaporative emission 
standards for incomplete vehicles according to the provisions of 
Sec. Sec.  86.1810 and 86.1816, or 40 CFR part 1037, as applicable.
    (4) Refueling emission requirements for Otto-cycle complete 
vehicles according to the provisions of Sec. Sec.  86.1810 and 86.1816.
    (d) Non-petroleum fueled vehicles. The standards and requirements 
of this part apply to model year 2016 and later non-petroleum fueled 
motor vehicles as follows:
    (1) The standards and requirements of this part apply as specified 
for vehicles fueled with methanol, natural gas, and LPG.
    (2) The standards and requirements of subpart S of this part apply 
as specified for light-duty vehicles and light-duty trucks.
    (3) The standards and requirements of this part applicable to 
methanol-fueled heavy-duty vehicles and engines (including flexible 
fuel vehicles and engines) apply to heavy-duty vehicles and engines 
fueled with any oxygenated fuel (including flexible fuel vehicles and 
engines). Most significantly, this means that the hydrocarbon standards 
apply as NMHCE and the vehicles and engines must be tested using the 
applicable oxygenated fuel according to the test procedures in 40 CFR 
part 1065 applicable for oxygenated fuels. For purposes of this 
paragraph (d), oxygenated fuel means any fuel containing at least 50 
volume percent oxygenated compounds. For example, a fuel mixture of 85 
gallons of ethanol and 15 gallons of gasoline is an oxygenated fuel, 
while a fuel mixture of 15 gallons of ethanol and 85 gallons of 
gasoline is not an oxygenated fuel.
    (4) The standards and requirements of subpart S of this part 
applicable to heavy-duty vehicles under 14,000 pounds GVWR apply to all 
heavy-duty vehicles powered solely by electricity, including plug-in 
electric vehicles and solar-powered vehicles. Use good engineering 
judgment to apply these requirements to these vehicles, including 
applying these provisions to vehicles over 14,000 pounds GVWR. Electric 
heavy-duty vehicles may not generate NOX or PM emission 
credits. Heavy-duty vehicles powered solely by electricity are deemed 
to have zero emissions of regulated pollutants.
    (5) The standards and requirements of this part applicable to 
diesel-fueled heavy-duty vehicles and engines apply to all other heavy-
duty vehicles and engines not otherwise addressed in this paragraph 
(d).
    (6) See 40 CFR parts 1036 and 1037 for requirements related to 
greenhouse gas emissions.
    (7) Manufacturers may voluntarily certify to the standards of 
paragraphs (d)(3) through (5) of this section before model year 2016. 
Note that other provisions in this part require compliance with the 
standards described in paragraphs (d)(1) and (2) of this section for 
model years before 2016.
    (e) Small volume manufacturers. Special certification procedures 
are available for any manufacturer whose projected combined U.S. sales 
of light-duty vehicles, light-duty trucks, heavy-duty vehicles, and 
heavy-duty engines in its product line (including all vehicles and 
engines imported under the provisions of 40 CFR 85.1505 and 85.1509) 
are fewer than 10,000 units for the model year in which the 
manufacturer seeks certification. To certify its product line under 
these optional procedures, the small-volume manufacturer must first 
obtain the Administrator's approval. The manufacturer must meet the 
eligibility criteria specified in Sec.  86.098-14(b) before the 
Administrator's approval will be granted. The small-volume 
manufacturer's certification procedures are described in Sec.  86.098-
14.
    (f) Optional procedures for determining exhaust opacity. (1) The 
provisions of subpart I of this part apply to tests which are performed 
by the Administrator, and optionally, by the manufacturer.
    (2) Measurement procedures, other than those described in subpart I 
of this part, may be used by the manufacturer provided the manufacturer 
satisfies the requirements of Sec.  86.007-23(f).
    (3) When a manufacturer chooses to use an alternative measurement 
procedure, it has the responsibility to determine whether the results 
obtained by the procedure will correlate with the results which would 
be obtained from the measurement procedure in subpart I of this part. 
Consequently, the Administrator will not routinely approve or 
disapprove any alternative opacity measurement procedure or any 
associated correlation data which the manufacturer elects to use to 
satisfy the data requirements for subpart I of this part.
    (4) If a confirmatory test is performed and the results indicate 
there is a systematic problem suggesting that the data generated under 
an optional alternative measurement procedure do not adequately 
correlate with data obtained in accordance with the procedures 
described in subpart I of this part, EPA may require that all 
certificates of conformity not already issued be based on data obtained 
from procedures described in subpart I of this part.

0
11. Section 86.090-2 is amended by revising the definition of ``primary 
intended service class'' to read as follows:

Sec.  86.090-2  Definitions.

* * * * *
    Primary intended service class has the meaning given in 40 CFR 
1036.140.
* * * * *

[[Page 57377]]

Subpart B--[Amended]

0
12. Section 86.144-94 is amended by adding paragraphs (b)(11) and 
(c)(10) to read as follows:

Sec.  86.144-94  Calculations; exhaust emissions.

* * * * *
    (b) * * *
    (11) Nitrous Oxide Mass: Vmix x DensityN2O x 
(N2Oconc/1,000,000)
    (c) * * *
    (10)(i) N2Omass = Nitrous oxide emissions, in 
grams per test phase.
    (ii) DensityN2O = Density of nitrous oxide is 51.81 g/
ft\3\ (1.83 kg/m\3\), at 68 [deg]F (20 [deg]C) and 760 mm Hg (101.3kPa) 
pressure.
    (iii)(A) N2Oconc = Nitrous oxide 
concentration of the dilute exhaust sample corrected for background, in 
ppm.
    (B) N2Oconc = N2Oe - 
N2Od(1 - (1/DF)).

Where:

N2Oe = Nitrous oxide concentration of the 
dilute exhaust sample as measured, in ppm.
N2Od = Nitrous oxide concentration of the 
dilution air as measured, in ppm.
* * * * *

Subpart F--[Amended]

0
13. Section 86.544-90 is amended by adding paragraphs (b)(8) and (c)(8) 
to read as follows:

Sec.  86.544-90  Calculations; exhaust emissions.

* * * * *
    (b) * * *
    (8) Nitrous Oxide Mass: Vmix x DensityN2O x 
(N2Oconc/1,000,000)
    (c) * * *
    (8)(i) N2Omass = Nitrous oxide emissions, in 
grams per test phase.
    (ii) Density N2O = Density of nitrous oxide is 51.81 g/ft\3\ (1.83 
kg/m\3\), at 68 [deg]F (20 [deg]C) and 760 mm Hg (101.3kPa) pressure.
    (iii)(A) N2Oconc = Nitrous oxide 
concentration of the dilute exhaust sample corrected for background, in 
ppm.
    (B) N2Oconc = N2Oe-
N2Od(1-(1/DF)).

Where:

N2Oe = Nitrous oxide concentration of the 
dilute exhaust sample as measured, in ppm.
N2Od = Nitrous oxide concentration of the 
dilution air as measured, in ppm.
* * * * *

Subpart N--[Amended]

0
14. Section 86.1305-2010 is amended by revising paragraph (b) to read 
as follows:

Sec.  86.1305-2010  Introduction; structure of subpart.

* * * * *
    (b) Use the applicable equipment and procedures for spark-ignition 
or compression-ignition engines in 40 CFR part 1065 to determine 
whether engines meet the duty-cycle emission standards in subpart A of 
this part. Measure the emissions of all regulated pollutants as 
specified in 40 CFR part 1065. Use the duty cycles and procedures 
specified in Sec. Sec.  86.1333-2010, 86.1360-2007, and 86.1362-2010. 
Adjust emission results from engines using aftertreatment technology 
with infrequent regeneration events as described in Sec.  86.004-28.
* * * * *

Subpart S--[Amended]

Sec.  86.1806-01--[Amended]  

0
15. Section 86.1806-01 is amended by removing and reserving paragraph 
(b)(8)(ii).

Sec.  86.1806-05--[Amended]  

0
16. Section 86.1806-05 is amended by removing and reserving paragraph 
(b)(8)(ii).

0
17. Section 86.1811-04 is amended by revising paragraph (n) to read as 
follows:

Sec.  86.1811-04  Emission standards for light-duty vehicles, light-
duty trucks and medium-duty passenger vehicles.

* * * * *
    (n) Hybrid electric vehicle (HEV) and Zero Emission Vehicle (ZEV) 
requirements. For FTP and SFTP exhaust emissions, manufacturers must 
measure emissions from all HEVs and ZEVs according to the procedures 
specified in SAE J1711 and SAE J1634, respectively (incorporated by 
reference in Sec.  86.1).
* * * * *

0
18. Section 86.1818-12 is amended by revising paragraph (f) to read as 
follows:

Sec.  86.1818-12  Greenhouse gas emission standards for light-duty 
vehicles, light-duty trucks, and medium-duty passenger vehicles.

* * * * *
    (f) Nitrous oxide (N2O) and methane (CH4) 
exhaust emission standards for passenger automobiles and light trucks. 
Each manufacturer's fleet of combined passenger automobile and light 
trucks must comply with N2O and CH4 standards 
using either the provisions of paragraph (f)(1), (f)(2), or (f)(3) of 
this section. Except with prior EPA approval, a manufacturer may not 
use the provisions of both paragraphs (f)(1) and (2) of this section in 
a model year. For example, a manufacturer may not use the provisions of 
paragraph (f)(1) of this section for their passenger automobile fleet 
and the provisions of paragraph (f)(2) of this section for their light 
truck fleet in the same model year. The manufacturer may use the 
provisions of both paragraphs (f)(1) and (3) of this section in a model 
year. For example, a manufacturer may meet the N2O standard 
in paragraph (f)(1)(i) of this section and an alternative 
CH4 standard determined under paragraph (f)(3) of this 
section in the same model year. Use of the provisions in paragraph 
(f)(3) of this section is limited to the 2012 through 2016 model years.
    (1) Standards applicable to each test group. (i) Exhaust emissions 
of nitrous oxide (N2O) shall not exceed 0.010 grams per mile 
at full useful life, as measured according to the Federal Test 
Procedure (FTP) described in subpart B of this part. Manufacturers may 
optionally determine an alternative N2O standard under 
paragraph (f)(3) of this section. (ii) Exhaust emissions of methane 
(CH4) shall not exceed 0.030 grams per mile at full useful 
life, as measured according to the Federal Test Procedure (FTP) 
described in subpart B of this part. Manufacturers may optionally 
determine an alternative CH4 standard under paragraph (f)(3) 
of this section.
    (2) Include N 2O and CH4 in fleet averaging 
program. Manufacturers may elect to not meet the emission standards in 
paragraph (f)(1) of this section. Manufacturers making this election 
shall include N2O and CH4 emissions in the 
determination of their fleet average carbon-related exhaust emissions, 
as calculated in 40 CFR part 600, subpart F. Manufacturers using this 
option must include both N2O and CH4 full useful 
life values in the fleet average calculations for passenger automobiles 
and light trucks. Use of this option will account for N2O 
and CH4 emissions within the carbon-related exhaust emission 
value determined for each model type according to the provisions of 40 
CFR part 600. This option requires the determination of full useful 
life emission values for both the Federal Test Procedure and the 
Highway Fuel Economy Test. Manufacturers selecting this option are not 
required to demonstrate compliance with the standards in paragraph 
(f)(1) of this section.
    (3) Optional use of alternative N2O and/or 
CH4 standards. Manufacturers may select an alternative 
standard applicable to a test group, for either N2O, 
CH4, or both. For example, a manufacturer may choose to meet 
the N2O standard in paragraph (f)(1)(i) of this section and 
an alternative CH4

[[Page 57378]]

standard in lieu of the standard in paragraph (f)(1)(ii) of this 
section. The alternative standard for each pollutant must be greater 
than the applicable exhaust emission standard specified in paragraph 
(f)(1) of this section. Alternative N2O and CH4 
standards apply to emissions measured according to the Federal Test 
Procedure (FTP) described in Subpart B of this part for the full useful 
life, and become the applicable certification and in-use emission 
standard(s) for the test group. Manufacturers using an alternative 
standard for N2O and/or CH4 must calculate 
emission debits according to the provisions of paragraph (f)(4) of this 
section for each test group/alternative standard combination. Debits 
must be included in the calculation of total credits or debits 
generated in a model year as required under Sec.  86.1865-12(k)(5). For 
flexible fuel vehicles (or other vehicles certified for multiple fuels) 
you must meet these alternative standards when tested on any applicable 
test fuel type.
    (4) CO2-equivalent debits. CO2-equivalent 
debits for test groups using an alternative N2Oand/or 
CH4 standard as determined under paragraph (f)(3) of this 
section shall be calculated according to the following equation and 
rounded to the nearest megagram:
    Debits = [GWP x (Production) x (AltStd--Std) x VLM]/1,000,000

Where:

Debits = N2O or CH4 CO2-equivalent 
debits for a test group using an alternative N2O or 
CH4 standard;
GWP = 25 if calculating CH4 debits and 298 if calculating 
N2O debits;
Production = The number of vehicles of that test group domestically 
produced plus those imported as defined in Sec.  600.511 of this 
chapter;
AltStd = The alternative standard (N2O or CH4) 
selected by the manufacturer under paragraph (f)(3) of this section;
Std = The exhaust emission standard for N2O or 
CH4 specified in paragraph (f)(1) of this section; and
VLM = 195,264 for passenger automobiles and 225,865 for light 
trucks.

0
19. Section 86.1823-08 is amended by revising paragraph (m) to read as 
follows:

Sec.  86.1823-08  Durability demonstration procedures for exhaust 
emissions.

* * * * *
    (m) Durability demonstration procedures for vehicles subject to the 
greenhouse gas exhaust emission standards specified in Sec.  86.1818. 
(1) CO2. (i) Unless otherwise specified under paragraph 
(m)(1)(ii) of this section, manufacturers may use a multiplicative 
CO2 deterioration factor of one or an additive deterioration 
factor of zero to determine full useful life emissions for the FTP and 
HFET tests.
    (ii) Based on an analysis of industry-wide data, EPA may 
periodically establish and/or update the deterioration factor for 
CO2 emissions, including air conditioning and other credit-
related emissions. Deterioration factors established and/or updated 
under this paragraph (m)(1)(ii) will provide adequate lead time for 
manufacturers to plan for the change.
    (iii) Alternatively, manufacturers may use the whole-vehicle 
mileage accumulation procedures in Sec.  86.1823-08 (c) or (d)(1) to 
determine CO2 deterioration factors. In this case, each FTP 
test performed on the durability data vehicle selected under Sec.  
86.1822 must also be accompanied by an HFET test, and combined FTP/HFET 
CO2 results determined by averaging the city (FTP) and 
highway (HFET) CO2 values, weighted 0.55 and 0.45 
respectively. The deterioration factor will be determined for this 
combined CO2 value. Calculated multiplicative deterioration 
factors that are less than one shall be set to equal one, and 
calculated additive deterioration factors that are less than zero shall 
be set to zero.
    (iv) If, in the good engineering judgment of the manufacturer, the 
deterioration factors determined according to paragraphs (m)(1)(i), 
(m)(1)(ii), or (m)(1)(iii) of this section do not adequately account 
for the expected CO2 emission deterioration over the 
vehicle's useful life, the manufacturer may petition EPA to request a 
more appropriate deterioration factor.
    (2) N2O and CH4. (i) For manufacturers 
complying with the FTP emission standards for N2O and 
CH4 specified in Sec.  86.1818-12(f)(1) or determined under 
Sec.  86.1818-12(f)(3), FTP-based deterioration factors for 
N2O and CH4 shall be determined according to the 
provisions of paragraphs (a) through (l) of this section.
    (ii) For manufacturers complying with the fleet averaging option 
for N2O and CH4 as allowed under Sec.  86.1818-
12(f)(2), deterioration factors based on FTP testing shall be 
determined and may be used to determine full useful life emissions for 
the FTP and HFET tests. The manufacturer may at its option determine 
separate deterioration factors for the FTP and HFET test cycles, in 
which case each FTP test performed on the durability data vehicle 
selected under Sec.  86.1822 of this part must also be accompanied by 
an HFET test.
    (iii) For the 2012 through 2014 model years only, manufacturers may 
use alternative deterioration factors. For N2O, the 
alternative deterioration factor to be used to adjust FTP and HFET 
emissions is the deterioration factor determined for NOX 
emissions according to the provisions of this section. For 
CH4, the alternative deterioration factor to be used to 
adjust FTP and HFET emissions is the deterioration factor determined 
for NMOG or NMHC emissions according to the provisions of this section.
    (3) Other carbon-related exhaust emissions. FTP-based deterioration 
factors shall be determined for carbon-related exhaust emissions 
(CREE), hydrocarbons, and CO according to the provisions of paragraphs 
(a) through (l) of this section. The FTP-based deterioration factor 
shall be used to determine full useful life emissions for both the FTP 
(city) and HFET (highway) test cycles. The manufacturer may at its 
option determine separate deterioration factors for the FTP and HFET 
test cycles, in which case each FTP test performed on the durability 
data vehicle selected under Sec.  86.1822 must also be accompanied by 
an HFET test. In lieu of determining emission-specific deterioration 
factors for the specific hydrocarbons of CH3OH (methanol), 
HCHO (formaldehyde), C2H5OH (ethanol), and 
C2H4O (acetaldehyde) as may be required for some 
alternative fuel vehicles, manufacturers may use the additive or 
multiplicative deterioration factor determined for (or derived from, 
using good engineering judgment) NMOG or NMHC emissions according to 
the provisions of this section.
    (4) Air Conditioning leakage and efficiency or other emission 
credit requirements to comply with exhaust CO2 standards. 
Manufactures will attest to the durability of components and systems 
used to meet the CO2 standards. Manufacturers may submit 
engineering data to provide durability demonstration. Deterioration 
factors do not apply to emission-related components and systems used to 
generate air conditioning leakage and/or efficiency credits.

0
20. Section 86.1844-01 is amended by revising paragraph (d)(15) to read 
as follows:

Sec.  86.1844-01  Information requirements: Application for 
certification and submittal of information upon request.

* * * * *
    (d) * * *
    (15)(i) For HEVs and EVs, describe the recharging procedures and 
methods for determining battery performance, such as state of charge 
and charging capacity.
    (ii) For vehicles with fuel-fired heaters, include the information 
specified in this paragraph (d)(15)(ii).

[[Page 57379]]

Describe the control system logic of the fuel-fired heater, including 
an evaluation of the conditions under which it can be operated and an 
evaluation of the possible operational modes and conditions under which 
evaporative emissions can exist. Use good engineering judgment to 
establish an estimated exhaust emission rate from the fuel-fired heater 
in grams per mile. Describe the testing used to establish the exhaust 
emission rate.
* * * * *

0
21. Section 86.1863-07 is revised to read as follows:

Sec.  86.1863-07  Chassis certification for diesel vehicles.

    (a) A manufacturer may optionally certify heavy-duty diesel 
vehicles 14,000 pounds GVWR or less to the standards specified in Sec.  
86.1816. Such vehicles must meet all the requirements of this subpart S 
that are applicable to Otto-cycle vehicles, except for evaporative, 
refueling, and OBD requirements where the diesel-specific OBD 
requirements would apply.
    (b) For OBD, diesel vehicles optionally certified under this 
section are subject to the OBD requirements of Sec.  86.1806.
    (c) Diesel vehicles certified under this section may be tested 
using the test fuels, sampling systems, or analytical systems specified 
for diesel engines in subpart N of this part or in 40 CFR part 1065.
    (d) Diesel vehicles optionally certified under this section to the 
standards of this subpart may not be included in any averaging, 
banking, or trading program for criteria emissions under this part.
    (e) The provisions of Sec.  86.004-40 apply to the engines in 
vehicles certified under this section.
    (f) Diesel vehicles may be certified under this section to the 
standards applicable to model year 2008 in earlier model years.
    (g) Diesel vehicles optionally certified under this section in 
model years 2007, 2008, or 2009 shall be included in phase-in 
calculations specified in Sec.  86.007-11(g).
    (h) Diesel vehicles subject to the standards of 40 CFR 1037.104 are 
subject to the provisions of this subpart as specified in 40 CFR 
1037.104.
    (i) Non-petroleum fueled complete vehicles subject to the standards 
and requirements of this part under Sec.  86.016-01(d)(5) are subject 
to the provisions of this section applicable to diesel-fueled heavy-
duty vehicles.

0
22. Section 86.1865-12 is amended by adding paragraph (k)(5)(iv) and by 
revising paragraphs (l)(1)(ii)(F) and (l)(2)(i) to read as follows:

Sec.  86.1865-12  How to comply with the fleet average CO2 
standards.

* * * * *
    (k) * * *
    (5) * * *
    (iv) N2O and/or CH4 CO2-equivalent 
debits accumulated according to the provisions of Sec.  86.1818-
12(f)(4).
* * * * *
    (l) * * *
    (1) * * *
    (ii) * * *
    (F) Carbon-related exhaust emission standard, N2O 
emission standard, and CH4 emission standard to which the 
passenger car or light truck is certified.
* * * * *
    (2) * * *
    (i) Each manufacturer must submit an annual report. The annual 
report must contain for each applicable CO2 standard, the 
calculated fleet average CO2 value, all values required to 
calculate the CO2 emissions value, the number of credits 
generated or debits incurred, all the values required to calculate the 
credits or debits, and the resulting balance of credits or debits. For 
each applicable alternative N2O and/or CH4 
standard selected under the provisions of Sec.  86.1818-12(f)(3), the 
report must contain the N2O and/or CH4 
CO2-equivalent debits calculated according to Sec.  86.1818-
12(f)(4) for each test group and all values required to calculate the 
number of debits incurred.
* * * * *

PART 600--FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF 
MOTOR VEHICLES

0
23. The authority citation for part 600 continues to read as follows:

    Authority: 49 U.S.C. 32901--23919q, Pub. L. 109-58.

Subpart A--[Amended]

0
24. Section 600.011 is amended by revising paragraph (c)(3) to read as 
follows:

Sec.  600.011  Incorporation by reference.

* * * * *
    (c) * * *
    (3) SAE J1711, Recommended Practice for Measuring the Exhaust 
Emissions and Fuel Economy of Hybrid-Electric Vehicles, Including Plug-
In Hybrid Vehicles, June 2010, IBR approved for Sec. Sec.  600.114-
12(c) and (f), 600.116-12(b), and 600.311-12(d), (j), and (k).
* * * * *

Subpart B--[Amended]

0
25. Section 600.114-12 is amended by revising the introductory text of 
paragraph (c), paragraph (e)(2)(ii), and the introductory text of 
paragraph (f), to read as follows:

Sec.  600.114-12  Vehicle-specific 5-cycle fuel economy and carbon-
related exhaust emission calculations.

* * * * *
    (c) Fuel economy calculations for hybrid electric vehicles. Test 
hybrid electric vehicles as described in SAE J1711 (incorporated by 
reference in Sec.  600.011). For FTP testing, this generally involves 
emission sampling over four phases (bags) of the UDDS (cold-start, 
transient, warm-start, transient); however, these four phases may be 
combined into two phases (phases 1 + 2 and phases 3 + 4). Calculations 
for these sampling methods follow:
* * * * *
    (e) * * *
    (2) * * *
    (ii) Determine the 5-cycle highway carbon-related exhaust emissions 
according to the following formula:
[GRAPHIC] [TIFF OMITTED] TR15SE11.064

Where:
[GRAPHIC] [TIFF OMITTED] TR15SE11.065

[[Page 57380]]

Start CREE75 = 3.6 x (Bag 1CREE75 - Bag 
3CREE75)
Running CREE = 1.007 x [(0.79 x US06 Highway CREE) + (0.21 x HFET 
CREE)] + [0.377 x 0.133 x ((0.00540 x A) + (0.1357 x US06 CREE))]
* * * * *
    (f) CO2 and carbon-related exhaust emissions 
calculations for hybrid electric vehicles. Test hybrid electric 
vehicles as described in SAE J1711 (incorporated by reference in Sec.  
600.011). For FTP testing, this generally involves emission sampling 
over four phases (bags) of the UDDS (cold-start, transient, warm-start, 
transient); however, these four phases may be combined into two phases 
(phases 1 + 2 and phases 3 + 4). Calculations for these sampling 
methods follow:
* * * * *
0
26. Section 600.115-11 is amended by revising the introductory text to 
read as follows:

Sec.  600.115-11  Criteria for determining the fuel economy label 
calculation method.

    This section provides the criteria to determine if the derived 5-
cycle method for determining fuel economy label values, as specified in 
Sec.  600.210-08(a)(2) or (b)(2) or Sec.  600.210-12(a)(2) or (b)(2), 
as applicable, may be used to determine label values. Separate criteria 
apply to city and highway fuel economy for each test group. The 
provisions of this section are optional. If this option is not chosen, 
or if the criteria provided in this section are not met, fuel economy 
label values must be determined according to the vehicle-specific 5-
cycle method specified in Sec.  600.210-08(a)(1) or (b)(1) or Sec.  
600.210-12(a)(1) or (b)(1), as applicable. However, dedicated 
alternative-fuel vehicles, dual fuel vehicles when operating on the 
alternative fuel, plug-in hybrid electric vehicles while operating in 
charge-depleting mode, MDPVs, and vehicles imported by Independent 
Commercial Importers may use the derived 5-cycle method for determining 
fuel economy label values whether or not the criteria provided in this 
section are met. Manufacturers may alternatively account for this 
effect by multiplying 2-cycle fuel economy values by 0.7 and dividing 
2-cycle CO2 emission values by 0.7.
* * * * *

0
27. Section 600.116-12 is amended by adding paragraph (a)(6) and 
revising the equation for UFi in paragraph (b)(4) to read as 
follows:

Sec.  600.116-12  Special procedures related to electric vehicles and 
plug-in hybrid electric vehicles.

    (a) * * *
    (6) All label values related to fuel economy, energy consumption, 
and range must be based on 5-cycle testing or on values adjusted to be 
equivalent to 5-cycle results.
    (b) * * *
    (4) * * *
    [GRAPHIC] [TIFF OMITTED] TR15SE11.066
    
* * * * *

Subpart C--[Amended]

0
28. Section 600.210-12 is amended by revising paragraph (d)(3)(ii) to 
read as follows:

Sec.  600.210-12  Calculation of fuel economy and CO2 
emission values for labeling.

* * * * *
    (d) * * *
    (3) * * *
    (ii) Multiply 2-cycle fuel economy values by 0.7 and divide 2-cycle 
CO2 emission values by 0.7.
* * * * *

Subpart D--[Amended]

0
29. Section 600.302-12 is amended by revising paragraph (e)(4) to read 
as follows:

Sec.  600.302-12  Fuel economy label--general provisions.

    (e) * * *
    (4) Insert a slider bar in the right portion of the field to 
characterize the vehicle's level of emission control for ozone-related 
air pollutants relative to that of all vehicles. Position a box with a 
downward-pointing wedge above the slider bar positioned to show where 
that vehicle's emission rating falls relative to the total range. 
Include the vehicle's emission rating (as described in Sec.  600.311) 
inside the box. Include the number 1 in the border at the left end of 
the slider bar; include the number 10 in the border at the right end of 
the slider bar and add the term ``Best'' below the slider bar, directly 
under the number. EPA will periodically calculate and publish updated 
range values as described in Sec.  600.311. Add color to the slider bar 
such that it is blue at the left end of the range, white at the right 
end of the range, and shaded continuously across the range.
* * * * *
0
30. Section 600.311-12 is amended by revising paragraph (f) to read as 
follows:

Sec.  600.311-12  Determination of values for fuel economy labels.

* * * * *
    (f) Fuel savings. Calculate an estimated five-year cost increment 
relative to an average vehicle by multiplying the annual fuel cost from 
paragraph (e) of this section by 5 and subtracting this value from the 
average five-year fuel cost. We will calculate the average five-year 
fuel cost from the annual fuel cost equation in paragraph (e) of this 
section based on a gasoline-fueled vehicle with a mean fuel economy 
value, consistent with the value dividing the 5 and 6 ratings under 
paragraph (d) of this section. The average five-year fuel cost for 
model year 2012 is $12,600 for a 22-mpg vehicle that drives 15,000 
miles per year with gasoline priced at $3.70 per gallon. We may 
periodically update this five year reference fuel cost for later model 
years to better characterize the fuel economy for an average vehicle. 
Round the calculated five-year cost increment to the nearest $50. 
Negative values represent a cost increase compared to the average 
vehicle.

PART 1033--CONTROL OF EMISSIONS FROM LOCOMOTIVES

0
31. The authority citation for part 1033 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

Subpart G--[Amended]

0
32. Section 1033.625 is amended by revising paragraph (a)(2) to read as 
follows:

Sec.  1033.625  Special certification provisions for non-locomotive-
specific engines.

* * * * *
    (a) * * *
    (2) The engines were certified to PM, NOX, and 
hydrocarbon standards that are numerically lower than the applicable 
locomotive standards of this part.
* * * * *

[[Page 57381]]

0
33. A new part 1036 is added to subchapter U to read as follows:

PART 1036--CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY 
HIGHWAY ENGINES

Subpart A--Overview and Applicability
Sec.
1036.1 Does this part apply for my engines?
1036.2 Who is responsible for compliance?
1036.5 Which engines are excluded from this part's requirements?
1036.10 How is this part organized?
1036.15 Do any other regulation parts apply to me?
1036.30 Submission of information.
Subpart B--Emission Standards and Related Requirements
1036.100 Overview of exhaust emission standards.
1036.108 Greenhouse gas emission standards.
1036.115 Other requirements.
1036.130 Installation instructions for vehicle manufacturers.
1036.135 Labeling.
1036.140 Primary intended service class.
1036.150 Interim provisions.
Subpart C--Certifying Engine Families
1036.205 What must I include in my application?
1036.210 Preliminary approval before certification.
1036.225 Amending my application for certification.
1036.230 Selecting engine families.
1036.235 Testing requirements for certification.
1036.241 Demonstrating compliance with greenhouse gas pollutant 
standards.
1036.250 Reporting and recordkeeping for certification.
1036.255 What decisions may EPA make regarding my certificate of 
conformity?
Subpart D--[Reserved]
Subpart E--In-use Testing
1036.401 In-use testing.
Subpart F--Test Procedures
1036.501 How do I run a valid emission test?
1036.525 Hybrid engines.
1036.530 Calculating greenhouse gas emission rates.
Subpart G--Special Compliance Provisions
1036.601 What compliance provisions apply to these engines?
1036.610 Innovative technology credits and adjustments for reducing 
greenhouse gas emissions.
1036.615 Engines with Rankine cycle waste heat recovery and hybrid 
powertrains.
1036.620 Alternate CO2 standards based on model year 2011 
compression-ignition engines.
1036.625 In-use compliance with family emission limits (FELs).
Subpart H--Averaging, Banking, and Trading for Certification
1036.701 General provisions.
1036.705 Generating and calculating emission credits.
1036.710 Averaging.
1036.715 Banking.
1036.720 Trading.
1036.725 What must I include in my application for certification?
1036.730 ABT reports.
1036.735 Recordkeeping.
1036.740 Restrictions for using emission credits.
1036.745 End-of-year CO2 credit deficits.
1036.750 What can happen if I do not comply with the provisions of 
this subpart?
1036.755 Information provided to the Department of Transportation.
Subpart I--Definitions and Other Reference Information
1036.801 Definitions.
1036.805 Symbols, acronyms, and abbreviations.
1036.810 Incorporation by reference.
1036.815 Confidential information.
1036.820 Requesting a hearing.
1036.825 Reporting and recordkeeping requirements.

    Authority: 42 U.S.C. 7401-7671q.

Subpart A--Overview and Applicability

Sec.  1036.1  Does this part apply for my engines?

    (a) Except as specified in Sec.  1036.5, the provisions of this 
part apply to all new 2014 model year and later heavy-duty engines. 
This includes engines fueled by conventional and alternative fuels.
    (b) This part does not apply with respect to exhaust emission 
standards for HC, CO, NOX, or PM except that the provisions 
of Sec.  1036.601 apply.

Sec.  1036.2  Who is responsible for compliance?

    The regulations in this part 1036 contain provisions that affect 
both engine manufacturers and others. However, the requirements of this 
part are generally addressed to the engine manufacturer. The term 
``you'' generally means the engine manufacturer, especially for issues 
related to certification.

Sec.  1036.5  Which engines are excluded from this part's requirements?

    (a) The provisions of this part do not apply to engines used in 
medium-duty passenger vehicles that are subject to regulation under 40 
CFR part 86, subpart S, except as specified in 40 CFR part 86, subpart 
S, and Sec.  1036.108(a)(4). For example, this exclusion applies for 
engines used in vehicles certified to the standards of 40 CFR 1037.104.
    (b) Engines installed in heavy-duty vehicles that do not provide 
motive power are nonroad engines. The provisions of this part therefore 
do not apply to these engines. See 40 CFR parts 1039, 1048, or 1054 for 
other requirements that apply for these auxiliary engines. See 40 CFR 
part 1037 for requirements that may apply for vehicles using these 
engines, such as the evaporative emission requirements of 40 CFR 
1037.103.
    (c) The provisions of this part do not apply to aircraft or 
aircraft engines. Standards apply separately to certain aircraft 
engines, as described in 40 CFR part 87.
    (d) The provisions of this part do not apply to engines that are 
not internal combustion engines. For example, the provisions of this 
part do not apply to fuel cells.
    (e) The provisions of this part do not apply to engines used in 
heavy-duty vehicles that are subject to light-duty greenhouse gas 
standards under 40 CFR part 86, subpart S, except as specified in 40 
CFR part 86, subpart S, and Sec.  1036.108(a)(4).

Sec.  1036.10  How is this part organized?

    This part 1036 is divided into the following subparts:
    (a) Subpart A of this part defines the applicability of this part 
1036 and gives an overview of regulatory requirements.
    (b) Subpart B of this part describes the emission standards and 
other requirements that must be met to certify engines under this part. 
Note that Sec.  1036.150 describes certain interim requirements and 
compliance provisions that apply only for a limited time.
    (c) Subpart C of this part describes how to apply for a certificate 
of conformity.
    (d) [Reserved]
    (e) Subpart E of this part describes provisions for testing in-use 
engines.
    (f) Subpart F of this part describes how to test your engines 
(including references to other parts of the Code of Federal 
Regulations).
    (g) Subpart G of this part describes requirements, prohibitions, 
and other provisions that apply to engine manufacturers, vehicle 
manufacturers, owners, operators, rebuilders, and all others.
    (h) Subpart H of this part describes how you may generate and use 
emission credits to certify your engines.
    (i) Subpart I of this part contains definitions and other reference 
information.

Sec.  1036.15  Do any other regulation parts apply to me?

    (a) Part 86 of this chapter describes additional requirements that 
apply to

[[Page 57382]]

engines that are subject to this part 1036. This part extensively 
references portions of 40 CFR part 86. For example, the regulations of 
part 86 specify emission standards and certification procedures related 
to criteria pollutants.
    (b) Part 1037 of this chapter describes requirements for 
controlling evaporative emissions and greenhouse gas emissions from 
heavy-duty vehicles, whether or not they use engines certified under 
this part. It also includes standards and requirements that apply 
instead of the standards and requirements of this part in some cases.
    (c) Part 1065 of this chapter describes procedures and equipment 
specifications for testing engines to measure exhaust emissions. 
Subpart F of this part 1036 describes how to apply the provisions of 
part 1065 of this chapter to determine whether engines meet the exhaust 
emission standards in this part.
    (d) Certain provisions of part 1068 of this chapter apply as 
specified in Sec.  1036.601 to everyone, including anyone who 
manufactures, imports, installs, owns, operates, or rebuilds any of the 
engines subject to this part 1036, or vehicles containing these 
engines. Part 1068 of this chapter describes general provisions that 
apply broadly, but do not necessarily apply for all engines or all 
persons. The issues addressed by these provisions include these seven 
areas:
    (1) Prohibited acts and penalties for engine manufacturers, vehicle 
manufacturers, and others.
    (2) Rebuilding and other aftermarket changes.
    (3) Exclusions and exemptions for certain engines.
    (4) Importing engines.
    (5) Selective enforcement audits of your production.
    (6) Recall.
    (7) Procedures for hearings.
    (e) Other parts of this chapter apply if referenced in this part.

Sec.  1036.30  Submission of information.

    Send all reports and requests for approval to the Designated 
Compliance Officer (see Sec.  1036.801). See Sec.  1036.825 for 
additional reporting and recordkeeping provisions.

Subpart B--Emission Standards and Related Requirements

Sec.  1036.100  Overview of exhaust emission standards.

    Engines used in vehicles certified to the applicable chassis 
standards for greenhouse gas pollutants described in 40 CFR 1037.104 
are not subject to the standards specified in this part. All other 
engines subject to this part must meet the greenhouse gas standards in 
Sec.  1036.108 in addition to the criteria pollutant standards of 40 
CFR part 86.

Sec.  1036.108  Greenhouse gas emission standards.

    This section contains standards and other regulations applicable to 
the emission of the air pollutant defined as the aggregate group of six 
greenhouse gases: carbon dioxide, nitrous oxide, methane, 
hydrofluorocarbons, perflurocarbons, and sulfur hexafluoride. This 
section describes the applicable CO2, N2O, and 
CH4 standards for engines. Except as specified in paragraph 
(a)(4) of this section, these standards do not apply for engines used 
in vehicles subject to (or voluntarily certified to) the 
CO2, N2O, and CH4 standards for 
vehicles specified in 40 CFR 1037.104.
    (a) Emission standards. Emission standards apply for engines 
measured using the test procedures specified in subpart F of this part 
as follows:
    (1) CO2 emission standards apply as specified in this 
paragraph (a)(1). The applicable test cycle for measuring 
CO2 emissions differs depending on the engine family's 
primary intended service class and the extent to which the engines will 
be (or were designed to be) used in tractors. For medium and heavy 
heavy-duty engines certified as tractor engines, measure CO2 
emissions using the steady-state duty cycle specified in 40 CFR 86.1362 
(referred to as the SET cycle). This is intended for engines designed 
to be used primarily in tractors and other line-haul applications. Note 
that the use of some SET-certified tractor engines in vocational 
applications does not affect your certification obligation under this 
paragraph (a)(1); see other provisions of this part and 40 CFR part 
1037 for limits on using engines certified to only one cycle. For 
medium and heavy heavy-duty engines certified as both tractor and 
vocational engines, measure CO2 emissions using the steady-
state duty cycle and the transient duty cycle (sometimes referred to as 
the FTP engine cycle), both of which are specified in 40 CFR part 86, 
subpart N. This is intended for engines that are designed for use in 
both tractor and vocational applications. For all other engines 
(including all spark-ignition engines), measure CO2 
emissions using the transient duty cycle specified in 40 CFR part 86, 
subpart N.
    (i) The CO2 standard for model year 2016 and later 
spark-ignition engines is 627 g/hp-hr.
    (ii) The following CO2 standards apply for compression-
ignition engines and all other engines (in g/hp-hr):

----------------------------------------------------------------------------------------------------------------
                                                                 Medium                    Medium
                                                 Light heavy- heavy-duty-- Heavy heavy- heavy-duty-- Heavy heavy-
                  Model years                        duty      vocational     duty--       tractor      duty--
                                                                            vocational                 tractor
----------------------------------------------------------------------------------------------------------------
2014-2016......................................          600          600          567          502          475
2017 and later.................................          576          576          555          487          460
----------------------------------------------------------------------------------------------------------------

     (2) The CH4 emission standard is 0.10 g/hp-hr when 
measured over the transient duty cycle specified in 40 CFR part 86, 
subpart N. This standard begins in model year 2014 for compression 
ignition engines and in model year 2016 for spark-ignition engines. 
Note that this standard applies for all fuel types just as the other 
standards of this section do.
    (3) The N2O emission standard for all model year 2014 
and later engines is 0.10 g/hp-hr when measured over the transient duty 
cycle specified in 40 CFR part 86, subpart N. This standard begins in 
model year 2014 for compression ignition engines and in model year 2016 
for spark-ignition engines.
    (4) This paragraph (a)(4) describes alternate emission standards 
for engines certified under 40 CFR 1037.150(m). The standards of 
paragraphs (a)(1) through (3) of this section do not apply for these 
engines. The standards in this paragraph (a)(4) apply for emissions 
measured with the engine installed in a complete vehicle consistent 
with the provisions of 40 CFR 1037.150(m)(6). The CO2 
standard for the engines equals the test result specified in 40 CFR 
1037.150(m)(6) multiplied by 1.10 and rounded to the nearest 0.1 g/
mile. The N2O and CH4 standards are both 0.05 g/
mile (or any alternate standards that apply to the corresponding 
vehicle test group). The only requirements of this part that apply to 
these engines are those in this paragraph (a)(4) and those in 
Sec. Sec.  1036.115 through 1036.135.

[[Page 57383]]

    (b) Family certification levels. You must specify a CO2 
Family Certification Level (FCL) for each engine family. The FCL may 
not be less than the certified emission level for the engine family. 
The CO2 Family Emission Limit (FEL) for the engine family is 
equal to the FCL multiplied by 1.03.
    (c) Averaging, banking, and trading. You may generate or use 
emission credits under the averaging, banking, and trading (ABT) 
program described in subpart H of this part for demonstrating 
compliance with CO2 emission standards. Credits (positive 
and negative) are calculated from the difference between the FCL and 
the applicable emission standard. As described in Sec.  1036.705, you 
may use CO2 credits to certify your engine families to FELs 
for N2O and/or CH4, instead of the 
N2O/CH4 standards of this section that otherwise 
apply. Except as specified in Sec. Sec.  1036.150 and 1036.705, you may 
not generate or use credits for N2O or CH4 
emissions.
    (d) Useful life. Your engines must meet the exhaust emission 
standards of this section throughout their full useful life, expressed 
in service miles or calendar years, whichever comes first. The useful 
life values applicable to the criteria pollutant standards of 40 CFR 
part 86 apply for the standards of this section.
    (e) Applicability for testing. The emission standards in this 
subpart apply as specified in this paragraph (e) to all duty-cycle 
testing (according to the applicable test cycles) of testable 
configurations, including certification, selective enforcement audits, 
and in-use testing. The CO2 FCLs serve as the CO2 
emission standards for the engine family with respect to certification 
and confirmatory testing instead of the standards specified in 
paragraph (a)(1) of this section. The FELs serve as the emission 
standards for the engine family with respect to all other testing. See 
Sec. Sec.  1036.235 and 1036.241 to determine which engine 
configurations within the engine family are subject to testing.
    (f) Multi-fuel engines. For dual-fuel, multi-fuel, and flexible-
fuel engines, perform exhaust testing on each fuel type (for example, 
gasoline and E85).
    (1) This paragraph (f)(1) applies where you demonstrate the 
relative amount of each fuel type that your engines consume in actual 
use. Based on your demonstration, we will specify a weighting factor 
and allow you to submit the weighted average of your emission results. 
For example, if you certify an E85 flexible-fuel engine and we 
determine the engine will produce one-half of its work from E85 and 
one-half of its work from gasoline, you may average your E85 and 
gasoline emission results.
    (2) If you certify your engine family to N2O and/or 
CH4 FELs the FELs apply for testing on all fuel types for 
which your engine is designed, to the same extent as criteria emission 
standards apply.

Sec.  1036.115  Other requirements.

    (a) The warranty and maintenance requirements, adjustable parameter 
provisions, and defeat device prohibition of 40 CFR part 86 apply with 
respect to the standards of this part.
    (b) [Reserved]

Sec.  1036.130  Installation instructions for vehicle manufacturers.

    (a) If you sell an engine for someone else to install in a vehicle, 
give the engine installer instructions for installing it consistent 
with the requirements of this part. Include all information necessary 
to ensure that an engine will be installed in its certified 
configuration.
    (b) Make sure these instructions have the following information:
    (1) Include the heading: ``Emission-related installation 
instructions''.
    (2) State: ``Failing to follow these instructions when installing a 
certified engine in a heavy-duty motor vehicle violates federal law, 
subject to fines or other penalties as described in the Clean Air 
Act.''
    (3) Provide all instructions needed to properly install the exhaust 
system and any other components.
    (4) Describe any necessary steps for installing any diagnostic 
system required under 40 CFR part 86.
    (5) Describe how your certification is limited for any type of 
application. For example, if you certify heavy heavy-duty engines to 
the CO2 standards using only steady-state testing, you must 
make clear that the engine may be installed only in tractors.
    (6) Describe any other instructions to make sure the installed 
engine will operate according to design specifications in your 
application for certification. This may include, for example, 
instructions for installing aftertreatment devices when installing the 
engines.
    (7) State: ``If you install the engine in a way that makes the 
engine's emission control information label hard to read during normal 
engine maintenance, you must place a duplicate label on the vehicle, as 
described in 40 CFR 1068.105.''
    (c) You do not need installation instructions for engines that you 
install in your own vehicles.
    (d) Provide instructions in writing or in an equivalent format. For 
example, you may post instructions on a publicly available Web site for 
downloading or printing. If you do not provide the instructions in 
writing, explain in your application for certification how you will 
ensure that each installer is informed of the installation 
requirements.

Sec.  1036.135  Labeling.

    Label your engines as described in 40 CFR 86.007-35(a)(3), with the 
following additional information:
    (a) [Reserved]
    (b) Identify the emission control system. Use terms and 
abbreviations as described in 40 CFR 1068.45 or other applicable 
conventions.
    (c) Identify any limitations on your certification. For example, if 
you certify heavy heavy-duty engines to the CO2 standards 
using only transient cycle testing, include the statement ``VOCATIONAL 
VEHICLES ONLY''.
    (d) You may ask us to approve modified labeling requirements in 
this part 1036 if you show that it is necessary or appropriate. We will 
approve your request if your alternate label is consistent with the 
requirements of this part. We may also specify modified labeling 
requirement to be consistent with the intent of 40 CFR part 1037.

Sec.  1036.140  Primary intended service class.

    You must identify a single primary intended service class for each 
compression-ignition engine family. Select the class that best 
describes vehicles for which you design and market the engine. The 
three primary intended service classes are light heavy-duty, medium 
heavy-duty, and heavy heavy-duty. Note that provisions that apply based 
on primary intended service class often treat spark-ignition engines as 
if they were a separate service class.
    (a) Light heavy-duty engines usually are not designed for rebuild 
and do not have cylinder liners. Vehicle body types in this group might 
include any heavy-duty vehicle built for a light-duty truck chassis, 
van trucks, multi-stop vans, motor homes and other recreational 
vehicles, and some straight trucks with a single rear axle. Typical 
applications would include personal transportation, light-load 
commercial delivery, passenger service, agriculture, and construction. 
The GVWR of these vehicles is normally below 19,500 pounds.
    (b) Medium heavy-duty engines may be designed for rebuild and may 
have cylinder liners. Vehicle body types in this group would typically 
include school buses, straight trucks with dual

[[Page 57384]]

rear axles, city tractors, and a variety of special purpose vehicles 
such as small dump trucks, and refuse trucks. Typical applications 
would include commercial short haul and intra-city delivery and pickup. 
Engines in this group are normally used in vehicles whose GVWR ranges 
from 19,500 to 33,000 pounds.
    (c) Heavy heavy-duty engines are designed for multiple rebuilds and 
have cylinder liners. Vehicles in this group are normally tractors, 
trucks, and buses used in inter-city, long-haul applications. These 
vehicles normally exceed 33,000 pounds GVWR.

Sec.  1036.150  Interim provisions.

    The provisions in this section apply instead of other provisions in 
this part.
    (a) Early banking of greenhouse gas emissions. You may generate 
CO2 emission credits for engines you certify in model year 
2013 (2015 for spark-ignition engines) to the standards of Sec.  
1036.108.
    (1) Except as specified in paragraph (a)(2) of this section, to 
generate early credits, you must certify your entire U.S.-directed 
production volume within that averaging set to these standards. This 
means that you may not generate early credits while you produce engines 
in the averaging set that are certified to the criteria pollutant 
standards but not to the greenhouse gas standards. Calculate emission 
credits as described in subpart H of this part relative to the standard 
that would apply for model year 2014 (2016 for spark-ignition engines).
    (2) You may generate early credits for an individual compression-
ignition engine family where you demonstrate that you have improved a 
model year 2013 engine model's CO2 emissions relative to its 
2012 baseline level and certify it to an FCL below the applicable 
standard. Calculate emission credits as described in subpart H of this 
part relative to the lesser of the standard that would apply for model 
year 2014 engines or the baseline engine's CO2 emission 
rate. Use the smaller U.S.-directed production volume of the 2013 
engine family or the 2012 baseline engine family. We will not allow you 
to generate emission credits under this paragraph (a)(2) unless we 
determine that your 2013 engine is the same engine as the 2012 baseline 
or that it replaces it.
    (3) You may bank credits equal to the surplus credits you generate 
under this paragraph (a) multiplied by 1.50. For example, if you have 
10 Mg of surplus credits for model year 2013, you may bank 15 Mg of 
credits. Credit deficits for an averaging set prior to model year 2014 
(2016 for spark-ignition engines) do not carry over to model year 2014 
(2016 for spark-ignition engines). We recommend that you notify us of 
your intent to use this provision before submitting your applications.
    (b) Model year 2014 N2O standards. In model year 2014 
and earlier, manufacturers may show compliance with the N2O 
standards using an engineering analysis. This allowance also applies 
for later families certified using carryover CO2 data from 
model 2014 consistent with Sec.  1036.235(d).
    (c) Engine cycle classification. Engines meeting the definition of 
spark-ignition, but regulated as diesel engines under 40 CFR part 86, 
must be certified to the requirements applicable to compression-
ignition engines under this part. Such engines are deemed to be 
compression-ignition engines for purposes of this part. Similarly, 
engines meeting the definition of compression-ignition, but regulated 
as Otto-cycle under 40 CFR part 86 must be certified to the 
requirements applicable to spark-ignition engines under this part. Such 
engines are deemed to be spark-ignition engines for purposes of this 
part.
    (d) Small manufacturers. Manufacturers meeting the small business 
criteria specified for ``Gasoline Engine and Engine Parts 
Manufacturing'' or ``Other Engine Equipment Manufacturers'' in 13 CFR 
121.201 are not subject to the greenhouse gas emission standards in 
Sec.  1036.108. Qualifying manufacturers must notify the Designated 
Compliance Officer before importing or introducing into U.S. commerce 
excluded engines. This notification must include a description of the 
manufacturer's qualification as a small business under 13 CFR 121.201. 
You must label your excluded vehicles with the statement: ``THIS ENGINE 
IS EXCLUDED UNDER 40 CFR 1037.150(c).''
    (e) Alternate phase-in standards. Where a manufacturer certifies 
all of its model year 2013 compression-ignition engines within a given 
primary intended service class to the applicable alternate standards of 
this paragraph (e), its compression-ignition engines within that 
primary intended service class are subject to the standards of this 
paragraph (e) for model years 2013 through 2016. This means that once a 
manufacturer chooses to certify a primary intended service class to the 
standards of this paragraph (e), it is not allowed to opt out of these 
standards. Engines certified to these standards are not eligible for 
early credits under paragraph (a) of this section.

----------------------------------------------------------------------------------------------------------------
               Tractors                      LHD Engines              MHD Engines              HHD Engines
----------------------------------------------------------------------------------------------------------------
Model Years 2013-2015................  NA.....................  512 g/hp-hr............  485 g/hp-hr.
Model Years 2016 and later \a\.......  NA.....................  487 g/hp-hr............  460 g/hp-hr.
----------------------------------------------------------------------------------------------------------------
Vocational                                   LHD Engines              MHD Engines              HHD Engines
----------------------------------------------------------------------------------------------------------------
Model Years 2013-2015................  618 g/hp-hr............  618 g/hp-hr............  577 g/hp-hr.
----------------------------------------------------------------------------------------------------------------
Model Years 2016 and later \a\.......  576 g/hp-hr............  576 g/hp-hr............  555 g/hp-hr.
----------------------------------------------------------------------------------------------------------------
\a\ Note: These alternate standards for 2016 and later are the same as the otherwise applicable standards for
  2017 and later.

    (f) Separate OBD families. This paragraph (f) applies where you 
separately certify engines for the purpose of applying OBD requirements 
(for engines used in vehicles under 14,000 pounds GVWR) from non-OBD 
engines that could be certified as a single engine family. You may 
treat the two engine families as a single engine family in certain 
respects for the purpose of this part, as follows:
    (1) This paragraph applies only where the two families are 
identical in all respects except for the engine ratings offered and the 
inclusion of OBD.
    (2) For purposes of this part and 40 CFR part 86, the two families 
remain two separate families except for the following:
    (i) Specify the testable configurations of the non-OBD engine 
family as the testable configurations for the OBD family.
    (ii) Submit the same CO2, N2O, and 
CH4 emission data for both engine families.
    (g) Assigned deterioration factors. You may use assigned 
deterioration factors (DFs) without performing your own durability 
emission tests or engineering analysis as follows:
    (1) You may use an assigned additive DF of 0.0 g/hp-hr for 
CO2 emissions from engines that do not use advanced or 
innovative technologies. If we determine it to be consistent with good 
engineering judgment, we may allow you to use an assigned additive DF 
of 0.0 g/hp-hr for CO2 emissions from your engines with 
advanced or innovative technologies.
    (2) You may use an assigned additive DF of 0.02 g/hp-hr for 
N2O emissions from any engine.
    (3) You may use an assigned additive DF of 0.02 g/hp-hr for 
CH4 emissions from any engine.
    (h) Advanced technology credits. If you generate credits from 
engines

[[Page 57385]]

certified for advanced technology you may multiply these credits by 
1.5, except that you may not apply this multiplier and the early-credit 
multiplier of paragraph (a) of this section.
    (i) CO2 credits for low N2O emissions. If you 
certify your model year 2014, 2015, or 2016 engines to an 
N2O FEL less than 0.04 g/hp-hr (provided you measure 
N2O emissions from your emission-data engines), you may 
generate additional CO2 credits under this paragraph (i). 
Calculate the additional CO2 credits from the following 
equation instead of the equation in Sec.  1036.705:

CO2 Credits (Mg) = (0.04 - FELN2O) [middot] (CF) 
[middot] (Volume) [middot] (UL) [middot] (10-6) [middot] 
(298)

Subpart C--Certifying Engine Families

Sec.  1036.205  What must I include in my application?

    Submit an application for certification as described in 40 CFR 
86.007-21, with the following additional information:
    (a) Describe the engine family's specifications and other basic 
parameters of the engine's design and emission controls with respect to 
compliance with the requirements of this part. Describe in detail all 
system components for controlling greenhouse gas emissions, including 
all auxiliary emission control devices (AECDs) and all fuel-system 
components you will install on any production or test engine. Identify 
the part number of each component you describe. For this paragraph (a), 
treat as separate AECDs any devices that modulate or activate 
differently from each other.
    (b) Describe any test equipment and procedures that you used if you 
performed any tests that did not also involve measurement of criteria 
pollutants. Describe any special or alternate test procedures you used 
(see 40 CFR 1065.10(c)).
    (c) Include the emission-related installation instructions you will 
provide if someone else installs your engines in their vehicles (see 
Sec.  1036.130).
    (d) Describe the label information specified in Sec.  1036.135. We 
may require you to include a copy of the label.
    (e) Identify the FCLs with which you are certifying engines in the 
engine family. The actual U.S.-directed production volume of 
configurations that have emission rates at or below the FCL must be at 
least one percent of your total actual (not projected) U.S.-directed 
production volume for the engine family. Identify configurations within 
the family that have emission rates at or below the FCL and meet the 
one percent requirement. For example, if your total U.S.-directed 
production volume for the engine family is 10,583, and the U.S.-
directed production volume for the tested rating is 75 engines, then 
you can comply with this provision by setting your FCL so that one more 
rating with a U.S.-directed production volume of at least 31 engines 
meets the FCL. Where applicable, also identify other testable 
configurations required under Sec.  1036.230(b)(2).
    (f) Identify the engine family's deterioration factors and describe 
how you developed them (see Sec.  1036.241). Present any test data you 
used for this.
    (g) Present emission data to show that you meet emission standards, 
as follows:
    (1) Present exhaust emission data for CO2, 
CH4, and N2O on an emission-data engine to show 
that your engines meet the applicable emission standards we specify in 
Sec.  1036.108. Show emission figures before and after applying 
deterioration factors for each engine. In addition to the composite 
results, show individual measurements for cold-start testing and hot-
start testing over the transient test cycle.
    (2) Note that Sec.  1036.235 allows you to submit an application in 
certain cases without new emission data.
    (h) State whether your certification is limited for certain 
engines. For example, if you certify heavy heavy-duty engines to the 
CO2 standards using only transient testing, the engines may 
be installed only in vocational vehicles.
    (i) Unconditionally certify that all the engines in the engine 
family comply with the requirements of this part, other referenced 
parts of the CFR, and the Clean Air Act. Note that Sec.  1036.235 
specifies which engines to test to show that engines in the entire 
family comply with the requirements of this part.
    (j) Include the information required by other subparts of this 
part. For example, include the information required by Sec.  1036.725 
if you participate in the ABT program.
    (k) Include the warranty statement and maintenance instructions if 
we request them.
    (l) Include other applicable information, such as information 
specified in this part or 40 CFR part 1068 related to requests for 
exemptions.
    (m) For imported engines or equipment, identify the following:
    (1) Describe your normal practice for importing engines. For 
example, this may include identifying the names and addresses of any 
agents you have authorized to import your engines. Engines imported by 
nonauthorized agents are not covered by your certificate.
    (2) The location of a test facility in the United States where you 
can test your engines if we select them for testing under a selective 
enforcement audit, as specified in 40 CFR part 1068, subpart E.

Sec.  1036.210  Preliminary approval before certification.

    If you send us information before you finish the application, we 
may review it and make any appropriate determinations, especially for 
questions related to engine family definitions, auxiliary emission 
control devices, adjustable parameters, deterioration factors, testing 
for service accumulation, and maintenance. Decisions made under this 
section are considered to be preliminary approval, subject to final 
review and approval. We will generally not reverse a decision where we 
have given you preliminary approval, unless we find new information 
supporting a different decision. If you request preliminary approval 
related to the upcoming model year or the model year after that, we 
will make best-efforts to make the appropriate determinations as soon 
as practicable. We will generally not provide preliminary approval 
related to a future model year more than two years ahead of time.

Sec.  1036.225  Amending my application for certification.

    Before we issue you a certificate of conformity, you may amend your 
application to include new or modified engine configurations, subject 
to the provisions of this section. After we have issued your 
certificate of conformity, but before the end of the model year, you 
may send us an amended application requesting that we include new or 
modified engine configurations within the scope of the certificate, 
subject to the provisions of this section. You must amend your 
application if any changes occur with respect to any information that 
is included or should be included in your application.
    (a) You must amend your application before you take any of the 
following actions:
    (1) Add an engine configuration to an engine family. In this case, 
the engine configuration added must be consistent with other engine 
configurations in the engine family with respect to the criteria listed 
in Sec.  1036.230.
    (2) Change an engine configuration already included in an engine 
family in a way that may affect emissions, or change any of the 
components you described in your application for certification. This 
includes production

[[Page 57386]]

and design changes that may affect emissions any time during the 
engine's lifetime.
    (3) Modify an FEL and FCL for an engine family as described in 
paragraph (f) of this section.
    (b) To amend your application for certification, send the relevant 
information to the Designated Compliance Officer.
    (1) Describe in detail the addition or change in the engine model 
or configuration you intend to make.
    (2) Include engineering evaluations or data showing that the 
amended engine family complies with all applicable requirements. You 
may do this by showing that the original emission-data engine is still 
appropriate for showing that the amended family complies with all 
applicable requirements.
    (3) If the original emission-data engine for the engine family is 
not appropriate to show compliance for the new or modified engine 
configuration, include new test data showing that the new or modified 
engine configuration meets the requirements of this part.
    (c) We may ask for more test data or engineering evaluations. You 
must give us these within 30 days after we request them.
    (d) For engine families already covered by a certificate of 
conformity, we will determine whether the existing certificate of 
conformity covers your newly added or modified engine. You may ask for 
a hearing if we deny your request (see Sec.  1036.820).
    (e) For engine families already covered by a certificate of 
conformity, you may start producing the new or modified engine 
configuration anytime after you send us your amended application and 
before we make a decision under paragraph (d) of this section. However, 
if we determine that the affected engines do not meet applicable 
requirements, we will notify you to cease production of the engines and 
may require you to recall the engines at no expense to the owner. 
Choosing to produce engines under this paragraph (e) is deemed to be 
consent to recall all engines that we determine do not meet applicable 
emission standards or other requirements and to remedy the 
nonconformity at no expense to the owner. If you do not provide 
information required under paragraph (c) of this section within 30 days 
after we request it, you must stop producing the new or modified 
engines.
    (f) You may ask us to approve a change to your FEL in certain cases 
after the start of production, but before the end of the model year. If 
you change an FEL for CO2, your FCL for CO2 is 
automatically set to your new FEL divided by 1.03. The changed FEL may 
not apply to engines you have already introduced into U.S. commerce, 
except as described in this paragraph (f). If we approve a changed FEL 
after the start of production, you must include the new FEL on the 
emission control information label for all engines produced after the 
change. You may ask us to approve a change to your FEL in the following 
cases:
    (1) You may ask to raise your FEL for your engine family at any 
time. In your request, you must show that you will still be able to 
meet the emission standards as specified in subparts B and H of this 
part. Use the appropriate FELs/FCLs with corresponding production 
volumes to calculate emission credits for the model year, as described 
in subpart H of this part.
    (2) You may ask to lower the FEL for your engine family only if you 
have test data from production engines showing that emissions are below 
the proposed lower FEL (or below the proposed FCL for CO2). 
The lower FEL/FCL applies only to engines you produce after we approve 
the new FEL/FCL. Use the appropriate FELs/FCLs with corresponding 
production volumes to calculate emission credits for the model year, as 
described in subpart H of this part.

Sec.  1036.230  Selecting engine families.

    See 40 CFR 86.001-24 for instructions on how to divide your product 
line into families of engines that are expected to have similar 
emission characteristics throughout the useful life. You must certify 
your engines to the standards of Sec.  1036.108 using the same engine 
families you use for criteria pollutants under 40 CFR part 86. The 
following provisions also apply:
    (a) Engines certified as hybrid engines or power packs may not be 
included in an engine family with engines with conventional 
powertrains. Note that this does not prevent you from including engines 
in a conventional family if they are used in hybrid vehicles, as long 
as you certify them conventionally.
    (b) If you certify engines in the family for use as both vocational 
and tractor engines, you must split your family into two separate 
subfamilies. Indicate in the application for certification that the 
engine family is to be split.
    (1) Calculate emission credits relative to the vocational engine 
standard for the number of engines sold into vocational applications 
and relative to the tractor engine standard for the number of engines 
sold into non-vocational tractor applications. You may assign the 
numbers and configurations of engines within the respective subfamilies 
at any time before submitting the end-of-year report required by Sec.  
1036.730. If the family participates in averaging, banking, or trading, 
you must identify the type of vehicle in which each engine is 
installed; we may alternatively allow you to use statistical methods to 
determine this for a fraction of your engines. Keep records to document 
this determination.
    (2) If you restrict use of the test configuration for your split 
family to only tractors, or only vocational vehicles, you must identify 
a second testable configuration for the other type of vehicle (or an 
unrestricted configuration). Identify this configuration in your 
application for certification. The FCL for the engine family applies 
for this configuration as well as the primary test configuration.
    (c) If you certify in separate engine families engines that could 
have been certified in vocational and tractor engine subfamilies in the 
same engine family, count the two families as one family for purposes 
of determining your obligations with respect to the OBD requirements 
and in-use testing requirements of 40 CFR part 86. Indicate in the 
applications for certification that the two engine families are covered 
by this paragraph (c).
    (d) Engine configurations within an engine family must use 
equivalent greenhouse gas emission controls. Unless we approve it, you 
may not produce nontested configurations without the same emission 
control hardware included on the tested configuration. We will only 
approve it if you demonstrate that the exclusion of the hardware does 
not increase greenhouse gas emissions.

Sec.  1036.235  Testing requirements for certification.

    This section describes the emission testing you must perform to 
show compliance with the greenhouse gas emission standards in Sec.  
1036.108.
    (a) Select a single emission-data engine from each engine family as 
specified in 40 CFR part 86. The standards of this part apply only with 
respect to emissions measured from this tested configuration and other 
configurations identified in Sec.  1036.205(e). Note that 
configurations identified in Sec.  1036.205(e) are considered to be 
``tested configurations'' whether or not you actually tested them for 
certification. However, you must apply the same (or equivalent) 
emission controls to all other engine configurations in the engine 
family.
    (b) Test your emission-data engines using the procedures and 
equipment specified in subpart F of this part. In the

[[Page 57387]]

case of dual-fuel and flexible-fuel engines, measure emissions when 
operating with each type of fuel for which you intend to certify the 
engine. Measure CO2, CH4, and N2O 
emissions using the specified duty cycle(s), including cold-start and 
hot-start testing as specified in 40 CFR part 86, subpart N. If you are 
certifying the engine for use in tractors, you must measure 
CO2 emissions using the SET cycle and measure 
CH4, and N2O emissions using the transient cycle. 
If you are certifying the engine for use in vocational applications, 
you must measure CO2, CH4, and N2O 
emissions using the specified transient duty cycle, including cold-
start and hot-start testing as specified in 40 CFR part 86, subpart N. 
Engines certified for use in tractors may also be used in vocational 
vehicles; however, you may not knowingly circumvent the intent of this 
part (to reduce in-use emissions of CO2) by certifying 
engines designed for vocational vehicles (and rarely used in tractors) 
to the SET and not the transient cycle. For example, we would generally 
not allow you to certify all your engines to the SET without certifying 
any to the transient cycle. You may certify your engine family for both 
tractor and vocational use by submitting CO2 emission data 
from both SET and transient cycle testing and specifying FCLs for both.
    (c) We may measure emissions from any of your emission-data 
engines.
    (1) We may decide to do the testing at your plant or any other 
facility. If we do this, you must deliver the engine to a test facility 
we designate. The engine you provide must include appropriate 
manifolds, aftertreatment devices, electronic control units, and other 
emission-related components not normally attached directly to the 
engine block. If we do the testing at your plant, you must schedule it 
as soon as possible and make available the instruments, personnel, and 
equipment we need.
    (2) If we measure emissions on your engine, the results of that 
testing become the official emission results for the engine. Unless we 
later invalidate these data, we may decide not to consider your data in 
determining if your engine family meets applicable requirements.
    (3) Before we test one of your engines, we may set its adjustable 
parameters to any point within the physically adjustable ranges.
    (4) Before we test one of your engines, we may calibrate it within 
normal production tolerances for anything we do not consider an 
adjustable parameter. For example, this would apply for an engine 
parameter that is subject to production variability because it is 
adjustable during production, but is not considered an adjustable 
parameter (as defined in Sec.  1036.801) because it is permanently 
sealed.
    (d) You may ask to use carryover emission data from a previous 
model year instead of doing new tests, but only if all the following 
are true:
    (1) The engine family from the previous model year differs from the 
current engine family only with respect to model year or other 
characteristics unrelated to emissions.
    (2) The emission-data engine from the previous model year remains 
the appropriate emission-data engine under paragraph (b) of this 
section.
    (3) The data show that the emission-data engine would meet all the 
requirements that apply to the engine family covered by the application 
for certification.
    (e) We may require you to test a second engine of the same 
configuration in addition to the engine tested under paragraph (a) of 
this section.
    (f) If you use an alternate test procedure under 40 CFR 1065.10 and 
later testing shows that such testing does not produce results that are 
equivalent to the procedures specified in subpart F of this part, we 
may reject data you generated using the alternate procedure.

Sec.  1036.241  Demonstrating compliance with greenhouse gas pollutant 
standards.

    (a) For purposes of certification, your engine family is considered 
in compliance with the emission standards in Sec.  1036.108 if all 
emission-data engines representing the tested configuration of that 
engine family have test results showing official emission results and 
deteriorated emission levels at or below the standards. Note that your 
FCLs are considered to be the applicable emission standards with which 
you must comply for certification.
    (b) Your engine family is deemed not to comply if any emission-data 
engine representing the tested configuration of that engine family has 
test results showing an official emission result or a deteriorated 
emission level for any pollutant that is above an applicable emission 
standard (generally the FCL). Note that you may increase your FCL if 
any certification test results exceed your initial FCL.
    (c) Apply deterioration factors to the measured emission levels for 
each pollutant to show compliance with the applicable emission 
standards. Your deterioration factors must take into account any 
available data from in-use testing with similar engines. Apply 
deterioration factors as follows:
    (1) Additive deterioration factor for greenhouse gas emissions. 
Except as specified in paragraph (c)(2) of this section, use an 
additive deterioration factor for exhaust emissions. An additive 
deterioration factor is the difference between exhaust emissions at the 
end of the useful life and exhaust emissions at the low-hour test 
point. In these cases, adjust the official emission results for each 
tested engine at the selected test point by adding the factor to the 
measured emissions. If the factor is less than zero, use zero. Additive 
deterioration factors must be specified to one more decimal place than 
the applicable standard.
    (2) Multiplicative deterioration factor for greenhouse gas 
emissions. Use a multiplicative deterioration factor for a pollutant if 
good engineering judgment calls for the deterioration factor for that 
pollutant to be the ratio of exhaust emissions at the end of the useful 
life to exhaust emissions at the low-hour test point. Adjust the 
official emission results for each tested engine at the selected test 
point by multiplying the measured emissions by the deterioration 
factor. If the factor is less than one, use one. A multiplicative 
deterioration factor may not be appropriate in cases where testing 
variability is significantly greater than engine-to-engine variability. 
Multiplicative deterioration factors must be specified to one more 
significant figure than the applicable standard.
    (3) Sawtooth deterioration patterns. The deterioration factors 
described in paragraphs (c)(1) and (2) of this section assume that the 
highest useful life emissions occur either at the end of useful life or 
at the low-hour test point. The provisions of this paragraph (c)(3) 
apply where good engineering judgment indicates that the highest useful 
life emissions will occur between these two points. For example, 
emissions may increase with service accumulation until a certain 
maintenance step is performed, then return to the low-hour emission 
levels and begin increasing again. Such a pattern may occur with 
battery-based electric hybrid engines. Base deterioration factors for 
engines with such emission patterns on the difference between (or ratio 
of) the point at which the highest emissions occur and the low-hour 
test point. Note that this applies for maintenance-related 
deterioration only where we allow such critical emission-related 
maintenance.
    (d) Collect emission data using measurements to one more decimal 
place than the applicable standard. Apply the deterioration factor to 
the official emission result, as described in

[[Page 57388]]

paragraph (c) of this section, then round the adjusted figure to the 
same number of decimal places as the emission standard. Compare the 
rounded emission levels to the emission standard for each emission-data 
engine.
    (e) If you identify more than one configuration in Sec.  
1036.205(e), we may test (or require you to test) any of the identified 
configurations. We may also require you to provide an engineering 
analysis that demonstrates that untested configurations listed in Sec.  
1036.205(e) comply with their FCL.

Sec.  1036.250  Reporting and recordkeeping for certification.

    (a) Within 90 days after the end of the model year, send the 
Designated Compliance Officer a report including the total U.S.-
directed production volume of engines you produced in each engine 
family during the model year (based on information available at the 
time of the report). Report the production by serial number and engine 
configuration. Small manufacturers may omit this requirement. You may 
combine this report with reports required under subpart H of this part.
    (b) Organize and maintain the following records:
    (1) A copy of all applications and any summary information you send 
us.
    (2) Any of the information we specify in Sec.  1036.205 that you 
were not required to include in your application.
    (c) Keep routine data from emission tests required by this part 
(such as test cell temperatures and relative humidity readings) for one 
year after we issue the associated certificate of conformity. Keep all 
other information specified in this section for eight years after we 
issue your certificate.
    (d) Store these records in any format and on any media, as long as 
you can promptly send us organized, written records in English if we 
ask for them. You must keep these records readily available. We may 
review them at any time.

Sec.  1036.255  What decisions may EPA make regarding my certificate of 
conformity?

    (a) If we determine your application is complete and shows that the 
engine family meets all the requirements of this part and the Act, we 
will issue a certificate of conformity for your engine family for that 
model year. We may make the approval subject to additional conditions.
    (b) We may deny your application for certification if we determine 
that your engine family fails to comply with emission standards or 
other requirements of this part or the Clean Air Act. We will base our 
decision on all available information. If we deny your application, we 
will explain why in writing.
    (c) In addition, we may deny your application or suspend or revoke 
your certificate if you do any of the following:
    (1) Refuse to comply with any testing or reporting requirements.
    (2) Submit false or incomplete information (paragraph (e) of this 
section applies if this is fraudulent). This includes doing anything 
after submission of your application to render any of the submitted 
information false or incomplete.
    (3) Render inaccurate any test data.
    (4) Deny us from completing authorized activities despite our 
presenting a warrant or court order (see 40 CFR 1068.20). This includes 
a failure to provide reasonable assistance. However, you may ask us to 
reconsider our decision by showing that your failure under this 
paragraph (c)(4) did not involve engines related to the certificate or 
application in question to a degree that would justify our decision.
    (5) Produce engines for importation into the United States at a 
location where local law prohibits us from carrying out authorized 
activities.
    (6) Fail to supply requested information or amend your application 
to include all engines being produced.
    (7) Take any action that otherwise circumvents the intent of the 
Act or this part, with respect to your engine family.
    (d) We may void the certificate of conformity for an engine family 
if you fail to keep records, send reports, or give us information as 
required under this part or the Act. Note that these are also 
violations of 40 CFR 1068.101(a)(2).
    (e) We may void your certificate if we find that you intentionally 
submitted false or incomplete information. This includes rendering 
submitted information false or incomplete after submission.
    (f) If we deny your application or suspend, revoke, or void your 
certificate, you may ask for a hearing (see Sec.  1036.820).

Subpart D--[Reserved]

Subpart E--In-use Testing

Sec.  1036.401  In-use testing.

    We may perform in-use testing of any engine family subject to the 
standards of this part, consistent with the provisions of Sec.  
1036.235. Note that this provisions does not affect your obligation to 
test your in-use engines as described in 40 CFR part 86, subpart T.

Subpart F--Test Procedures

Sec.  1036.501  How do I run a valid emission test?

    (a) Use the equipment and procedures specified in 40 CFR 86.1305 to 
determine whether engines meet the emission standards in Sec.  
1036.108.
    (b) You may use special or alternate procedures to the extent we 
allow them under 40 CFR 1065.10.
    (c) This subpart is addressed to you as a manufacturer, but it 
applies equally to anyone who does testing for you, and to us when we 
perform testing to determine if your engines meet emission standards.
    (d) For engines that use aftertreatment technology with infrequent 
regeneration events, invalidate any test interval in which such a 
regeneration event occurs with respect to CO2, 
N2O, and CH4 measurements.
    (e) Test hybrid engines as described in 40 CFR part 1065 and Sec.  
1036.525.
    (f) [Reserved]
    (g) If your engine requires special components for proper testing, 
you must provide any such components to us if we ask for them.

Sec.  1036.525  Hybrid engines.

    (a) If your engine system includes features that recover and store 
energy during engine motoring operation test the engine as described in 
paragraph (d) of this section. See Sec.  1036.615(a)(2) for engine 
systems intended to include features that recover and store energy from 
braking unrelated to engine motoring operation. For purposes of this 
section, features that recover energy between the engine and 
transmission are considered ``related to engine motoring''.
    (b) If you produce a hybrid engine designed with power take-off 
capability and sell the engine coupled with a transmission, you may 
calculate a reduction in CO2 emissions resulting from the 
power take-off operation as described in 40 CFR 1037.525. Use good 
engineering judgment to use the vehicle-based procedures to quantify 
the CO2 reduction for your engines.
    (c) The hardware that must be included in these tests is the 
engine, the hybrid electric motor, the rechargeable energy storage 
system (RESS) and the power electronics between the hybrid electric 
motor and the RESS. You may ask us to modify the provisions of this 
section to allow testing non-electric hybrid vehicles, consistent with 
good engineering judgment.
    (d) Measure emissions using the same procedures that apply for 
testing non-hybrid engines under this part, except as specified 
otherwise in this part and/

[[Page 57389]]

or 40 CFR part 1065. If you test hybrid engines using the SET, 
deactivate the hybrid features unless we have specified otherwise. The 
five differences that apply under this section are related to engine 
mapping, engine shutdown during the test cycle, calculating work, 
limits on braking energy, and state of charge constraints.
    (1) Map the engine as specified in 40 CFR 1065.510. This requires 
separate torque maps for the engine with and without the hybrid 
features active. For transient testing, denormalize the test cycle 
using the map generated with the hybrid feature active. For steady-
state testing, denormalize the test cycle using the map generated with 
the hybrid feature inactive.
    (2) If the engine will be configured in actual use to shut down 
automatically during idle operation, you may let the engine shut down 
during the idle portions of the test cycle.
    (3) Follow 40 CFR 1065.650(d) to calculate the work done over the 
cycle except as specified in this paragraph (d)(3). For the positive 
work over the cycle set negative power from hybrid to zero. For the 
negative work over the cycle set the positive power to zero and set the 
non-hybrid power to zero.
    (4)(i) Calculate brake energy fraction, xb, as the 
integrated negative work over the cycle divided by the integrated 
positive work over the cycle according to Equation 1036.525-1. 
Calculate the brake energy limit for the engine, xbl, 
according to Equation 1036.525-2. If xb is less than 
xbl, use the integrated positive work for your emission 
calculations. If the xb is greater than xbl use 
Equation 1036.525-3 to calculate the positive work done over the cycle. 
Use Wcycle as the integrated positive work when calculating 
brake-specific emissions. To avoid the need to delete extra brake work 
from positive work you may set an instantaneous brake target that will 
prevent xb from being larger than xbl.
[GRAPHIC] [TIFF OMITTED] TR15SE11.007

    (ii) The following definitions of terms apply for this paragraph 
(d)(4):
    xb = the brake energy fraction.
    Wneg = the negative work over the cycle.
    Wpos = the positive work over the cycle.
    xbl = the brake energy fraction limit.
    Pmax = the maximum power of the engine with the hybrid 
system engaged (kW).
    Wcycle = the work over the cycle when xb is 
greater than xbl.
    (iii) Note that these calculations are specified with SI units 
(such as kW), consistent with 40 CFR part 1065. Emission results are 
converted to g/hp-hr at the end of the calculations.
    (5) Correct for the net energy change of the energy storage device 
as described in 40 CFR 1066.501.

Sec.  1036.530  Calculating greenhouse gas emission rates.

    This section describes how to calculate official emission results 
for CO2, CH4, and N2O.
    (a) Calculate brake-specific emission rates for each applicable 
duty cycle as specified in 40 CFR 1065.650. Do not apply infrequent 
regeneration adjustment factors to your results.
    (b) Adjust CO2 emission rates calculated under paragraph 
(a) of this section for measured test fuel properties as specified in 
this paragraph (b) to obtain the official emission results. You are not 
required to apply this adjustment for fuels containing at least 75 
percent pure alcohol, such as E85. The purpose of this adjustment is to 
make official emission results independent of differences in test fuels 
within a fuel type. Use good engineering judgment to develop and apply 
testing protocols to minimize the impact of variations in test fuels.
    (1) For liquid fuels, determine the net energy content (Btu per 
pound of fuel) according to ASTM D4809 or ASTM D240 (both incorporated 
by reference in Sec.  1036.810) and carbon weight fraction 
(dimensionless) of your test fuel according to ASTM D5291 (incorporated 
by reference in Sec.  1036.810). (Note that we recommend using ASTM 
D4809.) For gaseous fuels, use good engineering judgment to determine 
the fuel's net energy content and carbon weight fraction. (Note: Net 
energy content is also sometimes known as lower heating value.) 
Calculate the test fuel's carbon-specific net energy content (Btu/lbC) 
by dividing the net energy content by the carbon fraction, expressed to 
at least five significant figures. You may perform these calculations 
using SI units with the following conversion factors: one Btu equals 
1055.06 Joules and one Btu/lb equals 0.0023260 MJ/kg.
    (2) If you control test fuel properties so that variations in the 
actual carbon-specific energy content are the same as or smaller than 
the repeatability of measuring carbon-specific energy content, you may 
use a constant value equal to the average carbon-specific energy 
content of your test fuel. Otherwise, use the measured value for the 
specific test fuel used for a given test. If you use a constant value, 
you must update or verify the value at least once per year, or after 
changes in test fuel suppliers or specifications.
    (3) Calculate the adjustment factor for carbon-specific net energy 
content by dividing the carbon-specific net energy content of your test 
fuel by the reference level in the following table, expressed to at 
least five decimal places. Note that as used in this section, the unit 
lbC means pound of carbon and kgC means kilogram of carbon.

------------------------------------------------------------------------
                                             Reference       Reference
                                              carbon-         carbon-
                Fuel type                  specific net    specific net
                                          energy content  energy content
                                             (Btu/lbC)       (MJ/kgC)
------------------------------------------------------------------------
Diesel fuel.............................          21,200         49.3112
Gasoline................................          21,700         50.4742
Natural Gas.............................          28,500         66.2910
LPG.....................................          24,300         56.5218
------------------------------------------------------------------------

[[Page 57390]]

     (4) Your official emission result equals your calculated brake-
specific emission rate multiplied by the adjustment factor specified in 
paragraph (b)(2) of this section. For example, if the net energy 
content and carbon fraction of your diesel test fuel are 18,400 Btu/lb 
and 0.870, the carbon-specific net energy content of the test fuel 
would be 21,149 Btu/lbC. The adjustment factor in the example above 
would be 0.99759 (21,149/21,200). If your brake-specific CO2 
emission rate was 630.0 g/hp-hr, your official emission result would be 
628.5 g/hp-hr.

Subpart G--Special Compliance Provisions

Sec.  1036.601  What compliance provisions apply to these engines?

    (a) Engine and equipment manufacturers, as well as owners, 
operators, and rebuilders of engines subject to the requirements of 
this part, and all other persons, must observe the provisions of this 
part, the provisions of the Clean Air Act, and the following provisions 
of 40 CFR part 1068:
    (1) The exemption and importation provisions of 40 CFR part 1068, 
subparts C and D, apply for engines subject to this part 1036, except 
that the hardship exemption provisions of 40 CFR 1068.245, 1068.250, 
and 1068.255 do not apply for motor vehicle engines.
    (2) Manufacturers may comply with the defect reporting requirements 
of 40 CFR 1068.501 instead of the defect reporting requirements of 40 
CFR part 85.
    (b) Engines exempted from the applicable standards of 40 CFR part 
86 are exempt from the standards of this part without request.

Sec.  1036.610  Innovative technology credits and adjustments for 
reducing greenhouse gas emissions.

    (a) You may ask us to apply the provisions of this section for 
CO2 emission reductions resulting from powertrain 
technologies that were not in common use with heavy-duty vehicles 
before model year 2010 that are not reflected in the specified test 
procedure. We will apply these provisions only for technologies that 
will result in a measurable, demonstrable, and verifiable real-world 
CO2 reduction.
    (b) The provisions of this section may be applied as either an 
improvement factor (used to adjust emission results) or as a separate 
credit, consistent with good engineering judgment. We recommend that 
you base your credit/adjustment on A to B testing of pairs of engines/
vehicles differing only with respect to the technology in question.
    (1) Calculate improvement factors as the ratio of in-use emissions 
with the technology divided by the in-use emissions without the 
technology. Adjust the emission results by multiplying by the 
improvement factor. Use the improvement-factor approach where good 
engineering judgment indicates that the actual benefit will be 
proportional to emissions measured over the test procedures specified 
in this part. For example, the benefits from technologies that reduce 
engine operation would generally be proportional to the engine's 
emission rate.
    (2) Calculate separate credits based on the difference between the 
in-use emission rate (g/ton-mile) with the technology and the in-use 
emission rate without the technology. Multiply this difference by the 
number of engines, standard payload, and useful life. We may also allow 
you to calculate the credits based on g/hp-hr emission rates. Use the 
separate-credit approach where good engineering judgment indicates that 
the actual benefit will not be proportional to emissions measured over 
the test procedures specified in this part.
    (3) We may require you to discount or otherwise adjust your 
improvement factor or credit to account for uncertainty or other 
relevant factors.
    (c) Send your request to the Designated Compliance Officer. Include 
a detailed description of the technology and a recommended test plan. 
Also state whether you recommend applying these provisions using the 
improvement-factor method or the separate-credit method. We recommend 
that you do not begin collecting test data (for submission to EPA) 
before contacting us. For technologies for which the vehicle 
manufacturer could also claim credits (such as transmissions in certain 
circumstances), we may require you to include a letter from the vehicle 
manufacturer stating that it will not seek credits for the same 
technology.
    (d) We may seek public comment on your request, consistent with the 
provisions of 40 CFR 86.1866-12(d)(3). However, we will generally not 
seek public comment on credits/adjustments based on A to B engine 
dynamometer testing, chassis testing, or in-use testing.

Sec.  1036.615  Engines with Rankine cycle waste heat recovery and 
hybrid powertrains.

    This section specifies how to generate advanced technology-specific 
emission credits for hybrid powertrains that include energy storage 
systems and regenerative braking (including regenerative engine 
braking) and for engines that include Rankine-cycle (or other bottoming 
cycle) exhaust energy recovery systems.
    (a) Hybrid powertrains. The following provisions apply for pre-
transmission and post-transmission hybrid powertrains:
    (1) Pre-transmission hybrid powertrains are those engine systems 
that include features that recover and store energy during engine 
motoring operation but not from the vehicle wheels. These powertrains 
are tested using the hybrid engine test procedures of 40 CFR part 1065 
or using the post-transmission test procedures in 40 CFR 1037.550.
    (2) Post-transmission hybrid powertrains are those powertrains that 
include features that recover and store energy from braking but that 
cannot function as hybrids without the transmission. These powertrains 
must have a single output shaft to the final drive and are tested by 
simulating the chassis test procedure applicable for hybrid vehicles 
under 40 CFR 1037.550. You need our approval before you begin testing.
    (b) Rankine engines. Test engines that include Rankine-cycle 
exhaust energy recovery systems according to the test procedures 
specified in subpart F of this part unless we approve alternate 
procedures.
    (c) Calculating credits. Calculate credits as specified in subpart 
H of this part. Credits generated from engines and powertrains 
certified under this section may be used in other averaging sets as 
described in Sec.  1036.740(d). Credits may not be generated under this 
section and 40 CFR 1037.615 for the same technology on the same 
vehicle.
    (d) Innovative technologies. You may certify using both provisions 
of this section and the innovative technology provisions of Sec.  
1036.610, provided you do not double count emission benefits.

Sec.  1036.620  Alternate CO2 standards based on model year 2011 
compression-ignition engines.

    For model years 2014 through 2016, you may certify your 
compression-ignition engines to the CO2 standards of this 
section instead of the CO2 standards in Sec.  1036.108. 
However, you may not certify engines to these alternate standards if 
they are part of an averaging set in which you carry a balance of 
banked credits. You may submit applications for certifications before 
using up banked credits in the averaging set, but such certificates 
will not become effective until you have used up (or retired) your 
banked credits in the averaging set. For purposes of this section, you 
are deemed to carry credits

[[Page 57391]]

in an averaging set if you carry credits from advanced technology that 
are allowed to be used in that averaging set.
    (a) The standards of this section are determined from the measured 
emission rate of the test engine of the applicable baseline 2011 engine 
family(ies) as described in paragraphs (b) and (c) of this section. 
Calculate the CO2 emission rate of the baseline test engine 
using the same equations used for showing compliance with the otherwise 
applicable standard. The alternate CO2 standard for light 
and medium heavy-duty vocational-certified engines (certified for 
CO2 using the transient cycle) is equal to the baseline 
emission rate multiplied by 0.975. The alternate CO2 
standard for tractor-certified engines (certified for CO2 
using the SET cycle) and all other heavy heavy-duty engines is equal to 
the baseline emission rate multiplied by 0.970. The in-use FEL for 
these engines is equal to the alternate standard multiplied by 1.03.
    (b) This paragraph (b) applies if you do not certify all your 
engine families in the averaging set to the alternate standards of this 
section. Identify separate baseline engine families for each engine 
family that you are certifying to the alternate standards of this 
section. For an engine family to be considered the baseline engine 
family, it must meet the following criteria:
    (1) It must have been certified to all applicable emission 
standards in model year 2011. If the baseline engine was certified to a 
NOX FEL above the standard and incorporated the same 
emission control technologies as the new engine family, you may adjust 
the baseline CO2 emission rate to be equivalent to an engine 
meeting the 0.20 g/hp-hr NOX standard (or your higher FEL as 
specified in this paragraph (b)(1)), using certification results from 
model years 2009 through 2011, consistent with good engineering 
judgment.
    (i) Use the following equation to relate model year 2009-2011 
NOX and CO2 emission rates (g/hp-hr): 
CO2 = a x log(NOX)+b.
    (ii) For model year 2014-2016 engines certified to NOX 
FELs above 0.20 g/hp-hr, correct the baseline CO2 emissions 
to the actual NOX FELs of the 2014-2016 engines.
    (iii) Calculate separate adjustments for transient and SET 
emissions.
    (2) The baseline configuration tested for certification must have 
the same engine displacement as the engines in the engine family being 
certified to the alternate standards, and its rated power must be 
within five percent of the highest rated power in the engine family 
being certified to the alternate standards.
    (3) The model year 2011 U.S.-directed production volume of the 
configuration tested must be at least one percent of the total 2011 
U.S.-directed production volume for the engine family.
    (4) The tested configuration must have cycle-weighted BSFC 
equivalent to or better than all other configurations in the engine 
family.
    (c) This paragraph (c) applies if you certify all your engine 
families in the primary intended service class to the alternate 
standards of this section. For purposes of this section, you may 
combine light heavy-duty and medium heavy-duty engines into a single 
averaging set. Determine your baseline CO2 emission rate as 
the production-weighted emission rate of the certified engine families 
you produced in the 2011 model year. If you produce engines for both 
tractors and vocational vehicles, treat them as separate averaging 
sets. Adjust the CO2 emission rates to be equivalent to an 
engine meeting the average NOX FEL of new engines (assuming 
engines certified to the 0.20 g/hp-hr NOX standard have a 
NOX FEL equal to 0.20 g/hp-hr), as described in paragraph 
(b)(1) of this section.
    (d) Include the following statement on the emission control 
information label: ``THIS ENGINE WAS CERTIFIED TO AN ALTERNATE 
CO2 STANDARD UNDER Sec.  1036.620.''
    (e) You may not bank CO2 emission credits for any engine 
family in the same averaging set and model year in which you certify 
engines to the standards of this section. You may not bank any advanced 
technology credits in any averaging set for the model year you certify 
under this section (since such credits would be available for use in 
this averaging set). Note that the provisions of Sec.  1036.745 apply 
for deficits generated with respect to the standards of this section.
    (f) You need our approval before you may certify engines under this 
section, especially with respect to the numerical value of the 
alternate standards. We will not approve your request if we determine 
that you manipulated your engine families or test engine configurations 
to certify to less stringent standards, or that you otherwise have not 
acted in good faith. You must keep and provide to us any information we 
need to determine that your engine families meet the requirements of 
this section. Keep these records for at least five years after you stop 
producing engines certified under this section.

Sec.  1036.625  In-use compliance with family emission limits (FELs).

    You may ask us to apply a higher in-use FEL for certain in-use 
engines, subject to the provisions of this section. Note that Sec.  
1036.225 contains provisions related to changing FELs during a model 
year.
    (a) Purpose. This section is intended to address circumstances in 
which it is in the public interest to apply a higher in-use FEL based 
on forfeiting an appropriate number of emission credits.
    (b) FELs. When applying higher in-use FELs to your engines, we 
would intend to accurately reflect the actual in-use performance of 
your engines, consistent with the specified testing provisions of this 
part.
    (c) Equivalent families. We may apply the higher FELs to other 
families in other model years if they used equivalent emission 
controls.
    (d) Credit forfeiture. Where we specify higher in-use FELs under 
this section, you must forfeit CO2 emission credits based on 
the difference between the in-use FEL and the otherwise applicable FEL. 
Calculate the amount of credits to be forfeited using the applicable 
equation in Sec.  1036.705, by substituting the otherwise applicable 
FEL for the standard and the in-use FEL for the otherwise applicable 
FEL.
    (e) Requests. Submit your request to the Designated Compliance 
Officer. Include the following in your request:
    (1) The engine family name and model year of the engines affected.
    (2) A list of other engine families/model years that may be 
affected.
    (3) The otherwise applicable FEL for the engine families along with 
your recommendations for higher in-use FELs.
    (4) Your source of credits for forfeiture.
    (f) Relation to recall. You may not request higher in-use FELs for 
any engine families for which we have made a determination of 
nonconformance and ordered a recall. You may, however, make such 
requests for engine families for which you are performing a voluntary 
emission recall.
    (g) Approval. We may approve your request if we determine that you 
meet the requirements of this section and such approval is in the 
public interest. We may include appropriate conditions with our 
approval or we may approve your request with modifications.

Subpart H--Averaging, Banking, and Trading for Certification

Sec.  1036.701  General provisions.

    (a) You may average, bank, and trade (ABT) emission credits for 
purposes of

[[Page 57392]]

certification as described in this subpart and in subpart B of this 
part to show compliance with the standards of Sec.  1036.108. 
Participation in this program is voluntary. (Note: As described in 
subpart B of this part, you must assign an FCL to all engine families, 
whether or not they participate in the ABT provisions of this subpart.)
    (b) [Reserved]
    (c) The definitions of subpart I of this part apply to this 
subpart. The following definitions also apply:
    (1) Actual emission credits means emission credits you have 
generated that we have verified by reviewing your final report.
    (2) Averaging set means a set of engines in which emission credits 
may be exchanged. Credits generated by one engine may only be used by 
other engines in the same averaging set. See Sec.  1036.740.
    (3) Broker means any entity that facilitates a trade of emission 
credits between a buyer and seller.
    (4) Buyer means the entity that receives emission credits as a 
result of a trade.
    (5) Reserved emission credits means emission credits you have 
generated that we have not yet verified by reviewing your final report.
    (6) Seller means the entity that provides emission credits during a 
trade.
    (7) Standard means the emission standard that applies under subpart 
B of this part for engines not participating in the ABT program of this 
subpart.
    (8) Trade means to exchange emission credits, either as a buyer or 
seller.
    (d) Emission credits may be exchanged only within an averaging set 
as specified in Sec.  1036.740.
    (e) You may not use emission credits generated under this subpart 
to offset any emissions that exceed an FCL or standard. This applies 
for all testing, including certification testing, in-use testing, 
selective enforcement audits, and other production-line testing. 
However, if emissions from an engine exceed an FCL or standard (for 
example, during a selective enforcement audit), you may use emission 
credits to recertify the engine family with a higher FCL that applies 
only to future production.
    (f) Emission credits may be used in the model year they are 
generated. Surplus emission credits may be banked for future model 
years. Surplus emission credits may sometimes be used for past model 
years, as described in Sec.  1036.745.
    (g) You may increase or decrease an FCL during the model year by 
amending your application for certification under Sec.  1036.225. The 
new FCL may apply only to engines you have not already introduced into 
commerce.
    (h) You may trade emission credits generated from any number of 
your engines to the engine purchasers or other parties to retire the 
credits. Identify any such credits in the reports described in Sec.  
1036.730. Engines must comply with the applicable FELs even if you 
donate or sell the corresponding emission credits under this paragraph 
(h). Those credits may no longer be used by anyone to demonstrate 
compliance with any EPA emission standards.
    (i) See Sec.  1036.740 for special credit provisions that apply for 
credits generated under Sec.  1036.615 or 40 CFR 1037.104(d)(7) or 
1037.615.
    (j) Unless the regulations explicitly allow it, you may not 
calculate credits more than once for any emission reduction. For 
example, if you generate CO2 emission credits for a hybrid 
engine under this part for a given vehicle, no one may generate 
CO2 emission credits for that same hybrid engine and vehicle 
under 40 CFR part 1037. However, credits could be generated for 
identical vehicles using engines that did not generate credits under 
this part.

Sec.  1036.705  Generating and calculating emission credits.

    (a) The provisions of this section apply separately for calculating 
emission credits for each pollutant.
    (b) For each participating family, calculate positive or negative 
emission credits relative to the otherwise applicable emission standard 
based on the engine family's FCL for greenhouse gases. If your engine 
family is certified to both the vocational and tractor engine 
standards, calculate credits separately for the vocational engines and 
the tractor engines (as specified in paragraph (b)(3) of this section). 
Calculate positive emission credits for a family that has an FCL below 
the standard. Calculate negative emission credits for a family that has 
an FCL above the standard.
    Sum your positive and negative credits for the model year before 
rounding. Round the sum of emission credits to the nearest megagram 
(Mg), using consistent units throughout the following equations:
    (1) For vocational engines:
    Emission credits (Mg) = (Std-FCL) [middot] (CF) [middot] (Volume) 
[middot] (UL) [middot] (10-6)

Where:

    Std = the emission standard, in g/hp-hr, that applies under 
subpart B of this part for engines not participating in the ABT 
program of this subpart (the ``otherwise applicable standard'').
    FCL = the Family Certification Level for the engine family, in 
g/hp-hr, measured over the transient duty cycle, rounded to the same 
number of decimal places as the emission standard.
    CF = a transient cycle conversion factor (hp-hr/mile), 
calculated by dividing the total (integrated) horsepower-hour over 
the duty cycle (average of vocational engine configurations weighted 
by their production volumes) by 6.3 miles for spark-ignition engines 
and 6.5 miles for compression-ignition engines. This represents the 
average work performed by vocational engines in the family over the 
mileage represented by operation over the duty cycle.
    Volume = the number of vocational engines eligible to 
participate in the averaging, banking, and trading program within 
the given engine family during the model year, as described in 
paragraph (c) of this section.
    UL = the useful life for the given engine family, in miles.

    (2) For tractor engines:
    Emission credits (Mg) = (Std-FCL) [middot] (CF) [middot] (Volume) 
[middot] (UL) [middot] (10-6)

Where:

    Std = the emission standard, in g/hp-hr, that applies under 
subpart B of this part for engines not participating in the ABT 
program of this subpart (the ``otherwise applicable standard'').
    FCL = the Family Certification Level for the engine family, in 
g/hp-hr, measured over the SET duty cycle rounded to the same number 
of decimal places as the emission standard.
    CF = a transient cycle conversion factor (hp-hr/mile), 
calculated by dividing the total (integrated) horsepower-hour over 
the duty cycle (average of tractor-engine configurations weighted by 
their production volumes) by 6.3 miles for spark-ignition engines 
and 6.5 miles for compression-ignition engines. This represents the 
average work performed by tractor engines in the family over the 
mileage represented by operation over the duty cycle. Note that this 
calculation requires you to use the transient cycle conversion 
factor even for engines certified to SET-based standards. Volume = 
the number of tractor engines eligible to participate in the 
averaging, banking, and trading program within the given engine 
family during the model year, as described in paragraph (c) of this 
section.
    UL = the useful life for the given engine family, in miles.

    (3) For engine families certified to both the vocational and 
tractor engine standards, we may allow you to use statistical methods 
to estimate the total production volumes where a small fraction of the 
engines cannot be tracked precisely.
    (4) You may not generate emission credits for tractor engines 
(i.e., engines not certified to the transient cycle for CO2) 
installed in vocational vehicles (including vocational tractors 
certified pursuant to 40 CFR 1037.630 or exempted pursuant to 40 CFR 
1037.631). We will waive this requirement where you demonstrate

[[Page 57393]]

that less than five percent of the engines in your tractor family were 
installed in vocational vehicles. For example, if you know that 96 
percent of your tractor engines were installed in non-vocational 
tractors, but cannot determine the vehicle type for the remaining four 
percent, you may generate credits for all the engines in the family.
    (c) As described in Sec.  1036.730, compliance with the 
requirements of this subpart is determined at the end of the model year 
based on actual U.S.-directed production volumes. Keep appropriate 
records to document these production volumes. Do not include any of the 
following engines to calculate emission credits:
    (1) Engines that you do not certify to the CO2 standards 
of this part because they are permanently exempted under subpart G of 
this part or under 40 CFR part 1068.
    (2) Exported engines.
    (3) Engines not subject to the requirements of this part, such as 
those excluded under Sec.  1036.5. For example, do not include engines 
used in vehicles certified to the greenhouse gas standards of 40 CFR 
1037.104.
    (4) [Reserved]
    (5) Any other engines if we indicate elsewhere in this part 1036 
that they are not to be included in the calculations of this subpart.
    (d) You may use CO2 emission credits to show compliance 
with CH4 and/or N2O FELs instead of the otherwise 
applicable emission standards. To do this, calculate the CH4 
and/or N2O emission credits needed (negative credits) using 
the equation in paragraph (b) of this section, using the FEL(s) you 
specify for your engines during certification instead of the FCL. You 
must use 25 Mg of positive CO2 credits to offset 1 Mg of 
negative CH4 credits. You must use 298 Mg of positive 
CO2 credits to offset 1 Mg of negative N2O 
credits.

Sec.  1036.710  Averaging.

    (a) Averaging is the exchange of emission credits among your engine 
families. You may average emission credits only within the same 
averaging set.
    (b) You may certify one or more engine families to an FCL above the 
applicable standard, subject to any applicable FEL caps and other the 
provisions in subpart B of this part, if you show in your application 
for certification that your projected balance of all emission-credit 
transactions in that model year is greater than or equal to zero, or 
that a negative balance is allowed under Sec.  1036.745.
    (c) If you certify an engine family to an FCL that exceeds the 
otherwise applicable standard, you must obtain enough emission credits 
to offset the engine family's deficit by the due date for the final 
report required in Sec.  1036.730. The emission credits used to address 
the deficit may come from your other engine families that generate 
emission credits in the same model year (or from later model years as 
specified in Sec.  1036.745), from emission credits you have banked, or 
from emission credits you obtain through trading.

Sec.  1036.715  Banking.

    (a) Banking is the retention of surplus emission credits by the 
manufacturer generating the emission credits for use in future model 
years for averaging or trading.
    (b) You may designate any emission credits you plan to bank in the 
reports you submit under Sec.  1036.730 as reserved credits. During the 
model year and before the due date for the final report, you may 
designate your reserved emission credits for averaging or trading.
    (c) Reserved credits become actual emission credits when you submit 
your final report. However, we may revoke these emission credits if we 
are unable to verify them after reviewing your reports or auditing your 
records.
    (d) Banked credits retain the designation of the averaging set in 
which they were generated.

Sec.  1036.720  Trading.

    (a) Trading is the exchange of emission credits between 
manufacturers, or the transfer of credits to another party to retire 
them. You may use traded emission credits for averaging, banking, or 
further trading transactions. Traded emission credits remain subject to 
the averaging-set restrictions based on the averaging set in which they 
were generated.
    (b) You may trade actual emission credits as described in this 
subpart. You may also trade reserved emission credits, but we may 
revoke these emission credits based on our review of your records or 
reports or those of the company with which you traded emission credits. 
You may trade banked credits within an averaging set to any certifying 
manufacturer.
    (c) If a negative emission credit balance results from a 
transaction, both the buyer and seller are liable, except in cases we 
deem to involve fraud. See Sec.  1036.255(e) for cases involving fraud. 
We may void the certificates of all engine families participating in a 
trade that results in a manufacturer having a negative balance of 
emission credits. See Sec.  1036.745.

Sec.  1036.725  What must I include in my application for 
certification?

    (a) You must declare in your application for certification your 
intent to use the provisions of this subpart for each engine family 
that will be certified using the ABT program. You must also declare the 
FELs/FCL you select for the engine family for each pollutant for which 
you are using the ABT program. Your FELs must comply with the 
specifications of subpart B of this part, including the FEL caps. FELs/
FCL must be expressed to the same number of decimal places as the 
applicable standards.
    (b) Include the following in your application for certification:
    (1) A statement that, to the best of your belief, you will not have 
a negative balance of emission credits for any averaging set when all 
emission credits are calculated at the end of the year; or a statement 
that you will have a negative balance of emission credits for one or 
more averaging sets, but that it is allowed under Sec.  1036.745.
    (2) Detailed calculations of projected emission credits (positive 
or negative) based on projected U.S.-directed production volumes. We 
may require you to include similar calculations from your other engine 
families to project your net credit balances for the model year. If you 
project negative emission credits for a family, state the source of 
positive emission credits you expect to use to offset the negative 
emission credits.

Sec.  1036.730  ABT reports.

    (a) If any of your engine families are certified using the ABT 
provisions of this subpart, you must send an end-of-year report within 
90 days after the end of the model year and a final report within 270 
days after the end of the model year.
    (b) Your end-of-year and final reports must include the following 
information for each engine family participating in the ABT program:
    (1) Engine-family designation and averaging set.
    (2) The emission standards that would otherwise apply to the engine 
family.
    (3) The FCL for each pollutant. If you change the FCL after the 
start of production, identify the date that you started using the new 
FCL and/or give the engine identification number for the first engine 
covered by the new FCL. In this case, identify each applicable FCL and 
calculate the positive or negative emission credits as specified in 
Sec.  1036.225.

[[Page 57394]]

    (4) The projected and actual U.S.-directed production volumes for 
the model year. If you changed an FCL during the model year, identify 
the actual production volume associated with each FCL.
    (5) The transient cycle conversion factor for each engine 
configuration as described in Sec.  1036.705.
    (6) Useful life.
    (7) Calculated positive or negative emission credits for the whole 
engine family. Identify any emission credits that you traded, as 
described in paragraph (d)(1) of this section.
    (c) Your end-of-year and final reports must include the following 
additional information:
    (1) Show that your net balance of emission credits from all your 
participating engine families in each averaging set in the applicable 
model year is not negative, except as allowed under Sec.  1036.745.
    (2) State whether you will reserve any emission credits for 
banking.
    (3) State that the report's contents are accurate.
    (d) If you trade emission credits, you must send us a report within 
90 days after the transaction, as follows:
    (1) As the seller, you must include the following information in 
your report:
    (i) The corporate names of the buyer and any brokers.
    (ii) A copy of any contracts related to the trade.
    (iii) The engine families that generated emission credits for the 
trade, including the number of emission credits from each family.
    (2) As the buyer, you must include the following information in 
your report:
    (i) The corporate names of the seller and any brokers.
    (ii) A copy of any contracts related to the trade.
    (iii) How you intend to use the emission credits, including the 
number of emission credits you intend to apply to each engine family 
(if known).
    (e) Send your reports electronically to the Designated Compliance 
Officer using an approved information format. If you want to use a 
different format, send us a written request with justification for a 
waiver.
    (f) Correct errors in your end-of-year report or final report as 
follows:
    (1) You may correct any errors in your end-of-year report when you 
prepare the final report, as long as you send us the final report by 
the time it is due.
    (2) If you or we determine within 270 days after the end of the 
model year that errors mistakenly decreased your balance of emission 
credits, you may correct the errors and recalculate the balance of 
emission credits. You may not make these corrections for errors that 
are determined more than 270 days after the end of the model year. If 
you report a negative balance of emission credits, we may disallow 
corrections under this paragraph (f)(2).
    (3) If you or we determine anytime that errors mistakenly increased 
your balance of emission credits, you must correct the errors and 
recalculate the balance of emission credits.

Sec.  1036.735  Recordkeeping.

    (a) You must organize and maintain your records as described in 
this section. We may review your records at any time.
    (b) Keep the records required by this section for at least eight 
years after the due date for the end-of-year report. You may not use 
emission credits for any engines if you do not keep all the records 
required under this section. You must therefore keep these records to 
continue to bank valid credits. Store these records in any format and 
on any media, as long as you can promptly send us organized, written 
records in English if we ask for them. You must keep these records 
readily available. We may review them at any time.
    (c) Keep a copy of the reports we require in Sec. Sec.  1036.725 
and 1036.730.
    (d) Keep records of the engine identification number (usually the 
serial number) for each engine you produce that generates or uses 
emission credits under the ABT program. You may identify these numbers 
as a range. If you change the FEL after the start of production, 
identify the date you started using each FCL and the range of engine 
identification numbers associated with each FCL. You must also identify 
the purchaser and destination for each engine you produce to the extent 
this information is available.
    (e) We may require you to keep additional records or to send us 
relevant information not required by this section in accordance with 
the Clean Air Act.

Sec.  1036.740  Restrictions for using emission credits.

    The following restrictions apply for using emission credits:
    (a) Averaging sets. Except as specified in paragraph (c) of this 
section, emission credits may be exchanged only within an following 
averaging sets There are four principal averaging sets for engines 
subject to this subpart:
    (1) Spark-ignition engines.
    (2) Compression-ignition light heavy-duty engines.
    (3) Compression-ignition medium heavy-duty engines.
    (4) Compression-ignition heavy heavy-duty engines.
    (b) Applying credits to prior year deficits. Where your credit 
balance for the previous year is negative, you may apply credits to 
that credit deficit only after meeting your credit obligations for the 
current year.
    (c) Credits from hybrid engines and other advanced technologies. 
The averaging set restrictions of paragraph (a) of this section do not 
apply for credits generated under Sec.  1036.615 or 40 CFR 
1037.104(d)(7) or 1037.615 from hybrid power systems with regenerative 
braking, or from other advanced technologies. Such credits may also be 
used under 40 CFR part 1037.
    (1) The maximum amount of credits you may bring into the following 
service class groups is 60,000 Mg per model year:
    (i) Spark-ignition engines, light heavy-duty compression-ignition 
engines, and light heavy-duty vehicles. This group comprises the 
averaging sets listed in paragraphs (a)(1) and (2) of this section and 
the averaging set listed in 40 CFR 1037.740(a)(1).
    (ii) Medium heavy-duty compression-ignition engines and medium 
heavy-duty vehicles. This group comprises the averaging sets listed in 
paragraph (a)(3) of this section and 40 CFR 1037.740(a)(2).
    (iii) Heavy heavy-duty compression-ignition engines and heavy 
heavy-duty vehicles. This group comprises the averaging sets listed in 
paragraph (a)(4) of this section and 40 CFR 1037.740(a)(3).
    (2) The limit specified in paragraph (c)(1) of this section does 
not limit the amount of advanced technology credits that can be used 
within a service class group if they were generated in that same 
service class group.
    (d) Credit life. Credits expire after five years.
    (e) Other restrictions. Other sections of this part specify 
additional restrictions for using emission credits under certain 
special provisions.

Sec.  1036.745  End-of-year CO2 credit deficits.

    Except as allowed by this section, we may void the certificate of 
any engine family certified to an FCL above the applicable standard for 
which you do not have sufficient credits by the deadline for submitting 
the final report.
    (a) Your certificate for an engine family for which you do not have 
sufficient CO2 credits will not be void if you remedy the 
deficit with surplus credits within three model years. For example, if 
you have a credit deficit of 500 Mg for an engine family at the end of 
model year 2015, you must generate (or otherwise obtain) a surplus of 
at

[[Page 57395]]

least 500 Mg in that same averaging set by the end of model year 2018.
    (b) You may not bank or trade away CO2 credits in the 
averaging set in any model year in which you have a deficit.
    (c) You may apply only surplus credits to your deficit. You may not 
apply credits to a deficit from an earlier model year if they were 
generated in a model year for which any of your engine families for 
that averaging set had an end-of-year credit deficit.
    (d) If you do not remedy the deficit with surplus credits within 
three model years, we may void your certificate for that engine family. 
We may void the certificate based on your end-of-year report. Note that 
voiding a certificate applies ab initio. Where the net deficit is less 
than the total amount of negative credits originally generated by the 
family, we will void the certificate only with respect to the number of 
engines needed to reach the amount of the net deficit. For example, if 
the original engine family generated 500 Mg of negative credits, and 
the manufacturer's net deficit after three years was 250 Mg, we would 
void the certificate with respect to half of the engines in the family.

Sec.  1036.750  What can happen if I do not comply with the provisions 
of this subpart?

    (a) For each engine family participating in the ABT program, the 
certificate of conformity is conditioned upon full compliance with the 
provisions of this subpart during and after the model year. You are 
responsible to establish to our satisfaction that you fully comply with 
applicable requirements. We may void the certificate of conformity for 
an engine family if you fail to comply with any provisions of this 
subpart.
    (b) You may certify your engine family to an FCL above an 
applicable standard based on a projection that you will have enough 
emission credits to offset the deficit for the engine family. See Sec.  
1036.745 for provisions specifying what happens if you cannot show in 
your final report that you have enough actual emission credits to 
offset a deficit for any pollutant in an engine family.
    (c) We may void the certificate of conformity for an engine family 
if you fail to keep records, send reports, or give us information we 
request. Note that failing to keep records, send reports, or give us 
information we request is also a violation of 42 U.S.C. 7522(a)(2).
    (d) You may ask for a hearing if we void your certificate under 
this section (see Sec.  1036.820).

Sec.  1036.755  Information provided to the Department of 
Transportation.

    After receipt of each manufacturer's final report as specified in 
Sec.  1036.730 and completion of any verification testing required to 
validate the manufacturer's submitted final data, we will issue a 
report to the Department of Transportation with CO2 emission 
information and will verify the accuracy of each manufacturer's 
equivalent fuel consumption data that required by NHTSA under 49 CFR 
535.8. We will send a report to DOT for each engine manufacturer based 
on each regulatory category and subcategory, including sufficient 
information for NHTSA to determine fuel consumption and associated 
credit values. See 49 CFR 535.8 to determine if NHTSA deems submission 
of this information to EPA to also be a submission to NHTSA.

Subpart I--Definitions and Other Reference Information

Sec.  1036.801  Definitions.

    The following definitions apply to this part. The definitions apply 
to all subparts unless we note otherwise. All undefined terms have the 
meaning the Act gives to them. The definitions follow:
    Act means the Clean Air Act, as amended, 42 U.S.C. 7401-7671q.
    Adjustable parameter has the meaning given in 40 CFR part 86.
    Advanced technology means technology certified under Sec.  
1036.615, 40 CFR 1037.104(d)(7) or 1037.615.
    Aftertreatment means relating to a catalytic converter, particulate 
filter, or any other system, component, or technology mounted 
downstream of the exhaust valve (or exhaust port) whose design function 
is to decrease emissions in the engine exhaust before it is exhausted 
to the environment. Exhaust-gas recirculation (EGR) and turbochargers 
are not aftertreatment.
    Aircraft means any vehicle capable of sustained air travel above 
treetop heights.
    Alcohol-fueled engine mean an engine that is designed to run using 
an alcohol fuel. For purposes of this definition, alcohol fuels do not 
include fuels with a nominal alcohol content below 25 percent by 
volume.
    Auxiliary emission control device means any element of design that 
senses temperature, motive speed, engine RPM, transmission gear, or any 
other parameter for the purpose of activating, modulating, delaying, or 
deactivating the operation of any part of the emission control system.
    Averaging set has the meaning given in Sec.  1036.740.
    Calibration means the set of specifications and tolerances specific 
to a particular design, version, or application of a component or 
assembly capable of functionally describing its operation over its 
working range.
    Carryover means relating to certification based on emission data 
generated from an earlier model year as described in Sec.  1036.235(d).
    Certification means relating to the process of obtaining a 
certificate of conformity for an engine family that complies with the 
emission standards and requirements in this part.
    Certified emission level means the highest deteriorated emission 
level in an engine family for a given pollutant from the applicable 
transient and/or steady-state testing, rounded to the same number of 
decimal places as the applicable standard. Note that you may have two 
certified emission levels for CO2 if you certify a family 
for both vocational and tractor use.
    Complete vehicle means a vehicle meeting the definition of complete 
vehicle in 40 CFR 1037.801 when it is first sold as a vehicle. For 
example, where a vehicle manufacturer sells an incomplete vehicle to a 
secondary manufacturer, the vehicle is not a complete vehicle under 
this part, even after its final assembly.
    Compression-ignition means relating to a type of reciprocating, 
internal-combustion engine that is not a spark-ignition engine.
    Crankcase emissions means airborne substances emitted to the 
atmosphere from any part of the engine crankcase's ventilation or 
lubrication systems. The crankcase is the housing for the crankshaft 
and other related internal parts.
    Criteria pollutants means emissions of NOX, HC, PM, and 
CO. Note that these pollutants are also sometimes described 
collectively as ``non-greenhouse gas pollutants'', although they do not 
necessarily have negligible global warming potentials.
    Designated Compliance Officer means the Manager, Heavy-Duty and 
Nonroad Engine Group (6405-J), U.S. Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460.
    Designated Enforcement Officer means the Director, Air Enforcement 
Division (2242A), U.S. Environmental Protection Agency, 1200 
Pennsylvania Ave., NW., Washington, DC 20460.
    Deteriorated emission level means the emission level that results 
from applying the appropriate deterioration factor to the official 
emission result of the emission-data engine. Note that where no 
deterioration factor applies,

[[Page 57396]]

references in this part to the deteriorated emission level mean the 
official emission result.
    Deterioration factor means the relationship between emissions at 
the end of useful life (or point of highest emissions if it occurs 
before the end of useful life) and emissions at the low-hour/low-
mileage test point, expressed in one of the following ways:
    (1) For multiplicative deterioration factors, the ratio of 
emissions at the end of useful life (or point of highest emissions) to 
emissions at the low-hour test point.
    (2) For additive deterioration factors, the difference between 
emissions at the end of useful life (or point of highest emissions) and 
emissions at the low-hour test point.
    Dual-fuel means relating to an engine designed for operation on two 
different types of fuel but not on a continuous mixture of those fuels.
    Emission control system means any device, system, or element of 
design that controls or reduces the emissions of regulated pollutants 
from an engine.
    Emission-data engine means an engine that is tested for 
certification. This includes engines tested to establish deterioration 
factors.
    Emission-related maintenance means maintenance that substantially 
affects emissions or is likely to substantially affect emission 
deterioration.
    Engine configuration means a unique combination of engine hardware 
and calibration (related to the emission standards) within an engine 
family. Engines within a single engine configuration differ only with 
respect to normal production variability or factors unrelated to 
compliance with emission standards.
    Engine family has the meaning given in Sec.  1036.230.
    Excluded means relating to engines that are not subject to some or 
all of the requirements of this part as follows:
    (1) An engine that has been determined not to be a heavy-duty 
engine is excluded from this part.
    (2) Certain heavy-duty engines are excluded from the requirements 
of this part under Sec.  1036.5.
    (3) Specific regulatory provisions of this part may exclude a 
heavy-duty engine generally subject to this part from one or more 
specific standards or requirements of this part.
    Exempted has the meaning given in 40 CFR 1068.30.
    Exhaust-gas recirculation means a technology that reduces emissions 
by routing exhaust gases that had been exhausted from the combustion 
chamber(s) back into the engine to be mixed with incoming air before or 
during combustion. The use of valve timing to increase the amount of 
residual exhaust gas in the combustion chamber(s) that is mixed with 
incoming air before or during combustion is not considered exhaust-gas 
recirculation for the purposes of this part.
    Family certification level (FCL) means a CO2 emission 
level declared by the manufacturer that is at or above emission test 
results for all emission-data engines. The FCL serves as the emission 
standard for the engine family with respect to certification testing if 
it is different than the otherwise applicable standard. The FCL must be 
expressed to the same number of decimal places as the emission standard 
it replaces.
    Family emission limit (FEL) means an emission level declared by the 
manufacturer to serve in place of an otherwise applicable emission 
standard (other than CO2 standards) under the ABT program in 
subpart H of this part. The FEL must be expressed to the same number of 
decimal places as the emission standard it replaces. The FEL serves as 
the emission standard for the engine family with respect to all 
required testing except certification testing for CO2. The 
CO2 FEL is equal to the CO2 FCL multiplied by 
1.03 and rounded to the same number of decimal places as the standard 
(e.g., the nearest whole g/hp-hr for the 2016 CO2 
standards).
    Flexible-fuel means relating to an engine designed for operation on 
any mixture of two or more different types of fuels.
    Fuel type means a general category of fuels such as diesel fuel, 
gasoline, or natural gas. There can be multiple grades within a single 
fuel type, such as premium gasoline, regular gasoline, or gasoline with 
10 percent ethanol.
    Good engineering judgment has the meaning given in 40 CFR 1068.30. 
See 40 CFR 1068.5 for the administrative process we use to evaluate 
good engineering judgment.
    Greenhouse gas pollutants and greenhouse gases means compounds 
regulated under this part based primarily on their impact on the 
climate. This includes CO2, CH4, and 
N2O.
    Gross vehicle weight rating (GVWR) means the value specified by the 
vehicle manufacturer as the maximum design loaded weight of a single 
vehicle, consistent with good engineering judgment.
    Heavy-duty engine means any engine which the engine manufacturer 
could reasonably expect to be used for motive power in a heavy-duty 
vehicle. For purposes of this definition in this part, the term 
``engine'' includes internal combustion engines and other devices that 
convert chemical fuel into motive power. For example, a fuel cell used 
in a heavy-duty vehicle is a heavy-duty engine.
    Heavy-duty vehicle means any motor vehicle above 8,500 pounds GVWR 
or that has a vehicle curb weight above 6,000 pounds or that has a 
basic vehicle frontal area greater than 45 square feet. Curb weight has 
the meaning given in 40 CFR 86.1803, consistent with the provisions of 
40 CFR 1037.140. Basic vehicle frontal area has the meaning given in 40 
CFR 86.1803.
    Hybrid engine or hybrid powertrain means an engine or powertrain 
that includes energy storage features other than a conventional battery 
system or conventional flywheel. Supplemental electrical batteries and 
hydraulic accumulators are examples of hybrid energy storage systems. 
Note that certain provisions in this part treat hybrid engines and 
powertrains intended for vehicles that include regenerative braking 
differently than those intended for vehicles that do not include 
regenerative braking.
    Hydrocarbon (HC) means the hydrocarbon group on which the emission 
standards are based for each fuel type. For alcohol-fueled engines, HC 
means nonmethane hydrocarbon equivalent (NMHCE). For all other engines, 
HC means nonmethane hydrocarbon (NMHC).
    Identification number means a unique specification (for example, a 
model number/serial number combination) that allows someone to 
distinguish a particular engine from other similar engines.
    Incomplete vehicle means a vehicle meeting the definition of 
incomplete vehicle in 40 CFR 1037.801 when it is first sold as a 
vehicle.
    Innovative technology means technology certified under Sec.  
1036.610.
    Liquefied petroleum gas (LPG) means a liquid hydrocarbon fuel that 
is stored under pressure and is composed primarily of nonmethane 
compounds that are gases at atmospheric conditions.
    Low-hour means relating to an engine that has stabilized emissions 
and represents the undeteriorated emission level. This would generally 
involve less than 125 hours of operation.
    Manufacture means the physical and engineering process of 
designing, constructing, and/or assembling a heavy-duty engine or a 
heavy-duty vehicle.
    Manufacturer has the meaning given in section 216(1) of the Act. In 
general, this term includes any person who manufactures an engine, 
vehicle, or

[[Page 57397]]

piece of equipment for sale in the United States or otherwise 
introduces a new engine into commerce in the United States. This 
includes importers who import engines or vehicles for resale.
    Medium-duty passenger vehicle has the meaning given in 40 CFR 
86.1803.
    Model year means the manufacturer's annual new model production 
period, except as restricted under this definition. It must include 
January 1 of the calendar year for which the model year is named, may 
not begin before January 2 of the previous calendar year, and it must 
end by December 31 of the named calendar year. Manufacturers may not 
adjust model years to circumvent or delay compliance with emission 
standards or to avoid the obligation to certify annually.
    Motor vehicle has the meaning given in 40 CFR 85.1703.
    Natural gas means a fuel whose primary constituent is methane.
    New motor vehicle engine means a motor vehicle engine meeting the 
criteria of either paragraph (1) or (2) of this definition.
    (1) A motor vehicle engine for which the ultimate purchaser has 
never received the equitable or legal title is a new motor vehicle 
engine. This kind of engine might commonly be thought of as ``brand 
new'' although a new motor vehicle engine may include previously used 
parts. Under this definition, the engine is new from the time it is 
produced until the ultimate purchaser receives the title or places it 
into service, whichever comes first.
    (2) An imported motor vehicle engine is a new motor vehicle engine 
if it was originally built on or after January 1, 1970.
    Noncompliant engine means an engine that was originally covered by 
a certificate of conformity, but is not in the certified configuration 
or otherwise does not comply with the conditions of the certificate.
    Nonconforming engine means an engine not covered by a certificate 
of conformity that would otherwise be subject to emission standards.
    Nonmethane hydrocarbons (NMHC) means the sum of all hydrocarbon 
species except methane, as measured according to 40 CFR part 1065.
    Official emission result means the measured emission rate for an 
emission-data engine on a given duty cycle before the application of 
any deterioration factor, but after the applicability of any required 
regeneration adjustment factors.
    Owner's manual means a document or collection of documents prepared 
by the engine or vehicle manufacturer for the owner or operator to 
describe appropriate engine maintenance, applicable warranties, and any 
other information related to operating or keeping the engine. The 
owner's manual is typically provided to the ultimate purchaser at the 
time of sale.
    Oxides of nitrogen has the meaning given in 40 CFR 1065.1001.
    Percent has the meaning given in 40 CFR 1065.1001. Note that this 
means percentages identified in this part are assumed to be infinitely 
precise without regard to the number of significant figures. For 
example, one percent of 1,493 is 14.93.
    Petroleum means gasoline or diesel fuel or other fuels normally 
derived from crude oil. This does not include methane or LPG.
    Placed into service means put into initial use for its intended 
purpose.
    Primary intended service class has the meaning given in Sec.  
1036.140.
    Rated power has the meaning given in 40 CFR part 86.
    Rechargeable Energy Storage System (RESS) means the component(s) of 
a hybrid engine or vehicle that store recovered energy for later use, 
such as the battery system in an electric hybrid vehicle.
    Revoke has the meaning given in 40 CFR 1068.30.
    Round has the meaning given in 40 CFR 1065.1001.
    Scheduled maintenance means adjusting, repairing, removing, 
disassembling, cleaning, or replacing components or systems 
periodically to keep a part or system from failing, malfunctioning, or 
wearing prematurely. It also may mean actions you expect are necessary 
to correct an overt indication of failure or malfunction for which 
periodic maintenance is not appropriate.
    Small manufacturer means a manufacturer meeting the criteria 
specified in 13 CFR 121.201. For manufacturers owned by a parent 
company, the employee and revenue limits apply to the total number of 
employees and total revenue of the parent company and all its 
subsidiaries.
    Spark-ignition means relating to a gasoline-fueled engine or any 
other type of engine with a spark plug (or other sparking device) and 
with operating characteristics significantly similar to the theoretical 
Otto combustion cycle. Spark-ignition engines usually use a throttle to 
regulate intake air flow to control power during normal operation.
    Steady-state has the meaning given in 40 CFR 1065.1001.
    Suspend has the meaning given in 40 CFR 1068.30.
    Test engine means an engine in a test sample.
    Test sample means the collection of engines selected from the 
population of an engine family for emission testing. This may include 
testing for certification, production-line testing, or in-use testing.
    Tractor means a vehicle meeting the definition of ``tractor'' in 40 
CFR 1037.801, but not classified as a ``vocational tractor'' under 40 
CFR 1037.630, or relating to such a vehicle.
    Tractor engine means an engine certified for use in tractors. Where 
an engine family is certified for use in both tractors and vocational 
vehicles, ``tractor engine'' means an engine that the engine 
manufacturer reasonably believes will be (or has been) installed in a 
tractor. Note that the provisions of this part may require a 
manufacturer to document how it determines that an engine is a tractor 
engine.
    Ultimate purchaser means, with respect to any new engine or 
vehicle, the first person who in good faith purchases such new engine 
or vehicle for purposes other than resale.
    United States has the meaning given in 40 CFR 1068.30.
    Upcoming model year means for an engine family the model year after 
the one currently in production.
    U.S.-directed production volume means the number of engines, 
subject to the requirements of this part, produced by a manufacturer 
for which the manufacturer has a reasonable assurance that sale was or 
will be made to ultimate purchasers in the United States. This does not 
include engines certified to state emission standards that are 
different than the emission standards in this part.
    Vehicle has the meaning given in 40 CFR 1037.801.
    Vocational engine means an engine certified for use in vocational 
vehicles. Where an engine family is certified for use in both tractors 
and vocational vehicles, ``vocational engine'' means an engine that the 
engine manufacturer reasonably believes will be (or has been) installed 
in a vocational vehicle. Note that the provisions of this part may 
require a manufacturer to document how it determines that an engine is 
a vocational engine.
    Vocational vehicle means a vehicle meeting the definition of 
``vocational'' vehicle in 40 CFR 1037.801.
    Void has the meaning given in 40 CFR 1068.30.
    We (us, our) means the Administrator of the Environmental 
Protection Agency and any authorized representatives.

[[Page 57398]]

Sec.  1036.805  Symbols, acronyms, and abbreviations.

    The following symbols, acronyms, and abbreviations apply to this 
part:
    ABT averaging, banking, and trading.
    AECD auxiliary emission control device.
    ASTM American Society for Testing and Materials.
    BTU British thermal units.
    CFR Code of Federal Regulations.
    CH4 methane.
    CO carbon monoxide.
    CO2 carbon dioxide.
    DF deterioration factor.
    DOT Department of Transportation.
    E85 gasoline blend including nominally 85 percent ethanol.
    EPA Environmental Protection Agency.
    FCL Family Certification Level.
    FEL Family Emission Limit.
    g/hp-hr grams per brake horsepower-hour.
    GVWR gross vehicle weight rating.
    HC hydrocarbon.
    kg kilogram.
    kgC kilogram carbon.
    kW kilowatts.
    lb pound.
    lbC pound carbon.
    LPG liquefied petroleum gas.
    Mg megagrams (10 \6\ grams, or one metric ton).
    MJ megajoules.
    N2O nitrous oxide.
    NARA National Archives and Records Administration.
    NHTSA National Highway Traffic Safety Administration.
    NOx oxides of nitrogen (NO and NO2).
    NTE not-to-exceed.
    PM particulate matter.
    RESS rechargeable energy storage system.
    RPM revolutions per minute.
    SET Supplemental Emission Test (see 40 CFR 86.1362).
    U.S. United States.
    U.S.C. United States Code.

Sec.  1036.810  Incorporation by reference.

    (a) Certain material is incorporated by reference into this part 
with the approval of the Director of the Federal Register under 5 
U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other than that 
specified in this section, the Environmental Protection Agency must 
publish a notice of the change in the Federal Register and the material 
must be available to the public. All approved material is available for 
inspection at U.S. EPA, Air and Radiation Docket and Information 
Center, 1301 Constitution Ave., NW., Room B102, EPA West Building, 
Washington, DC 20460, (202) 202-1744, and is available from the sources 
listed below. It is also available for inspection at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to 
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
    (b) American Society for Testing and Materials, 100 Barr Harbor 
Drive, P.O. Box C700, West Conshohocken, PA, 19428-2959, (610) 832-
9585, http://www.astm.org/.
    (1) ASTM D 240-09 Standard Test Method for Heat of Combustion of 
Liquid Hydrocarbon Fuels by Bomb Calorimeter, approved July 1, 2009, 
IBR approved for Sec.  1036.530(b).
    (2) ASTM D4809-09a Standard Test Method for Heat of Combustion of 
Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method), 
approved September 1, 2009, IBR approved for Sec.  1036.530(b).
    (3) ASTM D5291-10 Standard Test Methods for Instrumental 
Determination of Carbon, Hydrogen, and Nitrogen in Petroleum Products 
and Lubricants, approved May 1, 2010, IBR approved for Sec.  
1036.530(b).

Sec.  1036.815  Confidential information.

    The provisions of 40 CFR 1068.10 apply for information you consider 
confidential.

Sec.  1036.820  Requesting a hearing.

    (a) You may request a hearing under certain circumstances, as 
described elsewhere in this part. To do this, you must file a written 
request, including a description of your objection and any supporting 
data, within 30 days after we make a decision.
    (b) For a hearing you request under the provisions of this part, we 
will approve your request if we find that your request raises a 
substantial factual issue.
    (c) If we agree to hold a hearing, we will use the procedures 
specified in 40 CFR part 1068, subpart G.

Sec.  1036.825  Reporting and recordkeeping requirements.

    (a) This part includes various requirements to submit and record 
data or other information. Unless we specify otherwise, store required 
records in any format and on any media and keep them readily available 
for eight years after you send an associated application for 
certification, or eight years after you generate the data if they do 
not support an application for certification. You may not rely on 
anyone else to meet recordkeeping requirements on your behalf unless we 
specifically authorize it. We may review these records at any time. You 
must promptly send us organized, written records in English if we ask 
for them. We may require you to submit written records in an electronic 
format.
    (b) The regulations in Sec.  1036.255 and 40 CFR 1068.25 and 
1068.101 describe your obligation to report truthful and complete 
information. This includes information not related to certification. 
Failing to properly report information and keep the records we specify 
violates 40 CFR 1068.101(a)(2), which may involve civil or criminal 
penalties.
    (c) Send all reports and requests for approval to the Designated 
Compliance Officer (see Sec.  1036.801).
    (d) Any written information we require you to send to or receive 
from another company is deemed to be a required record under this 
section. Such records are also deemed to be submissions to EPA. Keep 
these records for eight years unless the regulations specify a 
different period. We may require you to send us these records whether 
or not you are a certificate holder.
    (e) Under the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the 
Office of Management and Budget approves the reporting and 
recordkeeping specified in the applicable regulations. The following 
items illustrate the kind of reporting and recordkeeping we require for 
engines and equipment regulated under this part:
    (1) We specify the following requirements related to engine 
certification in this part 1036:
    (i) In Sec.  1036.135 we require engine manufacturers to keep 
certain records related to duplicate labels sent to equipment 
manufacturers.
    (ii) In subpart C of this part we identify a wide range of 
information required to certify engines.
    (iii) In subpart G of this part we identify several reporting and 
recordkeeping items for making demonstrations and getting approval 
related to various special compliance provisions.
    (iv) In Sec. Sec.  1036.725, 1036.730, and 1036.735 we specify 
certain records related to averaging, banking, and trading.
    (2) We specify the following requirements related to testing in 40 
CFR part 1066:
    (i) In 40 CFR 1066.2 we give an overview of principles for 
reporting information.
    (ii) [Reserved]

0
34. A new part 1037 is added to subchapter U to read as follows:

[[Page 57399]]

PART 1037--CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES

Subpart A--Overview and Applicability
Sec.
1037.1 Applicability
1037.5 Excluded vehicles.
1037.10 How is this part organized?
1037.15 Do any other regulation parts apply to me?
1037.30 Submission of information.
Subpart B--Emission Standards and Related Requirements
1037.101 Overview of emission standards for heavy-duty vehicles.
1037.102 Exhaust emission standards for NOX, HC, PM, and 
CO.
1037.104 Exhaust emission standards for CO2, 
CH4, and N2O for heavy-duty vehicles at or 
below 14,000 pounds GVWR.
1037.105 Exhaust emission standards for CO2 for 
vocational vehicles.
1037.106 Exhaust emission standards for CO2 for tractors 
above 26,000 pounds GVWR.
1037.115 Other requirements.
1037.120 Emission-related warranty requirements.
1037.125 Maintenance instructions and allowable maintenance.
1037.135 Labeling.
1037.140 Curb weight and roof height.
1037.150 Interim provisions.
Subpart C--Certifying Vehicle families
1037.201 General requirements for obtaining a certificate of 
conformity.
1037.205 What must I include in my application?
1037.210 Preliminary approval before certification.
1037.220 Amending maintenance instructions.
1037.225 Amending applications for certification.
1037.230 Vehicle families, sub-families, and configurations.
1037.241 Demonstrating compliance with exhaust emission standards 
for greenhouse gas pollutants.
1037.250 Reporting and recordkeeping.
1037.255 What decisions may EPA make regarding my certificate of 
conformity?
Subpart D--[Reserved]
Subpart E--In-Use Testing
1037.401 General provisions.
Subpart F--Test and Modeling Procedures
1037.501 General testing and modeling provisions.
1037.510 Duty-cycle exhaust testing.
1037.520 Modeling CO2 emissions to show compliance.
1037.521 Aerodynamic measurements.
1037.525 Special procedures for testing hybrid vehicles with power 
take-off.
1037.550 Special procedures for testing post-transmission hybrid 
systems.
Subpart G--Special Compliance Provisions
1037.601 What compliance provisions apply to these vehicles?
1037.610 Vehicles with innovative technologies.
1037.615 Hybrid vehicles and other advanced technologies.
1037.620 Shipment of incomplete vehicles to secondary vehicle 
manufacturers.
1037.630 Special purpose tractors.
1037.631 Exemption for vocational vehicles intended for off-road 
use.
1037.640 Variable vehicle speed limiters.
1037.645 In-use compliance with family emission limits (FELs).
1037.650 Tire manufacturers.
1037.655 Post-useful life vehicle modifications.
1037.660 Automatic engine shutdown systems.
Subpart H--Averaging, Banking, and Trading for Certification
1037.701 General provisions.
1037.705 Generating and calculating emission credits.
1037.710 Averaging.
1037.715 Banking.
1037.720 Trading.
1037.725 What must I include in my application for certification?
1037.730 ABT reports.
1037.735 Recordkeeping.
1037.740 Restrictions for using emission credits.
1037.745 End-of-year CO2 credit deficits.
1037.750 What can happen if I do not comply with the provisions of 
this subpart?
1037.755 Information provided to the Department of Transportation.
Subpart I--Definitions and Other Reference Information
1037.801 Definitions.
1037.805 Symbols, acronyms, and abbreviations.
1037.810 Incorporation by reference.
1037.815 Confidential information.
1037.820 Requesting a hearing.
1037.825 Reporting and recordkeeping requirements.
Appendix I to Part 1037--Heavy-duty Transient Chassis Test Cycle
Appendix II to Part 1037--Power Take-Off Test Cycle
Appendix III to Part 1037--Emission Control Identifiers

    Authority: 42 U.S.C. 7401--7671q.

Subpart A--Overview and Applicability

Sec.  1037.1  Applicability

    This part contains standards and other regulations applicable to 
the emission of the air pollutant defined as the aggregate group of six 
greenhouse gases: carbon dioxide, nitrous oxide, methane, 
hydrofluorocarbons, perflurocarbons, and sulfur hexafluoride. The 
regulations in this part 1037 apply for all new heavy-duty vehicles, 
except as provided in Sec.  1037.5. This includes electric vehicles and 
vehicles fueled by conventional and alternative fuels.

Sec.  1037.5  Excluded vehicles.

    Except for the definitions specified in Sec.  1037.801, this part 
does not apply to the following vehicles:
    (a) Vehicles not meeting the definition of ``motor vehicle''.
    (b) Vehicles excluded from the definition of ``heavy-duty vehicle'' 
in Sec.  1037.801 because of vehicle weight, weight rating, and frontal 
area (such as light-duty vehicles and light-duty trucks).
    (c) Medium-duty passenger vehicles.
    (d) Vehicles produced in model years before 2014, unless they are 
certified under Sec.  1037.150.
    (e) Vehicles subject to the light-duty greenhouse gas standards of 
40 CFR part 86. See 40 CFR 86.1818 for greenhouse gas standards that 
apply for these vehicles. An example of such a vehicle would be a 
vehicle meeting the definition of ``heavy-duty vehicle'' in Sec.  
1037.801 and 40 CFR 86.1803, but also meeting the definition of ``light 
truck'' in 40 CFR 86.1818-12(b)(2).

Sec.  1037.10  How is this part organized?

    This part 1037 is divided into subparts as described in this 
section. Note that only subparts A, B, and I of this part apply for 
vehicles subject to the standards of Sec.  1037.104, as described in 
that section.
    (a) Subpart A of this part defines the applicability of part 1037 
and gives an overview of regulatory requirements.
    (b) Subpart B of this part describes the emission standards and 
other requirements that must be met to certify vehicles under this 
part. Note that Sec.  1037.150 discusses certain interim requirements 
and compliance provisions that apply only for a limited time.
    (c) Subpart C of this part describes how to apply for a certificate 
of conformity for vehicles subject to the standards of Sec.  1037.105 
or Sec.  1037.106.
    (d) [Reserved]
    (e) Subpart E of this part addresses testing of in-use vehicles.
    (f) Subpart F of this part describes how to test your vehicles and 
perform emission modeling (including references to other parts of the 
Code of Federal Regulations) for vehicles subject to the standards of 
Sec.  1037.105 or Sec.  1037.106.
    (g) Subpart G of this part and 40 CFR part 1068 describe 
requirements, prohibitions, and other provisions that apply to 
manufacturers, owners, operators, rebuilders, and all others. Section 
1037.601 describes how 40 CFR part 1068 applies for heavy-duty 
vehicles.
    (h) Subpart H of this part describes how you may generate and use 
emission

[[Page 57400]]

credits to certify vehicles that are subject to the standards of Sec.  
1037.105 or Sec.  1037.106.
    (i) Subpart I of this part contains definitions and other reference 
information.

Sec.  1037.15  Do any other regulation parts apply to me?

    (a) Parts 1065 and 1066 of this chapter describe procedures and 
equipment specifications for testing engines and vehicles to measure 
exhaust emissions. Subpart F of this part 1037 describes how to apply 
the provisions of part 1065 and part 1066 of this chapter to determine 
whether vehicles meet the exhaust emission standards in this part.
    (b) As described in Sec.  1037.601, certain requirements and 
prohibitions of part 1068 of this chapter apply to everyone, including 
anyone who manufactures, imports, installs, owns, operates, or rebuilds 
any of the vehicles subject to this part 1037. Part 1068 of this 
chapter describes general provisions that apply broadly, but do not 
necessarily apply for all vehicles or all persons. The issues addressed 
by these provisions include these seven areas:
    (1) Prohibited acts and penalties for manufacturers and others.
    (2) Rebuilding and other aftermarket changes.
    (3) Exclusions and exemptions for certain vehicles.
    (4) Importing vehicles.
    (5) Selective enforcement audits of your production.
    (6) Recall.
    (7) Procedures for hearings.
    (c) Part 86 of this chapter applies for certain vehicles as 
specified in this part. For example, the test procedures and most of 
part 86, subpart S, applies for vehicles subject to Sec.  1037.104.
    (d) Other parts of this chapter apply if referenced in this part.

Sec.  1037.30  Submission of information.

    Send all reports and requests for approval to the Designated 
Compliance Officer (see Sec.  1037.801). See Sec.  1037.825 for 
additional reporting and recordkeeping provisions.

Subpart B--Emission Standards and Related Requirements

Sec.  1037.101  Overview of emission standards for heavy-duty vehicles.

    (a) This part specifies emission standards for certain vehicles and 
for certain pollutants. It also summarizes other standards that apply 
under 40 CFR part 86. This part contains standards and other 
regulations applicable to the emission of the air pollutant defined as 
the aggregate group of six greenhouse gases: carbon dioxide, nitrous 
oxide, methane, hydrofluorocarbons, perflurocarbons, and sulfur 
hexafluoride.
    (b) The regulated emissions are addressed in four groups:
    (1) Exhaust emissions of NOX, HC, PM, and CO. These 
pollutants are sometimes described collectively as ``criteria 
pollutants'' because they are either criteria pollutants under the 
Clean Air Act or precursors to the criteria pollutant ozone. These 
pollutants are also sometimes described collectively as ``non-
greenhouse gas pollutants'', although they do not necessarily have 
negligible global warming potential. As described in Sec.  1037.102, 
standards for these pollutants are provided in 40 CFR part 86.
    (2) Exhaust emissions of CO2, CH4, and 
N2O. These pollutants are described collectively in this 
part as ``greenhouse gas pollutants'' because they are regulated 
primarily based on their impact on the climate. These standards are 
provided in Sec. Sec.  1037.104 through 1037.106.
    (3) Hydrofluorocarbons. These pollutants are also ``greenhouse gas 
pollutants'' but are treated separately from exhaust greenhouse gas 
pollutants listed in paragraph (b)(2) of this section. These standards 
are provided in Sec.  1037.115.
    (4) Fuel evaporative emissions. These requirements are described in 
40 CFR part 86.
    (c) The regulated heavy-duty vehicles are addressed in different 
groups as follows:
    (1) For criteria pollutants, vehicles are regulated based on gross 
vehicle weight rating (GVWR), whether they are considered ``spark-
ignition'' or ``compression-ignition,'' and whether they are first sold 
as complete or incomplete vehicles. These groupings apply as described 
in 40 CFR part 86.
    (2) For greenhouse gas pollutants, vehicles are regulated in the 
following groups:
    (i) Complete and certain incomplete vehicles at or below 14,000 
pounds GVWR (see Sec.  1037.104 for further specification). Certain 
provisions of 40 CFR part 86 apply for these vehicles; see Sec.  
1037.104(h) for a list of provisions in this part 1037 that also apply 
for these vehicles. These provisions may also be optionally applied to 
certain other vehicles, as described in Sec.  1037.104.
    (ii) Tractors above 26,000 pounds GVWR.
    (iii) All other vehicles subject to standards under this part. 
These other vehicles are referred to as ``vocational'' vehicles.

Sec.  1037.102  Exhaust emission standards for NOX, HC, PM, and CO.

    See 40 CFR part 86 for the exhaust emission standards for 
NOX, HC, PM, and CO that apply for heavy-duty vehicles.

Sec.  1037.104  Exhaust emission standards for CO2, 
CH4, and N2O for heavy-duty vehicles at or below 
14,000 pounds GVWR.

    This section applies for heavy-duty vehicles at or below 14,000 
pounds GVWR. See paragraph (f) of this section and Sec.  1037.150 of 
this section for provisions excluding certain vehicles from this 
section, and allowing other vehicles to be certified under this 
section.
    (a) Fleet-average CO2 emission standards. Fleet-average 
CO2 emission standards apply for each manufacturer as 
follows:
    (1) Calculate a work factor, WF, for each vehicle subconfiguration 
(or group of subconfigurations allowed under paragraph (a)(4) of this 
section), rounded to the nearest pound, using the following equation:

WF = 0.75 x (GVWR - Curb Weight + xwd) + 0.25 x (GCWR - GVWR)
Where:

xwd = 500 pounds if the vehicle has four-wheel drive or all-wheel 
drive; xwd = 0 pounds for all other vehicles.

    (2) Using the appropriate work factor, calculate a target value for 
each vehicle subconfiguration (or group of subconfigurations allowed 
under paragraph (a)(4) of this section) you produce using one of the 
following equations, rounding to the nearest 0.1 g/mile:
    (i) For spark-ignition vehicles: CO2 Target (g/mile) = 
0.0440 x WF + 339
    (ii) For compression-ignition vehicles and vehicles that operate 
without engines (such as electric vehicles and fuel cell vehicles): 
CO2 Target (g/mile) = 0.0416 x WF + 320
    (3) Calculate a production-weighted average of the target values 
and round it to the nearest 0.1 g/mile. This is your fleet-average 
standard. All vehicles subject to the standards of this section form a 
single averaging set. Use the following equation to calculate your 
fleet-average standard from the target value for each vehicle 
subconfiguration (Targeti) and U.S.-directed production 
volume of each vehicle subconfiguration for the given model year 
(Volumei):

[[Page 57401]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.008

    (4) You may group subconfigurations within a configuration together 
for purposes of calculating your fleet-average standard as follows:
    (i) You may group together subconfigurations that have the same 
equivalent test weight (ETW), GVWR, and GCWR. Calculate your work 
factor and target value assuming a curb weight equal to two times ETW 
minus GVWR.
    (ii) You may group together other subconfigurations if you use the 
lowest target value calculated for any of the subconfigurations.
    (b) Production and in-use CO2 standards. Each vehicle you produce 
that is subject to the standards of this section has an ``in-use'' 
CO2 standard that is calculated from your test result and 
that applies for selective enforcement audits and in-use testing. This 
in-use CO2 standard for each vehicle is equal to the 
applicable deteriorated emission level multiplied by 1.10 and rounded 
to the nearest 0.1 g/mile.
    (c) N2O and CH4 standards. Except as allowed under this paragraph 
(c), all vehicles subject to the standards of this section must comply 
with an N2O standard of 0.05 g/mile and a CH4 
standard of 0.05 g/mile. You may specify CH4 and/or 
N2O alternate standards using CO2 emission 
credits instead of these otherwise applicable emission standards for 
one or more test groups, consistent with the provisions of 40 CFR 
86.1818. To do this, calculate the CH4 and/or N2O 
emission credits needed (negative credits) using the equation in this 
paragraph (c) based on the FEL(s) you specify for your vehicles during 
certification. You must adjust the calculated emissions by the global 
warming potential (GWP): GWP equals 25 for CH4 and 298 for 
N2O. This means you must use 25 Mg of positive 
CO2 credits to offset 1 Mg of negative CH4 
credits and 298 Mg of positive CO2 credits to offset 1 Mg of 
negative N2O credits. Note that 40 CFR 86.1818-12(f) does 
not apply for vehicles subject to the standards of this section. 
Calculate credits using the following equation:

CO2 Credits Needed (Mg) = [(FEL--Std) x (U.S.-directed 
production volume) x (Useful Life)] x (GWP) / 1,000,000

    (d) Compliance provisions. Except as specified in this paragraph 
(d) or elsewhere in this section, the provisions of 40 CFR part 86, 
describing compliance with the greenhouse gas standards of 40 CFR part 
86, subpart S, apply with respect to the standards of paragraphs (a) 
through (c) of this section.
    (1) The CO2 standards of this section apply with respect 
to CO2 emissions, not with respect to carbon-related exhaust 
emissions (CREE).
    (2) Vehicles subject to the standards of this section are included 
in a single greenhouse gas averaging set separate from any averaging 
sets otherwise included in 40 CFR part 86.
    (3) Special credit and incentive provisions related to flexible 
fuel vehicles and air conditioning in 40 CFR part 86 do not apply for 
vehicles subject to the standards of this section.
    (4) The CO2, N2O, and CH4 
standards apply for a weighted average of the city (55%) and highway 
(45%) test cycle results as specified for light-duty vehicles in 40 CFR 
part 86, subpart S. Note that this differs from the way the criteria 
pollutant standards apply for heavy-duty vehicles.
    (5) Apply an additive deterioration factor of zero to measured 
CO2 emissions unless good engineering judgment indicates 
that emissions are likely to deteriorate in use. Use good engineering 
judgment to develop separate deterioration factors for N2O 
and CH4.
    (6) Credits are calculated using the useful life value (in miles) 
in place of the ``vehicle lifetime miles'' specified in 40 CFR part 86, 
subpart S.
    (7) Credits generated from hybrid vehicles with regenerative 
braking or from vehicles with other advanced technologies may be used 
to show compliance with any standards of this part or 40 CFR part 1036, 
subject to the service class restrictions in Sec.  1037.740. Include 
these vehicles in a separate fleet-average calculation (and exclude 
them from your conventional fleet-average calculation). You must first 
apply these advanced technology vehicle credits to any deficits for 
other vehicles in the averaging set before applying them to other 
averaging sets.
    (8) The provisions of 40 CFR 86.1818 do not apply.
    (9) Calculate your fleet-average emission rate consistent with good 
engineering judgment and the provisions of 40 CFR 86.1865. The 
following additional provisions apply:
    (i) Unless we approve a lower number, you must test at least ten 
subconfigurations. If you produce more than 100 subconfigurations in a 
given model year, you must test at least ten percent of your 
subconfigurations. For purposes of this paragraph (d)(9)(i), count 
carryover tests, but do not include analytically derived CO2 
emission rates, data substitutions, or other untested allowances. We 
may approve a lower number of tests for manufacturers that have limited 
product offerings, or low sales volumes. Note that good engineering 
judgment and other provisions of this part may require you to test more 
subconfigurations than these minimum values.
    (ii) The provisions of paragraph (g) of this section specify how 
you may use analytically derived CO2 emission rates.
    (iii) At least 90 percent of final production volume at the 
configuration level must be represented by test data (real, data 
substituted, or analytical).
    (10) For dual fuel, multi-fuel, and flexible fuel vehicles, perform 
exhaust testing on each fuel type (for example, gasoline and E85).
    (i) For your fleet-average calculations, use either the 
conventional-fueled CO2 emission rate or a weighted average 
of your emission results as specified in 40 CFR 600.510-12(k) for 
light-duty trucks.
    (ii) If you certify to an alternate standard for N2O or 
CH4 emissions, you may not exceed the alternate standard 
when tested on either fuel.
    (11) Test your vehicles with an equivalent test weight based on its 
Adjusted Loaded Vehicle Weight (ALVW). Determine equivalent test weight 
from the ALVW as specified in 40 CFR 86.129, except that you may round 
values to the nearest 500 pound increment for ALVW above 14,000 
pounds).
    (12) The following definitions apply for purposes of this section:
    (i) Configuration means a subclassification within a test group 
which is based on engine code, transmission type and gear ratios, final 
drive ratio, and other parameters which we designate. Note that this 
differs from the definition in 40 CFR 86.1803 because it excludes 
inertia weight class as a criterion.
    (ii) Subconfiguration means a unique combination within a vehicle 
configuration (as defined in this paragraph (d)(12)) of equivalent test 
weight, road-load horsepower, and any other operational characteristics 
or parameters that we determine may significantly affect CO2 
emissions within a vehicle configuration.

[[Page 57402]]

    (iii) The terms ``complete vehicle'' and ``incomplete vehicle'' 
have the meanings given for ``complete heavy-duty vehicle'' and 
``incomplete heavy-duty vehicle'' in 40 CFR 86.1803.
    (13) This paragraph (d)(13) applies for CO2 reductions 
resulting from technologies that were not in common use before 2010 
that are not reflected in the specified test procedures. We may allow 
you to generate emission credits consistent with the provisions of 40 
CFR 86.1866-12(d). You do not need to provide justification for not 
using the 5-cycle methodology option.
    (14) You must submit pre-model year reports before you submit your 
applications for certification for a given model year. Unless we 
specify otherwise, include the information specified for pre-model year 
reports in 49 CFR 535.8.
    (e) Useful life. Your vehicles must meet the exhaust emission 
standards of this section throughout their full useful life, expressed 
in service miles or calendar years, whichever comes first. The useful 
life values for the standards of this section are those that apply for 
criteria pollutants under 40 CFR part 86.
    (f) Exclusion of vehicles not certified as complete vehicles. The 
standards of this section apply for each vehicle that is chassis-
certified with respect to criteria pollutants under 40 CFR part 86, 
subpart S. The standards of this section do not apply for other 
vehicles, except as noted in Sec.  1037.150. Note that vehicles 
excluded under this paragraph (f) are not considered to be ``subject to 
the standards of this section.'' The vehicle standards and requirements 
of Sec.  1037.105 apply for the excluded vehicles. The GHG standards of 
40 CFR part 1036 also apply for engines used in these excluded 
vehicles. If you are not the engine manufacturer, you must notify the 
engine manufacturer that its engines are subject to 40 CFR part 1036 
because you intend to use their engines in your excluded vehicles.
    (g) Analytically derived CO2 emission rates (ADCs). This 
paragraph (g) describes an allowance to use estimated (i.e., 
analytically derived) CO2 emission rates based on baseline 
test data instead of measured emission rates for calculating fleet-
average emissions. Note that these ADCs are similar to ADFEs used for 
light-duty vehicles. Note also that F terms used in this paragraph (g) 
represent coefficients from the following road load equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.009

    (1) Except as specified in paragraph (g)(2) of this section, use 
the following equation to calculate the ADC of a new vehicle from road 
load force coefficients (F0, F1, F2), axle ratio, and test weight:
[GRAPHIC] [TIFF OMITTED] TR15SE11.010

Where:

ADC = Analytically derived combined city/highway CO2 
emission rate (g/mile) for a new vehicle.
CO2base = Combined city/highway CO2 emission 
rate (g/mile) of a baseline vehicle.
[Delta]F0 = F0 of the new vehicle--F0 of the baseline vehicle.
[Delta]F1 = F1 of the new vehicle--F1 of the baseline vehicle.
[Delta]F2 = F2 of the new vehicle--F2 of the baseline vehicle.
[Delta]AR = Axle ratio of the new vehicle--axle ratio of the 
baseline vehicle.

[Delta]ETW = ETW of the new vehicle--ETW of the baseline vehicle.

    (2) The purpose of this section is to accurately estimate 
CO2 emission rates. You must apply the provisions of this 
section consistent with good engineering judgment. For example, do not 
use the equation in paragraph (g)(1) of this section where good 
engineering judgment indicates that it will not accurately estimate 
emissions. You may ask us to approve alternate equations that allow you 
to estimate emissions more accurately.
    (3) You may select, without our prior approval, baseline test data 
that meet all the following criteria:
    (i) Vehicles considered for selection for the baseline test must 
comply with all applicable emission standards in the model year 
associated with the ADC.
    (ii) You must include in the pool of tests which will be considered 
for baseline selection all official tests of the same or equivalent 
basic engine, transmission class, engine code, transmission code, 
engine horsepower, dynamometer drive wheels, and compression ratio as 
the ADC subconfiguration. Do not include tests in which emissions 
exceed any applicable standards.
    (iii) Where necessary to minimize the CO2 adjustment, 
you may supplement the pool with tests associated with worst-case 
engine or transmission codes and carryover or carry-across engine 
families. If you do, all the data that qualify for inclusion using the 
elected worst-case substitution (or carryover or carry-across) must be 
included in the pool as supplemental data (i.e., individual test 
vehicles may not be selected for inclusion). You must also include the 
supplemental data in all subsequent pools, where applicable.
    (iv) Tests previously used during the subject model year as 
baseline tests in ten other ADC subconfigurations must be eliminated 
from the pool. (v) Select the tested subconfiguration with the smallest 
absolute difference between the ADC and the test CO2 
emission rate for combined emissions. Use this as the baseline test for 
the target ADC subconfiguration.
    (4) You may ask us to allow you use baseline test data not fully 
meeting the provisions of paragraph (g)(3) of this section.
    (5) Calculate the ADC rounded to the nearest 0.1 g/mile. The 
downward adjustment of ADC from the baseline is limited to ADC values 
20 percent below the baseline emission rate (i.e., baseline emission 
rate x 0.80). The upward adjustment is not limited.
    (6) You may not submit an ADC if an actual test has been run on the 
target subconfiguration during the certification process or on a 
development vehicle that is eligible to be declared as an emission-data 
vehicle.
    (7) No more than 40 percent of the subconfigurations tested in your 
final CO2 submission may be represented by ADCs.
    (8) You must retain for five years the pool of tests, the vehicle 
description and tests chosen as the baseline and the basis for its 
selection, the target ADC subconfiguration, and the calculated emission 
rates. We may ask to see these records at any time.
    (9) We may perform or order a confirmatory test of any 
subconfiguration covered by an ADC.

[[Page 57403]]

    (10) Where we determine that you did not fully comply with the 
provisions of this paragraph (g), we may rescind the use of ADC data, 
require generation of actual test data, and require recalculation of 
your fleet-average emission rate.
    (h) Applicability of part 1037 provisions. Except as specified in 
this section, the requirements of this part do not apply to vehicles 
certified to the standards of this section. The following provisions 
are the only provisions of this part that apply to vehicles certified 
under this section:
    (1) The provisions of this section.
    (2) [Reserved]
    (3) The air conditioning standards in Sec.  1037.115.
    (4) The interim provisions of Sec.  1037.150(a), (b), (c), (e)-(i), 
(l), and (m).
    (5) The definitions of Sec.  1037.801, to the extent such terms are 
used relative to vehicles subject to standards under this section.

Sec.  1037.105  Exhaust emission standards for CO2 for 
vocational vehicles.

    (a) The standards of this section apply for the following vehicles:
    (1) Vehicles above 14,000 pounds GVWR and at or below 26,000 pounds 
GVWR, but not certified to the vehicle standards Sec.  1037.104.
    (2) Vehicles above 26,000 pounds GVWR that are not tractors.
    (3) Vocational tractors.
    (4) Vehicles at or below 14,000 pounds GVWR that are excluded from 
the standards in Sec.  1037.104 under Sec.  1037.104 (f) or use engines 
certified under Sec.  1037.150(m).
    (b) The CO2 standards of this section are given in Table 
1 to this section. The provisions of Sec.  1037.241 specify how to 
comply with these standards.

    Table 1 to Sec.   1037.105--CO2 Standards for Vocational Vehicles
------------------------------------------------------------------------
                                           CO2 standard
                                           (g/ton-mile)    CO2 standard
             GVWR  (pounds)                  for model     (g/ton-mile)
                                            years 2014-   for model year
                                               2016       2017 and later
------------------------------------------------------------------------
GVWR 4 or N2O standards apply under this 
section. See 40 CFR part 1036 for CH4 or N2O 
standards that apply to engines used in these vehicles.
    (d) You may generate or use emission credits under the ABT program 
as described in subpart H of this part. This requires that you specify 
a Family Emission Limit (FEL) for CO2 for each vehicle 
subfamily. The FEL may not be less than the result of emission modeling 
from Sec.  1037.520. These FELs serve as the emission standards for the 
vehicle subfamily instead of the standards specified in paragraph (b) 
of this section.
    (e) Your vehicles must meet the exhaust emission standards of this 
section throughout their full useful life, expressed in service miles 
or calendar years, whichever comes first. The following useful life 
values apply for the standards of this section:
    (1) 110,000 miles or 10 years, whichever comes first, for vehicles 
at or below 19,500 pounds GVWR.
    (2) 185,000 miles or 10 years, whichever comes first, for vehicles 
above 19,500 pounds GVWR and at or below 33,000 pounds GVWR.
    (3) 435,000 miles or 10 years, whichever comes first, for vehicles 
above 33,000 pounds GVWR.
    (f) See Sec.  1037.631 for provisions that exempt certain vehicles 
used in off-road operation from the standards of this section.
    (g) You may optionally certify a vocational vehicle to the 
standards and useful life applicable to a higher vehicle service class 
(such as medium heavy-duty instead of light heavy-duty), provided you 
do not generate credits with the vehicle. If you include smaller 
vehicles in a credit-generating subfamily (with an FEL below the 
standard), exclude its production volume from the credit calculation.

Sec.  1037.106  Exhaust emission standards for CO2 for 
tractors above 26,000 pounds GVWR.

    (a) The CO2 standards of this section apply for tractors 
above 26,000 pounds GVWR. Note that the standards of this section do 
not apply for vehicles classified as ``vocational tractors'' under 
Sec.  1037.630,
    (b) The CO2 standards for tractors above 26,000 pounds 
GVWR are given in Table 1 to this section. The provisions of Sec.  
1037.241 specify how to comply with these standards.

                 Table 1 to Sec.   1037.106--CO2 Standards for Tractors Above 26,000 Pounds GVWR
----------------------------------------------------------------------------------------------------------------
                                                                                   CO2 standard
                                                                                   (g/ton-mile)    CO2 standard
                GVWR  (pounds)                            Sub-category               for model     (g/ton-mile)
                                                                                    years 2014-   for model year
                                                                                       2016       2017 and later
----------------------------------------------------------------------------------------------------------------
26,000  33,000.................................  Low-Roof Day Cab................              81              80
                                                Low-Roof Sleeper Cab............              68              66
                                                Mid-Roof Day Cab................              88              86
                                                Mid-Roof Sleeper Cab............              76              73
                                                High-Roof Day Cab...............              92              89
                                                High-Roof Sleeper Cab...........              75              72
----------------------------------------------------------------------------------------------------------------

    (c) No CH4 or N2O standards apply under this 
section. See 40 CFR part 1036 for CH4 or N2O 
standards that apply to engines used in these vehicles.
    (d) You may generate or use emission credits under the ABT program, 
as

[[Page 57404]]

described in subpart H of this part. This requires that you specify a 
Family Emission Limit (FEL) for each pollutant you include in the ABT 
program for each vehicle subfamily. The FEL may not be less than the 
result of emission modeling from Sec.  1037.520. These FELs serve as 
the emission standards for the specific vehicle subfamily instead of 
the standards specified in paragraph (a) of this section.
    (e) Your vehicles must meet the exhaust emission standards of this 
section throughout their full useful life, expressed in service miles 
or calendar years, whichever comes first. The following useful life 
values apply for the standards of this section:
    (1) 185,000 miles or 10 years, whichever comes first, for vehicles 
at or below 33,000 pounds GVWR.
    (2) 435,000 miles or 10 years, whichever comes first, for vehicles 
above 33,000 pounds GVWR.
    (f) You may optionally certify a tractor to the standards and 
useful life applicable to a higher vehicle service class (such as heavy 
heavy-duty instead of medium heavy-duty), provided you do not generate 
credits with the vehicle. If you include smaller vehicles in a credit-
generating subfamily (with an FEL below the standard), exclude its 
production volume from the credit calculation.

Sec.  1037.115  Other requirements.

    Vehicles required to meet the emission standards of this part must 
meet the following additional requirements, except as noted elsewhere 
in this part:
    (a) Adjustable parameters. Vehicles that have adjustable parameters 
must meet all the requirements of this part for any adjustment in the 
physically adjustable range. We may require that you set adjustable 
parameters to any specification within the adjustable range during any 
testing. See 40 CFR part 86 for information related to determining 
whether or not an operating parameter is considered adjustable. You 
must ensure safe vehicle operation throughout the physically adjustable 
range of each adjustable parameter, including consideration of 
production tolerances. Note that adjustable roof fairings are deemed 
not to be adjustable parameters.
    (b) Prohibited controls. You may not design your vehicles with 
emission control devices, systems, or elements of design that cause or 
contribute to an unreasonable risk to public health, welfare, or safety 
while operating. For example, this would apply if the vehicle emits a 
noxious or toxic substance it would otherwise not emit that contributes 
to such an unreasonable risk.
    (c) Air conditioning leakage. Loss of refrigerant from your air 
conditioning systems may not exceed 1.50 percent per year, except as 
allowed by paragraphs (c)(2) and (3) of this section. Calculate the 
total leakage rate in g/year as specified in 40 CFR 86.166. Calculate 
the percent leakage rate as: [total leakage rate (g/yr)] / [total 
refrigerant capacity (g)] x 100. Round your leakage rate to the nearest 
one-hundredth of a percent. See Sec.  1037.150 for vocational vehicles.
    (1) For purpose of this requirement, ``refrigerant capacity'' is 
the total mass of refrigerant recommended by the vehicle manufacturer 
as representing a full charge. Where full charge is specified as a 
pressure, use good engineering judgment to convert the pressure and 
system volume to a mass.
    (2) If your system uses a refrigerant other than HFC-134a, adjust 
your leakage rate by multiplying it by the global warming potential of 
your refrigerant and dividing the product by 1430 (which is the global 
warming potential of HFC-134a). Apply this adjustment before comparing 
your leakage rate to the standard. Determine global warming potentials 
consistent with 40 CFR 86.1866. Note that global warming potentials 
represent the equivalent grams of CO2 that would have the 
same global warming impact (over 100 years) as one gram of the 
refrigerant.
    (3) If your total refrigerant capacity is less than 734 grams, your 
leakage rate may exceed 1.50 percent, as long as the total leakage rate 
does not exceed 11.0 g/yr. If your system uses a refrigerant other than 
HFC-134a, you may adjust your leakage rate as specified in paragraph 
(c)(2) of this section.

Sec.  1037.120  Emission-related warranty requirements.

    (a) General requirements. You must warrant to the ultimate 
purchaser and each subsequent purchaser that the new vehicle, including 
all parts of its emission control system, meets two conditions:
    (1) It is designed, built, and equipped so it conforms at the time 
of sale to the ultimate purchaser with the requirements of this part.
    (2) It is free from defects in materials and workmanship that cause 
the vehicle to fail to conform to the requirements of this part during 
the applicable warranty period.
    (b) Warranty period. (1) Your emission-related warranty must be 
valid for at least:
    (i) 5 years or 50,000 miles for spark-ignition vehicles and light 
heavy-duty vehicles.
    (ii) 5 years or 100,000 miles for medium and heavy heavy-duty 
vehicles.
    (iii) 2 years or 24,000 miles for tires.
    (2) You may offer an emission-related warranty more generous than 
we require. The emission-related warranty for the vehicle may not be 
shorter than any basic mechanical warranty you provide to that owner 
without charge for the vehicle. Similarly, the emission-related 
warranty for any component may not be shorter than any warranty you 
provide to that owner without charge for that component. This means 
that your warranty for a given vehicle may not treat emission-related 
and non-emission-related defects differently for any component. The 
warranty period begins when the vehicle is placed into service.
    (c) Components covered. The emission-related warranty covers 
vehicle speed limiters, idle shutdown systems, fairings, and hybrid 
system components, to the extent such emission-related components are 
included in the certified emission controls. The emission-related 
warranty covers all components whose failure would increase a vehicle's 
emissions of air conditioning refrigerants for vehicles subject to air 
conditioning leakage standards. The emission-related warranty covers 
tires and all components whose failure would increase a vehicle's 
evaporative emissions (for vehicles subject to evaporative emission 
standards). The emission-related warranty covers these components even 
if another company produces the component. Your emission-related 
warranty does not need to cover components whose failure would not 
increase a vehicle's emissions of any regulated pollutant.
    (d) Limited applicability. You may deny warranty claims under this 
section if the operator caused the problem through improper maintenance 
or use, as described in 40 CFR 1068.115.
    (e) Owner's manual. Describe in the owners manual the emission-
related warranty provisions from this section that apply to the 
vehicle.

Sec.  1037.125  Maintenance instructions and allowable maintenance.

    Give the ultimate purchaser of each new vehicle written 
instructions for properly maintaining and using the vehicle, including 
the emission control system. The maintenance instructions also apply to 
service accumulation on any of your emission-data vehicles. See 
paragraph (i) of this section for

[[Page 57405]]

requirements related to tire replacement.
    (a) Critical emission-related maintenance. Critical emission-
related maintenance includes any adjustment, cleaning, repair, or 
replacement of critical emission-related components. This may also 
include additional emission-related maintenance that you determine is 
critical if we approve it in advance. You may schedule critical 
emission-related maintenance on these components if you demonstrate 
that the maintenance is reasonably likely to be done at the recommended 
intervals on in-use vehicles. We will accept scheduled maintenance as 
reasonably likely to occur if you satisfy any of the following 
conditions:
    (1) You present data showing that, if a lack of maintenance 
increases emissions, it also unacceptably degrades the vehicle's 
performance.
    (2) You present survey data showing that at least 80 percent of 
vehicles in the field get the maintenance you specify at the 
recommended intervals.
    (3) You provide the maintenance free of charge and clearly say so 
in your maintenance instructions.
    (4) You otherwise show us that the maintenance is reasonably likely 
to be done at the recommended intervals.
    (b) Recommended additional maintenance. You may recommend any 
additional amount of maintenance on the components listed in paragraph 
(a) of this section, as long as you state clearly that these 
maintenance steps are not necessary to keep the emission-related 
warranty valid. If operators do the maintenance specified in paragraph 
(a) of this section, but not the recommended additional maintenance, 
this does not allow you to disqualify those vehicles from in-use 
testing or deny a warranty claim. Do not take these maintenance steps 
during service accumulation on your emission-data vehicles.
    (c) Special maintenance. You may specify more frequent maintenance 
to address problems related to special situations, such as atypical 
vehicle operation. You must clearly state that this additional 
maintenance is associated with the special situation you are 
addressing. We may disapprove your maintenance instructions if we 
determine that you have specified special maintenance steps to address 
vehicle operation that is not atypical, or that the maintenance is 
unlikely to occur in use. If we determine that certain maintenance 
items do not qualify as special maintenance under this paragraph (c), 
you may identify this as recommended additional maintenance under 
paragraph (b) of this section.
    (d) Noncritical emission-related maintenance. Subject to the 
provisions of this paragraph (d), you may schedule any amount of 
emission-related inspection or maintenance that is not covered by 
paragraph (a) of this section (that is, maintenance that is neither 
explicitly identified as critical emission-related maintenance, nor 
that we approve as critical emission-related maintenance). Noncritical 
emission-related maintenance generally includes maintenance on the 
components we specify in 40 CFR part 1068, Appendix I, that is not 
covered in paragraph (a) of this section. You must state in the owners 
manual that these steps are not necessary to keep the emission-related 
warranty valid. If operators fail to do this maintenance, this does not 
allow you to disqualify those vehicles from in-use testing or deny a 
warranty claim. Do not take these inspection or maintenance steps 
during service accumulation on your emission-data vehicles.
    (e) Maintenance that is not emission-related. For maintenance 
unrelated to emission controls, you may schedule any amount of 
inspection or maintenance. You may also take these inspection or 
maintenance steps during service accumulation on your emission-data 
vehicles, as long as they are reasonable and technologically necessary. 
You may perform this non-emission-related maintenance on emission-data 
vehicles at the least frequent intervals that you recommend to the 
ultimate purchaser (but not the intervals recommended for severe 
service).
    (f) Source of parts and repairs. State clearly on the first page of 
your written maintenance instructions that a repair shop or person of 
the owner's choosing may maintain, replace, or repair emission control 
devices and systems. Your instructions may not require components or 
service identified by brand, trade, or corporate name. Also, do not 
directly or indirectly condition your warranty on a requirement that 
the vehicle be serviced by your franchised dealers or any other service 
establishments with which you have a commercial relationship. You may 
disregard the requirements in this paragraph (f) if you do one of two 
things:
    (1) Provide a component or service without charge under the 
purchase agreement.
    (2) Get us to waive this prohibition in the public's interest by 
convincing us the vehicle will work properly only with the identified 
component or service.
    (g) [Reserved]
    (h) Owner's manual. Explain the owner's responsibility for proper 
maintenance in the owner's manual.
    (i) Tire maintenance and replacement. Include instructions that 
will enable the owner to replace tires so that the vehicle conforms to 
the original certified vehicle configuration.

Sec.  1037.135  Labeling.

    (a) Assign each vehicle a unique identification number and 
permanently affix, engrave, or stamp it on the vehicle in a legible 
way. The vehicle identification number (VIN) serves this purpose.
    (b) At the time of manufacture, affix a permanent and legible label 
identifying each vehicle. The label must be--
    (1) Attached in one piece so it is not removable without being 
destroyed or defaced.
    (2) Secured to a part of the vehicle needed for normal operation 
and not normally requiring replacement.
    (3) Durable and readable for the vehicle's entire life.
    (4) Written in English.
    (c) The label must--
    (1) Include the heading ``VEHICLE EMISSION CONTROL INFORMATION''.
    (2) Include your full corporate name and trademark. You may 
identify another company and use its trademark instead of yours if you 
comply with the branding provisions of 40 CFR 1068.45.
    (3) Include EPA's standardized designation for the vehicle family.
    (4) State the regulatory sub-category that determines the 
applicable emission standards for the vehicle family (see definition in 
Sec.  1037.801).
    (5) State the date of manufacture [DAY (optional), MONTH, and 
YEAR]. You may omit this from the label if you stamp, engrave, or 
otherwise permanently identify it elsewhere on the engine, in which 
case you must also describe in your application for certification where 
you will identify the date on the engine.
    (6) Identify the emission control system. Use terms and 
abbreviations as described in Appendix III to this part or other 
applicable conventions.
    (7) Identify any requirements for fuel and lubricants that do not 
involve fuel-sulfur levels.
    (8) State: ``THIS VEHICLE COMPLIES WITH U.S. EPA REGULATIONS FOR 
[MODEL YEAR] HEAVY-DUTY VEHICLES.''
    (9) Include the following statement, if applicable: ``THIS VEHICLE 
IS

[[Page 57406]]

DESIGNED TO COMPLY WITH EVAPORATIVE EMISSION STANDARDS WITH UP TO x 
GALLONS OF FUEL TANK CAPACITY.'' Complete this statement by identifying 
the maximum specified fuel tank capacity associated with your 
certification.
    (d) You may add information to the emission control information 
label to identify other emission standards that the vehicle meets or 
does not meet (such as European standards). You may also add other 
information to ensure that the vehicle will be properly maintained and 
used.
    (e) You may ask us to approve modified labeling requirements in 
this part 1037 if you show that it is necessary or appropriate. We will 
approve your request if your alternate label is consistent with the 
requirements of this part.

Sec.  1037.140  Curb weight and roof height.

    (a) Where applicable, a vehicle's curb weight and roof height are 
determined from nominal design specifications, as provided in this 
section. Round the weight to the nearest pound and height to the 
nearest inch. Base roof height on fully inflated tires having a static 
loaded radius equal to the arithmetic mean of the largest and smallest 
static loaded radius of tires you offer or a standard tire we approve.
    (b) The nominal design specifications must be within the range of 
the actual weights and roof heights of production vehicles considering 
normal production variability. If after production begins it is 
determined that your nominal design specifications do not represent 
production vehicles, we may require you to amend your application for 
certification under Sec.  1037.225.
    (c) If your vehicle is equipped with an adjustable roof fairing, 
measure the roof height with the fairing in its lowest setting.

Sec.  1037.150  Interim provisions.

    The provisions in this section apply instead of other provisions in 
this part.
    (a) Incentives for early introduction. The provisions of this 
paragraph (a) apply with respect to vehicles produced in model years 
before 2014. Manufacturers may voluntarily certify in model year 2013 
(or earlier model years for electric vehicles) to the greenhouse gas 
standards of this part.
    (1) This paragraph (a)(1) applies for regulatory sub-categories 
subject to the standards of Sec.  1037.105 or Sec.  1037.106. Except as 
specified in paragraph (a)(3) of this section, to generate early 
credits under this paragraph for any vehicles other than electric 
vehicles, you must certify your entire U.S.-directed production volume 
within the regulatory sub-category to these standards. Except as 
specified in paragraph (a)(4) of this section, if some vehicle families 
within a regulatory sub-category are certified after the start of the 
model year, you may generate credits only for production that occurs 
after all families are certified. For example, if you produce three 
vehicle families in an averaging set and you receive your certificates 
for those families on January 4, 2013, March 15, 2013, and April 24, 
2013, you may not generate credits for model year 2013 production in 
any of the families that occurs before April 24, 2013. Calculate 
credits relative to the standard that would apply in model year 2014 
using the equations in subpart H of this part. You may bank credits 
equal to the surplus credits you generate under this paragraph (a) 
multiplied by 1.50. For example, if you have 1.0 Mg of surplus credits 
for model year 2013, you may bank 1.5 Mg of credits. Credit deficits 
for an averaging set prior to model year 2014 do not carry over to 
model year 2014. These credits may be used to show compliance with the 
standards of this part for 2014 and later model years. We recommend 
that you notify EPA of your intent to use this provision before 
submitting your applications.
    (2) This paragraph (a)(2) applies for regulatory sub-categories 
subject to the standards of Sec.  1037.104. To generate early credits 
under this paragraph (a)(2) for any vehicles other than electric 
vehicles, you must certify your entire U.S.-directed production volume 
within the regulatory sub-category to these standards. If you calculate 
a separate fleet average for advanced-technology vehicles under Sec.  
1037.104(c)(7), you must certify your entire U.S.-directed production 
volume of both advanced and conventional vehicles within the regulatory 
sub-category. Except as specified in paragraph (a)(4) of this section, 
if some test groups are certified after the start of the model year, 
you may generate credits only for production that occurs after all test 
groups are certified. For example, if you produce three test groups in 
an averaging set and you receive your certificates for those test 
groups on January 4, 2013, March 15, 2013, and April 24, 2013, you may 
not generate credits for model year 2013 production in any of the test 
groups that occurs before April 24, 2013. Calculate credits relative to 
the standard that would apply in model year 2014 using the applicable 
equations in 40 CFR part 86 and your model year 2013 U.S.-directed 
production volumes. These credits may be used to show compliance with 
the standards of this part for 2014 and later model years. We recommend 
that you notify EPA of your intent to use this provision before 
submitting your applications.
    (3) You may generate emission credits for the number of additional 
SmartWay designated tractors (relative to your 2012 production), 
provided you do not generate credits for those vehicles under paragraph 
(a)(1) of this section. Calculate credits for each regulatory sub-
category relative to the standard that would apply in model year 2014 
using the equations in subpart H of this part. Use a production volume 
equal to the number of designated model year 2013 SmartWay tractors 
minus the number of designated model year 2012 SmartWay tractors. You 
may bank credits equal to the surplus credits you generate under this 
paragraph (a)(3) multiplied by 1.50. Your 2012 and 2013 model years 
must be equivalent in length.
    (4) This paragraph (a)(4) applies where you do not receive your 
final certificate in a regulatory sub-category within 30 days of 
submitting your final application for that sub-category. Calculate your 
credits for all production that occurs 30 days or more after you submit 
your final application for the sub-category.
    (b) Phase-in provisions. Each manufacturer must choose one of the 
following options for phasing in the standards of Sec.  1037.104:
    (1) To implement the phase-in under this paragraph (b)(1), the 
standards in Sec.  1037.104 apply as specified for model year 2018, 
with compliance for vehicles in model years 2014 through 2017 based on 
the CO2 target values specified in the following table:

                       Table 1 to Sec.   1037.150
------------------------------------------------------------------------
    Model year and engine cycle         Alternate CO2 target (g/mile)
------------------------------------------------------------------------
2014 Spark-Ignition................  [0.0482 x (WF)] + 371
2015 Spark-Ignition................  [0.0479 x (WF)] + 369

[[Page 57407]]

 
2016 Spark-Ignition................  [0.0469 x (WF)] + 362
2017 Spark-Ignition................  [0.0460 x (WF)] + 354
2014 Compression-Ignition..........  [0.0478 x (WF)] + 368
2015 Compression-Ignition..........  [0.0474 x (WF)] + 366
2016 Compression-Ignition..........  [0.0460 x (WF)] + 354
2017 Compression-Ignition..........  [0.0445 x (WF)] + 343
------------------------------------------------------------------------

    (2) To implement the phase-in under this paragraph (b)(2), the 
standards in Sec.  1037.104 apply as specified for model year 2019, 
with compliance for vehicles in model years 2014 through 2018 based on 
the CO2 target values specified in the following table:

                       Table 2 to Sec.   1037.150
------------------------------------------------------------------------
    Model year and engine cycle         Alternate CO2 target (g/mile)
------------------------------------------------------------------------
2014 Spark-Ignition................  [0.0482 x (WF)] + 371
2015 Spark-Ignition................  [0.0479 x (WF)] + 369
2016-2018 Spark-Ignition...........  [0.0456 x (WF)] + 352
2014 Compression-Ignition..........  [0.0478 x (WF)] + 368
2015 Compression-Ignition..........  [0.0474 x (WF)] + 366
2016-2018 Compression-Ignition.....  [0.0440 x (WF)] + 339
------------------------------------------------------------------------

    (c) Provisions for small manufacturers. Manufacturers meeting the 
small business criteria specified in 13 CFR 121.201 for ``Heavy Duty 
Truck Manufacturing'' are not subject to the greenhouse gas standards 
of Sec. Sec.  1037.104 through 1037.106, as specified in this paragraph 
(c). Qualifying manufacturers must notify the Designated Compliance 
Officer each model year before introducing these excluded vehicles into 
U.S. commerce. This notification must include a description of the 
manufacturer's qualification as a small business under 13 CFR 121.201. 
You must label your excluded vehicles with the following statement: 
``THIS VEHICLE IS EXCLUDED UNDER 40 CFR 1037.150(c).''.
    (d) Air conditioning leakage for vocational vehicles. The air 
conditioning leakage standard of Sec.  1037.115 does not apply for 
vocational vehicles.
    (e) Model year 2014 N2O standards. In model year 2014 
and earlier, manufacturers may show compliance with the N2O 
standards using an engineering analysis. This allowance also applies 
for later test groups families carried over from model 2014 consistent 
with the provisions of 40 CFR 86.1839. You may not certify to an 
N2O FEL different than the standard without measuring 
N2O emissions.
    (f) Electric vehicles. All electric vehicles are deemed to have 
zero emissions of CO2, CH4, and N2O. 
No emission testing is required for electric vehicles.
    (g) Compliance date. Compliance with the standards of this part is 
optional prior to January 1, 2014. This means that if your 2014 model 
year begins before January 1, 2014, you may certify for a partial model 
year that begins on January 1, 2014 and ends on the day your model year 
would normally end. You must label model year 2014 vehicles excluded 
under this paragraph (g) with the following statement: ``THIS VEHICLE 
IS EXCLUDED UNDER 40 CFR 1037.150(g).''
    (h) Off-road vehicle exemption. In unusual circumstances, vehicle 
manufacturers may ask us to exempt vehicles under Sec.  1037.631 based 
on other criteria that are equivalent to those specified in Sec.  
1037.631(a). For example, we would normally not grant relief in cases 
where the vehicle manufacturer had credits or other compliant tires 
were available.
    (i) Credit multiplier for advanced technology. If you generate 
credits from vehicles certified with advanced technology, you may 
multiply these credits by 1.50, except that you may not apply this 
multiplier in addition to the early-credit multiplier of paragraph (a) 
of this section.
    (j) Limited prohibition related to early model year engines. The 
prohibition in Sec.  1037.601 against introducing into U.S. commerce a 
vehicle containing an engine not certified to the standards of this 
part does not apply for vehicles using model year 2014 or 2015 spark-
ignition engines, or any model year 2013 or earlier engines.
    (k) Verifying drag areas from in-use vehicles. We may measure the 
drag area of your vehicles after they have been placed into service. 
Your vehicle conforms to the regulations of this part with respect to 
aerodynamic performance if we measure its drag area to be at or below 
the maximum drag area allowed for the bin to which that configuration 
was certified. To account for measurement variability, your vehicle is 
also deemed to conform to the regulations of this part with respect to 
aerodynamic performance if we measure its drag area to at or below the 
maximum drag area allowed for the bin above the bin to which you 
certified (for example, Bin II if you certified the vehicle to Bin 
III), unless we determine that you knowingly produced the vehicle to 
have a higher drag area than is allowed for the bin to which it was 
certified.
    (l) Optional certification under Sec.  1037.104. You may certify 
certain complete or cab-complete vehicles to the standards of Sec.  
1037.104. All vehicles optionally certified under this paragraph (l) 
are deemed to be subject to the standards of Sec.  1037.104. Note that 
certification under this paragraph (l) does not affect how you may or 
may not certify with respect to criteria pollutants. For example, 
certifying a Class 4 vehicle under this paragraph does not allow you to 
chassis-certify these vehicles with respect to criteria emissions.
    (1) You may certify complete or cab-complete spark-ignition 
vehicles to the standards of Sec.  1037.104.
    (2) You may apply the provisions of Sec.  1037.104 to cab-complete 
vehicles based on a complete sister vehicle. In unusual circumstances, 
you may ask us to apply these provisions to Class 2b or

[[Page 57408]]

3 incomplete vehicles that do not meet the definition of cab-complete. 
Except as specified in paragraph (l)(3) of this section, for purposes 
of Sec.  1037.104, a complete sister vehicle is a complete vehicle of 
the same vehicle configuration (as defined in Sec.  1037.104) as the 
cab-complete vehicle. Calculate the target value under Sec.  
1037.104(a) based on the same work factor value that applies for the 
complete sister vehicle. Test these cab-complete vehicles using the 
same equivalent test weight and other dynamometer settings that apply 
for the complete vehicle from which you used the work factor value. For 
certification, you may submit the test data from that complete sister 
vehicle instead of performing the test on the cab-complete vehicle. You 
are not required to produce the complete sister vehicle for sale to use 
the provisions of this paragraph (l)(2). This means the complete sister 
vehicle may be a carryover vehicle from a prior model year or a vehicle 
created solely for the purpose of testing.
    (3) You may use as complete sister vehicle a complete vehicle that 
is not of the same vehicle configuration as the cab-complete vehicle as 
specified in this paragraph (l)(3). This allowance applies where the 
complete vehicle is not of the same vehicle configuration as the cab-
complete vehicle only because of factors unrelated to coastdown 
performance. If your complete sister vehicle is covered by this 
paragraph (l)(3), you may not submit the test data from that complete 
sister vehicle and must perform the test on the cab-complete vehicle.
    (m) Loose engine sales. This paragraph (m) applies for spark-
ignition engines identical to engines used in vehicles certified to the 
standards of Sec.  1037.104, where you sell such engines as loose 
engines or as engines installed in incomplete vehicles that are not 
cab-complete vehicles. For purposes of this paragraph (m), engines 
would not be considered to be identical if they used different engine 
hardware. You may include such engines in a test group certified to the 
standards of Sec.  1037.104, subject to the following provisions:
    (1) Engines certified under this paragraph (m) are deemed to be 
certified to the standards of 40 CFR 1036.108 as specified in 40 CFR 
1036.108(a)(4).
    (2) The U.S.-directed production volume of engines you sell as 
loose engines or installed in incomplete heavy-duty vehicles that are 
not cab-complete vehicles in any given model year may not exceed ten 
percent of the total U.S.-directed production volume of engines of that 
design that you produce for heavy-duty applications for that model 
year, including engines you produce for complete vehicles, cab-complete 
vehicles, and other incomplete vehicles. The total number of engines 
you may certify under this paragraph (m), of all engine designs, may 
not exceed 15,000 in any model year. Engines produced in excess of 
either of these limits are not covered by your certificate. For 
example, if you produce 80,000 complete model year 2017 Class 2b pickup 
trucks with a certain engine and 10,000 incomplete model year 2017 
Class 3 vehicles with that same engine, and you do not apply the 
provisions of this paragraph (m) to any other engine designs, you may 
produce up to 10,000 engines of that design for sale as loose engines 
under this paragraph (m). If you produced 11,000 engines of that design 
for sale as loose engines, the last 1,000 of them that you produced in 
that model year 2017 would be considered uncertified.
    (3) This paragraph (m) does not apply for engines certified to the 
standards of 40 CFR 1036.108(a)(1).
    (4) Label the engines as specified in 40 CFR 1036.135 including the 
following compliance statement: ``THIS ENGINE WAS CERTIFIED TO THE 
ALTERNATE GREENHOUSE GAS EMISSION STANDARDS OF 40 CFR 1036.108(a)(4).'' 
List the test group name instead of an engine family name.
    (5) Vehicles using engines certified under this paragraph (m) are 
subject to the emission standards of Sec.  1037.105.
    (6) For certification purposes, your engines are deemed to have a 
CO2 target value and test result equal to the CO2 
target value and test result for the complete vehicle in the applicable 
test group with the highest equivalent test weight, except as specified 
in paragraph (m)(6)(ii) of this section. Use these values to calculate 
your target value, fleet-average emission rate, and in-use emission 
standard. Where there are multiple complete vehicles with the same 
highest equivalent test weight, select the CO2 target value 
and test result as specified in paragraphs (m)(6)(i) and (ii) of this 
section:
    (i) If one or more of the CO2 test results exceed the 
applicable target value, use the CO2 target value and test 
result of the vehicle that exceeds its target value by the greatest 
amount.
    (ii) If none of the CO2 test results exceed the 
applicable target value, select the highest target value and set the 
test result equal to it. This means that you may not generate emission 
credits from vehicles certified under this paragraph (m).
    (7) State in your applications for certification that your test 
group and engine family will include engines certified under this 
paragraph (m). This applies for your greenhouse gas vehicle test group 
and your criteria pollutant engine family. List in each application the 
name of the corresponding test group/engine family.

Subpart C--Certifying Vehicle families

Sec.  1037.201  General requirements for obtaining a certificate of 
conformity.

    (a) You must send us a separate application for a certificate of 
conformity for each vehicle family. A certificate of conformity is 
valid from the indicated effective date until the end of the model year 
for which it is issued, which may not extend beyond December 31 of that 
year. You must renew your certification annually for any vehicles you 
continue to produce.
    (b) The application must contain all the information required by 
this part and must not include false or incomplete statements or 
information (see Sec.  1037.255).
    (c) We may ask you to include less information than we specify in 
this subpart, as long as you maintain all the information required by 
Sec.  1037.250.
    (d) You must use good engineering judgment for all decisions 
related to your application (see 40 CFR 1068.5).
    (e) An authorized representative of your company must approve and 
sign the application.
    (f) See Sec.  1037.255 for provisions describing how we will 
process your application.
    (g) We may perform confirmatory testing on your vehicles; for 
example, we may test vehicles to verify drag areas or other GEM inputs. 
We may require you to deliver your test vehicles to a facility we 
designate for our testing. Alternatively, you may choose to deliver 
another vehicle that is identical in all material respects to the test 
vehicle. Where certification is based on testing components such as 
tires, we may require you to deliver test components to a facility we 
designate for our testing.

Sec.  1037.205  What must I include in my application?

    This section specifies the information that must be in your 
application, unless we ask you to include less information under Sec.  
1037.201(c). We may require you to provide additional information to 
evaluate your application. Note that references to testing and 
emission-data vehicles refer to testing vehicles to measure aerodynamic 
drag, assess hybrid vehicle performance, and/or measure evaporative 
emissions.
    (a) Describe the vehicle family's specifications and other basic 
parameters of the vehicle's design and emission controls. List the fuel 
type on

[[Page 57409]]

which your vehicles are designed to operate (for example, ultra low-
sulfur diesel fuel).
    (b) Explain how the emission control system operates. As 
applicable, describe in detail all system components for controlling 
greenhouse gas and evaporative emissions, including all auxiliary 
emission control devices (AECDs) and all fuel-system components you 
will install on any production vehicle. Identify the part number of 
each component you describe. For this paragraph (b), treat as separate 
AECDs any devices that modulate or activate differently from each 
other.
    (c) For vehicles subject to air conditioning standards, include:
    (1) The refrigerant leakage rates (leak scores).
    (2) The refrigerant capacity of the air conditioning systems.
    (3) The corporate name of the final installer of the air 
conditioning system.
    (d) Describe any vehicles you selected for testing and the reasons 
for selecting them.
    (e) Describe any test equipment and procedures that you used, 
including any special or alternate test procedures you used (see Sec.  
1037.501).
    (f) Describe how you operated any emission-data vehicle before 
testing, including the duty cycle and the number of vehicle operating 
miles used to stabilize emission levels. Explain why you selected the 
method of service accumulation. Describe any scheduled maintenance you 
did.
    (g) List the specifications of any test fuel to show that it falls 
within the required ranges we specify in 40 CFR part 1065.
    (h) Identify the vehicle family's useful life.
    (i) Include the maintenance instructions and warranty statement you 
will give to the ultimate purchaser of each new vehicle (see Sec. Sec.  
1037.120 and 1037.125).
    (j) Describe your emission control information label (see Sec.  
1037.135).
    (k) Identify the emission standards or FELs to which you are 
certifying vehicles in the vehicle family. For families containing 
multiple subfamilies, this means that you must identify multiple 
CO2 FELs. For example, you may identify the highest and 
lowest FELs to which any of your subfamilies will be certified and also 
list all possible FELs in between (which will be in 1 g/ton-mile 
increments).
    (l) Where applicable, identify the vehicle family's deterioration 
factors and describe how you developed them. Present any emission test 
data you used for this (see Sec.  1037.241(c)).
    (m) Where applicable, state that you operated your emission-data 
vehicles as described in the application (including the test 
procedures, test parameters, and test fuels) to show you meet the 
requirements of this part.
    (n) Present evaporative test data to show your vehicles meet the 
evaporative emission standards we specify in subpart B of this part, if 
applicable. Report all valid test results from emission-data vehicles 
and indicate whether there are test results from invalid tests or from 
any other tests of the emission-data vehicle, whether or not they were 
conducted according to the test procedures of subpart F of this part. 
We may require you to report these additional test results. We may ask 
you to send other information to confirm that your tests were valid 
under the requirements of this part and 40 CFR part 86.
    (o) Report modeling results for ten configurations. Include 
modeling inputs and detailed descriptions of how they were derived. 
Unless we specify otherwise, include the configuration with the highest 
modeling result, the lowest modeling result, and the configurations 
with the highest projected sales.
    (p) Describe all adjustable operating parameters (see Sec.  
1037.115), including production tolerances. You do not need to include 
parameters that do not affect emissions covered by your application. 
Include the following in your description of each parameter:
    (1) The nominal or recommended setting.
    (2) The intended physically adjustable range.
    (3) The limits or stops used to establish adjustable ranges.
    (4) Information showing why the limits, stops, or other means of 
inhibiting adjustment are effective in preventing adjustment of 
parameters on in-use vehicles to settings outside your intended 
physically adjustable ranges.
    (q) [Reserved]
    (r) Unconditionally certify that all the vehicles in the vehicle 
family comply with the requirements of this part, other referenced 
parts of the CFR, and the Clean Air Act.
    (s) Include good-faith estimates of U.S.-directed production 
volumes by subfamily. We may require you to describe the basis of your 
estimates.
    (t) Include the information required by other subparts of this 
part. For example, include the information required by Sec.  1037.725 
if you participate in the ABT program.
    (u) Include other applicable information, such as information 
specified in this part or 40 CFR part 1068 related to requests for 
exemptions.
    (v) Name an agent for service located in the United States. Service 
on this agent constitutes service on you or any of your officers or 
employees for any action by EPA or otherwise by the United States 
related to the requirements of this part.

Sec.  1037.210  Preliminary approval before certification.

    If you send us information before you finish the application, we 
may review it and make any appropriate determinations. Decisions made 
under this section are considered to be preliminary approval, subject 
to final review and approval. We will generally not reverse a decision 
where we have given you preliminary approval, unless we find new 
information supporting a different decision. If you request preliminary 
approval related to the upcoming model year or the model year after 
that, we will make best-efforts to make the appropriate determinations 
as soon as practicable. We will generally not provide preliminary 
approval related to a future model year more than two years ahead of 
time.

Sec.  1037.220  Amending maintenance instructions.

    You may amend your emission-related maintenance instructions after 
you submit your application for certification as long as the amended 
instructions remain consistent with the provisions of Sec.  1037.125. 
You must send the Designated Compliance Officer a written request to 
amend your application for certification for a vehicle family if you 
want to change the emission-related maintenance instructions in a way 
that could affect emissions. In your request, describe the proposed 
changes to the maintenance instructions. If operators follow the 
original maintenance instructions rather than the newly specified 
maintenance, this does not allow you to disqualify those vehicles from 
in-use testing or deny a warranty claim.
    (a) If you are decreasing or eliminating any specified maintenance, 
you may distribute the new maintenance instructions to your customers 
30 days after we receive your request, unless we disapprove your 
request. This would generally include replacing one maintenance step 
with another. We may approve a shorter time or waive this requirement.
    (b) If your requested change would not decrease the specified 
maintenance, you may distribute the new maintenance instructions 
anytime after you send your request. For example,

[[Page 57410]]

this paragraph (b) would cover adding instructions to increase the 
frequency of filter changes for vehicles in severe-duty applications.
    (c) You need not request approval if you are making only minor 
corrections (such as correcting typographical mistakes), clarifying 
your maintenance instructions, or changing instructions for maintenance 
unrelated to emission control. We may ask you to send us copies of 
maintenance instructions revised under this paragraph (c).

Sec.  1037.225  Amending applications for certification.

    Before we issue you a certificate of conformity, you may amend your 
application to include new or modified vehicle configurations, subject 
to the provisions of this section. After we have issued your 
certificate of conformity, you may send us an amended application 
requesting that we include new or modified vehicle configurations 
within the scope of the certificate, subject to the provisions of this 
section. You must amend your application if any changes occur with 
respect to any information that is included or should be included in 
your application.
    (a) You must amend your application before you take any of the 
following actions:
    (1) Add a vehicle configuration to a vehicle family. In this case, 
the vehicle configuration added must be consistent with other vehicle 
configurations in the vehicle family with respect to the criteria 
listed in Sec.  1037.230.
    (2) Change a vehicle configuration already included in a vehicle 
family in a way that may affect emissions, or change any of the 
components you described in your application for certification. This 
includes production and design changes that may affect emissions any 
time during the vehicle's lifetime.
    (3) Modify an FEL for a vehicle family as described in paragraph 
(f) of this section.
    (b) To amend your application for certification, send the relevant 
information to the Designated Compliance Officer.
    (1) Describe in detail the addition or change in the vehicle model 
or configuration you intend to make.
    (2) Include engineering evaluations or data showing that the 
amended vehicle family complies with all applicable requirements. You 
may do this by showing that the original emission-data vehicle is still 
appropriate for showing that the amended family complies with all 
applicable requirements.
    (3) If the original emission-data vehicle or emission modeling for 
the vehicle family is not appropriate to show compliance for the new or 
modified vehicle configuration, include new test data or emission 
modeling showing that the new or modified vehicle configuration meets 
the requirements of this part.
    (c) We may ask for more test data or engineering evaluations. You 
must give us these within 30 days after we request them.
    (d) For vehicle families already covered by a certificate of 
conformity, we will determine whether the existing certificate of 
conformity covers your newly added or modified vehicle. You may ask for 
a hearing if we deny your request (see Sec.  1037.820).
    (e) For vehicle families already covered by a certificate of 
conformity, you may start producing the new or modified vehicle 
configuration anytime after you send us your amended application and 
before we make a decision under paragraph (d) of this section. However, 
if we determine that the affected vehicles do not meet applicable 
requirements, we will notify you to cease production of the vehicles 
and may require you to recall the vehicles at no expense to the owner. 
Choosing to produce vehicles under this paragraph (e) is deemed to be 
consent to recall all vehicles that we determine do not meet applicable 
emission standards or other requirements and to remedy the 
nonconformity at no expense to the owner. If you do not provide 
information required under paragraph (c) of this section within 30 days 
after we request it, you must stop producing the new or modified 
vehicles.
    (f) You may ask us to approve a change to your FEL in certain cases 
after the start of production. The changed FEL may not apply to 
vehicles you have already introduced into U.S. commerce, except as 
described in this paragraph (f). You may ask us to approve a change to 
your FEL in the following cases:
    (1) You may ask to raise your FEL for your vehicle subfamily at any 
time. In your request, you must show that you will still be able to 
meet the emission standards as specified in subparts B and H of this 
part. Use the appropriate FELs with corresponding production volumes to 
calculate emission credits for the model year, as described in subpart 
H of this part.
    (2) Where testing applies, you may ask to lower the FEL for your 
vehicle subfamily only if you have test data from production vehicles 
showing that emissions are below the proposed lower FEL. Otherwise, you 
may ask to lower your FEL for your vehicle subfamily at any time. The 
lower FEL applies only to vehicles you produce after we approve the new 
FEL. Use the appropriate FELs with corresponding production volumes to 
calculate emission credits for the model year, as described in subpart 
H of this part.
    (3) You may ask to add an FEL for your vehicle family at any time.

Sec.  1037.230  Vehicle families, sub-families, and configurations.

    (a) For purposes of certifying your vehicles to greenhouse gas 
standards, divide your product line into families of vehicles as 
specified in this section. Your vehicle family is limited to a single 
model year. Group vehicles in the same vehicle family if they are the 
same in all the following aspects:
    (1) The regulatory sub-category (or equivalent in the case of 
vocational tractors), as follows:
    (i) Vocational vehicles at or below 19,500 pounds GVWR.
    (ii) Vocational vehicles (other than vocational tractors) above 
19,500 pounds GVWR and at or below 33,000 pounds GVWR.
    (iii) Vocational vehicles (other than vocational tractors) above 
33,000 pounds GVWR.
    (iv) Low-roof tractors above 26,000 pounds GVWR and at or below 
33,000 pounds GVWR.
    (v) Mid-roof tractors above 26,000 pounds GVWR and at or below 
33,000 pounds GVWR.
    (vi) High-roof tractors above 26,000 pounds GVWR and at or below 
33,000 pounds GVWR.
    (vii) Low-roof day cab tractors above 33,000 pounds GVWR.
    (viii) Low-roof sleeper cab tractors above 33,000 pounds GVWR.
    (ix) Mid-roof day cab tractors above 33,000 pounds GVWR.
    (x) Mid-roof sleeper cab tractors above 33,000 pounds GVWR.
    (xi) High-roof day cab tractors above 33,000 pounds GVWR.
    (xii) High-roof sleeper cab tractors above 33,000 pounds GVWR.
    (xiii) Vocational tractors.
    (2) Vehicle technology as follows:
    (i) Group together vehicles that do not contain advanced or 
innovative technologies.
    (ii) Group together vehicles that contain the same advanced/
innovative technologies.
    (b) If the vehicles in your family are being certified to more than 
one FEL, subdivide your greenhouse gas vehicle families into 
subfamilies that include vehicles with identical FELs. Note that you 
may add subfamilies at any time during the model year.
    (c) Group vehicles into configurations consistent with the 
definition of ``vehicle configuration'' in Sec.  1037.801.

[[Page 57411]]

Note that vehicles with hardware or software differences that are 
related to measured or modeled emissions are considered to be different 
vehicle configurations even if they have the same GEM inputs and FEL. 
Note also, that you are not required to separately identify all 
configurations for certification. See paragraph (g) of this section for 
provisions allowing you to group certain hardware differences into the 
same configuration. Note that you are not required to identify all 
possible configurations for certification; also, you are required to 
include in your end-of year report only those configurations you 
produced.
    (d) For a vehicle model that straddles a roof-height, cab type, or 
GVWR division, you may include all the vehicles in the same vehicle 
family if you certify the vehicle family to the more stringent 
standards. For roof height, this means you must certify to the taller 
roof standards. For cab-type and GVWR, this means you must certify to 
the numerically lower standards.
    (e) [Reserved]
    (f) You may divide your families into more families than specified 
in this section.
    (g) You may ask us to allow you to group into the same 
configuration vehicles that have very small body hardware differences 
that do not significantly affect drag areas. Note that this allowance 
does not apply for substantial differences, even if the vehicles have 
the same measured drag areas.

Sec.  1037.241  Demonstrating compliance with exhaust emission 
standards for greenhouse gas pollutants.

    (a) For purposes of certification, your vehicle family is 
considered in compliance with the emission standards in Sec.  1037.105 
or Sec.  1037.106 if all vehicle configurations in that family have 
modeled CO2 emission rates (as specified in subpart F of 
this part) at or below the applicable standards. See 40 CFR part 86, 
subpart S, for showing compliance with the standards of Sec.  1037.104. 
Note that your FELs are considered to be the applicable emission 
standards with which you must comply if you participate in the ABT 
program in subpart H of this part.
    (b) Your vehicle family is deemed not to comply if any vehicle 
configuration in that family has a modeled CO2 emission rate 
that is above its FEL.
    (c) We may require you to provide an engineering analysis showing 
that the performance of your emission controls will not deteriorate 
during the useful life with proper maintenance. If we determine that 
your emission controls are likely to deteriorate during the useful 
life, we may require you to develop and apply deterioration factors 
consistent with good engineering judgment. For example, you may need to 
apply a deterioration factor to address deterioration of battery 
performance for an electric hybrid vehicle. Where the highest useful 
life emissions occur between the end of useful life and at the low-hour 
test point, base deterioration factors for the vehicles on the 
difference between (or ratio of) the point at which the highest 
emissions occur and the low-hour test point.

Sec.  1037.250  Reporting and recordkeeping.

    (a) Within 90 days after the end of the model year, send the 
Designated Compliance Officer a report including the total U.S.-
directed production volume of vehicles you produced in each vehicle 
family during the model year(based on information available at the time 
of the report). Report by vehicle identification number and vehicle 
configuration and identify the subfamily identifier. Report uncertified 
vehicles sold to secondary vehicle manufacturers. Small manufacturers 
may omit the reporting requirements of this paragraph (a).
    (b) Organize and maintain the following records:
    (1) A copy of all applications and any summary information you send 
us.
    (2) Any of the information we specify in Sec.  1037.205 that you 
were not required to include in your application.
    (3) A detailed history of each emission-data vehicle, if 
applicable.
    (4) Production figures for each vehicle family divided by assembly 
plant.
    (5) Keep a list of vehicle identification numbers for all the 
vehicles you produce under each certificate of conformity.
    (c) Keep routine data from emission tests required by this part 
(such as test cell temperatures and relative humidity readings) for one 
year after we issue the associated certificate of conformity. Keep all 
other information specified in this section for eight years after we 
issue your certificate.
    (d) Store these records in any format and on any media, as long as 
you can promptly send us organized, written records in English if we 
ask for them. You must keep these records readily available. We may 
review them at any time.

Sec.  1037.255  What decisions may EPA make regarding my certificate of 
conformity?

    (a) If we determine your application is complete and shows that the 
vehicle family meets all the requirements of this part and the Act, we 
will issue a certificate of conformity for your vehicle family for that 
model year. We may make the approval subject to additional conditions.
    (b) We may deny your application for certification if we determine 
that your vehicle family fails to comply with emission standards or 
other requirements of this part or the Clean Air Act. We will base our 
decision on all available information. If we deny your application, we 
will explain why in writing.
    (c) In addition, we may deny your application or suspend or revoke 
your certificate if you do any of the following:
    (1) Refuse to comply with any testing or reporting requirements.
    (2) Submit false or incomplete information (paragraph (e) of this 
section applies if this is fraudulent). This includes doing anything 
after submission of your application to render any of the submitted 
information false or incomplete.
    (3) Render any test data inaccurate.
    (4) Deny us from completing authorized activities despite our 
presenting a warrant or court order (see 40 CFR 1068.20). This includes 
a failure to provide reasonable assistance.
    (5) Produce vehicles for importation into the United States at a 
location where local law prohibits us from carrying out authorized 
activities.
    (6) Fail to supply requested information or amend your application 
to include all vehicles being produced.
    (7) Take any action that otherwise circumvents the intent of the 
Act or this part, with respect to your engine family.
    (d) We may void the certificate of conformity for a vehicle family 
if you fail to keep records, send reports, or give us information as 
required under this part or the Act. Note that these are also 
violations of 40 CFR 1068.101(a)(2).
    (e) We may void your certificate if we find that you intentionally 
submitted false or incomplete information. This includes rendering 
submitted information false or incomplete after submission.
    (f) If we deny your application or suspend, revoke, or void your 
certificate, you may ask for a hearing (see Sec.  1037.820).

Subpart D--[Reserved]

Subpart E--In-Use Testing

Sec.  1037.401  General provisions.

    We may perform in-use testing of any vehicle subject to the 
standards of this part. For example, we may test vehicles to verify 
drag areas or other GEM inputs.

[[Page 57412]]

Subpart F--Test and Modeling Procedures

Sec.  1037.501  General testing and modeling provisions.

    This subpart specifies how to perform emission testing and emission 
modeling required elsewhere in this part.
    (a) [Reserved]
    (b) Where exhaust emission testing is required, use the equipment 
and procedures in 40 CFR part 1066 to determine whether your vehicles 
meet the duty-cycle emission standards in subpart B of this part. 
Measure the emissions of all the exhaust constituents subject to 
emission standards as specified in 40 CFR part 1066. Use the applicable 
duty cycles specified in Sec.  1037.510.
    (c) [Reserved]
    (d) Use the applicable fuels specified 40 CFR part 1065 to perform 
valid tests.
    (1) For service accumulation, use the test fuel or any commercially 
available fuel that is representative of the fuel that in-use vehicles 
will use.
    (2) For diesel-fueled vehicles, use the appropriate diesel fuel 
specified for emission testing. Unless we specify otherwise, the 
appropriate diesel test fuel is ultra low-sulfur diesel fuel.
    (3) For gasoline-fueled vehicles, use the gasoline specified for 
``General Testing''.
    (e) You may use special or alternate procedures as specified in 40 
CFR 1065.10.
    (f) This subpart is addressed to you as a manufacturer, but it 
applies equally to anyone who does testing for you, and to us when we 
perform testing to determine if your vehicles meet emission standards.
    (g) Apply this paragraph (g) whenever we specify use of standard 
trailers. Unless otherwise specified, a tolerance of 2 
inches applies for all nominal trailer dimensions.
    (1) The standard trailer for high-roof tractors must meet the 
following criteria:
    (i) It is an unloaded two-axle dry van box trailer 53.0 feet long, 
102 inches wide, and 162 inches high (measured from the ground with the 
trailer level).
    (ii) It has a king pin located with its center 360.5 
inches from the front of the trailer and a minimized trailer gap (no 
greater than 45 inches).
    (iii) It has a smooth surface with nominally flush rivets and does 
not include any aerodynamic features such as side fairings, boat tails, 
or gap reducers. It may have a scuff band of no more than 0.13 inches 
in thickness.
    (iv) It includes dual 22.5 inch wheels, standard mudflaps, and 
standard landing gear. The centerline of the rear-most axle must be 146 
inches from the rear of the trailer.
    (2) The standard trailer for mid-roof tractors is an empty two-axle 
tanker trailer 421 feet long by 140 inches high.
    (i) It has a 401 feet long cylindrical tank with a 
70007 gallon capacity, smooth surface, and rounded ends.
    (ii) The standard tanker trailer does not include any aerodynamic 
features such as side fairings, but does include a centered 20 inch 
manhole, side-centered ladder, and lengthwise walkway. It includes dual 
24.5 inch wheels.
    (3) The standard trailer for low-roof tractors is an unloaded two-
axle flat bed trailer 531 feet long and 102 inches wide.
    (i) The deck height is 60.00.5 inches in the front and 
55.00.5 inches in the rear. The standard trailer does not 
include any aerodynamic features such as side fairings.
    (ii) It includes an air suspension and dual 22.5 inch wheels on 
tandem axles spread up to 122 inches apart between axle centerlines, 
measured along the length of the trailer.

Sec.  1037.510  Duty-cycle exhaust testing.

    This section applies where exhaust emission testing is required, 
such as when applying the provisions of Sec.  1037.615. Note that for 
most vehicles, testing under this section is not required.
    (a) Where applicable, measure emissions by testing the vehicle on a 
chassis dynamometer with the applicable test cycles. Each test cycle 
consists of a series of speed commands over time: variable speeds for 
the transient test and constant speeds for the cruise tests. None of 
these cycles include vehicle starting or warmup; each test cycle begins 
with a running, warmed-up vehicle. Start sampling emissions at the 
start of each cycle. The transient cycle is specified in Appendix I to 
this part. For the 55 mph and 65 mph cruise cycles, sample emissions 
for 300 second cycles with constant vehicle speeds of 55.0 mph and 65.0 
mph, respectively. The tolerance around these speed setpoints is 1.0 mph.
    (b) Calculate the official emission result from the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.011

Where:

payload = the standard payload, in tons, as specified in Sec.  
1037.705.
w = weighting factor for the appropriate test cycle, as described in 
paragraph (c) of this section.
m = grams of CO2 emitted over the appropriate test cycle.
D = miles driven over the appropriate test cycle.

    (c) Apply weighting factors specific to each type of vehicle and 
for each duty cycle as described in the following table:

                          Table 1 to Sec.   1037.510--Weighting Factors for Duty Cycles
----------------------------------------------------------------------------------------------------------------
                                                                                55 mph cruise     65 mph cruise
                                                             Transient  (%)          (%)               (%)
----------------------------------------------------------------------------------------------------------------
Vocational................................................                42                21                37
Vocational Hybrid Vehicles................................                75                 9                16
Day Cabs..................................................                19                17                64
Sleeper Cabs..............................................                 5                 9                86
----------------------------------------------------------------------------------------------------------------

[[Page 57413]]

     (d) For transient testing, compare actual second-by-second vehicle 
speed with the speed specified in the test cycle and ensure any 
differences are consistent with the criteria as specified in 40 CFR 
part 1066. If the speeds do not conform to these criteria, the test is 
not valid and must be repeated.
    (e) Run test cycles as specified in 40 CFR part 86. For cruise 
cycle testing of vehicles equipped with cruise control, use the 
vehicle's cruise control to control the vehicle speed. For vehicles 
equipped with adjustable VSLs, test the vehicle with the VSL at its 
highest setting.
    (f) Test the vehicle using its adjusted loaded vehicle weight, 
unless we determine this would be unrepresentative of in-use operation 
as specified in 40 CFR 1065.10(c)(1).
    (g) For hybrid vehicles, correct for the net energy change of the 
energy storage device as described in 40 CFR 1066.501.

Sec.  1037.520  Modeling CO2 emissions to show compliance.

    This section describes how to use the GEM simulation tool 
(incorporated by reference in Sec.  1037.810) to show compliance with 
the CO2 standards of Sec. Sec.  1037.105 and 1037.106. Use 
good engineering judgment when demonstrating compliance using the GEM.
    (a) General modeling provisions. To run the GEM, enter all 
applicable inputs as specified by the model. All seven of the following 
inputs apply for sleeper cab tractors, while some do not apply for 
other regulatory subcategories:
    (1) Regulatory subcategory (such as ``Class 8 Combination--Sleeper 
Cab--High Roof'').
    (2) Coefficient of aerodynamic drag, as described in paragraph (b) 
of this section. Leave this field blank for vocational vehicles.
    (3) Steer tire rolling resistance, as described in paragraph (c) of 
this section.
    (4) Drive tire rolling resistance, as described in paragraph (c) of 
this section.
    (5) Vehicle speed limit, as described in paragraph (d) of this 
section. Leave this field blank for vocational vehicles.
    (6) Vehicle weight reduction, as described in paragraph (e) of this 
section. Leave this field blank for vocational vehicles.
    (7) Extended idle reduction credit, as described in paragraph (f) 
of this section. Leave this field blank for vehicles other than Class 8 
sleeper cabs.
    (b) Coefficient of aerodynamic drag and drag area. Determine the 
appropriate drag area as follows:
    (1) Use the recommended method or an alternate method to establish 
a value for the vehicle's drag area, expressed in m\2\ and rounded to 
two decimal places. Where we allow you to group multiple configurations 
together, measure the drag area of the worst-case configuration. 
Measure drag areas specified in Sec.  1037.521.
    (2) Determine the bin level for your vehicle based on the drag area 
from paragraph (b)(1) of this section as shown in the following tables:

                           Table 1 to Sec.   1037.520--High-Roof Day and Sleeper Cabs
----------------------------------------------------------------------------------------------------------------
                                                               If your measured CDA    Then your CD input is . .
                         Bin level                               (m\2\) is . . .                   .
----------------------------------------------------------------------------------------------------------------
                                               High-Roof Day Cabs
----------------------------------------------------------------------------------------------------------------
Bin I.....................................................                     >= 8.0                       0.79
Bin II....................................................                    7.1-7.9                       0.72
Bin III...................................................                    6.2-7.0                       0.63
Bin IV....................................................                    5.6-6.1                       0.56
Bin V.....................................................                     = 7.6                       0.75
Bin II....................................................                    6.7-7.5                       0.68
Bin III...................................................                    5.8-6.6                       0.60
Bin IV....................................................                    5.2-5.7                       0.52
Bin V.....................................................                     = 5.1                       0.77
Bin II....................................................                     = 5.6                       0.87
Bin II....................................................                     2 minutes.
    (2) For each tire design tested, measure rolling resistance of at 
least three different tires of that specific design and size. Perform 
the test at least once for each tire. Use the arithmetic mean of these 
results as your test result. You may use this value as your GEM input 
or select a higher TRRL. You must test at least one tire size for each 
tire model, and may use engineering analysis to determine the rolling 
resistance of other tire sizes of that model. Note that for tire sizes 
that you do not test, we will treat your analytically derived rolling 
resistances the same as test results, and we may perform our own 
testing to verify your values. We may require you to test a small sub-
sample of untested tire sizes that we select.
    (3) If you obtain your test results from the tire manufacturer or 
another third party, you must obtain a signed statement from them 
verifying the tests were conducted according to the requirements of 
this part. Such statements are deemed to be submissions to EPA.
    (4) For tires marketed as light truck tires and that have load 
ranges C, D, or E, use as the GEM input TRRL at or above the measured 
rolling resistance multiplied by 0.87.
    (d) Vehicle speed limit. If the vehicles will be equipped with a 
vehicle speed limiter, input the maximum vehicle speed to which the 
vehicle will be limited (in miles per hour rounded to the nearest 0.1 
mile per hour) as specified in Sec.  1037.640. Otherwise leave this 
field blank. Use good engineering judgment to ensure the limiter is 
tamper resistant. We may require you to obtain preliminary approval for 
your designs.
    (e) Vehicle weight reduction. For purposes of this paragraph (e), 
high-strength steel is steel with tensile strength at or above 350 MPa.
    (1) Vehicle weight reduction inputs for wheels are specified 
relative to dual-wide tires with conventional steel wheels. For 
purposes of this paragraph (e)(1), a light-weight aluminum wheel is one 
that weighs at least 21 lb less than a comparable conventional steel 
wheel. The inputs are listed in Table 4 to this section. For example, a 
tractor with aluminum steel wheels and eight (4x2) dual-wide aluminum 
drive wheels would have an input of 210 lb (2x21 + 8x21).

       Table 3 to Sec.   1037.520--Wheel-Related Weight Reductions
------------------------------------------------------------------------
                                                              Weight
                                                          reduction  (lb
               Weight reduction technology                  per tire or
                                                              wheel)
------------------------------------------------------------------------
Single-Wide Drive Tire with
    Steel Wheel.........................................              84
    Aluminum Wheel......................................             139
    Light-Weight Aluminum Wheel.........................             147
Steer Tire or Dual-wide Drive Tire with . . .
    High-Strength Steel Wheel...........................               8
    Aluminum Wheel......................................              21
    Light-Weight Aluminum Wheel.........................              30
------------------------------------------------------------------------

    (2) Vehicle weight reduction inputs for components other than 
wheels are specified relative to mild steel components as specified in 
the following table:

     Table 4 to Sec.   1037.520--Nonwheel-Related Weight Reductions
------------------------------------------------------------------------
                                                         High-strength
  Weight reduction technologies     Aluminum weight      steel weight
                                    reduction (lb)      reduction (lb)
------------------------------------------------------------------------
Door............................                  20                   6
Roof............................                  60                  18
Cab rear wall...................                  49                  16
Cab floor.......................                  56                  18
Hood Support Structure System...                  15                   3
Fairing Support Structure System                  35                   6
Instrument Panel Support                           5                   1
 Structure......................
Brake Drums--Drive (4)..........                 140                  11
Brake Drums--Non Drive (2)......                  60                   8
Frame Rails.....................                 440                  87
Crossmember--Cab................                  15                   5
Crossmember--Suspension.........                  25                   6
Crossmember--Non Suspension (3).                  15                   5
Fifth Wheel.....................                 100                  25
Radiator Support................                  20                   6
Fuel Tank Support Structure.....                  40                  12
Steps...........................                  35                   6
Bumper..........................                  33                  10
Shackles........................                  10                   3
Front Axle......................                  60                  15
Suspension Brackets, Hangers....                 100                  30
Transmission Case...............                  50                  12
Clutch Housing..................                  40                  10
Drive Axle Hubs (8).............                 160                   4
Non Drive Front Hubs (2)........                  40                   5
Driveshaft......................                  20                   5
Transmission/Clutch Shift Levers                  20                   4
------------------------------------------------------------------------

[[Page 57415]]

     (3) You may ask to apply the innovative technology provisions of 
Sec.  1037.610 for weight reductions not covered by this paragraph (e).
    (f) Extended idle reduction credit. If your tractor is equipped 
with idle reduction technology meeting the requirements of Sec.  
1037.660 that will automatically shut off the main engine after 300 
seconds or less, use 5.0 g/ton-mile as the input (or a lesser value 
specified in Sec.  1037.660). Otherwise leave this field blank.

Sec.  1037.521  Aerodynamic measurements.

    This section describes how to determine the aerodynamic drag area 
(CDA) of your vehicle using the coastdown procedure in 40 
CFR part 1066 or an alternative method correlated to it.
    (a) General. The primary method for measuring the aerodynamic drag 
area of vehicles is specified in paragraph (b) of this section. You may 
determine the drag area using an alternate method, consistent with the 
provisions of this section and good engineering judgment, based on wind 
tunnel testing, computational fluid dynamic modeling, or constant-speed 
road load testing. See 40 CFR 1068.5 for provisions describing how we 
may evaluate your engineering judgment. All drag areas measured using 
an alternative method (CDAalt) must be adjusted 
to be equivalent to the corresponding drag areas that would have been 
measured using the coastdown procedure as follows:
    (1) Unless good engineering judgment requires otherwise, assume 
that coastdown drag areas are proportional to drag areas measured using 
alternative methods. This means you may apply a single constant 
adjustment factor (Falt-aero) for a given alternate drag 
area method using the following equation:

CDA = CDAalt x Falt-aero

    (2) Determine Falt-aero by performing coastdown testing 
and applying your alternate method on the same vehicle. Unless we 
approve another vehicle, the vehicle must be a Class 8, high-roof, 
sleeper cab with a full aerodynamics package, pulling a standards 
trailer. Where you have more than one model meeting these criteria, use 
the model with the highest projected sales. If you do not have such a 
model you may use your most comparable model with prior approval. If 
good engineering judgment allows the use of a single, constant value of 
Falt-aero, calculate it from this coastdown drag area 
(CDAcoast) divided by alternative drag area 
(CDAalt):

Falt-aero = CDAcoast / 
CDAalt

    (3) Calculate Falt-aero to at least three decimal 
places. For example, if your coastdown testing results in a drag area 
of 6.430, but your wind tunnel method results in a drag area of 6.200, 
Falt-aero would be 1.037.
    (b) Recommended method. Perform coastdown testing as described in 
40 CFR part 1066, subpart D, subject to the following additional 
provisions:
    (1) The specifications of this paragraph (b)(1) apply when 
measuring drag areas for tractors. Test high-roof tractors with a 
standard box trailer. Test low- and mid-roof tractors without a trailer 
(sometimes referred to as in a ``bobtail configuration''). You may test 
low- and mid-roof tractors with a trailer to evaluate innovative 
technologies.
    (2) The specifications of this paragraph (b)(2) apply for tractors 
and standard trailers. Use tires mounted on steel rims in a dual 
configuration (except for steer tires). The tires must--
    (i) Be SmartWay-Verified tires or have a rolling resistance below 
5.1 kg/ton.
    (ii) Have accumulated at least 2,175 miles of prior use but have no 
less than 50 percent of their original tread depth (as specified for 
truck cabs in SAE J1263).
    (iii) Not be retreads or have any apparent signs of chunking or 
uneven wear.
    (iv) Be size 295/75R22.5 or 275/80R22.5.
    (3) Calculate the drag area (CDA) in m\2\ from the 
coastdown procedure specified in 40 CFR part 1066.
    (c) Approval. You must obtain preliminary approval before using any 
methods other than coastdown testing to determine drag coefficients. 
Send your request for approval to the Designated Compliance Officer. 
Keep records of the information specified in this paragraph (c). Unless 
we specify otherwise, include this information with your request. You 
must provide any information we require to evaluate whether you are 
apply the provisions of this section consistent with good engineering 
judgment.
    (1) Include all of the following for your coastdown results:
    (i) The name, location, and description of your test facilities, 
including background/history, equipment and capability, and track and 
facility elevation, along with the grade and size/length of the track.
    (ii) Test conditions for each test result, including date and time, 
wind speed and direction, ambient temperature and humidity, vehicle 
speed, driving distance, manufacturer name, test vehicle/model type, 
model year, applicable model engine family, tire type and rolling 
resistance, weight of tractor-trailer (as tested), and driver 
identifier(s).
    (iii) Average drag area result as calculated in 40 CFR 1066, 
subpart D) and all of the individual run results (including voided or 
invalid runs).
    (2) Identify the name and location of the test facilities for your 
wind tunnel method (if applicable). Also include the following things 
to describe the test facility:
    (i) Background/history.
    (ii) The layout (with diagram), type, and construction (structural 
and material) of the wind tunnel.
    (iii) Wind tunnel design details: corner turning vane type and 
material, air settling, mesh screen specification, air straightening 
method, tunnel volume, surface area, average duct area, and circuit 
length.
    (iv) Wind tunnel flow quality: temperature control and uniformity, 
airflow quality, minimum airflow velocity, flow uniformity, angularity 
and stability, static pressure variation, turbulence intensity, airflow 
acceleration and deceleration times, test duration flow quality, and 
overall airflow quality achievement.
    (v) Test/working section information: test section type (e.g., 
open, closed, adaptive wall) and shape (e.g., circular, square, oval), 
length, contraction ratio, maximum air velocity, maximum dynamic 
pressure, nozzle width and height, plenum dimensions and net volume, 
maximum allowed model scale, maximum model height above road, strut 
movement rate (if applicable), model support, primary boundary layer 
slot, boundary layer elimination method, and photos and diagrams of the 
test section.
    (vi) Fan section description: fan type, diameter, power, maximum 
rotational speed, maximum top speed, support type, mechanical drive, 
and sectional total weight.
    (vii) Data acquisition and control (where applicable): acquisition 
type, motor control, tunnel control, model balance, model pressure 
measurement, wheel drag balances, wing/body panel balances, and model 
exhaust simulation.
    (viii) Moving ground plane or rolling road (if applicable): 
construction and material, yaw table and range, moving ground length 
and width, belt type, maximum belt speed, belt suction mechanism, 
platen instrumentation, temperature control, and steering.
    (ix) Facility correction factors and purpose.
    (3) Include all of the following for your computational fluid 
dynamics (CFD) method (if applicable):
    (i) Official name/title of the software product.

[[Page 57416]]

    (ii) Date and version number for the software product.
    (iii) Manufacturer/company name, address, phone number and Web 
address for software product.
    (iv) Identify if the software code is Navier-Stokes or Lattice-
Boltzmann based.
    (4) Include all of the following for any other method (if 
applicable):
    (i) Official name/title of the procedure(s).
    (ii) Description of the procedure.
    (iii) Cited sources for any standardized procedures that the method 
is based on.
    (iv) Modifications/deviations from the standardized procedures for 
the method and rational for modifications/deviations.
    (v) Data comparing this requested procedure to the coastdown 
reference procedure.
    (vi) Information above from the other methods as applicable to this 
method (e.g., source location/address, background/history).
    (d) Wind tunnel methods. (1) You may measure drag areas consistent 
with the modified SAE procedures described in this paragraph (d) using 
any wind tunnel recognized by the Subsonic Aerodynamic Testing 
Association. If your wind tunnel is not capable of testing in 
accordance with these modified SAE procedures, you may ask us to 
approve your alternate test procedures if you demonstrate that your 
procedures produce equivalent data. For purposes of this paragraph (d), 
data are equivalent if they are the same or better with respect to 
repeatability and unbiased correlation with coastdown testing. Note 
that, for wind tunnels not capable of these modified SAE procedures, 
good engineering judgment may require you to base your alternate method 
adjustment factor on more than one vehicle. You may not develop your 
correction factor until we have approved your alternate method. The 
applicable SAE procedures are SAE J1252, SAE J1594, and SAE J2071 
(incorporated by reference in Sec.  1037.810). The following 
modifications apply for SAE J1252:
    (i) The minimum Reynold's number (Remin) is 1.0 x 10\6\ 
instead of the value specified in section 5.2 of the SAE procedure. 
Your model frontal area at zero yaw angle may exceed the recommended 5 
percent of the active test section area, provided it does not exceed 25 
percent.
    (ii) For full-scale wind tunnel testing, use good engineering 
judgment to select a test article (tractor and trailer) that is a 
reasonable representation of the test article used for the reference 
method testing. For example, where your wind tunnel is not long enough 
to test the tractor with a standard 53 foot trailer, it may be 
appropriate to use shorter box trailer. In such a case, the correlation 
developed using the shorter trailer would only be valid for testing 
with the shorter trailer.
    (iii) For reduced-scale wind tunnel testing, a one-eighth (1/8th) 
or larger scale model of a heavy-duty tractor and trailer must be used, 
and the model must be of sufficient design to simulate airflow through 
the radiator inlet grill and across an engine geometry representative 
of those commonly used in your test vehicle.
    (2) You must perform wind tunnel testing and the coastdown 
procedure on the same tractor model and provide the results for both 
methods. Conduct the wind tunnel tests at a zero yaw angle and, if so 
equipped, utilizing the moving/rolling floor (i.e., the moving/rolling 
floor should be on during the test, as opposed to static) for 
comparison to the coastdown procedure, which corrects to a zero yaw 
angle for the oncoming wind.
    (e) Computational fluid dynamics (CFD). You may determine drag 
areas using a CFD method, consistent with good engineering judgment and 
the requirements of this paragraph (e) using commercially available CFD 
software code. Conduct the analysis assuming zero yaw angle, and 
ambient conditions consistent with coastdown procedures. For simulating 
a wind tunnel test, the analysis should accurately model the particular 
wind tunnel and assume a wind tunnel blockage ratio consistent with SAE 
J1252 (incorporated by reference in Sec.  1037.810) or one that matches 
the selected wind tunnel, whichever is lower. For simulation of open 
road conditions similar to that experienced during coastdown test 
procedures, the CFD analysis should assume a blockage ratio at or below 
0.2 percent.
    (1) Take the following steps for CFD code with a Navier-Stokes 
formula solver:
    (i) Perform an unstructured, time-accurate, analysis using a mesh 
grid size with total volume element count of at least 50 million cells 
of hexahedral and/or polyhedral mesh cell shape, surface elements 
representing the geometry consisting of no less than 6 million 
elements, and a near-wall cell size corresponding to a y+ value of less 
than 300, with the smallest cell sizes applied to local regions of the 
tractor and trailer in areas of high flow gradients and smaller 
geometry features.
    (ii) Perform the analysis with a turbulence model and mesh 
deformation enabled (if applicable) with boundary layer resolution of 
95 percent. Once result convergence is achieved, 
demonstrate the convergence by supplying multiple, successive 
convergence values for the analysis. The turbulence model may use k-
epsilon (k-[egr]), shear stress transport k-omega (SST k-[omega]), or 
other commercially accepted methods.
    (2) For Lattice-Boltzman based CFD code, perform an unstructured, 
time-accurate analysis using a mesh grid size with total surface 
elements of at least 50 million cells using cubic volume elements and 
triangular and/or quadrilateral surface elements with a near wall cell 
size of no greater than 6 mm on local regions of the tractor and 
trailer in areas of high flow gradients and smaller geometry features, 
with cell sizes in other areas of the mesh grid starting at twelve 
millimeters and increasing in size from this value as the distance from 
the tractor-trailer model increases.
    (3) All CFD analysis should be conducted using the following 
conditions:
    (i) A tractor-trailer combination using the manufacturer's tractor 
and the standard trailer, as applicable.
    (ii) An environment with a blockage ratio at or below 0.2 percent 
to simulate open road conditions, a zero degree yaw angle between the 
oncoming wind and the tractor-trailer combination.
    (iii) Ambient conditions consistent with the coastdown test 
procedures specified in this part.
    (iv) Open grill with representative back pressures based on data 
from the tractor model,
    (v) Turbulence model and mesh deformation enabled (if applicable).
    (vi) Tires and ground plane in motion consistent with and 
simulating a vehicle moving in the forward direction of travel.
    (vii) The smallest cell size should be applied to local regions on 
the tractor and trailer in areas of high flow gradients and smaller 
geometry features (e.g., the a-pillar, mirror, visor, grille and 
accessories, trailer leading and trailing edges, rear bogey, tires, and 
tractor-trailer gap).
    (viii) Simulate a speed of 55 mph.
    (4) You may ask us to allow you to perform CFD analysis using 
parameters and criteria other than those specified in this paragraph 
(e), consistent with good engineering judgment, if you can demonstrate 
that the specified conditions are not feasible (e.g., insufficient 
computing power to conduct such analysis, inordinate length of time to 
conduct analysis, equivalent flow characteristics with more feasible

[[Page 57417]]

criteria/parameters) or improved criteria may yield better results 
(e.g., different mesh cell shape and size). To support this request, we 
may require that you supply data demonstrating that your selected 
parameters/criteria will provide a sufficient level of detail to yield 
an accurate analysis, including comparison of key characteristics 
between your criteria/parameters and the criteria specified in 
paragraphs (e)(1) and (2) of this section (e.g., pressure profiles, 
drag build-up, and/or turbulent/laminar flow at key points on the front 
of the tractor and/or over the length of the tractor-trailer 
combination).
    (f) Yaw sweep corrections. You may optionally apply this paragraph 
(f) for vehicles with aerodynamic features that are more effective at 
reducing wind-averaged drag than is predicted by zero-yaw drag. You may 
correct your zero-yaw drag area as follows if the ratio of the zero-yaw 
drag area divided by yaw sweep drag area for your vehicle is greater 
than 0.8065 (which represents the ratio expected for a typical 
aerodynamic Class 8 high-roof sleeper cab tractor):
    (1) Determine the zero-yaw drag area and the yaw sweep drag area 
for your vehicle using the same alternate method as specified in this 
subpart. Measure drag area for 0[deg], -6[deg], and +6[deg]. Use the 
arithmetic mean of the -6[deg] and +6[deg] drag areas as the 6[deg] drag area.
    (2) Calculate your yaw sweep correction factor (CFys) 
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.012

    (3) Calculate your corrected drag area for determining the 
aerodynamic bin by multiplying the measured zero-yaw drag area by 
CFys. The correction factor may be applied to drag areas 
measured using other procedures. For example, we would apply 
CFys to drag areas measured using the recommended coastdown 
method. If you use an alternative method, you would also need to apply 
an alternative correction (Falt-aero) and calculate the 
final drag area using the following equation:

    CDA = Falt-aero [middot] CFys 
[middot] (CDA)zero-alt

    (4) You may ask us to apply CFys to similar vehicles 
incorporating the same design features.
    (5) As an alternative, you may choose to calculate the wind-
averaged drag area according to SAE J1252 (incorporated by reference in 
Sec.  1037.810) and substitute this value into the equation in 
paragraph (f)(2) of this section for the 6[deg] yaw-
averaged drag area.

Sec.  1037.525  Special procedures for testing hybrid vehicles with 
power take-off.

    This section describes the procedure for quantifying the reduction 
in greenhouse gas emissions as a result of running power take-off (PTO) 
devices with a hybrid powertrain. The procedures are written to test 
the PTO so that all the energy is produced with the engine. The full 
test for the hybrid vehicle is from a fully charged renewable energy 
storage system (RESS) to a depleted RESS and then back to a fully 
charged RESS. These procedures may be used for whole vehicles or with a 
post-transmission hybrid system. When testing just the post-
transmission hybrid system, you must include all hardware for the PTO 
system. You may ask us to modify the provisions of this section to 
allow testing hybrid vehicles other than electric-battery hybrids, 
consistent with good engineering judgment.
    (a) Select two vehicles for testing as follows:
    (1) Select a vehicle with a hybrid powertrain to represent the 
vehicle family. If your vehicle family includes more than one vehicle 
model, use good engineering judgment to select the vehicle type with 
the maximum number of PTO circuits that has the smallest potential 
reduction in greenhouse gas emissions.
    (2) Select an equivalent conventional vehicle as specified in Sec.  
1037.615.
    (b) Measure PTO emissions from the fully warmed-up conventional 
vehicle as follows:
    (1) Without adding any additional restrictions, instrument the 
vehicle with pressure transducers at the outlet of the hydraulic pump 
for each circuit.
    (2) Operate the PTO system with no load for at least 15 seconds. 
Measure the pressure and record the average value over the last 10 
seconds (pmin). Apply maximum operator demand to the PTO 
system until the pressure relief valve opens and pressure stabilizes; 
measure the pressure and record the average value over the last 10 
seconds (pmax).
    (3) Denormalize the PTO duty cycle in Appendix II of this part 
using the following equation:

prefi = NPi [middot] (pmax-
min) + pmin

Where:

    prefi = the reference pressure at each point i in the 
PTO cycle.
    NPi= the normalized pressure at each point i in the 
PTO cycle.
    pmax= the maximum pressure measured in paragraph 
(b)(2) of this section.
    pmin= the minimum pressure measured in paragraph 
(b)(2) of this section.

    (4) If the PTO system has two circuits, repeat paragraph (b)(2) and 
(3) of this section for the second PTO circuit.
    (5) Install a system to control pressures in the PTO system during 
the cycle.
    (6) Start the engine.
    (7) Operate the vehicle over one or both of the denormalized PTO 
duty cycles, as applicable. Collect CO2 emissions during 
operation over each duty cycle.
    (8) Use the provisions of 40 CFR part 1066 to collect and measure 
emissions. Calculate emission rates in grams per test without rounding.
    (9) For each test, validate the pressure in each circuit with the 
pressure specified from the cycle according to 40 CFR 1065.514. 
Measured pressures must meet the specifications in the following table 
for a valid test:

                   Table 1 of Sec.   1037.525--Statistical Criteria for Validating Duty Cycles
----------------------------------------------------------------------------------------------------------------
                  Parameter                                                Pressure
----------------------------------------------------------------------------------------------------------------
Slope, [verbar]a1[verbar]...................  0.950 = 0.970.
----------------------------------------------------------------------------------------------------------------

[[Page 57418]]

    (10) Continue testing over the three vehicle drive cycles, as 
otherwise required by this part.
    (11) Calculate combined cycle-weighted emissions of the four cycles 
as specified in paragraph (d) of this section.
    (c) Measure PTO emissions from the fully warmed-up hybrid vehicle 
as follows:
    (1) Perform the steps in paragraphs (b)(1) through (5) of this 
section.
    (2) Prepare the vehicle for testing by operating it as needed to 
stabilize the battery at a full state of charge. For electric hybrid 
vehicles, we recommend running back-to-back PTO tests until engine 
operation is initiated to charge the battery. The battery should be 
fully charged once engine operation stops. The ignition should remain 
in the ``on'' position.
    (3) Turn the vehicle and PTO system off while the sampling system 
is being prepared.
    (4) Turn the vehicle and PTO system on such that the PTO system is 
functional, whether it draws power from the engine or a battery.
    (5) Operate the vehicle over the PTO cycle(s) without turning the 
vehicle off, until the engine starts and then shuts down. The test 
cycle is completed once the engine shuts down. Measure emissions as 
described in paragraphs (b)(2) and (3) of this section. Use good 
engineering judgment to minimize the variability in testing between the 
two types of vehicles.
    (6) Refer to paragraph (b)(9) of this section for cycle validation.
    (7) Continue testing over the three vehicle drive cycles, as 
otherwise required by this part.
    (8) Calculate combined cycle-weighted emissions of the four cycles 
as specified in paragraph (d) of this section.
    (d) Calculate combined cycle-weighted emissions of the four cycles 
for vocational vehicles as follows:
    (1) Calculate the g/ton-mile emission rate for the driving portion 
of the test specified in Sec.  1037.510.
    (2) Calculate the g/hr emission rate for the PTO portion of the 
test by dividing the total mass emitted over the cycle (grams) by the 
time of the test (hours). For testing where fractions of a cycle were 
run (for example, where three cycles are completed and the halfway 
point of a fourth PTO cycle is reached before the engine starts and 
shuts down again), use the following procedures to calculate the time 
of the test:
    (i) Add up the time run for all complete tests.
    (ii) For fractions of a test, use the following equation to 
calculate the time:
[GRAPHIC] [TIFF OMITTED] TR15SE11.013

Where:
ttest = time of the incomplete test.
i = the number of each measurement interval.
N = the total number of measurement intervals.
NPcircuit--1 = Normalized pressure command from circuit 1 
of the PTO cycle.
NPcircuit--2 = Normalized pressure command from circuit 2 
of the PTO cycle. Let NPcircuit--2 = 1 if there is only 
one circuit.
tcycle = time of a complete cycle.

    (iii) Sum the time from complete cycles (paragraph (d)(2)(i) of 
this section) and from partial cycles (paragraph (d)(2)(ii) of this 
section).
    (3) Convert the g/hr PTO result to an equivalent g/mi value based 
on the assumed fraction of engine operating time during which the PTO 
is operating (28 percent) and an assumed average vehicle speed while 
driving (27.1 mph). The conversion factor is: Factor = (0.280)/(1.000-
0.280)/(27.1 mph) = 0.0144 hr/mi. Multiply the g/hr emission rate by 
0.0144 hr/mi.
    (4) Divide the g/mi PTO emission rate by the standard payload and 
add this value to the g/ton-mile emission rate for the driving portion 
of the test.
    (e) Follow the provisions of Sec.  1037.615 to calculate 
improvement factors and benefits for advanced technologies.

Sec.  1037.550  Special procedures for testing post-transmission hybrid 
systems.

    This section describes the procedure for simulating a chassis test 
with a post-transmission hybrid system for A to B testing. The hardware 
that must be included in these tests is the engine, the transmission, 
the hybrid electric motor, the power electronics between the hybrid 
electric motor and the RESS, and the RESS. You may ask us to modify the 
provisions of this section to allow testing non-electric hybrid 
vehicles, consistent with good engineering judgment.
    (a) Set up the engine according to 40 CFR 1065.110 to account for 
work inputs and outputs and accessory work.
    (b) Collect CO2 emissions while operating the system 
over the test cycles specified in Sec.  1037.510.
    (c) Collect and measure emissions as described in 40 CFR part 1066. 
Calculate emission rates in grams per ton-mile without rounding. 
Determine values for A, B, C, and M for the vehicle being simulated as 
specified in 40 CFR part 1066. If you will apply an improvement factor 
or test results to multiple vehicle configurations, use values of A, B, 
C, M, kd, and r that represent the vehicle configuration 
with the smallest potential reduction in greenhouse gas emissions as a 
result of the hybrid capability.
    (d) Calculate the transmission output shaft's angular speed target 
for the driver model, fnref,driver, from the linear speed 
associated with the vehicle cycle using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.014

Where:
Scyclei = vehicle speed of the test cycle for each point 
i.
kd = final drive ratio (the angular speed of the 
transmission output shaft divided by the angular speed of the drive 
axle), as declared by the manufacturer.
r = radius of the loaded tires, as declared by the manufacturer.

    (e) Use either speed control or torque control to program the 
dynamometer to follow the test cycle, as follows:
    (1) Speed control. Program dynamometers using speed control as 
described in this paragraph (e)(1). We recommend speed control for 
automated manual transmissions or other designs where there is a power 
interrupt during shifts. Calculate the transmission output shaft's 
angular speed target for the dynamometer, fnref,dyno, from 
the measured linear speed at the dynamometer rolls using the following 
equation:

[[Page 57419]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.015

Where:
[GRAPHIC] [TIFF OMITTED] TR15SE11.016

t = elapsed time in the driving schedule as measured by the 
dynamometer, in seconds.
Let ti-1 = 0.
[GRAPHIC] [TIFF OMITTED] TR15SE11.017

Where:
Ti = instantaneous measured torque at the transmission 
output shaft.
fn,i = instantaneous measured angular speed of the 
transmission output shaft.

    (2) Torque control. Program dynamometers using torque control as 
described in this paragraph (e)(2).
    (i) Calculate the transmission output shaft's torque target, 
Trefi, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.018

Where:
FRi = total road load force at the surface of the roll, 
calculated using the equation in 40 CFR 1066.210(d)(4), as specified 
in paragraph (e)(2)(ii) of this section.

    (ii) Calculate the total road load force based on instantaneous 
speed values, Si, calculated from the equation in paragraph 
(e)(1) of this section.
    (3) For each test, validate the measured transmission output 
shaft's speed or torque with the corresponding reference values 
according to 40 CFR 1065.514(e). You may delete points when the vehicle 
is braking or stopped. Perform the validation based on speed and torque 
values at the transmission output shaft. For steady-state tests (55 mph 
and 65 mph cruise), apply cycle-validation criteria by treating the 
sampling periods from the two tests as a continuous sampling period. 
Perform this validation based on the following parameters for either 
speed-control or torque-control, as applicable:

  Table 1 of Sec.   1037.550--Statistical Criteria for Validating Duty
                                 Cycles
------------------------------------------------------------------------
          Parameter               Speed control        Torque control
------------------------------------------------------------------------
Slope, a1...................  0.950 =0.970...  =0.850.
 determination, r \2\.
------------------------------------------------------------------------

     (f) Send a brake signal when throttle position is equal to zero 
and vehicle speed is greater than the reference vehicle speed from the 
test cycle. The brake signal should be turned off when the torque 
measured at the transmission output shaft is less than the reference 
torque. Set a delay before changing the brake state using good 
engineering judgment to prevent the brake signal from dithering.
    (g) The driver model should be designed to follow the cycle as 
closely as possible and must meet the requirements of 40 CFR 
1066.430(e) for transient testing and Sec.  1037.510 for steady-state 
testing.
    (h) Correct for the net energy change of the energy storage device 
as described in 40 CFR 1066.501.
    (i) Follow the provisions of Sec.  1037.510 to weight the cycle 
results and Sec.  1037.615 to calculate improvement factors and 
benefits for advanced technologies.

Subpart G--Special Compliance Provisions

Sec.  1037.601  What compliance provisions apply to these vehicles?

    (a) Engine and vehicle manufacturers, as well as owners and 
operators of vehicles subject to the requirements of this part, and all 
other persons, must observe the provisions of this part, the provisions 
of the Clean Air Act, and the following provisions of 40 CFR part 1068:
    (1) The exemption and importation provisions of 40 CFR part 1068, 
subparts C and D, apply for vehicles subject to this part 1037, except 
that the hardship exemption provisions of 40 CFR 1068.245, 1068.250, 
and 1068.255 do not apply for motor vehicles.
    (2) Manufacturers may comply with the defect reporting requirements 
of 40 CFR 1068.501 instead of the defect reporting requirements of 40 
CFR part 85.
    (b) Vehicles exempted from the applicable standards of 40 CFR part 
86 are exempt from the standards of this part without request. 
Similarly, vehicles are exempt without request if the installed engine 
is exempted from the applicable standards in 40 CFR part 86.
    (c) The prohibitions of 40 CFR 86.1854 apply for vehicles subject 
to the requirements of this part. The actions prohibited under this 
provision include the introduction into U.S. commerce of a complete or 
incomplete vehicle subject to the standards of this part where the 
vehicle is not covered by a valid certificate of conformity or 
exemption.
    (d) Except as specifically allowed by this part, it is a violation 
of section 203(a)(1) of the Clean Air Act (42 U.S.C. 7522(a)(1)) to 
introduce into U.S. commerce a tractor containing an engine not 
certified for use in tractors; or to introduce into U.S. commerce a 
vocational vehicle containing a light heavy-duty or medium heavy-duty 
engine not certified for use in vocational vehicles. This prohibition 
applies especially to the vehicle manufacturer.
    (e) A vehicle manufacturer that completes assembly of a vehicle at 
two or more facilities may ask to use as the date of manufacture for 
that vehicle the date on which manufacturing is completed at the place 
of main assembly, consistent with provisions of

[[Page 57420]]

49 CFR 567.4. Note that such staged assembly is subject to the 
provisions of 40 CFR 1068.260(c). Include your request in your 
application for certification, along with a summary of your staged-
assembly process. You may ask to apply this allowance to some or all of 
the vehicles in your vehicle family. Our approval is effective when we 
grant your certificate. We will not approve your request if we 
determine that you intend to use this allowance to circumvent the 
intent of this part.

Sec.  1037.610  Vehicles with innovative technologies.

    (a) You may ask us to apply the provisions of this section for 
CO2 emission reductions resulting from vehicle technologies 
that were not in common use with heavy-duty vehicles before model year 
2010 that are not reflected in the GEM simulation tool. These 
provisions may be applied for CO2 emission reductions 
reflected using the specified test procedures, provided they are not 
reflected in the GEM. We will apply these provisions only for 
technologies that will result in measurable, demonstrable, and 
verifiable real-world CO2 emission reductions.
    (b) The provisions of this section may be applied as either an 
improvement factor or as a separate credit, consistent with good 
engineering judgment. We recommend that you base your credit/adjustment 
on A to B testing of pairs of vehicles differing only with respect to 
the technology in question.
    (1) Calculate improvement factors as the ratio of in-use emissions 
with the technology divided by the in-use emissions without the 
technology. Use the improvement-factor approach where good engineering 
judgment indicates that the actual benefit will be proportional to 
emissions measured over the test procedures specified in this part.
    (2) Calculate separate credits (g/ton-mile) based on the difference 
between the in-use emission rate with the technology and the in-use 
emission rate without the technology. Multiply this difference by the 
number of vehicles, standard payload, and useful life. Use the 
separate-credit approach where good engineering judgment indicates that 
the actual benefit will be not be proportional to emissions measured 
over the test procedures specified in this part.
    (3) We may require you to discount or otherwise adjust your 
improvement factor or credit to account for uncertainty or other 
relevant factors.
    (c) You may perform A to B testing by measuring emissions from the 
vehicles during chassis testing or from in-use on-road testing. We 
recommend that you perform on-road testing according to SAE J1321 Joint 
TMC/SAE Fuel Consumption Test Procedure Type II Reaffirmed 1986-10 or 
SAE J1526 Joint TMC/SAE Fuel Consumption In-Service Test Procedure Type 
III Issued 1987-06 (see Sec.  1037.810 for information availability of 
SAE standards), subject to the following provisions:
    (1) The minimum route distance is 100 miles.
    (2) The route selected must be representative in terms of grade. We 
will take into account published and relevant research in determining 
whether the grade is representative.
    (3) The vehicle speed over the route must be representative of the 
drive-cycle weighting adopted for each regulatory subcategory. For 
example, if the route selected for an evaluation of a combination 
tractor with a sleeper cab contains only interstate driving, the 
improvement factor would apply only to 86 percent of the weighted 
result.
    (4) The ambient air temperature must be between 5 and 35[deg]C, 
unless the technology requires other temperatures for demonstration.
    (5) We may allow you to use a Portable Emissions Measurement System 
(PEMS) device for measuring CO2 emissions during the on-road 
testing.
    (d) Send your request to the Designated Compliance Officer. Include 
a detailed description of the technology and a recommended test plan. 
Also state whether you recommend applying these provisions using the 
improvement-factor method or the separate-credit method. We recommend 
that you do not begin collecting test data (for submission to EPA) 
before contacting us. For technologies for which the engine 
manufacturer could also claim credits (such as transmissions in certain 
circumstances), we may require you to include a letter from the engine 
manufacturer stating that it will not seek credits for the same 
technology.
    (e) We may seek public comment on your request, consistent with the 
provisions of 40 CFR 86.1866. However, we will generally not seek 
public comment on credits or adjustments based on A to B chassis 
testing performed according to the duty-cycle testing requirements of 
this part or in-use testing performed according to paragraph (c) of 
this section.

Sec.  1037.615  Hybrid vehicles and other advanced technologies.

    (a) This section applies for hybrid vehicles with regenerative 
braking, vehicles equipped with Rankine-cycle engines, electric 
vehicles, and fuel cell vehicles. You may not generate credits for 
engine features for which the engines generate credits under 40 CFR 
part 1036.
    (b) Generate advanced technology emission credits for hybrid 
vehicles that include regenerative braking (or the equivalent) and 
energy storage systems, fuel cell vehicles, and vehicles equipped with 
Rankine-cycle engines as follows:
    (1) Measure the effectiveness of the advanced system by chassis 
testing a vehicle equipped with the advanced system and an equivalent 
conventional vehicle. Test the vehicles as specified in subpart F of 
this part. For purposes of this paragraph (b), a conventional vehicle 
is considered to be equivalent if it has the same footprint (as defined 
in 40 CFR 86.1803), vehicle service class, aerodynamic drag, and other 
relevant factors not directly related to the hybrid powertrain. If you 
use Sec.  1037.525 to quantify the benefits of a hybrid system for PTO 
operation, the conventional vehicle must have same number of PTO 
circuits and have equivalent PTO power. If you do not produce an 
equivalent vehicle, you may create and test a prototype equivalent 
vehicle. The conventional vehicle is considered Vehicle A and the 
advanced vehicle is considered Vehicle B. We may specify an alternate 
cycle if your vehicle includes a power take-off.
    (2) Calculate an improvement factor and g/ton-mile benefit using 
the following equations and parameters:
    (i) Improvement Factor = [(Emission Rate A)--(Emission Rate B)]/
(Emission Rate A)
    (ii) g/ton-mile benefit = Improvement Factor x (GEM Result B)
    (iii) Emission Rates A and B are the g/ton-mile CO2 
emission rates of the conventional and advanced vehicles, respectively, 
as measured under the test procedures specified in this section. GEM 
Result B is the g/ton-mile CO2 emission rate resulting from 
emission modeling of the advanced vehicle as specified in Sec.  
1037.520.
    (3) Use the equations of Sec.  1037.705 to convert the g/ton-mile 
benefit to emission credits (in Mg). Use the g/ton-mile benefit in 
place of the (Std-FEL) term.
    (c) See Sec.  1037.525 for special testing provisions related to 
hybrid vehicles equipped with power take-off units.
    (d) You may use an engineering analysis to calculate an improvement 
factor for fuel cell vehicles based on measured emissions from the fuel 
cell vehicle.
    (e) For electric vehicles, calculate CO2 credits using 
an FEL of 0 g/ton-mile.

[[Page 57421]]

    (f) As specified in subpart H of this part, credits generated under 
this section may be used under this part 1037 outside of the averaging 
set in which they were generated or used under 40 CFR part 1036.
    (g) You may certify using both provisions of this section and the 
innovative technology provisions of Sec.  1037.610, provided you do not 
double count emission benefits.

Sec.  1037.620  Shipment of incomplete vehicles to secondary vehicle 
manufacturers.

    This section specifies how manufacturers may introduce partially 
complete vehicles into U.S. commerce.
    (a) The provisions of this section allow manufacturers to ship 
partially complete vehicles to secondary vehicle manufacturers or 
otherwise introduce them into U.S. commerce in the following 
circumstances:
    (1) Tractors. Manufacturers may introduce partially complete 
tractors into U.S. commerce if they are covered by a certificate of 
conformity for tractors and will be in their certified tractor 
configuration before they reach the ultimate purchasers. For example, 
this would apply for sleepers initially shipped without the sleeper 
compartments attached. Note that delegated assembly provisions may 
apply (see 40 CFR 1068.261).
    (2) Vocational vehicles. Manufacturers may introduce partially 
complete vocational vehicles into U.S. commerce if they are covered by 
a certificate of conformity for vocational vehicles and will be in 
their certified vocational configuration before they reach the ultimate 
purchasers. Note that delegated assembly provisions may apply (see 40 
CFR 1068.261).
    (3) Uncertified vehicles that will be certified by secondary 
vehicle manufacturers. Manufacturers may introduce into U.S. commerce 
partially complete vehicles for which they do not hold a certificate of 
conformity only as allowed by paragraph (b) of this section.
    (b) The provisions of this paragraph (b) generally apply where the 
secondary vehicle manufacturer has substantial control over the design 
and assembly of emission controls. In determining whether a 
manufacturer has substantial control over the design and assembly of 
emission controls, we would consider the degree to which the secondary 
manufacturer would be able to ensure that the engine and vehicle will 
conform to the regulations in their final configurations.
    (1) A secondary manufacturer may finish assembly of partially 
complete vehicles in the following cases:
    (i) It obtains a vehicle that is not fully assembled with the 
intent to manufacture a complete vehicle in a certified configuration.
    (ii) It obtains a vehicle with the intent to modify it to a 
certified configuration before it reaches the ultimate purchaser. For 
example, this may apply for converting a gasoline-fueled vehicle to 
operate on natural gas under the terms of a valid certificate.
    (2) Manufacturers may introduce partially complete vehicles into 
U.S. commerce as described in this paragraph (b) if they have a written 
request for such vehicles from a secondary vehicle manufacturer that 
will finish the vehicle assembly and has certified the vehicle (or the 
vehicle has been exempted or excluded from the requirements of this 
part). The written request must include a statement that the secondary 
manufacturer has a certificate of conformity (or exemption/exclusion) 
for the vehicle and identify a valid vehicle family name associated 
with each vehicle model ordered (or the basis for an exemption/
exclusion). The original vehicle manufacturer must apply a removable 
label meeting the requirements of 40 CFR 1068.45 that identifies the 
corporate name of the original manufacturer and states that the vehicle 
is exempt under the provisions of Sec.  1037.620. The name of the 
certifying manufacturer must also be on the label or, alternatively, on 
the bill of lading that accompanies the vehicles during shipment. The 
original manufacturer may not apply a permanent emission control 
information label identifying the vehicle's eventual status as a 
certified vehicle.
    (3) If you are the secondary manufacturer and you will hold the 
certificate, you must include the following information in your 
application for certification:
    (i) Identify the original manufacturer of the partially complete 
vehicle or of the complete vehicle you will modify.
    (ii) Describe briefly how and where final assembly will be 
completed. Specify how you have the ability to ensure that the vehicles 
will conform to the regulations in their final configuration. (Note: 
This section prohibits using the provisions of this paragraph (b) 
unless you have substantial control over the design and assembly of 
emission controls.)
    (iii) State unconditionally that you will not distribute the 
vehicles without conforming to all applicable regulations.
    (4) If you are a secondary manufacturer and you are already a 
certificate holder for other families, you may receive shipment of 
partially complete vehicles after you apply for a certificate of 
conformity but before the certificate's effective date. This exemption 
allows the original manufacturer to ship vehicles after you have 
applied for a certificate of conformity. Manufacturers may introduce 
partially complete vehicles into U.S. commerce as described in this 
paragraph (b)(4) if they have a written request for such vehicles from 
a secondary manufacturer stating that the application for certification 
has been submitted (instead of the information we specify in paragraph 
(b)(2) of this section). We may set additional conditions under this 
paragraph (b)(4) to prevent circumvention of regulatory requirements.
    (5) Both original and secondary manufacturers must keep the records 
described in this section for at least five years, including the 
written request for exempted vehicles and the bill of lading for each 
shipment (if applicable). The written request is deemed to be a 
submission to EPA.
    (6) These provisions are intended only to allow secondary 
manufacturers to obtain or transport vehicles in the specific 
circumstances identified in this section so any exemption under this 
section expires when the vehicle reaches the point of final assembly 
identified in paragraph (b)(3)(ii) of this section.
    (7) For purposes of this section, an allowance to introduce 
partially complete vehicles into U.S. commerce includes a conditional 
allowance to sell, introduce, or deliver such vehicles into commerce in 
the United States or import them into the United States. It does not 
include a general allowance to offer such vehicles for sale because 
this exemption is intended to apply only for cases in which the 
certificate holder already has an arrangement to purchase the vehicles 
from the original manufacturer. This exemption does not allow the 
original manufacturer to subsequently offer the vehicles for sale to a 
different manufacturer who will hold the certificate unless that second 
manufacturer has also complied with the requirements of this part. The 
exemption does not apply for any individual vehicles that are not 
labeled as specified in this section or which are shipped to someone 
who is not a certificate holder.
    (8) We may suspend, revoke, or void an exemption under this 
section, as follows:
    (i) We may suspend or revoke your exemption if you fail to meet the 
requirements of this section. We may suspend or revoke an exemption 
related to a specific secondary manufacturer if that manufacturer sells 
vehicles that are

[[Page 57422]]

in not in a certified configuration in violation of the regulations. We 
may disallow this exemption for future shipments to the affected 
secondary manufacturer or set additional conditions to ensure that 
vehicles will be assembled in the certified configuration.
    (ii) We may void an exemption for all the affected vehicles if you 
intentionally submit false or incomplete information or fail to keep 
and provide to EPA the records required by this section.
    (iii) The exemption is void for a vehicle that is shipped to a 
company that is not a certificate holder or for a vehicle that is 
shipped to a secondary manufacturer that is not in compliance with the 
requirements of this section.
    (iv) The secondary manufacturer may be liable for penalties for 
causing a prohibited act where the exemption is voided due to actions 
on the part of the secondary manufacturer.
    (c) Provide instructions along with partially complete vehicles 
including all information necessary to ensure that an engine will be 
installed in its certified configuration.

Sec.  1037.630  Special purpose tractors.

    (a) General provisions. This section allows a vehicle manufacturer 
to reclassify certain tractors as vocational tractors. Vocational 
tractors are treated as vocational vehicles and are exempt from the 
standards of Sec.  1037.106. Note that references to ``tractors'' 
outside of this section mean non-vocational tractors.
    (1) This allowance is intended only for vehicles that do not 
typically operate at highway speeds, or would otherwise not benefit 
from efficiency improvements designed for line-haul tractors. This 
allowance is limited to the following vehicle and application types:
    (i) Low-roof tractors intended for intra-city pickup and delivery, 
such as those that deliver bottled beverages to retail stores.
    (ii) Tractors intended for off-road operation (including mixed 
service operation), such as those with reinforced frames and increased 
ground clearance.
    (iii) Tractors with a GCWR over 120,000 pounds.
    (2) Where we determine that a manufacturer is not applying this 
allowance in good faith, we may require the manufacturer to obtain 
preliminary approval before using this allowance.
    (b) Requirements. The following requirements apply with respect to 
tractors reclassified under this section:
    (1) The vehicle must fully conform to all requirements applicable 
to vocational vehicles under this part.
    (2) Vehicles reclassified under this section must be certified as a 
separate vehicle family. However, they remain part of the vocational 
regulatory sub-category and averaging set that applies for their weight 
class.
    (3) You must include the following additional statement on the 
vehicle's emission control information label under Sec.  1037.135: 
``THIS VEHICLE WAS CERTIFIED AS A VOCATIONAL TRACTOR UNDER 40 CFR 
1037.630.''.
    (4) You must keep records for three years to document your basis 
for believing the vehicles will be used as described in paragraph 
(a)(1) of this section. Include in your application for certification a 
brief description of your basis.
    (c) Production limit. No manufacturer may produce more than 21,000 
vehicles under this section in any consecutive three model year period. 
This means you may not exceed 6,000 in a given model year if the 
combined total for the previous two years was 15,000. The production 
limit applies with respect to all Class 7 and Class 8 tractors 
certified or exempted as vocational tractors. Note that in most cases, 
the provisions of paragraph (a) of this section will limit the 
allowable number of vehicles to be a number lower than the production 
limit of this paragraph (c).
    (d) Off-road exemption. All the provisions of this section apply 
for vocational tractors exempted under Sec.  1037.631, except as 
follows:
    (1) The vehicles are required to comply with the requirements of 
Sec.  1037.631 instead of the requirements that would otherwise apply 
to vocational vehicles. Vehicles complying with the requirements of 
Sec.  1037.631 and using an engine certified to the standards of 40 CFR 
part 1036 are deemed to fully conform to all requirements applicable to 
vocational vehicles under this part.
    (2) The vehicles must be labeled as specified under Sec.  1037.631 
instead of as specified in paragraph (b)(3) of this section.

Sec.  1037.631  Exemption for vocational vehicles intended for off-road 
use.

    This section provides an exemption from the greenhouse gas 
standards of this part for certain vocational vehicles intended to be 
used extensively in off-road environments such as forests, oil fields, 
and construction sites. This section does not exempt the engine used in 
the vehicle from the standards of 40 CFR part 86 or part 1036. Note 
that you may not include these exempted vehicles in any credit 
calculations under this part.
    (a) Qualifying criteria. Vocational vehicles intended for off-road 
use meeting either the criteria of paragraph (a)(1) or (a)(2) of this 
section are exempt without request, subject to the provisions of this 
section.
    (1) Vehicles are exempt if the tires installed on the vehicle have 
a maximum speed rating at or below 55 mph.
    (2) Vehicles are exempt if they were primarily designed to perform 
work off-road (such as in oil fields, forests, or construction sites), 
and they meet at least one of the criteria of paragraph (a)(2)(i) of 
this section and at least one of the criteria of paragraph (a)(2)(ii) 
of this section.
    (i) The vehicle must have affixed components designed to work in an 
off-road environment (i.e., hazardous material equipment or off-road 
drill equipment) or be designed to operate at low speeds such that it 
is unsuitable for normal highway operation.
    (ii) The vehicle must meet one of the following criteria:
    (A) Have an axle that has a gross axle weight rating (GAWR) of 
29,000 pounds.
    (B) Have a speed attainable in 2 miles of not more than 33 mph.
    (C) Have a speed attainable in 2 miles of not more than 45 mph, an 
unloaded vehicle weight that is not less than 95 percent of its gross 
vehicle weight rating (GVWR), and no capacity to carry occupants other 
than the driver and operating crew.
    (b) Tractors. The provisions of this section may apply for tractors 
only if each tractor qualifies as a vocational tractor under Sec.  
1037.630.
    (c) Recordkeeping and reporting. (1) You must keep records to 
document that your exempted vehicle configurations meet all applicable 
requirements of this section. Keep these records for at least eight 
years after you stop producing the exempted vehicle model. We may 
review these records at any time.
    (2) You must also keep records of the individual exempted vehicles 
you produce, including the vehicle identification number and a 
description of the vehicle configuration.
    (3) Within 90 days after the end of each model year, you must send 
to the Designated Compliance Officer a report with the following 
information:
    (i) A description of each exempted vehicle configuration, including 
an explanation of why it qualifies for this exemption.
    (ii) The number of vehicles exempted for each vehicle 
configuration.
    (d) Labeling. You must include the following additional statement 
on the vehicle's emission control information label under Sec.  
1037.135: ``THIS VEHICLE

[[Page 57423]]

WAS EXEMPTED UNDER 40 CFR 1037.631.''.

Sec.  1037.640  Variable vehicle speed limiters.

    This section specifies provisions that apply for vehicle speed 
limiters (VSLs) that you model under Sec.  1037.520. This does not 
apply for VSLs that you do not model under Sec.  1037.520.
    (a) General. The regulations of this part do not constrain how you 
may design VSLs for your vehicles. For example, you may design your VSL 
to have a single fixed speed limit or a soft-top speed limit. You may 
also design your VSL to expire after accumulation of a predetermined 
number of miles. However, designs with soft tops or expiration features 
are subject to proration provisions under this section that do not 
apply to fixed VSLs that do not expire.
    (b) Definitions. The following definitions apply for purposes of 
this section:
    (1) Default speed limit means the speed limit that normally applies 
for the vehicle, except as follows:
    (i) The default speed limit for adjustable VSLs must represent the 
speed limit that applies when the VSL is adjusted to its highest 
setting under paragraph (c) of this section.
    (ii) For VSLs with soft tops, the default speed does not include 
speeds possible only during soft-top operation.
    (iii) For expiring VSLs, the default does not include speeds that 
are possible only after expiration.
    (2) Soft-top speed limit means the highest speed limit that applies 
during soft-top operation.
    (3) Maximum soft-top duration means the maximum amount of time that 
a vehicle could operate above the default speed limit.
    (4) Certified VSL means a VSL configuration that applies when a 
vehicle is new and until it expires.
    (5) Expiration point means the mileage at which a vehicle's 
certified VSL expires (or the point at which tamper protections 
expire).
    (6) Effective speed limit has the meaning given in paragraph (d) of 
this section.
    (c) Adjustments. You may design your VSL to be adjustable; however, 
this may affect the value you use in the GEM.
    (1) Except as specified in paragraph (c)(2) of this section, any 
adjustments that can be made to the engine, vehicle, or their controls 
that change the VSL's actual speed limit are considered to be 
adjustable operating parameters. Compliance is based on the vehicle 
being adjusted to the highest speed limit within this range.
    (2) The following adjustments are not adjustable parameters:
    (i) Adjustments made only to account for changing tire size or 
final drive ratio.
    (ii) Adjustments protected by encrypted controls or passwords.
    (iii) Adjustments possible only after the VSL's expiration point.
    (d) Effective speed limit. (1) For VSLs without soft tops or 
expiration points that expire before 1,259,000 miles, the effective 
speed limit is the highest speed limit that results by adjusting the 
VSL or other vehicle parameters consistent with the provisions of 
paragraph (c) of this section.
    (2) For VSLs with soft tops and/or expiration points, the effective 
speed limit is calculated as specified in this paragraph (d)(2), which 
is based on 10 hours of operation per day (394 miles per day for day 
cabs and 551 miles per day for sleeper cabs). Note that this 
calculation assumes that a fraction of this operation is speed limited 
(3.9 hours and 252 miles for day cabs, and 7.3 hours and 474 miles for 
sleeper cabs). Use the following equation to calculate the effective 
speed limit, rounded to the nearest 0.1 mph:

Effective speed = ExF * [STF* STSL + (1-STF) * DSL] + (1-ExF)*65 mph

Where:

ExF = expiration point miles/1,259,000 miles
STF = maximum number of allowable soft top operation hours per day/
3.9 hours for day cabs (or maximum miles per day/252)
STF = maximum number of allowable soft top operation hours per day/
7.3 hours for sleeper cabs (or maximum miles per day/474)
STSL = the soft top speed limit
DSL = the default speed limit

Sec.  1037.645  In-use compliance with family emission limits (FELs).

    You may ask us to apply a higher in-use FEL for certain in-use 
vehicles, subject to the provisions of this section. Note that Sec.  
1037.225 contains provisions related to changing FELs during a model 
year.
    (a) Purpose. This section is intended to address circumstances in 
which it is in the public interest to apply a higher in-use FEL based 
on forfeiting an appropriate number of emission credits.
    (b) FELs. We may apply higher in-use FELs to your vehicles as 
follows:
    (1) Where your vehicle family includes more than one sub-family 
with different FELs, we may apply a higher FEL within the family than 
was applied to the vehicle's configuration in your final ABT report. 
For example, if your vehicle family included three sub-families with 
FELs of 200 g/ton-mile, 210 g/ton-mile, and 220 g/ton-mile, we may 
apply a 220 g/ton-mile in-use FEL to vehicles that were originally 
designated as part of the 200 g/ton-mile or 210 g/ton-mile sub-
families.
    (2) Without regard to the number of sub-families in your certified 
vehicle family, we may specify new sub-families with higher FELs than 
were included in your final ABT report. We may apply these higher FELs 
as in-use FELs for your vehicles. For example, if your vehicle family 
included three sub-families with FELs of 200 g/ton-mile, 210 g/ton-
mile, and 220 g/ton-mile, we may specify a new 230 g/ton-mile sub-
family.
    (3) In specifying sub-families and in-use FELs, we would intend to 
accurately reflect the actual in-use performance of your vehicles, 
consistent with the specified testing and modeling provisions of this 
part.
    (c) Equivalent families. We may apply the higher FELs to other 
families in other model years if they used equivalent emission 
controls.
    (d) Credit forfeiture. Where we specify higher in-use FELs under 
this section, you must forfeit CO2 emission credits based on 
the difference between the in-use FEL and the otherwise applicable FEL. 
Calculate the amount of credits to be forfeited using the applicable 
equation in Sec.  1037.705, by substituting the otherwise applicable 
FEL for the standard and the in-use FEL for the otherwise applicable 
FEL.
    (e) Requests. Submit your request to the Designated Compliance 
Officer. Include the following in your request:
    (1) The vehicle family name, model year, and name/description of 
the configuration(s) affected.
    (2) A list of other vehicle families/configurations/model years 
that may be affected.
    (3) The otherwise applicable FEL for each configuration along with 
your recommendations for higher in-use FELs.
    (4) Your source of credits for forfeiture.
    (f) Relation to recall. You may not request higher in-use FELs for 
any vehicle families for which we have made a determination of 
nonconformance and ordered a recall. You may, however, make such 
requests for vehicle families for which you are performing a voluntary 
emission recall.
    (g) Approval. We may approve your request if we determine that you 
meet the requirements of this section and such approval is in the 
public interest. We may include appropriate conditions with our 
approval or we may approve your request with modifications.

Sec.  1037.650  Tire manufacturers.

    This section describes how the requirements of this part apply with

[[Page 57424]]

respect to tire manufacturers that choose to provide test data or 
emission warranties for purposes of this part.
    (a) Testing. You are responsible as follows for test tires and 
emission test results that you provide to vehicle manufacturers for the 
purpose of the manufacturer submitting them to EPA for certification 
under this part:
    (1) Such test results are deemed under Sec.  1037.825 to be 
submissions to EPA. This means that you may be subject to criminal 
penalties under 18 U.S.C. 1001 if you knowingly submit false test 
results to the manufacturer.
    (2) You may not cause a vehicle manufacturer to violate the 
regulations by rendering inaccurate emission test results you provide 
(or emission test results from testing of test tires you provide) to 
the vehicle manufacturer.
    (3) Your provision of test tires and emission test results to 
vehicle manufacturers for the purpose of certifying under this part is 
deemed to be an agreement to provide tires to EPA for confirmatory 
testing under Sec.  1037.201.
    (b) Warranty. You may contractually agree to process emission 
warranty claims on behalf of the manufacturer certifying the vehicle 
with respect to tires you produce.
    (1) Your fulfillment of the warranty requirements of this part is 
deemed to fulfill the vehicle manufacturer's warranty obligations under 
this part with respect to tires you warrant.
    (2) You may not cause a vehicle manufacturer to violate the 
regulations by failing to fulfill the emission warranty requirements 
that you contractually agreed to fulfill.

Sec.  1037.655  Post-useful life vehicle modifications.

    This section specifies vehicle modifications that may occur after a 
vehicle reaches the end of its regulatory useful life. It does not 
apply with respect to modifications that occur within the useful life 
period. It also does not apply with respect to engine modifications or 
recalibrations. Note that many such modifications to the vehicle during 
the useful life and to the engine at any time are presumed to violate 
42 U.S.C. 7522(a)(3)(A).
    (a) General. Except as allowed by this section, it is prohibited 
for any person to remove or render inoperative any emission control 
device installed to comply with the requirements of this part 1037.
    (b) Allowable modifications. You may modify a vehicle for the 
purpose of reducing emissions, provided you have a reasonable technical 
basis for knowing that such modification will not increase emissions of 
any other pollutant. Reasonable technical basis has the meaning given 
in 40 CFR 1068.30. This generally requires you to have information that 
would lead an engineer or other person familiar with engine and vehicle 
design and function to reasonably believe that the modifications will 
not increase emissions of any regulated pollutant.
    (c) Examples of allowable modifications. The following are examples 
of allowable modifications:
    (1) It is generally allowable to remove tractor roof fairings after 
the end of the vehicle's useful life if the vehicle will no longer be 
used primarily to pull box trailers.
    (2) Other fairings may be removed after the end of the vehicle's 
useful life if the vehicle will no longer be used significantly on 
highways with vehicle speed of 55 miles per hour or higher.
    (d) Examples of prohibited modifications. The following are 
examples of modifications that are not allowable:
    (1) No person may disable a vehicle speed limiter prior to its 
expiration point.
    (2) No person may remove aerodynamic fairings from tractors that 
are used primarily to pull box trailers on highways.

Sec.  1037.660  Automatic engine shutdown systems.

    This section specifies requirements that apply for certified 
automatic engine shutdown systems (AES) that are modeled under Sec.  
1037.520. It does not apply for AES systems that you do not model under 
Sec.  1037.520.
    (a) Minimum requirements. Your AES system must meet all of the 
requirements of this paragraph (a) to be modeled under Sec.  1037.520. 
The system must shut down the engine within 300 seconds when all the 
following conditions are met:
    (1) The transmission is set in neutral with the parking brake 
engaged (or the transmission is set to park if so equipped).
    (2) The operator has not reset the system timer within the 300 
seconds by changing the position of the accelerator, brake, or clutch 
pedal; or by some other mechanism we approve.
    (3) None of the override conditions of paragraph (b) of this 
section are met.
    (b) Override conditions. The system may delay shutting the engine 
down while any of the conditions of this paragraph (b) apply. Engines 
equipped with auto restart may restart during override conditions. Note 
that these conditions allow the system to delay shutdown or restart, 
but do not allow it to reset the timer. The system may delay shutdown--
    (1) While an exhaust emission control device is regenerating. The 
period considered to be regeneration for purposes of this allowance 
must be consistent with good engineering judgment and may differ in 
length from the period considered to be regeneration for other 
purposes. For example, in some cases it may be appropriate to include a 
cool down period for this purpose but not for infrequent regeneration 
adjustment factors.
    (2) If necessary while servicing the vehicle, provided the 
deactivation of the AES system is accomplished using a diagnostic scan 
tool. The system must be automatically reactivated when the engine is 
shutdown for more than 60 minutes.
    (3) If the vehicle's main battery state-of-charge is not sufficient 
to allow the main engine to be restarted.
    (4) If the external ambient temperature reaches a level below which 
or above which the cabin temperature cannot be maintained within 
reasonable heat or cold exposure threshold limit values for the health 
and safety of the operator (not merely comfort).
    (5) If the vehicle's engine coolant temperature is too low 
according to the manufacturer's engine protection guidance. This may 
also apply for fuel or oil temperatures. This allows the engine to 
continue operating until it reaches a predefined temperature at which 
the shutdown sequence of paragraph (a) of this section would resume.
    (6) The system may delay shutdown while the vehicle's main engine 
is operating in power take-off (PTO) mode. For purposes of this 
paragraph (b)(6), an engine is considered to be in PTO mode when a 
switch or setting designating PTO mode is enabled.
    (c) Expiration of AES systems. The AES system may include an 
expiration point (in miles) after which the AES system may be disabled. 
If your vehicle is equipped with an expiring AES system that expires 
before 1,259,000 miles adjust the model input as follows:

Input = 5 g CO2/ton-mile x (miles at expiration/1,259,000 
miles)

    (d) Adjustable parameters. Provisions that apply generally with 
respect to adjustable parameters also apply to the AES system operating 
parameters, except the following are not considered to be adjustable 
parameters:
    (1) Accelerator, brake, and clutch pedals, with respect to 
resetting the idle timer. Parameters associated with other timer reset 
mechanisms we approve are also not adjustable parameters.

[[Page 57425]]

    (2) Bypass parameters allowed for vehicle service under paragraph 
(b)(2) of this section.
    (3) Parameters that are adjustable only after the expiration point.

Subpart H--Averaging, Banking, and Trading for Certification

Sec.  1037.701  General provisions.

    (a) You may average, bank, and trade (ABT) emission credits for 
purposes of certification as described in this subpart and in subpart B 
of this part to show compliance with the standards of Sec. Sec.  
1037.105 and 1037.106. Participation in this program is voluntary.
    (b) The definitions of Subpart I of this part apply to this 
subpart. The following definitions also apply:
    (1) Actual emission credits means emission credits you have 
generated that we have verified by reviewing your final report.
    (2) Averaging set means a set of vehicles in which emission credits 
may be exchanged. Credits generated by one vehicle may only be used by 
other vehicles in the same averaging set. Note that an averaging set 
may comprise more than one regulatory subcategory. See Sec.  1037.740.
    (3) Broker means any entity that facilitates a trade of emission 
credits between a buyer and seller.
    (4) Buyer means the entity that receives emission credits as a 
result of a trade.
    (5) Reserved emission credits means emission credits you have 
generated that we have not yet verified by reviewing your final report.
    (6) Seller means `the entity that provides emission credits during 
a trade.
    (7) Standard means the emission standard that applies under subpart 
B of this part for vehicles not participating in the ABT program of 
this subpart.
    (8) Trade means to exchange emission credits, either as a buyer or 
seller.
    (c) Emission credits may be exchanged only within an averaging set 
as specified in Sec.  1037.740.
    (d) You may not use emission credits generated under this subpart 
to offset any emissions that exceed an FEL or standard, except as 
allowed by Sec.  1037.645.
    (e) You may trade emission credits generated from any number of 
your vehicles to the vehicle purchasers or other parties to retire the 
credits. Identify any such credits in the reports described in Sec.  
1037.730. Vehicles must comply with the applicable FELs even if you 
donate or sell the corresponding emission credits under this paragraph 
(e). Those credits may no longer be used by anyone to demonstrate 
compliance with any EPA emission standards.
    (f) Emission credits may be used in the model year they are 
generated. Surplus emission credits may be banked for future model 
years. Surplus emission credits may sometimes be used for past model 
years, as described in Sec.  1037.745.
    (g) You may increase or decrease an FEL during the model year by 
amending your application for certification under Sec.  1037.225. The 
new FEL may apply only to vehicles you have not already introduced into 
commerce.
    (h) See Sec.  1037.740 for special credit provisions that apply for 
credits generated under Sec.  1037.104(d)(7), Sec.  1037.615 or 40 CFR 
1036.615.
    (i) Unless the regulations explicitly allow it, you may not 
calculate credits more than once for any emission reduction. For 
example, if you generate CO2 emission credits for a given 
hybrid vehicle under this part, no one may generate CO2 
emission credits for the hybrid engine under 40 CFR part 1036. However, 
credits could be generated for identical engine used in vehicles that 
did not generate credits under this part.

Sec.  1037.705  Generating and calculating emission credits.

    (a) The provisions of this section apply separately for calculating 
emission credits for each pollutant.
    (b) For each participating family or subfamily, calculate positive 
or negative emission credits relative to the otherwise applicable 
emission standard. Calculate positive emission credits for a family or 
subfamily that has an FEL below the standard. Calculate negative 
emission credits for a family or subfamily that has an FEL above the 
standard. Sum your positive and negative credits for the model year 
before rounding. Round the sum of emission credits to the nearest 
megagram (Mg), using consistent units throughout the following 
equations:
    (1) For vocational vehicles:

Emission credits (Mg) = (Std-FEL) x (Payload Tons) x (Volume) x (UL) x 
(10-6)

Where:

Std = the emission standard associated with the specific tractor 
regulatory subcategory (g/ton-mile).
FEL = the family emission limit for the vehicle subfamily (g/ton-
mile).
Payload tons = the prescribed payload for each class in tons (2.85 
tons for light heavy-duty vehicles, 5.6 tons for medium heavy-duty 
vehicles, and 7.5 tons for heavy heavy-duty vehicles).
Volume = U.S.-directed production volume of the vehicle subfamily. 
For example, if you produce three configurations with the same FEL, 
the subfamily production volume would be the sum of the production 
volumes for these three configurations.
UL = useful life of the vehicle (110,000 miles for light heavy-duty 
vehicles, 185,000 miles for medium heavy-duty vehicles, and 435,000 
miles for heavy heavy-duty vehicles).

    (2) For tractors:

Emission credits (Mg) = (Std-FEL) x (Payload tons) x (Volume) x (UL) x 
(10-6)

Where:

Std = the emission standard associated with the specific tractor 
regulatory subcategory (g/ton-mile).
FEL = the family emission limit for the vehicle subfamily (g/ton-
mile).
Payload tons = the prescribed payload for each class in tons (12.5 
tons for Class 7 and 19 tons for Class 8).
Volume = U.S.-directed production volume of the vehicle subfamily.
UL = useful life of the tractor (435,000 miles for Class 8 and 
185,000 miles for Class 7).

    (c) As described in Sec.  1037.730, compliance with the 
requirements of this subpart is determined at the end of the model year 
based on actual U.S.-directed production volumes. Keep appropriate 
records to document these production volumes. Do not include any of the 
following vehicles to calculate emission credits:
    (1) Vehicles that you do not certify to the CO2 
standards of this part because they are permanently exempted under 
subpart G of this part or under 40 CFR part 1068.
    (2) Exported vehicles.
    (3) Vehicles not subject to the requirements of this part, such as 
those excluded under Sec.  1037.5.
    (4) Any other vehicles, where we indicate elsewhere in this part 
1037 that they are not to be included in the calculations of this 
subpart.

Sec.  1037.710  Averaging.

    (a) Averaging is the exchange of emission credits among your 
vehicle families. You may average emission credits only within the same 
averaging set.
    (b) You may certify one or more vehicle families (or subfamilies) 
to an FEL above the applicable standard, subject to any applicable FEL 
caps and other provisions in subpart B of this part, if you show in 
your application for certification that your projected balance of all 
emission-credit transactions in that model year is greater than or 
equal to zero or that a negative balance is allowed under Sec.  
1037.745.
    (c) If you certify a vehicle family to an FEL that exceeds the 
otherwise applicable standard, you must obtain

[[Page 57426]]

enough emission credits to offset the vehicle family's deficit by the 
due date for the final report required in Sec.  1037.730. The emission 
credits used to address the deficit may come from your other vehicle 
families that generate emission credits in the same model year (or from 
later model years as specified in Sec.  1037.745), from emission 
credits you have banked, or from emission credits you obtain through 
trading.

Sec.  1037.715  Banking.

    (a) Banking is the retention of surplus emission credits by the 
manufacturer generating the emission credits for use in future model 
years for averaging or trading.
    (b) You may designate any emission credits you plan to bank in the 
reports you submit under Sec.  1037.730 as reserved credits. During the 
model year and before the due date for the final report, you may 
designate your reserved emission credits for averaging or trading.
    (c) Reserved credits become actual emission credits when you submit 
your final report. However, we may revoke these emission credits if we 
are unable to verify them after reviewing your reports or auditing your 
records.
    (d) Banked credits retain the designation of the averaging set in 
which they were generated.

Sec.  1037.720  Trading.

    (a) Trading is the exchange of emission credits between 
manufacturers, or the transfer of credits to another party to retire 
them. You may use traded emission credits for averaging, banking, or 
further trading transactions. Traded emission credits remain subject to 
the averaging-set restrictions based on the averaging set in which they 
were generated.
    (b) You may trade actual emission credits as described in this 
subpart. You may also trade reserved emission credits, but we may 
revoke these emission credits based on our review of your records or 
reports or those of the company with which you traded emission credits. 
You may trade banked credits within an averaging set to any certifying 
manufacturer.
    (c) If a negative emission credit balance results from a 
transaction, both the buyer and seller are liable, except in cases we 
deem to involve fraud. See Sec.  1037.255(e) for cases involving fraud. 
We may void the certificates of all vehicle families participating in a 
trade that results in a manufacturer having a negative balance of 
emission credits. See Sec.  1037.745.

Sec.  1037.725  What must I include in my application for 
certification?

    (a) You must declare in your application for certification your 
intent to use the provisions of this subpart for each vehicle family 
that will be certified using the ABT program. You must also declare the 
FELs you select for the vehicle family or subfamily for each pollutant 
for which you are using the ABT program. Your FELs must comply with the 
specifications of subpart B of this part, including the FEL caps. FELs 
must be expressed to the same number of decimal places as the 
applicable standards.
    (b) Include the following in your application for certification:
    (1) A statement that, to the best of your belief, you will not have 
a negative balance of emission credits for any averaging set when all 
emission credits are calculated at the end of the year; or a statement 
that you will have a negative balance of emission credits for one or 
more averaging sets but that it is allowed under Sec.  1037.745.
    (2) Calculations of projected emission credits (positive or 
negative) based on projected U.S.-directed production volumes. We may 
require you to include similar calculations from your other vehicle 
families to project your net credit balances for the model year. If you 
project negative emission credits for a family or subfamily, state the 
source of positive emission credits you expect to use to offset the 
negative emission credits.

Sec.  1037.730  ABT reports.

    (a) If any of your vehicle families are certified using the ABT 
provisions of this subpart, you must send an end-of-year report within 
90 days after the end of the model year and a final report within 270 
days after the end of the model year.
    (b) Your end-of-year and final reports must include the following 
information for each vehicle family participating in the ABT program:
    (1) Vehicle-family and subfamily designations.
    (2) The regulatory subcategory and emission standards that would 
otherwise apply to the vehicle family.
    (3) The FEL for each pollutant. If you change the FEL after the 
start of production, identify the date that you started using the new 
FEL and/or give the vehicle identification number for the first vehicle 
covered by the new FEL. In this case, identify each applicable FEL and 
calculate the positive or negative emission credits as specified in 
Sec.  1037.225.
    (4) The projected and actual U.S.-directed production volumes for 
the model year. If you changed an FEL during the model year, identify 
the actual production volume associated with each FEL.
    (5) Useful life.
    (6) Calculated positive or negative emission credits for the whole 
vehicle family. Identify any emission credits that you traded, as 
described in paragraph (d)(1) of this section.
    (7) If you have a negative credit balance for the averaging set in 
the given model year, specify whether the vehicle family (or certain 
subfamilies with the vehicle family) have a credit deficit for the 
year. Consider for example, a manufacturer with three vehicle families 
(``A'', ``B'', and ``C'') in a given averaging set. If family A 
generates enough credits to offset the negative credits of family B but 
not enough to also offset the negative credits of family C (and the 
manufacturer has no banked credits in the averaging set), the 
manufacturer may designate families A and B as having no deficit for 
the model year, provided it designates family C as having a deficit for 
the model year.
    (c) Your end-of-year and final reports must include the following 
additional information:
    (1) Show that your net balance of emission credits from all your 
participating vehicle families in each averaging set in the applicable 
model year is not negative, except as allowed under Sec.  1037.745.
    (2) State whether you will reserve any emission credits for 
banking.
    (3) State that the report's contents are accurate.
    (d) If you trade emission credits, you must send us a report within 
90 days after the transaction, as follows:
    (1) As the seller, you must include the following information in 
your report:
    (i) The corporate names of the buyer and any brokers.
    (ii) A copy of any contracts related to the trade.
    (iii) The vehicle families that generated emission credits for the 
trade, including the number of emission credits from each family.
    (2) As the buyer, you must include the following information in 
your report:
    (i) The corporate names of the seller and any brokers.
    (ii) A copy of any contracts related to the trade.
    (iii) How you intend to use the emission credits, including the 
number of emission credits you intend to apply to each vehicle family 
(if known).
    (e) Send your reports electronically to the Designated Compliance 
Officer using an approved information format. If you want to use a 
different format,

[[Page 57427]]

send us a written request with justification for a waiver.
    (f) Correct errors in your end-of-year report or final report as 
follows:
    (1) You may correct any errors in your end-of-year report when you 
prepare the final report, as long as you send us the final report by 
the time it is due.
    (2) If you or we determine within 270 days after the end of the 
model year that errors mistakenly decreased your balance of emission 
credits, you may correct the errors and recalculate the balance of 
emission credits. You may not make these corrections for errors that 
are determined more than 270 days after the end of the model year. If 
you report a negative balance of emission credits, we may disallow 
corrections under this paragraph (f)(2).
    (3) If you or we determine anytime that errors mistakenly increased 
your balance of emission credits, you must correct the errors and 
recalculate the balance of emission credits.

Sec.  1037.735  Recordkeeping.

    (a) You must organize and maintain your records as described in 
this section. We may review your records at any time.
    (b) Keep the records required by this section for at least eight 
years after the due date for the end-of-year report. You may not use 
emission credits for any vehicles if you do not keep all the records 
required under this section. You must therefore keep these records to 
continue to bank valid credits. Store these records in any format and 
on any media, as long as you can promptly send us organized, written 
records in English if we ask for them. You must keep these records 
readily available. We may review them at any time.
    (c) Keep a copy of the reports we require in Sec. Sec.  1037.725 
and 1037.730.
    (d) Keep records of the vehicle identification number for each 
vehicle you produce that generates or uses emission credits under the 
ABT program. You may identify these numbers as a range. If you change 
the FEL after the start of production, identify the date you started 
using each FEL and the range of vehicle identification numbers 
associated with each FEL. You must also identify the purchaser and 
destination for each vehicle you produce to the extent this information 
is available.
    (e) We may require you to keep additional records or to send us 
relevant information not required by this section in accordance with 
the Clean Air Act.

Sec.  1037.740  Restrictions for using emission credits.

    The following restrictions apply for using emission credits:
    (a) Averaging sets. Except as specified in paragraph (b) of this 
section, emission credits may be exchanged only within an averaging 
set. There are three principal averaging sets for vehicles subject to 
this subpart.
    (1) Vehicles at or below 19,500 pounds GVWR that are subject to the 
standards of Sec.  1037.105.
    (2) Vehicles above 19,500 pounds GVWR but at or below 33,000 pounds 
GVWR.
    (3) Vehicles over 33,000 pounds GVWR.
    (4) Note that other separate averaging sets also apply for emission 
credits not related to this subpart. For example, under Sec.  1037.104, 
an additional averaging set comprises all vehicles subject to the 
standards of that section. Separate averaging sets also apply for 
engines under 40 CFR part 1036, including engines used in vehicles 
subject to this subpart.
    (b) Credits from hybrid vehicles and other advanced technologies. 
The averaging set restrictions of paragraph (a) of this section do not 
apply for credits generated under Sec.  1037.104(d)(7), Sec.  1037.615 
or 40 CFR 1036.615 from hybrid vehicles with regenerative braking, or 
from other advanced technologies.
    (1) The maximum amount of credits you may bring into the following 
service class groups is 60,000 Mg per model year:
    (i) Spark-ignition engines, light heavy-duty compression-ignition 
engines, and light heavy-duty vehicles. This group comprises the 
averaging set listed in paragraphs (a)(1) of this section and the 
averaging set listed in 40 CFR 1036.740(a)(1) and (2).
    (ii) Medium heavy-duty compression-ignition engines and medium 
heavy-duty vehicles. This group comprises the averaging sets listed in 
paragraph (a)(2) of this section and 40 CFR 1036.740(a)(3).
    (iii) Heavy heavy-duty compression-ignition engines and heavy 
heavy-duty vehicles. This group comprises the averaging sets listed in 
paragraph (a)(3) of this section and 40 CFR 1036.740(a)(4).
    (2) The limit specified in paragraph (b)(1) of this section does 
not limit the amount of advanced technology credits that can be used 
within a service class group if they were generated in that same 
service class group.
    (c) Credit life. Credits expire after five years.
    (d) Other restrictions. Other sections of this part specify 
additional restrictions for using emission credits under certain 
special provisions.

Sec.  1037.745  End-of-year CO2 credit deficits.

    Except as allowed by this section, we may void the certificate of 
any vehicle family certified to an FEL above the applicable standard 
for which you do not have sufficient credits by the deadline for 
submitting the final report.
    (a) Your certificate for a vehicle family for which you do not have 
sufficient CO2 credits will not be void if you remedy the 
deficit with surplus credits within three model years. For example, if 
you have a credit deficit of 500 Mg for a vehicle family at the end of 
model year 2015, you must generate (or otherwise obtain) a surplus of 
at least 500 Mg in that same averaging set by the end of model year 
2018.
    (b) You may apply only surplus credits to your deficit. You may not 
apply credits to a deficit from an earlier model year if they were 
generated in a model year for which any of your vehicle families for 
that averaging set had an end-of-year credit deficit.
    (c) If you do not remedy the deficit with surplus credits within 
three model years, we may void your certificate for that vehicle 
family. Note that voiding a certificate applies ab initio. Where the 
net deficit is less than the total amount of negative credits 
originally generated by the family, we will void the certificate only 
with respect to the number of vehicles needed to reach the amount of 
the net deficit. For example, if the original vehicle family generated 
500 Mg of negative credits, and the manufacturer's net deficit after 
three years was 250 Mg, we would void the certificate with respect to 
half of the vehicles in the family.

Sec.  1037.750  What can happen if I do not comply with the provisions 
of this subpart?

    (a) For each vehicle family participating in the ABT program, the 
certificate of conformity is conditioned upon full compliance with the 
provisions of this subpart during and after the model year. You are 
responsible to establish to our satisfaction that you fully comply with 
applicable requirements. We may void the certificate of conformity for 
a vehicle family if you fail to comply with any provisions of this 
subpart.
    (b) You may certify your vehicle family or subfamily to an FEL 
above an applicable standard based on a projection that you will have 
enough emission credits to offset the deficit for the vehicle family. 
See Sec.  1037.745 for provisions specifying what happens if you cannot 
show in your final report that you have enough actual emission credits 
to offset a deficit for any pollutant in a vehicle family.

[[Page 57428]]

    (c) We may void the certificate of conformity for a vehicle family 
if you fail to keep records, send reports, or give us information we 
request. Note that failing to keep records, send reports, or give us 
information we request is also a violation of 42 U.S.C. 7522(a)(2).
    (d) You may ask for a hearing if we void your certificate under 
this section (see Sec.  1037.820).

Sec.  1037.755  Information provided to the Department of 
Transportation.

    After receipt of each manufacturer's final report as specified in 
Sec.  1037.730 and completion of any verification testing required to 
validate the manufacturer's submitted final data, we will issue a 
report to the Department of Transportation with CO2 emission 
information and will verify the accuracy of each manufacturer's 
equivalent fuel consumption data required by NHTSA under 49 CFR 535.8. 
We will send a report to DOT for each vehicle manufacturer based on 
each regulatory category and subcategory, including sufficient 
information for NHTSA to determine fuel consumption and associated 
credit values. See 49 CFR 535.8 to determine if NHTSA deems submission 
of this information to EPA to also be a submission to NHTSA.

Subpart I--Definitions and Other Reference Information

Sec.  1037.801  Definitions.

    The following definitions apply to this part. The definitions apply 
to all subparts unless we note otherwise. All undefined terms have the 
meaning the Act gives to them. The definitions follow:
    A to B testing means testing performed in pairs to allow comparison 
of vehicle A to vehicle B.
    Act means the Clean Air Act, as amended, 42 U.S.C. 7401-7671q.
    Adjustable parameter means any device, system, or element of design 
that someone can adjust (including those which are difficult to access) 
and that, if adjusted, may affect measured or modeled emissions (as 
applicable). You may ask us to exclude a parameter that is difficult to 
access if it cannot be adjusted to affect emissions without 
significantly degrading vehicle performance, or if you otherwise show 
us that it will not be adjusted in a way that affects emissions during 
in-use operation.
    Adjusted Loaded Vehicle Weight means the numerical average of 
vehicle curb weight and GVWR.
    Advanced technology means vehicle technology certified under Sec.  
1037.615, Sec.  1037.104(d)(7), or 40 CFR 1036.615.
    Aftertreatment means relating to a catalytic converter, particulate 
filter, or any other system, component, or technology mounted 
downstream of the exhaust valve (or exhaust port) whose design function 
is to decrease emissions in the vehicle exhaust before it is exhausted 
to the environment. Exhaust-gas recirculation (EGR) and turbochargers 
are not aftertreatment.
    Alcohol-fueled vehicle means a vehicle that is designed to run 
using an alcohol fuel. For purposes of this definition, alcohol fuels 
do not include fuels with a nominal alcohol content below 25 percent by 
volume.
    Auxiliary emission control device means any element of design that 
senses temperature, motive speed, engine RPM, transmission gear, or any 
other parameter for the purpose of activating, modulating, delaying, or 
deactivating the operation of any part of the emission control system.
    Averaging set has the meaning given in Sec.  1037.701.
    Cab-complete vehicle means a vehicle that is first sold as an 
incomplete vehicle that substantially includes its cab. Vehicles known 
commercially as chassis-cabs, cab-chassis, box-deletes, bed-deletes, 
cut-away vans are considered cab-complete vehicles. For purposes of 
this definition, a cab includes a steering column and passenger 
compartment. Note a vehicle lacking some components of the cab is a 
cab-complete vehicle if it substantially includes the cab.
    Calibration means the set of specifications and tolerances specific 
to a particular design, version, or application of a component or 
assembly capable of functionally describing its operation over its 
working range.
    Carbon-related exhaust emissions (CREE) has the meaning given in 40 
CFR 600.002. Note that CREE represents the combined mass of carbon 
emitted as HC, CO, and CO2, expressed as having a molecular 
weight equal to that of CO2.
    Carryover means relating to certification based on emission data 
generated from an earlier model year.
    Certification means relating to the process of obtaining a 
certificate of conformity for a vehicle family that complies with the 
emission standards and requirements in this part.
    Certified emission level means the highest deteriorated emission 
level in a vehicle family for a given pollutant from either transient 
or steady-state testing.
    Class means relating to GVWR classes, as follows:
    (1) Class 2b means heavy-duty motor vehicles at or below 10,000 
pounds GVWR.
    (2) Class 3 means heavy-duty motor vehicles above 10,000 pounds 
GVWR but at or below 14,000 pounds GVWR.
    (3) Class 4 means heavy-duty motor vehicles above 14,000 pounds 
GVWR but at or below 16,000 pounds GVWR.
    (4) Class 5 means heavy-duty motor vehicles above 16,000 pounds 
GVWR but at or below 19,500 pounds GVWR.
    (5) Class 6 means heavy-duty motor vehicles above 19,500 pounds 
GVWR but at or below 26,000 pounds GVWR.
    (6) Class 7 means heavy-duty motor vehicles above 26,000 pounds 
GVWR but at or below 33,000 pounds GVWR.
    (7) Class 8 means heavy-duty motor vehicles above 33,000 pounds 
GVWR.
    Complete vehicle has the meaning given in the definition of vehicle 
in this section.
    Compression-ignition means relating to a type of reciprocating, 
internal-combustion engine that is not a spark-ignition engine.
    Curb weight has the meaning given in 40 CFR 86.1803, consistent 
with the provisions of Sec.  1037.140.
    Date of manufacture means the date on which the certifying vehicle 
manufacturer completes its manufacturing operations, except as follows:
    (1) Where the certificate holder is an engine manufacturer that 
does not manufacture the chassis, the date of manufacture of the 
vehicle is based on the date assembly of the vehicle is completed.
    (2) We may approve an alternate date of manufacture based on the 
date on which the certifying (or primary) manufacturer completes 
assembly at the place of main assembly, consistent with the provisions 
of Sec.  1037.601 and 49 CFR 567.4.
    Day cab means a type of tractor cab that is not a sleeper cab.
    Designated Compliance Officer means the Manager, Heavy-Duty and 
Nonroad Engine Group (6405-J), U.S. Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460.
    Designated Enforcement Officer means the Director, Air Enforcement 
Division (2242A), U.S. Environmental Protection Agency, 1200 
Pennsylvania Ave., NW., Washington, DC 20460.
    Deteriorated emission level means the emission level that results 
from applying the appropriate deterioration factor to the official 
emission result of the emission-data vehicle. Note that where no 
deterioration factor applies, references in this part to the 
deteriorated emission level mean the official emission result.
    Deterioration factor means the relationship between emissions at 
the

[[Page 57429]]

end of useful life and emissions at the low-hour test point, expressed 
in one of the following ways:
    (1) For multiplicative deterioration factors, the ratio of 
emissions at the end of useful life to emissions at the low-hour test 
point.
    (2) For additive deterioration factors, the difference between 
emissions at the end of useful life and emissions at the low-hour test 
point.
    Driver model means an automated controller that simulates a person 
driving a vehicle.
    Electric vehicle means a vehicle that does not include an engine, 
and is powered solely by an external source of electricity and/or solar 
power. Note that this does not include electric hybrid or fuel-cell 
vehicles that use a chemical fuel such as gasoline, diesel fuel, or 
hydrogen. Electric vehicles may also be referred to as all-electric 
vehicles to distinguish them from hybrid vehicles.
    Emission control system means any device, system, or element of 
design that controls or reduces the emissions of regulated pollutants 
from a vehicle.
    Emission-data vehicle means a vehicle that is tested for 
certification. This includes vehicle tested to establish deterioration 
factors.
    Emission-related maintenance means maintenance that substantially 
affects emissions or is likely to substantially affect emission 
deterioration.
    Excluded means relating to vehicles that are not subject to some or 
all of the requirements of this part as follows:
    (1) A vehicle that has been determined not to be a motor vehicle is 
excluded from this part.
    (2) Certain vehicles are excluded from the requirements of this 
part under Sec.  1037.5.
    (3) Specific regulatory provisions of this part may exclude a 
vehicle generally subject to this part from one or more specific 
standards or requirements of this part.
    Exempted has the meaning given in 40 CFR 1068.30.
    Family emission limit (FEL) means an emission level declared by the 
manufacturer to serve in place of an otherwise applicable emission 
standard under the ABT program in subpart H of this part. The family 
emission limit must be expressed to the same number of decimal places 
as the emission standard it replaces. Note that an FEL may apply as a 
``subfamily'' emission limit.
    Fuel system means all components involved in transporting, 
metering, and mixing the fuel from the fuel tank to the combustion 
chamber(s), including the fuel tank, fuel pump, fuel filters, fuel 
lines, carburetor or fuel-injection components, and all fuel-system 
vents. It also includes components for controlling evaporative 
emissions, such as fuel caps, purge valves, and carbon canisters.
    Fuel type means a general category of fuels such as diesel fuel or 
natural gas. There can be multiple grades within a single fuel type, 
such as high-sulfur or low-sulfur diesel fuel.
    Good engineering judgment has the meaning given in 40 CFR 1068.30. 
See 40 CFR 1068.5 for the administrative process we use to evaluate 
good engineering judgment.
    Gross combination weight rating (GCWR) means the value specified by 
the vehicle manufacturer as the maximum weight of a loaded vehicle and 
trailer, consistent with good engineering judgment. For example, 
compliance with SAE J2807 is generally considered to be consistent with 
good engineering judgment, especially for Class 3 and smaller vehicles.
    Gross vehicle weight rating (GVWR) means the value specified by the 
vehicle manufacturer as the maximum design loaded weight of a single 
vehicle, consistent with good engineering judgment.
    Heavy-duty engine means any engine used for (or for which the 
engine manufacturer could reasonably expect to be used for) motive 
power in a heavy-duty vehicle.
    Heavy-duty vehicle means any motor vehicle above 8,500 pounds GVWR 
or that has a vehicle curb weight above 6,000 pounds or that has a 
basic vehicle frontal area greater than 45 square feet.
    Hybrid engine or hybrid powertrain means an engine or powertrain 
that includes energy storage features other than a conventional battery 
system or conventional flywheel. Supplemental electrical batteries and 
hydraulic accumulators are examples of hybrid energy storage systems. 
Note that certain provisions in this part treat hybrid engines and 
powertrains intended for vehicles that include regenerative braking 
different than those intended for vehicles that do not include 
regenerative braking.
    Hybrid vehicle means a vehicle that includes energy storage 
features (other than a conventional battery system or conventional 
flywheel) in addition to an internal combustion engine or other engine 
using consumable chemical fuel. Supplemental electrical batteries and 
hydraulic accumulators are examples of hybrid energy storage systems. 
Note that certain provisions in this part treat hybrid vehicles that 
include regenerative braking different than those that do not include 
regenerative braking.
    Hydrocarbon (HC) means the hydrocarbon group on which the emission 
standards are based for each fuel type. For alcohol-fueled vehicles, HC 
means nonmethane hydrocarbon equivalent (NMHCE) for exhaust emissions 
and total hydrocarbon equivalent (THCE) for evaporative emissions. For 
all other vehicles, HC means nonmethane hydrocarbon (NMHC) for exhaust 
emissions and total hydrocarbon (THC) for evaporative emissions.
    Identification number means a unique specification (for example, a 
model number/serial number combination) that allows someone to 
distinguish a particular vehicle from other similar vehicles.
    Incomplete vehicle has the meaning given in the definition of 
vehicle in this section.
    Innovative technology means technology certified under Sec.  
1037.610.
    Light-duty truck means any motor vehicle rated at or below 8,500 
pounds GVWR with a curb weight at or below 6,000 pounds and basic 
vehicle frontal area at or below 45 square feet, which is:
    (1) Designed primarily for purposes of transportation of property 
or is a derivation of such a vehicle; or
    (2) Designed primarily for transportation of persons and has a 
capacity of more than 12 persons; or
    (3) Available with special features enabling off-street or off-
highway operation and use.
    Light-duty vehicle means a passenger car or passenger car 
derivative capable of seating 12 or fewer passengers.
    Low-mileage means relating to a vehicle with stabilized emissions 
and represents the undeteriorated emission level. This would generally 
involve approximately 4000 miles of operation.
    Low rolling resistance tire means a tire on a vocational vehicle 
with a TRRL at or below of 7.7 kg/metric ton, a steer tire on a tractor 
with a TRRL at or below 7.7 kg/metric ton, or a drive tire on a tractor 
with a TRRL at or below 8.1 kg/metric ton.
    Manufacture means the physical and engineering process of 
designing, constructing, and/or assembling a vehicle.
    Manufacturer has the meaning given in section 216(1) of the Act. In 
general, this term includes any person who manufactures a vehicle or 
vehicle for sale in the United States or otherwise introduces a new 
motor vehicle into commerce in the United States. This includes 
importers who import vehicles or vehicles for resale.

[[Page 57430]]

    Medium-duty passenger vehicle (MDPV) has the meaning given in 40 
CFR 86.1803.
    Model year means the manufacturer's annual new model production 
period, except as restricted under this definition and 40 CFR part 85, 
subpart X. It must include January 1 of the calendar year for which the 
model year is named, may not begin before January 2 of the previous 
calendar year, and it must end by December 31 of the named calendar 
year.
    (1) The manufacturer who holds the certificate of conformity for 
the vehicle must assign the model year based on the date when its 
manufacturing operations are completed relative to its annual model 
year period. In unusual circumstances where completion of your assembly 
is delayed, we may allow you to assign a model year one year earlier, 
provided it does not affect which regulatory requirements will apply.
    (2) Unless a vehicle is being shipped to a secondary manufacturer 
that will hold the certificate of conformity, the model year must be 
assigned prior to introduction of the vehicle into U.S. commerce. The 
certifying manufacturer must redesignate the model year if it does not 
complete its manufacturing operations within the originally identified 
model year. A vehicle introduced into U.S. commerce without a model 
year is deemed to have a model year equal to the calendar year of its 
introduction into U.S. commerce unless the certifying manufacturer 
assigns a later date.
    Motor vehicle has the meaning given in 40 CFR 85.1703.
    New motor vehicle means a motor vehicle meeting the criteria of 
either paragraph (1) or (2) of this definition. New motor vehicles may 
be complete or incomplete.
    (1) A motor vehicle for which the ultimate purchaser has never 
received the equitable or legal title is a new motor vehicle. This kind 
of vehicle might commonly be thought of as ``brand new'' although a new 
motor vehicle may include previously used parts. Under this definition, 
the vehicle is new from the time it is produced until the ultimate 
purchaser receives the title or places it into service, whichever comes 
first.
    (2) An imported heavy-duty motor vehicle originally produced after 
the 1969 model year is a new motor vehicle.
    Noncompliant vehicle means a vehicle that was originally covered by 
a certificate of conformity, but is not in the certified configuration 
or otherwise does not comply with the conditions of the certificate.
    Nonconforming vehicle means a vehicle not covered by a certificate 
of conformity that would otherwise be subject to emission standards.
    Nonmethane hydrocarbons (NMHC) means the sum of all hydrocarbon 
species except methane, as measured according to 40 CFR part 1065.
    Official emission result means the measured emission rate for an 
emission-data vehicle on a given duty cycle before the application of 
any required deterioration factor, but after the applicability of 
regeneration adjustment factors.
    Owners manual means a document or collection of documents prepared 
by the vehicle manufacturer for the owners or operators to describe 
appropriate vehicle maintenance, applicable warranties, and any other 
information related to operating or keeping the vehicle. The owners 
manual is typically provided to the ultimate purchaser at the time of 
sale.
    Oxides of nitrogen has the meaning given in 40 CFR 1065.1001.
    Particulate trap means a filtering device that is designed to 
physically trap all particulate matter above a certain size.
    Percent has the meaning given in 40 CFR 1065.1001. Note that this 
means percentages identified in this part are assumed to be infinitely 
precise without regard to the number of significant figures. For 
example, one percent of 1,493 is 14.93.
    Placed into service means put into initial use for its intended 
purpose.
    Power take-off (PTO) means a secondary engine shaft (or equivalent) 
that provides substantial auxiliary power for purposes unrelated to 
vehicle propulsion or normal vehicle accessories such as air 
conditioning, power steering, and basic electrical accessories. A 
typical PTO uses a secondary shaft on the engine to transmit power to a 
hydraulic pump that powers auxiliary equipment, such as a boom on a 
bucket truck. You may ask us to consider other equivalent auxiliary 
power configurations (such as those with hybrid vehicles) as power 
take-off systems.
    Rechargeable Energy Storage System (RESS) means the component(s) of 
a hybrid engine or vehicle that store recovered energy for later use, 
such as the battery system in an electric hybrid vehicle.
    Regulatory sub-category means one of following groups:
    (1) Spark-ignition vehicles subject to the standards of Sec.  
1037.104. Note that this category includes most gasoline-fueled heavy-
duty pickup trucks and vans.
    (2) All other vehicles subject to the standards of Sec.  1037.104. 
Note that this category includes most diesel-fueled heavy-duty pickup 
trucks and van.
    (3) Vocational vehicles at or below 19,500 pounds GVWR.
    (4) Vocational vehicles at or above 19,500 pounds GVWR but below 
33,000 pounds GVWR.
    (5) Vocational vehicles over 33,000 pounds GVWR.
    (6) Low-roof tractors at or above 26,000 pounds GVWR but below 
33,000 pounds GVWR.
    (7) Mid-roof tractors at or above 26,000 pounds GVWR but below 
33,000 pounds GVWR.
    (8) High-roof tractors at or above 26,000 pounds GVWR but below 
33,000 pounds GVWR.
    (9) Low-roof day cab tractors at or above 33,000 pounds GVWR.
    (10) Low-roof sleeper cab tractors at or above 33,000 pounds GVWR.
    (11) Mid-roof day cab tractors at or above 33,000 pounds GVWR.
    (12) Mid-roof sleeper cab tractors at or above 33,000 pounds GVWR.
    (13) High-roof day cab tractors at or above 33,000 pounds GVWR.
    (14) High-roof sleeper cab tractors at or above 33,000 pounds GVWR.
    Relating to as used in this section means relating to something in 
a specific, direct manner. This expression is used in this section only 
to define terms as adjectives and not to broaden the meaning of the 
terms.
    Revoke has the meaning given in 40 CFR 1068.30.
    Roof height means the maximum height of a vehicle (rounded to the 
nearest inch), excluding narrow accessories such as exhaust pipes and 
antennas, but including any wide accessories such as roof fairings. 
Measure roof height of the vehicle configured to have its maximum 
height that will occur during actual use, with properly inflated tires 
and no driver, passengers, or cargo onboard. Roof height may also refer 
to the following categories:
    (1) Low-roof means relating to a vehicle with a roof height of 120 
inches or less.
    (2) Mid-roof means relating to a vehicle with a roof height of 121 
to 147 inches.
    (3) High-roof means relating to a vehicle with a roof height of 148 
inches or more.
    Round has the meaning given in 40 CFR 1065.1001.
    Scheduled maintenance means adjusting, repairing, removing, 
disassembling, cleaning, or replacing components or systems 
periodically to keep a part or system from failing,

[[Page 57431]]

malfunctioning, or wearing prematurely. It also may mean actions you 
expect are necessary to correct an overt indication of failure or 
malfunction for which periodic maintenance is not appropriate.
    Sleeper cab means a type of tractor cab that has a compartment 
behind the driver's seat intended to be used by the driver for 
sleeping. This includes cabs accessible from the driver's compartment 
and those accessible from outside the vehicle.
    Small manufacturer means a manufacturer meeting the criteria 
specified in 13 CFR 121.201. For manufacturers owned by a parent 
company, the employee and revenue limits apply to the total number 
employees and total revenue of the parent company and all its 
subsidiaries.
    Spark-ignition means relating to a gasoline-fueled engine or any 
other type of engine with a spark plug (or other sparking device) and 
with operating characteristics significantly similar to the theoretical 
Otto combustion cycle. Spark-ignition engines usually use a throttle to 
regulate intake air flow to control power during normal operation.
    Standard payload means the vehicle payload assumed for each class 
in tons for modeling and calculating emission credits. There are three 
standard payloads:
    (1) 2.85 tons for light heavy-duty vehicles.
    (2) 5.6 tons for medium heavy-duty vehicles.
    (3) 7.5 tons for heavy heavy-duty vehicles.
    Standard trailer has the meaning given in Sec.  1037.501.
    Suspend has the meaning given in 40 CFR 1068.30.
    Test sample means the collection of vehicles selected from the 
population of a vehicle family for emission testing. This may include 
testing for certification, production-line testing, or in-use testing.
    Test vehicle means a vehicle in a test sample.
    Test weight means the vehicle weight used or represented during 
testing.
    Tire rolling resistance level (TRRL) means a value with units of 
kg/metric ton that represents that rolling resistance of a tire 
configuration. TRRLs are used as inputs to the GEM model under Sec.  
1037.520. Note that a manufacturer may assign a value higher than the 
measured rolling resistance of a tire configuration.
    Total hydrocarbon has the meaning given in 40 CFR 1065.1001. This 
generally means the combined mass of organic compounds measured by the 
specified procedure for measuring total hydrocarbon, expressed as a 
hydrocarbon with an atomic hydrogen-to-carbon ratio of 1.85:1.
    Total hydrocarbon equivalent has the meaning given in 40 CFR 
1065.1001. This generally means the sum of the carbon mass 
contributions of non-oxygenated hydrocarbons, alcohols and aldehydes, 
or other organic compounds that are measured separately as contained in 
a gas sample, expressed as exhaust hydrocarbon from petroleum-fueled 
vehicles. The atomic hydrogen-to-carbon ratio of the equivalent 
hydrocarbon is 1.85:1.
    Tractor has the meaning given for ``truck tractor'' in 49 CFR 
571.3. This includes most heavy-duty vehicles specifically designed for 
the primary purpose of pulling trailers, but does not include vehicles 
designed to carry other loads. For purposes of this definition ``other 
loads'' would not include loads carried in the cab, sleeper 
compartment, or toolboxes. Examples of vehicles that are similar to 
tractors but that are not tractors under this part include dromedary 
tractors, automobile haulers, straight trucks with trailers hitches, 
and tow trucks. Note that the provisions of this part that apply for 
tractors do not apply for tractors that are classified as vocational 
tractors under Sec.  1037.630.
    Ultimate purchaser means, with respect to any new vehicle, the 
first person who in good faith purchases such new vehicle for purposes 
other than resale.
    United States has the meaning given in 40 CFR 1068.30.
    Upcoming model year means for a vehicle family the model year after 
the one currently in production.
    U.S.-directed production volume means the number of vehicle units, 
subject to the requirements of this part, produced by a manufacturer 
for which the manufacturer has a reasonable assurance that sale was or 
will be made to ultimate purchasers in the United States. This does not 
include vehicles certified to state emission standards that are 
different than the emission standards in this part.
    Useful life means the period during which a vehicle is required to 
comply with all applicable emission standards.
    Vehicle means equipment intended for use on highways that meets the 
criteria of paragraph (1)(i) or (1)(ii) of this definition, as follows:
    (1) The following equipment are vehicles:
    (i) A piece of equipment that is intended for self-propelled use on 
highways becomes a vehicle when it includes at least an engine, a 
transmission, and a frame. (Note: For purposes of this definition, any 
electrical, mechanical, and/or hydraulic devices attached to engines 
for the purpose of powering wheels are considered to be transmissions.)
    (ii) A piece of equipment that is intended for self-propelled use 
on highways becomes a vehicle when it includes a passenger compartment 
attached to a frame with axles.
    (2) Vehicles may be complete or incomplete vehicles as follows:
    (i) A complete vehicle is a functioning vehicle that has the 
primary load carrying device or container (or equivalent equipment) 
attached. Examples of equivalent equipment would include fifth wheel 
trailer hitches, firefighting equipment, and utility booms.
    (ii) An incomplete vehicle is a vehicle that is not a complete 
vehicle. Incomplete vehicles may also be cab-complete vehicles. This 
may include vehicles sold to secondary vehicle manufacturers.
    (iii) The primary use of the terms ``complete vehicle'' and 
``incomplete vehicle'' are to distinguish whether a vehicle is complete 
when it is first sold as a vehicle.
    (iv) You may ask us to allow you to certify a vehicle as incomplete 
if you manufacture the engines and sell the unassembled chassis 
components, as long as you do not produce and sell the body components 
necessary to complete the vehicle.
    (3) Equipment such as trailers that are not self-propelled are not 
``vehicles'' under this part 1037.
    Vehicle configuration means a unique combination of vehicle 
hardware and calibration (related to measured or modeled emissions) 
within a vehicle family. Vehicles with hardware or software 
differences, but that have no hardware or software differences related 
to measured or modeled emissions may be included in the same vehicle 
configuration. Note that vehicles with hardware or software differences 
related to measured or modeled emissions are considered to be different 
configurations even if they have the same GEM inputs and FEL. Vehicles 
within a vehicle configuration differ only with respect to normal 
production variability or factors unrelated to measured or modeled 
emissions.
    Vehicle family has the meaning given in Sec.  1037.230.
    Vehicle service class means a vehicle's weight class as specified 
in this definition. Note that, while vehicle service class is similar 
to primary intended service class for engines, they are not necessarily 
the same. For example, a medium heavy-duty vehicle may include a light 
heavy-duty engine.

[[Page 57432]]

Note also that while spark-ignition engines do not have a primary 
intended service class, vehicles using spark-ignition engines have a 
vehicle service class.
    (1) Light heavy-duty vehicles are those vehicles with GVWR below 
19,500 pounds.
    Vehicles In this class include heavy-duty pickup trucks and vans, 
motor homes and other recreational vehicles, and some straight trucks 
with a single rear axle. Typical applications would include personal 
transportation, light-load commercial delivery, passenger service, 
agriculture, and construction.
    (2) Medium heavy-duty vehicles are those vehicles with GVWR from 
19,500 to 33,000 pounds. Vehicles in this class include school buses, 
straight trucks with a single rear axle, city tractors, and a variety 
of special purpose vehicles such as small dump trucks, and refuse 
trucks. Typical applications would include commercial short haul and 
intra-city delivery and pickup.
    (3) Heavy heavy-duty vehicles are those vehicles with GVWR above 
33,000 pounds. Vehicles in this class include tractors, urban buses, 
and other heavy trucks.
    Vehicle subfamily or subfamily means a subset of a vehicle family 
including vehicles subject to the same FEL(s).
    Vocational tractor means a vehicle classified as a vocational 
tractor under Sec.  1037.630.
    Vocational vehicle means relating to a vehicle subject to the 
standards of Sec.  1037.105 (including vocational tractors).
    Void has the meaning given in 40 CFR 1068.30.
    Volatile liquid fuel means any fuel other than diesel or biodiesel 
that is a liquid at atmospheric pressure and has a Reid Vapor Pressure 
higher than 2.0 pounds per square inch.
    We (us, our) means the Administrator of the Environmental 
Protection Agency and any authorized representatives.

Sec.  1037.805  Symbols, acronyms, and abbreviations.

    The following symbols, acronyms, and abbreviations apply to this 
part:

ABT Averaging, banking, and trading.
AECD auxiliary emission control device.
CD drag coefficient.
CDA drag area.
CFD computational fluid dynamics.
CFR Code of Federal Regulations.
CH4 methane.
CO carbon monoxide.
CO2 carbon dioxide.
CREE carbon-related exhaust emissions.
DOT Department of Transportation.
EPA Environmental Protection Agency.
ETW equivalent test weight.
FEL Family Emission Limit.
g grams.
GAWR gross axle weight rating.
GCWR gross combination weight rating.
GVWR gross vehicle weight rating.
GWP global-warming potential.
HC hydrocarbon.
ISO International Organization for Standardization.
kg kilograms.
m meter.
mm millimeter
mph miles per hour.
N2O nitrous oxide.
NARA National Archives and Records Administration.
NHTSA National Highway Transportation Safety Administration.
NOX oxides of nitrogen (NO and NO2).
PM particulate matter.
PTO power take-off.
RESS rechargeable energy storage system.
RPM revolutions per minute.
SAE Society of Automotive Engineers.
SKU Stock-keeping unit.
TRRL Tire rolling resistance level.
U.S.C. United States Code.
VSL vehicle speed limiter.
WF work factor.

Sec.  1037.810  Incorporation by reference.

    (a) Certain material is incorporated by reference into this part 
with the approval of the Director of the Federal Register under 5 
U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other than that 
specified in this section, the Environmental Protection Agency must 
publish a notice of the change in the Federal Register and the material 
must be available to the public. All approved material is available for 
inspection at U.S. EPA, Air and Radiation Docket and Information 
Center, 1301 Constitution Ave., NW., Room B102, EPA West Building, 
Washington, DC 20460, (202) 202-1744, and is available from the sources 
listed below. It is also available for inspection at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to 
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
    (b) International Organization for Standardization, Case Postale 
56, CH-1211 Geneva 20, Switzerland, (41) 22749 0111, http://www.iso.org, or central@iso.org.
    (1) ISO 28580:2009(E) ``Passenger car, truck and bus tyres--Methods 
of measuring rolling resistance--Single point test and correlation of 
measurement results'', First Edition, July 1, 2009; IBR approved for 
Sec.  1037.520(c).
    (2) [Reserved]
    (c) U.S. EPA, Office of Air and Radiation, 2565 Plymouth Road, Ann 
Arbor, MI 48105, http://www.epa.gov:
    (1) GEM simulation tool, Version 2.0, August 2011; IBR approved for 
Sec.  1037.520. The computer code for this model is available as noted 
in paragraph (a) of this section. A working version of this software is 
also available for download at http://www.epa.gov/otaq/climate/gem.htm.
    (2) [Reserved]
    (d) Society of Automotive Engineers, 400 Commonwealth Dr., 
Warrendale, PA 15096-0001, (877) 606-7323 (U.S. and Canada) or (724) 
776-4970 (outside the U.S. and Canada), http://www.sae.org.
    (1) SAE J1252, SAE Wind Tunnel Test Procedure for Trucks and Buses, 
Revised July 1981, IBR approved for Sec.  1037.521(d), (e), and (f).
    (2) SAE J1594, Vehicle Aerodynamics Terminology, Revised July 2010, 
IBR approved for Sec.  1037.521(d).
    (3) SAE J2071, Aerodynamic Testing of Road Vehicles--Open Throat 
Wind Tunnel Adjustment, Revised June 1994, IBR approved for Sec.  
1037.521(d).

Sec.  1037.815  Confidential information.

    The provisions of 40 CFR 1068.10 apply for information you consider 
confidential.

Sec.  1037.820  Requesting a hearing.

    (a) You may request a hearing under certain circumstances, as 
described elsewhere in this part. To do this, you must file a written 
request, including a description of your objection and any supporting 
data, within 30 days after we make a decision.
    (b) For a hearing you request under the provisions of this part, we 
will approve your request if we find that your request raises a 
substantial factual issue.
    (c) If we agree to hold a hearing, we will use the procedures 
specified in 40 CFR part 1068, subpart G.

Sec.  1037.825  Reporting and recordkeeping requirements.

    (a) This part includes various requirements to submit and record 
data or other information. Unless we specify otherwise, store required 
records in any format and on any media and keep them readily available 
for eight years after you send an associated application for 
certification, or eight years after you generate the data if they do 
not support an application for certification. You may not rely on 
anyone else to meet recordkeeping requirements on your behalf unless we 
specifically authorize it. We may review these records at any time. You 
must promptly send us organized, written records in English if we ask 
for them. We may require you to submit written records in an electronic 
format.

[[Page 57433]]

    (b) The regulations in Sec.  1037.255 and 40 CFR 1068.25 and 
1068.101 describe your obligation to report truthful and complete 
information. This includes information not related to certification. 
Failing to properly report information and keep the records we specify 
violates 40 CFR 1068.101(a)(2), which may involve civil or criminal 
penalties.
    (c) Send all reports and requests for approval to the Designated 
Compliance Officer (see Sec.  1037.801).
    (d) Any written information we require you to send to or receive 
from another company is deemed to be a required record under this 
section. Such records are also deemed to be submissions to EPA. Keep 
these records for eight years unless the regulations specify a 
different period. We may require you to send us these records whether 
or not you are a certificate holder.
    (e) Under the Paperwork Reduction Act (44 U.S.C. 3501 et seq), the 
Office of Management and Budget approves the reporting and 
recordkeeping specified in the applicable regulations. The following 
items illustrate the kind of reporting and recordkeeping we require for 
vehicles regulated under this part:
    (1) We specify the following requirements related to vehicle 
certification in this part 1037:
    (i) In subpart C of this part we identify a wide range of 
information required to certify vehicles.
    (ii) In subpart G of this part we identify several reporting and 
recordkeeping items for making demonstrations and getting approval 
related to various special compliance provisions.
    (iii) In Sec.  1037.725, 1037.730, and 1037.735 we specify certain 
records related to averaging, banking, and trading.
    (2) We specify the following requirements related to testing in 40 
CFR part 1066:
    (i) In 40 CFR 1065.2 we give an overview of principles for 
reporting information.
    (ii) In 40 CFR 1065.10 and 1065.12 we specify information needs for 
establishing various changes to published test procedures.
    (iii) In 40 CFR 1065.25 we establish basic guidelines for storing 
test information.
    (iv) In 40 CFR 1065.695 we identify data that may be appropriate 
for collecting during testing of in-use vehicles using portable 
analyzers.

    Appendix I to Part 1037--Heavy-Duty Transient Chassis Test Cycle
------------------------------------------------------------------------
                                                           Speed   Speed
                        Time sec.                           mph     m/s
------------------------------------------------------------------------
1.......................................................    0.00    0.00
2.......................................................    0.00    0.00
3.......................................................    0.00    0.00
4.......................................................    0.00    0.00
5.......................................................    0.00    0.00
6.......................................................    0.00    0.00
7.......................................................    0.41    0.18
8.......................................................    1.18    0.53
9.......................................................    2.26    1.01
10......................................................    3.19    1.43
11......................................................    3.97    1.77
12......................................................    4.66    2.08
13......................................................    5.32    2.38
14......................................................    5.94    2.66
15......................................................    6.48    2.90
16......................................................    6.91    3.09
17......................................................    7.28    3.25
18......................................................    7.64    3.42
19......................................................    8.02    3.59
20......................................................    8.36    3.74
21......................................................    8.60    3.84
22......................................................    8.74    3.91
23......................................................    8.82    3.94
24......................................................    8.82    3.94
25......................................................    8.76    3.92
26......................................................    8.66    3.87
27......................................................    8.58    3.84
28......................................................    8.52    3.81
29......................................................    8.46    3.78
30......................................................    8.38    3.75
31......................................................    8.31    3.71
32......................................................    8.21    3.67
33......................................................    8.11    3.63
34......................................................    8.00    3.58
35......................................................    7.94    3.55
36......................................................    7.94    3.55
37......................................................    7.80    3.49
38......................................................    7.43    3.32
39......................................................    6.79    3.04
40......................................................    5.81    2.60
41......................................................    4.65    2.08
42......................................................    3.03    1.35
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50......................................................    2.31    1.03
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66......................................................    8.84    3.95
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261.....................................................    3.07    1.37
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264.....................................................    6.95    3.11
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333.....................................................   15.07    6.74
334.....................................................   12.23    5.47
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417.....................................................   14.72    6.58
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420.....................................................   10.43    4.66
421.....................................................    8.71    3.89
422.....................................................    7.44    3.33
423.....................................................    5.71    2.55
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425.....................................................    2.30    1.03
426.....................................................    1.00    0.45
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429.....................................................    1.19    0.53
430.....................................................    1.61    0.72
431.....................................................    1.53    0.68
432.....................................................    2.34    1.05
433.....................................................    4.29    1.92
434.....................................................    7.25    3.24
435.....................................................   10.20    4.56
436.....................................................   12.46    5.57
437.....................................................   14.53    6.50
438.....................................................   16.22    7.25
439.....................................................   17.87    7.99
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443.....................................................   22.62   10.11
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445.....................................................   24.88   11.12
446.....................................................   26.15   11.69
447.....................................................   26.99   12.07
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451.....................................................   29.83   13.34
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454.....................................................   32.78   14.65
455.....................................................   33.24   14.86
456.....................................................   33.47   14.96
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458.....................................................   33.08   14.79
459.....................................................   32.78   14.65
460.....................................................   32.39   14.48
461.....................................................   32.13   14.36
462.....................................................   31.82   14.22
463.....................................................   31.55   14.10
464.....................................................   31.25   13.97
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468.....................................................   30.79   13.76
469.....................................................   31.13   13.92
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471.....................................................   31.51   14.09
472.....................................................   31.47   14.07
473.....................................................   31.44   14.05
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475.....................................................   31.59   14.12
476.....................................................   31.67   14.16
477.....................................................   32.01   14.31
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479.....................................................   33.39   14.93
480.....................................................   34.31   15.34
481.....................................................   34.81   15.56
482.....................................................   34.20   15.29
483.....................................................   32.39   14.48
484.....................................................   30.29   13.54
485.....................................................   28.56   12.77
486.....................................................   26.45   11.82
487.....................................................   24.79   11.08
488.....................................................   23.12   10.34
489.....................................................   20.73    9.27
490.....................................................   18.33    8.19
491.....................................................   15.72    7.03
492.....................................................   13.11    5.86
493.....................................................   10.47    4.68
494.....................................................    7.82    3.50
495.....................................................    5.70    2.55
496.....................................................    3.57    1.60
497.....................................................    0.92    0.41
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523.....................................................    1.50    0.67
524.....................................................    3.00    1.34
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527.....................................................    6.52    2.91
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531.....................................................    6.33    2.83
532.....................................................    6.71    3.00
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535.....................................................    7.33    3.28
536.....................................................    6.71    3.00
537.....................................................    6.41    2.87
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541.....................................................    5.45    2.44
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569.....................................................   13.00    5.81
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579.....................................................   22.66   10.13
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581.....................................................   25.42   11.36
582.....................................................   25.53   11.41
583.....................................................   26.68   11.93
584.....................................................   28.14   12.58
585.....................................................   30.06   13.44
586.....................................................   30.94   13.83
587.....................................................   31.63   14.14
588.....................................................   32.36   14.47
589.....................................................   33.24   14.86
590.....................................................   33.66   15.05
591.....................................................   34.12   15.25
592.....................................................   35.92   16.06
593.....................................................   37.72   16.86
594.....................................................   39.26   17.55
595.....................................................   39.45   17.64
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597.....................................................   40.18   17.96
598.....................................................   40.48   18.10
599.....................................................   40.75   18.22
600.....................................................   41.02   18.34
601.....................................................   41.36   18.49
602.....................................................   41.79   18.68
603.....................................................   42.40   18.95
604.....................................................   42.82   19.14
605.....................................................   43.05   19.25
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607.....................................................   43.24   19.33
608.....................................................   43.59   19.49
609.....................................................   44.01   19.67
610.....................................................   44.35   19.83
611.....................................................   44.55   19.92
612.....................................................   44.82   20.04
613.....................................................   45.05   20.14
614.....................................................   45.31   20.26
615.....................................................   45.58   20.38
616.....................................................   46.00   20.56
617.....................................................   46.31   20.70
618.....................................................   46.54   20.81
619.....................................................   46.61   20.84
620.....................................................   46.92   20.98
621.....................................................   47.19   21.10
622.....................................................   47.46   21.22
623.....................................................   47.54   21.25
624.....................................................   47.54   21.25
625.....................................................   47.54   21.25
626.....................................................   47.50   21.23
627.....................................................   47.50   21.23
628.....................................................   47.50   21.23
629.....................................................   47.31   21.15
630.....................................................   47.04   21.03
631.....................................................   46.77   20.91
632.....................................................   45.54   20.36
633.....................................................   43.24   19.33
634.....................................................   41.52   18.56
635.....................................................   39.79   17.79
636.....................................................   38.07   17.02
637.....................................................   36.34   16.25
638.....................................................   34.04   15.22
639.....................................................   32.45   14.51
640.....................................................   30.86   13.80
641.....................................................   28.83   12.89
642.....................................................   26.45   11.82
643.....................................................   24.27   10.85
644.....................................................   22.04    9.85
645.....................................................   19.82    8.86
646.....................................................   17.04    7.62
647.....................................................   14.26    6.37
648.....................................................   11.52    5.15
649.....................................................    8.78    3.93
650.....................................................    7.17    3.21
651.....................................................    5.56    2.49
652.....................................................    3.72    1.66
653.....................................................    3.38    1.51
654.....................................................    3.11    1.39
655.....................................................    2.58    1.15
656.....................................................    1.66    0.74
657.....................................................    0.67    0.30
658.....................................................    0.00    0.00
659.....................................................    0.00    0.00
660.....................................................    0.00    0.00
661.....................................................    0.00    0.00
662.....................................................    0.00    0.00
663.....................................................    0.00    0.00
664.....................................................    0.00    0.00
665.....................................................    0.00    0.00
666.....................................................    0.00    0.00
667.....................................................    0.00    0.00
668.....................................................    0.00    0.00
------------------------------------------------------------------------

                               Appendix II to Part 1037--Power Take-Off Test Cycle
----------------------------------------------------------------------------------------------------------------
                                                                          Start     Normalized      Normalized
                       Cycle simulation                           Mode   time of     pressure,       pressure,
                                                                           mode   circuit 1  (%)  circuit 2  (%)
----------------------------------------------------------------------------------------------------------------
Utility.......................................................        0        0             0.0             0.0
Utility.......................................................        1       33            80.5             0.0
Utility.......................................................        2       40             0.0             0.0
Utility.......................................................        3      145            83.5             0.0
Utility.......................................................        4      289             0.0             0.0
Refuse........................................................        5      361             0.0            13.0
Refuse........................................................        6      363             0.0            38.0
Refuse........................................................        7      373             0.0            53.0
Refuse........................................................        8      384             0.0            73.0
Refuse........................................................        9      388             0.0             0.0
Refuse........................................................       10      401             0.0            13.0
Refuse........................................................       11      403             0.0            38.0
Refuse........................................................       12      413             0.0            53.0
Refuse........................................................       13      424             0.0            73.0
Refuse........................................................       14      442            11.2             0.0
Refuse........................................................       15      468            29.3             0.0
Refuse........................................................       16      473             0.0             0.0
Refuse........................................................       17      486            11.2             0.0
Refuse........................................................       18      512            29.3             0.0
Refuse........................................................       19      517             0.0             0.0
Refuse........................................................       20      530            12.8            11.1
Refuse........................................................       21      532            12.8            38.2

[[Page 57437]]

 
Refuse........................................................       22      541            12.8            53.4
Refuse........................................................       23      550            12.8            73.5
Refuse........................................................       24      553             0.0             0.0
Refuse........................................................       25      566            12.8            11.1
Refuse........................................................       26      568            12.8            38.2
Refuse........................................................       27      577            12.8            53.4
Refuse........................................................       28      586            12.8            73.5
Refuse........................................................       29      589             0.0             0.0
Refuse........................................................       30      600             0.0             0.0
----------------------------------------------------------------------------------------------------------------

Appendix III to Part 1037--Emission Control Identifiers

    This appendix identifies abbreviations for emission control 
information labels, as required under Sec.  1037.135.

Vehicle Speed Limiters

-VSL--Vehicle speed limiter
-VSLS--``Soft-top'' vehicle speed limiter
-VSLE--Expiring vehicle speed limiter
-VSLD--Vehicle speed limiter with both ``soft-top'' and expiration

Idle Reduction Technology

-IRT5--Engine shutoff after 5 minutes or less of idling
-IRTE--Expiring engine shutoff

Tires

-LRRA--Low rolling resistance tires (all)
-LRRD--Low rolling resistance tires (drive)
-LRRS--Low rolling resistance tires (steer)

Aerodynamic Components

-ATS--Aerodynamic side skirt and/or fuel tank fairing
-ARF--Aerodynamic roof fairing
-ARFR--Adjustable height aerodynamic roof fairing
-TGR--Gap reducing fairing (tractor to trailer gap)

Other Components

-ADVH--Vehicle includes advanced hybrid technology components
-ADVO--Vehicle includes other advanced technology components (i.e., 
non-hybrid system)
-INV--Vehicle includes innovative technology components

PART 1039--CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD 
COMPRESSION-IGNITION ENGINES

0
35. The authority citation for part 1039 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

Subpart F--[Amended]

0
36. Section 1039.510 is amended by revising paragraph (b) introductory 
text to read as follows:

Sec.  1039.510  Which duty cycles do I use for transient testing?

* * * * *
    (b) The transient test sequence consists of an initial run through 
the transient duty cycle from a cold start, 20 minutes with no engine 
operation, then a final run through the same transient duty cycle. 
Calculate the official transient emission result from the following 
equation:
* * * * *

PART 1065--ENGINE-TESTING PROCEDURES

0
37. The authority citation for part 1065 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

Subpart A--[Amended]

0
38. Section 1065.1 is amended by adding paragraph (h) to read as 
follows:

Sec.  1065.1  Applicability.

* * * * *
    (h) 40 CFR part 1066 describes how to measure emissions from 
vehicles that are subject to standards in g/mile or g/kilometer. Those 
vehicle testing provisions extensively reference portions of this part 
1065. See 40 CFR part 1066 and the standard-setting part for additional 
information.

0
39. Section 1065.15 is amended by revising paragraph (e) to read as 
follows:

Sec.  1065.15  Overview of procedures for laboratory and field testing.

* * * * *
    (e) The following figure illustrates the allowed measurement 
configurations described in this part 1065:
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[GRAPHIC] [TIFF OMITTED] TR15SE11.019

BILLING CODE 4910-59-C
* * * * *

0
40. Section 1065.20 is amended by revising paragraphs (a) introductory 
text, (a)(1), and (e) to read as follows:

Sec.  1065.20  Units of measure and overview of calculations.

    (a) System of units. The procedures in this part generally follow 
the

[[Page 57439]]

International System of Units (SI), as detailed in NIST Special 
Publication 811, which we incorporate by reference in Sec.  1065.1010. 
The following exceptions apply:
    (1) We designate angular speed, fn, of an engine's 
crankshaft in revolutions per minute (r/min), rather than the SI unit 
of radians per second (rad/s). This is based on the commonplace use of 
r/min in many engine dynamometer laboratories.
* * * * *
    (e) Rounding. You are required to round certain final values, such 
as final emission values. You may round intermediate values when 
transferring data as long as you maintain at least six significant 
digits (which requires more than six decimal places for values less 
than 0.1), or all significant digits if fewer than six digits are 
available. Unless the standard-setting part specifies otherwise, do not 
round other intermediate values. Round values to the number of 
significant digits necessary to match the number of decimal places of 
the applicable standard or specification as described in this paragraph 
(e). Note that specifications expressed as percentages have infinite 
precision (as described in paragraph (e)(7) of this section). Use the 
following rounding convention, which is consistent with ASTM E29 and 
NIST SP 811:
    (1) If the first (left-most) digit to be removed is less than five, 
remove all the appropriate digits without changing the digits that 
remain. For example, 3.141593 rounded to the second decimal place is 
3.14.
    (2) If the first digit to be removed is greater than five, remove 
all the appropriate digits and increase the lowest-value remaining 
digit by one. For example, 3.141593 rounded to the fourth decimal place 
is 3.1416.
    (3) If the first digit to be removed is five with at least one 
additional non-zero digit following the five, remove all the 
appropriate digits and increase the lowest-value remaining digit by 
one. For example, 3.141593 rounded to the third decimal place is 3.142.
    (4) If the first digit to be removed is five with no additional 
non-zero digits following the five, remove all the appropriate digits, 
increase the lowest-value remaining digit by one if it is odd and leave 
it unchanged if it is even. For example, 1.75 and 1.750 rounded to the 
first decimal place are 1.8; while 1.85 and 1.850 rounded to the first 
decimal place are also 1.8. Note that this rounding procedure will 
always result in an even number for the lowest-value digit.
    (5) This paragraph (e)(5) applies if the regulation specifies 
rounding to an increment other than decimal places or powers of ten (to 
the nearest 0.01, 0.1, 1, 10, 100, etc.). To round numbers for these 
special cases, divide the quantity by the specified rounding increment. 
Round the result to the nearest whole number as described in paragraphs 
(e)(1) through (4) of this section. Multiply the rounded number by the 
specified rounding increment. This value is the desired result. For 
example, to round 0.90 to the nearest 0.2, divide 0.90 by 0.2 to get a 
result of 4.5, which rounds to 4. Multiplying 4 by 0.2 gives 0.8, which 
is the result of rounding 0.90 to the nearest 0.2.
    (6) The following tables further illustrate the rounding procedures 
specified in this paragraph (e):

 
----------------------------------------------------------------------------------------------------------------
                                                                        Rounding increment
                    Quantity                     ---------------------------------------------------------------
                                                        10               1              0.1            0.01
----------------------------------------------------------------------------------------------------------------
3.141593........................................               0               3             3.1            3.14
123,456.789.....................................         123,460         123,457       123,456.8      123,456.79
5.500...........................................              10               6             5.5            5.50
4.500...........................................               0               4             4.5            4.50
----------------------------------------------------------------------------------------------------------------

 
----------------------------------------------------------------------------------------------------------------
                                                                        Rounding increment
                    Quantity                     ---------------------------------------------------------------
                                                        25               3              0.5            0.02
----------------------------------------------------------------------------------------------------------------
229.267.........................................             225             228           229.5          229.26
62.500..........................................              50              63            62.5           62.50
87.500..........................................             100              87            87.5           87.50
7.500...........................................               0               6             7.5            7.50
----------------------------------------------------------------------------------------------------------------

     (7) This paragraph (e)(7) applies where we specify a limit or 
tolerance as some percentage of another value (such as 2% 
of a maximum concentration). You may show compliance with such 
specifications either by applying the percentage to the total value to 
calculate an absolute limit, or by converting the absolute value to a 
percentage by dividing it by the total value.
    (i) Do not round either value (the absolute limit or the calculated 
percentage), except as specified in paragraph (e)(7)(ii) of this 
section. For example, assume we specify that an analyzer must have a 
repeatability of 1% of the maximum concentration or better, 
the maximum concentration is 1059 ppm, and you determine repeatability 
to be 6.3 ppm. In this example, you could calculate an 
absolute limit of 10.59 ppm (1059 ppm x 0.01) or calculate 
that the 6.3 ppm repeatability is equivalent to a repeatability of 
0.5949008498584%.
    (ii) Prior to July 1, 2013, you may treat tolerances (and 
equivalent specifications) specified in percentages as having fixed 
rather than infinite precision. For example, 2% would be equivalent to 
1.51% to 2.50% and 2.0% would be equivalent to 1.951% to 2.050%. Note 
that this allowance applies whether or not the percentage is explicitly 
specified as a percentage of another value.
    (8) You may use measurement devices that incorporate internal 
rounding, consistent with the provisions of this paragraph (e)(8). You 
may use devices that use any rounding convention if they report six or 
more significant digits. You may use devices that report fewer than six 
digits, consistent with good engineering judgment and the accuracy, 
repeatability, and noise specifications of this part. Note that this 
provision does not necessarily require

[[Page 57440]]

you to perform engineering analysis or keep records.
* * * * *

Subpart B--[Amended]

0
41. Section 1065.125 is amended by revising paragraph (e)(1) 
introductory text to read as follows:

Sec.  1065.125  Engine intake air.

* * * * *
    (e) * * *
    (1) Use a charge-air cooling system with a total intake-air 
capacity that represents production engines' in-use installation. 
Design any laboratory charge-air cooling system to minimize 
accumulation of condensate. Drain any accumulated condensate. Before 
starting a duty cycle (or preconditioning for a duty cycle), completely 
close all drains that would normally be closed during in-use operation. 
Keep those drains closed during the emission test. Maintain coolant 
conditions as follows:
* * * * *

0
42. Section 1065.140 is amended by revising paragraphs (c)(6)(ii)(C) 
and (D) to read as follows:

Sec.  1065.140  Dilution for gaseous and PM constituents.

* * * * *
    (c) * * *
    (6) * * *
    (ii) * * *
    (C) Identify the maximum potential mole fraction of dilute exhaust 
lost on a continuous basis during the entire test interval. This value 
must be less than or equal to 0.02. Calculate on a continuous basis the 
mole fraction of water that would be in equilibrium with liquid water 
at the measured minimum surface temperature. Subtract this mole 
fraction from the mole fraction of water that would be in the exhaust 
without condensation (either measured or from the chemical balance), 
and set any negative values to zero. This difference is the potential 
mole fraction of the dilute exhaust that would be lost due to water 
condensation on a continuous basis.
    (D) Integrate the product of the molar flow rate of the dilute 
exhaust and the potential mole fraction of dilute exhaust lost, and 
divide by the totalized dilute exhaust molar flow over the test 
interval. This is the potential mole fraction of the dilute exhaust 
that would be lost due to water condensation over the entire test 
interval. Note that this assumes no re-evaporation. This value must be 
less than or equal to 0.005.
* * * * *

0
43. Section 1065.170 is amended by revising paragraph (c)(1)(vi) to 
read as follows:

Sec.  1065.170  Batch sampling for gaseous and PM constituents.

* * * * *
    (c) * * *
    (1) * * *
    (vi) Maintain a filter face velocity near 100 cm/s with less than 
5% of the recorded flow values exceeding 100 cm/s, unless you expect 
the net PM mass on the filter to exceed 400 [micro]g, assuming a 38 mm 
diameter filter stain area. Measure face velocity as the volumetric 
flow rate of the sample at the pressure upstream of the filter and 
temperature of the filter face as measured in Sec.  1065.140(e), 
divided by the filter's exposed area. You may use the exhaust stack or 
CVS tunnel pressure for the upstream pressure if the pressure drop 
through the PM sampler up to the filter is less than 2 kPa.
* * * * *

0
44. Section 1065.190 is amended by revising Table 1 in paragraph (d)(3) 
to read as follows:

Sec.  1065.190  PM-stabilization and weighing environments for 
gravimetric analysis.

* * * * *
    (d) * * *
    (3) * * *

       Table 1 of Sec.   1065.190--Dewpoint Tolerance as a Function of % PM Change and % Sulfuric Acid PM
----------------------------------------------------------------------------------------------------------------
 Expected sulfuric acid fraction of   0.5% PM mass   1% PM mass   2% PM mass
                 PM                            change                    change                   change
----------------------------------------------------------------------------------------------------------------
5%..................................  3 [deg]C....  6 [deg]C...  12 [deg]C
50%.................................  0.3 [deg]C..  0.6 [deg]C.  1.2 [deg]C
100%................................  0.15 [deg]C.  0.3 [deg]C.  0.6 [deg]C
----------------------------------------------------------------------------------------------------------------

* * * * *

Subpart C--[Amended]

0
45. Section 1065.205 is revised to read as follows:

Sec.  1065.205  Performance specifications for measurement instruments.

    Your test system as a whole must meet all the applicable 
calibrations, verifications, and test-validation criteria specified in 
subparts D and F of this part or subpart J of this part for using PEMS 
and for performing field testing. We recommend that your instruments 
meet the specifications in Table 1 of this section for all ranges you 
use for testing. We also recommend that you keep any documentation you 
receive from instrument manufacturers showing that your instruments 
meet the specifications in Table 1 of this section.
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[GRAPHIC] [TIFF OMITTED] TR15SE11.020

BILLING CODE 4910-59-C

0
46. Section 1065.220 is amended by revising paragraph (a) introductory 
text and adding paragraph (a)(1)(iii) to read as follows:

[[Page 57442]]

Sec.  1065.220  Fuel flow meter.

    (a) Application. You may use fuel flow in combination with a 
chemical balance of fuel, inlet air, and raw exhaust to calculate raw 
exhaust flow as described in Sec.  1065.655(e), as follows:
    (1) * * *
    (iii) For calculating the dilution air flow for background 
correction as described in Sec.  1065.667.
* * * * *

0
47. Section 1065.225 is amended by revising paragraph (a) introductory 
text and adding paragraphs (a)(1)(iii) and (a)(1)(iv) to read as 
follows:

Sec.  1065.225  Intake-air flow meter.

* * * * *
    (a) Application. You may use an intake-air flow meter in 
combination with a chemical balance of fuel, inlet air, and raw exhaust 
to calculate raw exhaust flow as described in Sec.  1065.655(e) and 
(f), as follows:
    (1) * * *
    (iii) For validating minimum dilution ratio for PM batch sampling 
as described in Sec.  1065.546.
    (iv) For calculating the dilution air flow for background 
correction as described in Sec.  1065.667.
* * * * *

0
48. Section 1065.250 is revised to read as follows:

Sec.  1065.250  Nondispersive infrared analyzer.

    (a) Application. Use a nondispersive infrared (NDIR) analyzer to 
measure CO and CO2 concentrations in raw or diluted exhaust 
for either batch or continuous sampling.
    (b) Component requirements. We recommend that you use an NDIR 
analyzer that meets the specifications in Table 1 of Sec.  1065.205. 
Note that your NDIR-based system must meet the calibration and 
verifications in Sec. Sec.  1065.350 and 1065.355 and it must also meet 
the linearity verification in Sec.  1065.307. You may use an NDIR 
analyzer that has compensation algorithms that are functions of other 
gaseous measurements and the engine's known or assumed fuel properties. 
The target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias.

0
49. Section 1065.260 is revised to read as follows:

Sec.  1065.260  Flame-ionization detector.

    (a) Application. Use a flame-ionization detector (FID) analyzer to 
measure hydrocarbon concentrations in raw or diluted exhaust for either 
batch or continuous sampling. Determine hydrocarbon concentrations on a 
carbon number basis of one, C1. For measuring THC or THCE 
you must use a FID analyzer. For measuring CH4 you must meet 
the requirements of paragraph (f) of this section. See subpart I of 
this part for special provisions that apply to measuring hydrocarbons 
when testing with oxygenated fuels.
    (b) Component requirements. We recommend that you use a FID 
analyzer that meets the specifications in Table 1 of Sec.  1065.205. 
Note that your FID-based system for measuring THC, THCE, or 
CH4 must meet all the verifications for hydrocarbon 
measurement in subpart D of this part, and it must also meet the 
linearity verification in Sec.  1065.307. You may use a FID analyzer 
that has compensation algorithms that are functions of other gaseous 
measurements and the engine's known or assumed fuel properties. The 
target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias.
    (c) Heated FID analyzers. For measuring THC or THCE from 
compression-ignition engines, two-stroke spark-ignition engines, and 
four-stroke spark-ignition engines below 19 kW, you must use heated FID 
analyzers that maintain all surfaces that are exposed to emissions at a 
temperature of (191 11) [deg]C.
    (d) FID fuel and burner air. Use FID fuel and burner air that meet 
the specifications of Sec.  1065.750. Do not allow the FID fuel and 
burner air to mix before entering the FID analyzer to ensure that the 
FID analyzer operates with a diffusion flame and not a premixed flame.
    (e) NMHC. For demonstrating compliance with NMHC standards, you may 
either measure THC and CH4 and determine NMHC as described 
in Sec.  1065.660(b)(2) or (3), or you may measure THC and determine 
NMHC as described in Sec.  1065.660(b)(1).
    (f) CH4. For reporting CH4 or for demonstrating 
compliance with CH4 standards, you may use a FID analyzer 
with a nonmethane cutter as described in Sec.  1065.265 or you may use 
a GC-FID as described in Sec.  1065.267. Determine CH4 as 
described in Sec.  1065.660(c).

0
50. Section 1065.265 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.265  Nonmethane cutter.

* * * * *
    (b) System performance. Determine nonmethane-cutter performance as 
described in Sec.  1065.365 and use the results to calculate 
CH4 or NMHC emissions in Sec.  1065.660.
* * * * *

0
51. Section 1065.267 is revised to read as follows:

Sec.  1065.267  Gas chromatograph with a flame ionization detector.

    (a) Application. You may use a gas chromatograph with a flame 
ionization detector (GC-FID) to measure CH4 concentrations 
of diluted exhaust for batch sampling. While you may also use a 
nonmethane cutter to measure CH4, as described in Sec.  
1065.265, use a reference procedure based on a gas chromatograph for 
comparison with any proposed alternate measurement procedure under 
Sec.  1065.10.
    (b) Component requirements. We recommend that you use a GC-FID that 
meets the specifications in Table 1 of Sec.  1065.205, and it must also 
meet the linearity verification in Sec.  1065.307.

0
52. Section 1065.270 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.270  Chemiluminescent detector.

* * * * *
    (b) Component requirements. We recommend that you use a CLD that 
meets the specifications in Table 1 of Sec.  1065.205. Note that your 
CLD-based system must meet the quench verification in Sec.  1065.370 
and it must also meet the linearity verification in Sec.  1065.307. You 
may use a heated or unheated CLD, and you may use a CLD that operates 
at atmospheric pressure or under a vacuum. You may use a CLD that has 
compensation algorithms that are functions of other gaseous 
measurements and the engine's known or assumed fuel properties. The 
target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias.
* * * * *
0
53. Section 1065.272 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.272  N2O measurement devices.

* * * * *
    (b) Component requirements. We recommend that you use an NDUV 
analyzer that meets the specifications in Table 1 of Sec.  1065.205. 
Note that your NDUV-based system must meet the verifications in Sec.  
1065.372 and it must also meet the linearity verification in Sec.  
1065.307. You may use a NDUV analyzer that has compensation algorithms 
that are functions of other gaseous measurements and the engine's known 
or assumed fuel properties. The target value for any compensation 
algorithm is 0% (that is, no bias high and no bias low), regardless of 
the uncompensated signal's bias.
* * * * *

[[Page 57443]]

0
54. Section 1065.275 is amended by revising paragraphs (b) and (c) to 
read as follows:

Sec.  1065.275  N2O measurement devices.

* * * * *
    (b) Instrument types. You may use any of the following analyzers to 
measure N2O:
    (1) Nondispersive infrared (NDIR) analyzer. You may use an NDIR 
analyzer that has compensation algorithms that are functions of other 
gaseous measurements and the engine's known or assumed fuel properties. 
The target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias.
    (2) Fourier transform infrared (FTIR) analyzer. You may use an FTIR 
analyzer that has compensation algorithms that are functions of other 
gaseous measurements and the engine's known or assumed fuel properties. 
The target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias. 
Use appropriate analytical procedures for interpretation of infrared 
spectra. For example, EPA Test Method 320 is considered a valid method 
for spectral interpretation (see http://www.epa.gov/ttn/emc/methods/method320.html).
    (3) Laser infrared analyzer. You may use a laser infrared analyzer 
that has compensation algorithms that are functions of other gaseous 
measurements and the engine's known or assumed fuel properties. The 
target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias. 
Examples of laser infrared analyzers are pulsed-mode high-resolution 
narrow band mid-infrared analyzers, and modulated continuous wave high-
resolution narrow band mid-infrared analyzers.
    (4) Photoacoustic analyzer. You may use a photoacoustic analyzer 
that has compensation algorithms that are functions of other gaseous 
measurements. The target value for any compensation algorithm is 0% 
(that is, no bias high and no bias low), regardless of the 
uncompensated signal's bias. Use an optical wheel configuration that 
gives analytical priority to measurement of the least stable components 
in the sample. Select a sample integration time of at least 5 seconds. 
Take into account sample chamber and sample line volumes when 
determining flush times for your instrument.
    (5) Gas chromatograph analyzer. You may use a gas chromatograph 
with an electron-capture detector (GC-ECD) to measure N2O 
concentrations of diluted exhaust for batch sampling.
    (i) You may use a packed or porous layer open tubular (PLOT) column 
phase of suitable polarity and length to achieve adequate resolution of 
the N2O peak for analysis. Examples of acceptable columns 
are a PLOT column consisting of bonded polystyrene-divinylbenzene or a 
Porapack Q packed column. Take the column temperature profile and 
carrier gas selection into consideration when setting up your method to 
achieve adequate N2O peak resolution.
    (ii) Use good engineering judgment to zero your instrument and 
correct for drift. You do not need to follow the specific procedures in 
Sec. Sec.  1065.530 and 1065.550(b) that would otherwise apply. For 
example, you may perform a span gas measurement before and after sample 
analysis without zeroing and use the average area counts of the pre-
span and post-span measurements to generate a response factor (area 
counts/span gas concentration), which you then multiply by the area 
counts from your sample to generate the sample concentration.
    (c) Interference verification. Perform interference verification 
for NDIR, FTIR, laser infrared analyzers, and photoacoustic analyzers 
using the procedures of Sec.  1065.375. Interference verification is 
not required for GC-ECD. Certain interference gases can positively 
interfere with NDIR, FTIR, and photoacoustic analyzers by causing a 
response similar to N2O. When running the interference 
verification for these analyzers, use interference gases as follows:
    (1) The interference gases for NDIR analyzers are CO, 
CO2, H2O, CH4, and SO2. 
Note that interference species, with the exception of H2O, 
are dependent on the N2O infrared absorption band chosen by 
the instrument manufacturer. For each analyzer determine the 
N2O infrared absorption band. For each N2O 
infrared absorption band, use good engineering judgment to determine 
which interference gases to use in the verification.
    (2) Use good engineering judgment to determine interference gases 
for FTIR, and laser infrared analyzers. Note that interference species, 
with the exception of H2O, are dependent on the 
N2O infrared absorption band chosen by the instrument 
manufacturer. For each analyzer determine the N2O infrared 
absorption band. For each N2O infrared absorption band, use 
good engineering judgment to determine interference gases to use in the 
verification.
    (3) The interference gases for photoacoustic analyzers are CO, 
CO2, and H2O.

0
55. Section 1065.280 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.280  Paramagnetic and magnetopneumatic O2 detection 
analyzers.

* * * * *
    (b) Component requirements. We recommend that you use a PMD or MPD 
analyzer that meets the specifications in Table 1 of Sec.  1065.205. 
Note that it must meet the linearity verification in Sec.  1065.307. 
You may use a PMD or MPD that has compensation algorithms that are 
functions of other gaseous measurements and the engine's known or 
assumed fuel properties. The target value for any compensation 
algorithm is 0% (that is, no bias high and no bias low), regardless of 
the uncompensated signal's bias.

0
56. Section 1065.284 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.284  Zirconia (ZrO2) analyzer.

* * * * *
    (b) Component requirements. We recommend that you use a 
ZrO2 analyzer that meets the specifications in Table 1 of 
Sec.  1065.205. Note that your ZrO2-based system must meet 
the linearity verification in Sec.  1065.307. You may use a Zirconia 
analyzer that has compensation algorithms that are functions of other 
gaseous measurements and the engine's known or assumed fuel properties. 
The target value for any compensation algorithm is 0% (that is, no bias 
high and no bias low), regardless of the uncompensated signal's bias.

0
57. Section 1065.295 is amended by revising paragraph (b) to read as 
follows:

Sec.  1065.295  PM inertial balance for field-testing analysis.

* * * * *
    (b) Component requirements. We recommend that you use a balance 
that meets the specifications in Table 1 of Sec.  1065.205. Note that 
your balance-based system must meet the linearity verification in Sec.  
1065.307. If the balance uses an internal calibration process for 
routine spanning and linearity verifications, the process must be NIST-
traceable. You may use an inertial PM balance that has compensation 
algorithms that are functions of other gaseous measurements and the 
engine's known or assumed fuel properties. The target value for any 
compensation algorithm is 0% (that is, no bias high and no bias low), 
regardless of the uncompensated signal's bias.
* * * * *

[[Page 57444]]

Subpart D--[Amended]

0
58. Section 1065.303 is revised to read as follows:

Sec.  1065.303  Summary of required calibration and verifications.

    The following table summarizes the required and recommended 
calibrations and verifications described in this subpart and indicates 
when these have to be performed:

     Table 1 of Sec.   1065.303--Summary of Required Calibration and
                              Verifications
------------------------------------------------------------------------
    Type of calibration or
         verification                    Minimum frequency \a\
------------------------------------------------------------------------
Sec.   1065.305: Accuracy,     Accuracy: Not required, but recommended
 repeatability and noise.       for initial installation.
                               Repeatability: Not required, but
                                recommended for initial installation.
                               Noise: Not required, but recommended for
                                initial installation.
Sec.   1065.307: Linearity     Speed: Upon initial installation, within
 verification.                  370 days before testing and after major
                                maintenance.
                               Torque: Upon initial installation, within
                                370 days before testing and after major
                                maintenance.
                               Electrical power: Upon initial
                                installation, within 370 days before
                                testing and after major maintenance.
                               Fuel flow rate: Upon initial
                                installation, within 370 days before
                                testing, and after major maintenance.
                               Intake-air, dilution air, diluted
                                exhaust, and batch sampler flow rates:
                                Upon initial installation, within 370
                                days before testing and after major
                                maintenance, unless flow is verified by
                                propane check or by carbon or oxygen
                                balance.
                               Raw exhaust flow rate: Upon initial
                                installation, within 185 days before
                                testing and after major maintenance,
                                unless flow is verified by propane check
                                or by carbon or oxygen balance.
                               Gas dividers: Upon initial installation,
                                within 370 days before testing, and
                                after major maintenance.
                               Gas analyzers (unless otherwise noted):
                                Upon initial installation, within 35
                                days before testing and after major
                                maintenance.
                               FTIR and photoacoustic analyzers: Upon
                                initial installation, within 370 days
                                before testing and after major
                                maintenance.
                               GC-ECD: Upon initial installation and
                                after major maintenance.
                               PM balance: Upon initial installation,
                                within 370 days before testing and after
                                major maintenance.
                               Pressure, temperature, and dewpoint: Upon
                                initial installation, within 370 days
                                before testing and after major
                                maintenance.
Sec.   1065.308: Continuous    Upon initial installation or after system
 gas analyzer system response   modification that would affect response.
 and updating-recording
 verification--for gas
 analyzers not continuously
 compensated for other gas
 species.
Sec.   1065.309: Continuous    Upon initial installation or after system
 gas analyzer system-response   modification that would affect response.
 and updating-recording
 verification--for gas
 analyzers continuously
 compensated for other gas
 species.
Sec.   1065.310: Torque......  Upon initial installation and after major
                                maintenance.
Sec.   1065.315: Pressure,     Upon initial installation and after major
 temperature, dewpoint.         maintenance.
Sec.   1065.320: Fuel flow...  Upon initial installation and after major
                                maintenance.
Sec.   1065.325: Intake flow.  Upon initial installation and after major
                                maintenance.
Sec.   1065.330: Exhaust flow  Upon initial installation and after major
                                maintenance.
Sec.   1065.340: Diluted       Upon initial installation and after major
 exhaust flow (CVS).            maintenance.
Sec.   1065.341: CVS and       Upon initial installation, within 35 days
 batch sampler verification     before testing, and after major
 \b\.                           maintenance.
Sec.   1065.342 Sample dryer   For thermal chillers: upon installation
 verification.                  and after major maintenance.
                               For osmotic membranes; upon installation,
                                within 35 days of testing, and after
                                major maintenance.
Sec.   1065.345: Vacuum leak.  For laboratory testing: upon initial
                                installation of the sampling system,
                                within 8 hours before the start of the
                                first test interval of each duty-cycle
                                sequence, and after maintenance such as
                                pre-filter changes.
                               For field testing: after each
                                installation of the sampling system on
                                the vehicle, prior to the start of the
                                field test, and after maintenance such
                                as pre-filter changes.
Sec.   1065.350: CO2 NDIR H2O  Upon initial installation and after major
 interference.                  maintenance.
Sec.   1065.355: CO NDIR CO2   Upon initial installation and after major
 and H2O interference.          maintenance.
Sec.   1065.360: FID           Calibrate all FID analyzers: upon initial
 calibrationn.                  installation and after major
                                maintenance.
THC FID optimization, and THC  Optimize and determine CH4 response for
 FID verification.              THC FID analyzers: upon initial
                                installation and after major
                                maintenance.
                               Verify CH4 response for THC FID
                                analyzers: upon initial installation,
                                within 185 days before testing, and
                                after major maintenance.
Sec.   1065.362: Raw exhaust   For all FID analyzers: upon initial
 FID O2 interference.           installation, and after major
                                maintenance.
                               For THC FID analyzers: upon initial
                                installation, after major maintenance,
                                and after FID optimization according to
                                Sec.   1065.360.
Sec.   1065.365: Nonmethane    Upon initial installation, within 185
 cutter penetration.            days before testing, and after major
                                maintenance.
Sec.   1065.370: CLD CO2 and   Upon initial installation and after major
 H2O quench.                    maintenance.
Sec.   1065.372: NDUV HC and   Upon initial installation and after major
 H2O interference.              maintenance.
Sec.   1065.375: N2O analyzer  Upon initial installation and after major
 interference.                  maintenance.
Sec.   1065.376: Chiller NO2   Upon initial installation and after major
 penetration.                   maintenance.
Sec.   1065.378: NO2-to-NO     Upon initial installation, within 35 days
 converter conversion.          before testing, and after major
                                maintenance.

[[Page 57445]]

 
Sec.   1065.390: PM balance    Independent verification: upon initial
 and weighing.                  installation, within 370 days before
                                testing, and after major maintenance.
                               Zero, span, and reference sample
                                verifications: within 12 hours of
                                weighing, and after major maintenance.
Sec.   1065.395: Inertial PM   Independent verification: upon initial
 balance and weighing.          installation, within 370 days before
                                testing, and after major maintenance.
                               Other verifications: upon initial
                                installation and after major
                                maintenance.
------------------------------------------------------------------------
\a\ Perform calibrations and verifications more frequently, according to
  measurement system manufacturer instructions and good engineering
  judgment.
\b\ The CVS verification described in Sec.   1065.341 is not required
  for systems that agree within 2% based on a chemical
  balance of carbon or oxygen of the intake air, fuel, and diluted
  exhaust.

0
59. Section 1065.307 is amended by revising paragraph (a) and Table 1 
at the end of the section to read as follows:

Sec.  1065.307  Linearity verification.

    (a) Scope and frequency. Perform a linearity verification on each 
measurement system listed in Table 1 of this section at least as 
frequently as indicated in Table 1 of Sec.  1065.303, consistent with 
measurement system manufacturer recommendations and good engineering 
judgment. Note that this linearity verification may replace 
requirements we previously referred to as ``calibrations''. The intent 
of a linearity verification is to determine that a measurement system 
responds proportionally over the measurement range of interest. A 
linearity verification generally consists of introducing a series of at 
least 10 reference values to a measurement system. The measurement 
system quantifies each reference value. The measured values are then 
collectively compared to the reference values by using a least squares 
linear regression and the linearity criteria specified in Table 1 of 
this section.
* * * * *

              Table 1 of Sec.   1065.307--Measurement Systems That Require Linearity Verifications
----------------------------------------------------------------------------------------------------------------
                                                                       Linearity criteria
                                               -----------------------------------------------------------------
       Measurement system           Quantity        [verbarlm]
                                                   xmin(a1-1)+a0         a1              SEE             r\2\
                                                    [verbarlm]
----------------------------------------------------------------------------------------------------------------
Speed...........................      [fnof]n   = 0.990
                                                 [fnof]nmax                       [fnof]nmax
Torque..........................            T   = 0.990
                                                 Tmax.                            Tmax.
Electrical power................            P   = 0.990
                                                 Pmax.                            Pmax.
Fuel flow rate..................           mb   = 0.990
                                                 mbmax.                           mbmax
Intake-air flow rate............           nb   = 0.990
                                                 nbmax.                           nbmax.
Dilution air flow rate..........           nb   = 0.990
                                                 nbmax.                           nbmax.
Diluted exhaust flow rate.......           nb   = 0.990
                                                 nbmax.                           nbmax.
Raw exhaust flow rate...........           nb   = 0.990
                                                 nbmax.                           nbmax.
Batch sampler flow rates........           nb   = 0.990
                                                 nbmax.                           nbmax.
Gas dividers....................      x/xspan   = 0.990
                                                 xmax/xspan                       xmax/xspan
Gas analyzers for laboratory                x   = 0.998
 testing.                                        xbmax.                           xbmax.
Gas analyzers for field testing.            x   = 0.998
                                                 xbmax.                           xbmax.
PM balance......................            m   = 0.998
                                                 mmax.                            mbmax.
Pressures.......................            p   = 0.998
                                                 pbmax.                           pbmax.
Dewpoint for intake air, PM-             Tdew   = 0.998
 stabilization and balance                       Tdewmax                          Tdewmax
 environments.
Other dewpoint measurements.....         Tdew   = 0.998
                                                 Tdewmax                          Tdewmax
Analog-to-digital conversion of             T   = 0.998
 temperature signals.                            Tbmax                            Tmax
----------------------------------------------------------------------------------------------------------------

0
60. Section 1065.340 is amended by revising paragraphs (a) through (g), 
adding paragraph (h), and adding and reserving paragraph (i) before 
Figure 1 to read as follows:

Sec.  1065.340  Diluted exhaust flow (CVS) calibration.

    (a) Overview. This section describes how to calibrate flow meters 
for diluted exhaust constant-volume sampling (CVS) systems.
    (b) Scope and frequency. Perform this calibration while the flow 
meter is installed in its permanent position, except as allowed in 
paragraph (c) of this section. Perform this calibration after you 
change any part of the flow configuration upstream or downstream of the 
flow meter that may affect the flow-meter calibration. Perform this 
calibration upon initial CVS installation and whenever corrective 
action does not resolve a failure to meet the diluted exhaust flow 
verification (i.e., propane check) in Sec.  1065.341.
    (c) Ex-situ CFV and SSV calibration. You may remove a CFV or SSV 
from its permanent position for calibration as long as it meets the 
following requirements when installed in the CVS:
    (1) Upon installation of the CFV or SSV into the CVS, use good 
engineering judgment to verify that you have not introduced any leaks 
between the CVS inlet and the venturi.
    (2) After ex-situ venturi calibration, you must verify all venturi 
flow combinations for CFVs or at minimum of 10 flow points for an SSV 
using the propane check as described in Sec.  1065.341. Your propane 
check result for each venturi flow point may not exceed the tolerance 
in Sec.  1065.341(f)(5).
    (3) To verify your ex-situ calibration for a CVS with more than a 
single CFV, perform the following check to verify that there are no 
flow meter entrance effects that can prevent you from passing this 
verification.

[[Page 57446]]

    (i) Use a constant flow device like a CFO kit to deliver a constant 
flow of propane to the dilution tunnel.
    (ii) Measure hydrocarbon concentrations at a minimum of 10 separate 
flow rates for an SSV flow meter, or at all possible flow combinations 
for a CFV flow meter, while keeping the flow of propane constant. We 
recommend selecting CVS flow rates in a random order.
    (iii) Measure the concentration of hydrocarbon background in the 
dilution air at the beginning and end of this test. Subtract the 
average background concentration from each measurement at each flow 
point before performing the regression analysis in paragraph (c)(3)(iv) 
of this section.
    (iv) Perform a power regression using all the paired values of flow 
rate and corrected concentration to obtain a relationship in the form 
of y = a [middot] x \b\. Use concentration as the independent variable 
and flow rate as the dependent variable. For each data point, calculate 
the difference between the measured flow rate and the value represented 
by the curve fit. The difference at each point must be less than 1% of the appropriate regression value. The value of b must be 
between -1.005 and -0.995. If your results do not meet these limits, 
take corrective action consistent with Sec.  1065.341(a).
    (d) Reference flow meter. Calibrate a CVS flow meter using a 
reference flow meter such as a subsonic venturi flow meter, a long-
radius ASME/NIST flow nozzle, a smooth approach orifice, a laminar flow 
element, a set of critical flow venturis, or an ultrasonic flow meter. 
Use a reference flow meter that reports quantities that are NIST-
traceable within 1% uncertainty. Use this reference flow 
meter's response to flow as the reference value for CVS flow-meter 
calibration.
    (e) Configuration. Do not use an upstream screen or other 
restriction that could affect the flow ahead of the reference flow 
meter, unless the flow meter has been calibrated with such a 
restriction.
    (f) PDP calibration. Calibrate a positive-displacement pump (PDP) 
to determine a flow-versus-PDP speed equation that accounts for flow 
leakage across sealing surfaces in the PDP as a function of PDP inlet 
pressure. Determine unique equation coefficients for each speed at 
which you operate the PDP. Calibrate a PDP flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Leaks between the calibration flow meter and the PDP must be 
less than 0.3% of the total flow at the lowest calibrated flow point; 
for example, at the highest restriction and lowest PDP-speed point.
    (3) While the PDP operates, maintain a constant temperature at the 
PDP inlet within 2% of the mean absolute inlet temperature, 
Tin.
    (4) Set the PDP speed to the first speed point at which you intend 
to calibrate.
    (5) Set the variable restrictor to its wide-open position.
    (6) Operate the PDP for at least 3 min to stabilize the system. 
Continue operating the PDP and record the mean values of at least 30 
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter, 
nref. This may include several measurements of different 
quantities, such as reference meter pressures and temperatures, for 
calculating nref.
    (ii) The mean temperature at the PDP inlet, Tin.
    (iii) The mean static absolute pressure at the PDP inlet, 
pin.
    (iv) The mean static absolute pressure at the PDP outlet, 
pout.
    HERE
    (v) The mean PDP speed, fnPDP.
    HERE
    (7) Incrementally close the restrictor valve to decrease the 
absolute pressure at the inlet to the PDP, pin.
    (8) Repeat the steps in paragraphs (e)(6) and (7) of this section 
to record data at a minimum of six restrictor positions ranging from 
the wide open restrictor position to the minimum expected pressure at 
the PDP inlet.
    (9) Calibrate the PDP by using the collected data and the equations 
in Sec.  1065.640.
    (10) Repeat the steps in paragraphs (e)(6) through (9) of this 
section for each speed at which you operate the PDP.
    (11) Use the equations in Sec.  1065.642 to determine the PDP flow 
equation for emission testing.
    (12) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec.  1065.341.
    (13) Do not use the PDP below the lowest inlet pressure tested 
during calibration.
    (g) CFV calibration. Calibrate a critical-flow venturi (CFV) to 
verify its discharge coefficient, Cd, at the lowest expected 
static differential pressure between the CFV inlet and outlet. 
Calibrate a CFV flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and 
the CFV are less than 0.3% of the total flow at the highest 
restriction.
    (3) Start the blower downstream of the CFV.
    (4) While the CFV operates, maintain a constant temperature at the 
CFV inlet within 2% of the mean absolute inlet temperature, 
Tin.
    (5) Set the variable restrictor to its wide-open position. Instead 
of a variable restrictor, you may alternately vary the pressure 
downstream of the CFV by varying blower speed or by introducing a 
controlled leak. Note that some blowers have limitations on nonloaded 
conditions.
    (6) Operate the CFV for at least 3 min to stabilize the system. 
Continue operating the CFV and record the mean values of at least 30 
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter, 
nref. This may include several measurements of different 
quantities, such as reference meter pressures and temperatures, for 
calculating nref.
    (ii) The mean dewpoint of the calibration air, Tdew. See 
Sec.  1065.640 for permissible assumptions during emission 
measurements.
    (iii) The mean temperature at the venturi inlet, Tin.
    (iv) The mean static absolute pressure at the venturi inlet, 
pin.
    (v) The mean static differential pressure between the CFV inlet and 
the CFV outlet, [Delta]pCFV.
    (7) Incrementally close the restrictor valve or decrease the 
downstream pressure to decrease the differential pressure across the 
CFV, [Delta]pCFV.
    (8) Repeat the steps in paragraphs (f)(6) and (7) of this section 
to record mean data at a minimum of ten restrictor positions, such that 
you test the fullest practical range of [Delta]pCFV expected 
during testing. We do not require that you remove calibration 
components or CVS components to calibrate at the lowest possible 
restrictions.
    (9) Determine Cd and the lowest allowable pressure 
ratio, r, according to Sec.  1065.640.
    (10) Use Cd to determine CFV flow during an emission 
test. Do not use the CFV below the lowest allowed r, as determined in 
Sec.  1065.640.
    (11) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec.  1065.341.
    (12) If your CVS is configured to operate more than one CFV at a 
time in parallel, calibrate your CVS by one of the following:
    (i) Calibrate every combination of CFVs according to this section 
and Sec.  1065.640. Refer to Sec.  1065.642 for

[[Page 57447]]

instructions on calculating flow rates for this option.
    (ii) Calibrate each CFV according to this section and Sec.  
1065.640. Refer to Sec.  1065.642 for instructions on calculating flow 
rates for this option.
    (h) SSV calibration. Calibrate a subsonic venturi (SSV) to 
determine its calibration coefficient, Cd, for the expected 
range of inlet pressures. Calibrate an SSV flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and 
the SSV are less than 0.3% of the total flow at the highest 
restriction.
    (3) Start the blower downstream of the SSV.
    (4) While the SSV operates, maintain a constant temperature at the 
SSV inlet within 2% of the mean absolute inlet temperature, 
Tin.
    (5) Set the variable restrictor or variable-speed blower to a flow 
rate greater than the greatest flow rate expected during testing. You 
may not extrapolate flow rates beyond calibrated values, so we 
recommend that you make sure the Reynolds number, Re#, at the SSV 
throat at the greatest calibrated flow rate is greater than the maximum 
Re# expected during testing.
    (6) Operate the SSV for at least 3 min to stabilize the system. 
Continue operating the SSV and record the mean of at least 30 seconds 
of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter nref. 
This may include several measurements of different quantities, such as 
reference meter pressures and temperatures, for calculating 
nref.
    (ii) Optionally, the mean dewpoint of the calibration air, 
Tdew. See Sec.  1065.640 for permissible assumptions.
    (iii) The mean temperature at the venturi inlet, Tin.
    (iv) The mean static absolute pressure at the venturi inlet, 
pin.
    (v) Static differential pressure between the static pressure at the 
venturi inlet and the static pressure at the venturi throat, 
[Delta]pssv.
    (7) Incrementally close the restrictor valve or decrease the blower 
speed to decrease the flow rate.
    (8) Repeat the steps in paragraphs (g)(6) and (7) of this section 
to record data at a minimum of ten flow rates.
    (9) Determine a functional form of Cd versus Re# by 
using the collected data and the equations in Sec.  1065.640.
    (10) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec.  1065.341 using the new 
Cd versus Re# equation.
    (11) Use the SSV only between the minimum and maximum calibrated 
flow rates.
    (12) Use the equations in Sec.  1065.642 to determine SSV flow 
during a test.
    (i) Ultrasonic flow meter calibration. [Reserved]
* * * * *

0
61. Section 1065.341 is amended by revising paragraphs (a)(5), (a)(6), 
and (f)(5) and adding paragraph (a)(7) to read as follows:

Sec.  1065.341  CVS and batch sampler verification (propane check).

    (a) * * *
    (5) Change in CVS calibration. Perform a calibration of the CVS 
flow meter as described in Sec.  1065.340.
    (6) Flow meter entrance effects. Inspect the CVS tunnel to 
determine whether the entrance effects from the piping configuration 
upstream of the flow meter adversely affect the flow measurement.
    (7) Other problems with the CVS or sampling verification hardware 
or software. Inspect the CVS system, CVS verification hardware, and 
software for discrepancies.
* * * * *
    (f) * * *
    (5) Subtract the reference C3H8 mass from the 
calculated mass. If this difference is within 2% of the 
reference mass, the CVS passes this verification. If not, take 
corrective action as described in paragraph (a) of this section.
* * * * *

0
62. Section 1065.350 is amended by revising paragraph (d)(7) to read as 
follows:

Sec.  1065.350  H2O interference verification for CO2 NDIR analyzers.

* * * * *
    (d) * * *
    (7) While the analyzer measures the sample's concentration, record 
30 seconds of sampled data. Calculate the arithmetic mean of this data. 
The analyzer meets the interference verification if this value is 
within (0.0  0.4) mmol/mol.
* * * * *

0
63. Section 1065.360 is amended by revising paragraph (e) introductory 
text to read as follows:

Sec.  1065.360  FID optimization and verification.

* * * * *
    (e) THC FID methane (CH4) response verification. This procedure is 
only for FID analyzers that measure THC. If the value of 
RFCH4[THC-FID] from paragraph (d) of this section is within 
5% of its most recent previously determined value, the THC 
FID passes the methane response verification. For example, if the most 
recent previous value for RFCH4[THC-FID] was 1.05 and it 
changed by 0.05 to become 1.10 or it changed by -0.05 to 
become 1.00, either case would be acceptable because 4.8% 
is less than 5%. Verify RFCH4[THC-FID] as 
follows:
* * * * *

0
64. Section 1065.370 is amended by revising paragraph (g)(1) to read as 
follows:

Sec.  1065.370  CLD CO2 and H2O quench verification.

* * * * *
    (g) * * *
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculation procedures, the combined CO2 and H2O 
interference for your NOX CLD analyzer always affects your 
brake-specific NOX emission results within no more than 
1% of the applicable NOX standard. If you 
certify to a combined emission standard (such as a NOX + 
NMHC standard), scale your NOX results to the combined 
standard based on the measured results (after incorporating 
deterioration factors, if applicable). For example, if your final 
NOX + NMHC value is half of the emission standard, double 
the NOX result to estimate the level of NOX 
emissions corresponding to the applicable standard.
* * * * *

0
65. Section 1065.372 is amended by revising paragraph (e)(1) to read as 
follows:

Sec.  1065.372  NDUV analyzer HC and H2O interference verification.

* * * * *
    (e) * * *
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculation procedures, the combined HC and H2O interference 
for your NOX NDUV analyzer always affects your brake-
specific NOX emission results by less than 0.5% of the 
applicable NOX standard.
* * * * *

0
66. Section 1065.378 is amended by revising paragraph (d)(3)(iv) to 
read as follows:

Sec.  1065.378  NO2-to-NO converter conversion verification.

* * * * *
    (d) * * *
    (3) * * *
    (iv) Switch the ozonator on and adjust the ozone generation rate so 
the NO

[[Page 57448]]

measured by the analyzer is 20 percent of xNOref or a value 
which would simulate the maximum concentration of NO2 
expected during testing, while maintaining at least 10 percent 
unreacted NO. This ensures that the ozonator is generating 
NO2 at the maximum concentration expected during testing. 
Record the concentration of NO by calculating the mean of 30 seconds of 
sampled data from the analyzer and record this value as 
xNOmeas.
* * * * *

Subpart F--[Amended]

0
67. Section 1065.510 is amended as follows:
0
a. By revising paragraphs (a) introductory text, (b)(5)(i), and (b)(6).
0
b. By adding paragraph (b)(7).
0
c. By revising paragraphs (c)(2), (d)(5), (f)(3), (f)(5), and (g).
0
d. By adding paragraphs (c)(4) and (h) to read as follows:

Sec.  1065.510  Engine mapping.

    (a) Applicability, scope, and frequency. An engine map is a data 
set that consists of a series of paired data points that represent the 
maximum brake torque versus engine speed, measured at the engine's 
primary output shaft. Map your engine if the standard-setting part 
requires engine mapping to generate a duty cycle for your engine 
configuration. Map your engine while it is connected to a dynamometer 
or other device that can absorb work output from the engine's primary 
output shaft according to Sec.  1065.110. To establish speed and torque 
values for mapping, we generally recommend that you stabilize an engine 
for at least 15 seconds at each setpoint and record the mean feedback 
speed and torque of the last (4 to 6) seconds. Configure any auxiliary 
work inputs and outputs such as hybrid, turbo-compounding, or 
thermoelectric systems to represent their in-use configurations, and 
use the same configuration for emission testing. See Figure 1 of Sec.  
1065.210. This may involve configuring initial states of charge and 
rates and times of auxiliary-work inputs and outputs. We recommend that 
you contact the Designated Compliance Officer before testing to 
determine how you should configure any auxiliary-work inputs and 
outputs. Use the most recent engine map to transform a normalized duty 
cycle from the standard-setting part to a reference duty cycle specific 
to your engine. Normalized duty cycles are specified in the standard-
setting part. You may update an engine map at any time by repeating the 
engine-mapping procedure. You must map or re-map an engine before a 
test if any of the following apply:
* * * * *
    (b) * * *
    (5) * * *
    (i) For any engine subject only to steady-state duty cycles, you 
may perform an engine map by using discrete speeds. Select at least 20 
evenly spaced setpoints from 95% of warm idle speed to the highest 
speed above maximum power at which 50% of maximum power occurs. We 
refer to this 50% speed as the check point speed as described in 
paragraph (b)(5)(iii) of this section. At each setpoint, stabilize 
speed and allow torque to stabilize. Record the mean speed and torque 
at each setpoint. Use linear interpolation to determine intermediate 
speeds and torques. Use this series of speeds and torques to generate 
the power map as described in paragraph (e) of this section.
* * * * *
    (6) Use one of the following methods to determine warm high-idle 
speed for engines with a high-speed governor if they are subject to 
transient testing with a duty cycle that includes reference speed 
values above 100%:
    (i) You may use a manufacturer-declared warm high-idle speed if the 
engine is electronically governed. For engines with a high-speed 
governor that shuts off torque output at a manufacturer-specified speed 
and reactivates at a lower manufacturer-specified speed (such as 
engines that use ignition cut-off for governing), declare the middle of 
the specified speed range as the warm high-idle speed.
    (ii) Measure the warm high-idle speed using the following 
procedure:
    (A) Set operator demand to maximum and use the dynamometer to 
target zero torque on the engine's primary output shaft. If the mean 
feedback torque is within 1% of Tmax mapped, you 
may use the observed mean feedback speed at that point as the measured 
warm high-idle speed.
    (B) If the engine is unstable as a result of in-use production 
components (such as engines that use ignition cut-off for governing, as 
opposed to unstable dynamometer operation), you must use the mean 
feedback speed from paragraph (b)(6)(ii)(A) of this section as the 
measured warm high-idle speed. The engine is considered unstable if any 
of the 1 Hz speed feedback values are not within 2% of the 
calculated mean feedback speed. We recommend that you determine the 
mean as the value representing the midpoint between the observed 
maximum and minimum recorded feedback speed.
    (C) If your dynamometer is not capable of achieving a mean feedback 
torque within 1% of Tmax mapped, operate the 
engine at a second point with operator demand set to maximum with the 
dynamometer set to target a torque equal to the recorded mean feedback 
torque on the previous point plus 20% of Tmax mapped. Use 
this data point and the data point from paragraph (b)(6)(ii)(A) of this 
section to extrapolate the engine speed where torque is equal to zero.
    (D) You may use a manufacturer-declared Tmax instead of 
the measured Tmax mapped. If you do this, or if you are able 
to determine mean feedback speed as described in paragraphs 
(b)(6)(ii)(A) and (B) of this section, you may measure the warm high-
idle speed before running the speed sweep specified in paragraph (b)(5) 
of this section.
    (7) For engines with a low-speed governor, if a nonzero idle torque 
is representative of in-use operation, operate the engine at warm idle 
with the manufacturer-declared idle torque. Set the operator demand to 
minimum, use the dynamometer to target the declared idle torque, and 
allow the engine to govern the speed. Measure this speed and use it as 
the warm idle speed for cycle generation in Sec.  1065.512. We 
recommend recording at least 30 values of speed and using the mean of 
those values. If you identify multiple warm idle torques under 
paragraph (f)(4)(i) of this section, measure the warm idle speed at 
each torque. You may map the idle governor at multiple load levels and 
use this map to determine the measured warm idle speed at the declared 
idle torque(s).
    (c) * * *
    (2) Map the amount of negative torque required to motor the engine 
by repeating paragraph (b) of this section with minimum operator 
demand. You may start the negative torque map at either the minimum or 
maximum speed from paragraph (b) of this section.
* * * * *
    (4) For engines with an electric hybrid system, you may create a 
negative torque map that would include the full negative torque of the 
electric hybrid system, so operator demand will be at a minimum when 
the reference duty cycle specifies negative torque values.
    (d) * * *
    (5) Perform one of the following:
    (i) For constant-speed engines subject only to steady-state 
testing, you may perform an engine map by using a series of discrete 
torques. Select at least five evenly spaced torque setpoints from no-

[[Page 57449]]

load to 80% of the manufacturer-declared test torque or to a torque 
derived from your published maximum power level if the declared test 
torque is unavailable. Starting at the 80% torque point, select 
setpoints in 2.5% intervals, stopping at the endpoint torque. The 
endpoint torque is defined as the first discrete mapped torque value 
greater than the torque at maximum observed power where the engine 
outputs 90% of the maximum observed power; or the torque when engine 
stall has been determined using good engineering judgment (i.e. sudden 
deceleration of engine speed while adding torque). You may continue 
mapping at higher torque setpoints. At each setpoint, allow torque and 
speed to stabilize. Record the mean feedback speed and torque at each 
setpoint. From this series of mean feedback speed and torque values, 
use linear interpolation to determine intermediate values. Use this 
series of mean feedback speeds and torques to generate the power map as 
described in paragraph (e) of this section.
    (ii) For any constant-speed engine, you may perform an engine map 
with a continuous torque sweep by continuing to record the mean 
feedback speed and torque at 1 Hz or more frequently. Use the 
dynamometer to increase torque. Increase the reference torque at a 
constant rate from no-load to the endpoint torque as defined in 
paragraph (d)(5)(i) of this section. You may continue mapping at higher 
torque setpoints. Unless the standard-setting part specifies otherwise, 
target a torque sweep rate equal to the manufacturer-declared test 
torque (or a torque derived from your published power level if the 
declared test torque is not known) divided by 180 s. Stop recording 
after you complete the sweep. Verify that the average torque sweep rate 
over the entire map is within 7% of the target torque sweep 
rate. Use linear interpolation to determine intermediate values from 
this series of mean feedback speed and torque values. Use this series 
of mean feedback speeds and torques to generate the power map as 
described in paragraph (e) of this section.
    (iii) For electric power generation applications in which normal 
engine operation is limited to a specific speed range, map the engine 
with two points as described in this paragraph (d)(5)(iii). After 
stabilizing at the no-load governed speed in paragraph (d)(4) of this 
section, record the mean feedback speed and torque. Continue to operate 
the engine with the governor or simulated governor controlling engine 
speed using operator demand, and control the dynamometer to target a 
speed of 97.5% of the recorded mean no-load governed speed. If the in-
use performance class of the electric power generation application is 
known, you may use those values in place of 97.5% (e.g., for ISO 8528-5 
G3 Performance Class, the steady-state frequency band is less than or 
equal to 0.5%, so use 99.75% instead of 97.5%). Allow speed and torque 
to stabilize. Record the mean feedback speed and torque. Record the 
target speed. The absolute value of the speed error (the mean feedback 
speed minus the target speed) must be no greater than 20% of the 
difference between the recorded mean no-load governed speed and the 
target speed. From this series of two mean feedback speed and torque 
values, use linear interpolation to determine intermediate values. Use 
this series of two mean feedback speeds and torques to generate a power 
map as described in paragraph (e) of this section. Note that the 
measured maximum test torque determined in Sec.  1065.610(b)(1), will 
be the mean feedback torque recorded on the second point.
* * * * *
    (f) * * *
    (3) Optional declared speeds. You may use declared speeds instead 
of measured speeds as follows:
    (i) You may use a declared value for maximum test speed for 
variable-speed engines if it is within (97.5 to 102.5) % of the 
corresponding measured value. You may use a higher declared speed if 
the length of the ``vector'' at the declared speed is within 2% of the 
length of the ``vector'' at the measured value. The term vector refers 
to the square root of the sum of normalized engine speed squared and 
the normalized full-load power (at that speed) squared, consistent with 
the calculations in Sec.  1065.610.
    (ii) You may use a declared value for intermediate, ``A'', ``B'', 
or ``C'' speeds for steady-state tests if the declared value is within 
(97.5 to 102.5)% of the corresponding measured value.
    (iii) For electronically governed engines, you may use a declared 
warm high-idle speed for calculating the alternate maximum test speed 
as specified in Sec.  1065.610.
* * * * *
    (5) Optional declared torques. (i) For variable-speed engines you 
may declare a maximum torque over the engine operating range. You may 
use the declared value for measuring warm high-idle speed as specified 
in this section.
    (ii) For constant-speed engines you may declare a maximum test 
torque. You may use the declared value for cycle generation if it is 
within (95 to 100) % of the measured value.
    (g) Mapping variable-speed engines with an electric hybrid system. 
Map variable-speed engines that include electric hybrid systems as 
described in this paragraph (g). You may ask to apply these provisions 
to other types of hybrid engines, consistent with good engineering 
judgment. However, do not use this procedure for engines used in hybrid 
vehicles where the hybrid system is certified as part of the vehicle 
rather than the engine. Follow the steps for mapping a variable-speed 
engine as given in paragraph (b)(5) of this section except as noted in 
this paragraph (g). You must generate one engine map with the hybrid 
system inactive as described in paragraph (g)(1) of this section, and a 
separate map with the hybrid system active as described in paragraph 
(g)(2) of this section. See the standard-setting part to determine how 
to use these maps. The map with the system inactive is typically used 
to generate steady-state duty cycles, but may also be used to generate 
transient cycles, such as those that do not involve engine motoring. 
This hybrid-inactive map is also used for generating the hybrid-active 
map. The hybrid-active map is typically used to generate transient duty 
cycles that involve engine motoring.
    (1) Prepare the engine for mapping by either deactivating the 
hybrid system or by operating the engine as specified in paragraph 
(b)(4) of this section and remaining at this condition until the 
rechargeable energy storage system (RESS) is depleted. Once the hybrid 
has been disabled or the RESS is depleted, perform an engine map as 
specified in paragraph (b)(5) of this section. If the RESS was depleted 
instead of deactivated, ensure that instantaneous power from the RESS 
remains less than 2% of the instantaneous measured power from the 
engine (or engine-hybrid system) at all engine speeds.
    (2) The purpose of the mapping procedure in this paragraph (g) is 
to determine the maximum torque available at each speed, such as what 
might occur during transient operation with a fully charged RESS. Use 
one of the following methods to generate a hybrid-active map:
    (i) Perform an engine map by using a series of continuous sweeps to 
cover the engine's full range of operating speeds. Prepare the engine 
for hybrid-active mapping by ensuring that the RESS state of charge is 
representative of normal operation. Perform the sweep as specified in 
paragraph (b)(5)(ii) of this section, but stop the sweep to charge the 
RESS when the power measured from the RESS drops below the expected

[[Page 57450]]

maximum power from the RESS by more than 2% of total system power 
(including engine and RESS power). Unless good engineering judgment 
indicates otherwise, assume that the expected maximum power from the 
RESS is equal to the measured RESS power at the start of the sweep 
segment. For example, if the 3-second rolling average of total engine-
RESS power is 200 kW and the power from the RESS at the beginning of 
the sweep segment is 50 kW, once the power from the RESS reaches 46 kW, 
stop the sweep to charge the RESS. Note that this assumption is not 
valid where the hybrid motor is torque-limited. Calculate total system 
power as a 3-second rolling average of instantaneous total system 
power. After each charging event, stabilize the engine for 15 seconds 
at the speed at which you ended the previous segment with operator 
demand set to maximum before continuing the sweep from that speed. 
Repeat the cycle of charging, mapping, and recharging until you have 
completed the engine map. You may shut down the system or include other 
operation between segments to be consistent with the intent of this 
paragraph (g)(2)(i). For example, for systems in which continuous 
charging and discharging can overheat batteries to an extent that 
affects performance, you may operate the engine at zero power from the 
RESS for enough time after the system is recharged to allow the 
batteries to cool. Use good engineering judgment to smooth the torque 
curve to eliminate discontinuities between map intervals.
    (ii) Perform an engine map by using discrete speeds. Select map 
setpoints at intervals defined by the ranges of engine speed being 
mapped. From 95% of warm idle speed to 90% of the expected maximum test 
speed, select setpoints that result in a minimum of 13 equally spaced 
speed setpoints. From 90% to 110% of expected maximum test speed, 
select setpoints in equally spaced intervals that are nominally 2% of 
expected maximum test speed. Above 110% of expected maximum test speed, 
select setpoints based on the same speed intervals used for mapping 
from 95% warm idle speed to 90% maximum test speed. You may stop 
mapping at the highest speed above maximum power at which 50% of 
maximum power occurs. We refer to the speed at 50% power as the check 
point speed as described in paragraph (b)(5)(iii) of this section. 
Stabilize engine speed at each setpoint, targeting a torque value at 
70% of peak torque at that speed without hybrid-assist. Make sure the 
engine is fully warmed up and the RESS state of charge is within the 
normal operating range. Snap the operator demand to maximum, operate 
the engine there for at least 10 seconds, and record the 3-second 
rolling average feedback speed and torque at 1 Hz or higher. Record the 
peak 3-second average torque and 3-second average speed at that point. 
Use linear interpolation to determine intermediate speeds and torques. 
Follow Sec.  1065.610(a) to calculate the maximum test speed. Verify 
that the measured maximum test speed falls in the range from 92 to 108% 
of the estimated maximum test speed. If the measured maximum test speed 
does not fall in this range, rerun the map using the measured value of 
maximum test speed.
    (h) Other mapping procedures. You may use other mapping procedures 
if you believe the procedures specified in this section are unsafe or 
unrepresentative for your engine. Any alternate techniques you use must 
satisfy the intent of the specified mapping procedures, which is to 
determine the maximum available torque at all engine speeds that occur 
during a duty cycle. Identify any deviations from this section's 
mapping procedures when you submit data to us.

0
68. Section 1065.514 is amended by revising paragraph (f)(3) to read as 
follows:

Sec.  1065.514  Cycle-validation criteria for operation over specified 
duty cycles.

* * * * *
    (f) * * *
    (3) For discrete-mode steady-state testing, apply cycle-validation 
criteria by treating the sampling periods from the series of test modes 
as a continuous sampling period, analogous to ramped-modal testing and 
apply statistical criteria as described in paragraph (f)(1) or (f)(2) 
of this section. Note that if the gaseous and particulate test 
intervals are different periods of time, separate validations are 
required for the gaseous and particulate test intervals. Table 2 
follows:

               Table 2 of Sec.   1065.514--Default Statistical Criteria for Validating Duty Cycles
----------------------------------------------------------------------------------------------------------------
              Parameter                         Speed                    Torque                   Power
----------------------------------------------------------------------------------------------------------------
Slope, a1............................  0.950 = 0.970...............  >= 0.850...............  >= 0.910.
----------------------------------------------------------------------------------------------------------------

0
69. Section 1065.520 is amended by revising paragraph (g) introductory 
text, (g)(5)(i), (g)(7), and (g)(8) and adding paragraph (g)(9) to read 
as follows:

Sec.  1065.520  Pre-test verification procedures and pre-test data 
collection.

* * * * *
    (g) Verify the amount of nonmethane hydrocarbon contamination in 
the exhaust and background HC sampling systems within 8 hours before 
the start of the first test interval of each duty-cycle sequence for 
laboratory tests. You may verify the contamination of a background HC 
sampling system by reading the last bag fill and purge using zero gas. 
For any NMHC measurement system that involves separately measuring 
methane and subtracting it from a THC measurement or for any 
CH4 measurement system that uses an NMC, verify the amount 
of THC contamination using only the THC analyzer response. There is no 
need to operate any separate methane analyzer for this verification; 
however, you may measure and correct for THC contamination in the 
CH4 sample train for the cases where NMHC is determined by 
subtracting CH4 from THC or, where CH4 is 
determined, using an NMC as configured in Sec.  1065.365(d), (e), and 
(f); and using the calculations in Sec.  1065.660(b)(2). Perform this 
verification as follows:
* * * * *
    (5) * * *
    (i) For continuous sampling, record the mean THC concentration as 
overflow zero gas flows.
* * * * *
    (7) You may correct the measured initial THC concentration for 
drift as follows:
    (i) For batch and continuous HC analyzers, after determining the 
initial THC concentration, flow zero gas to the analyzer zero or sample 
port. When the

[[Page 57451]]

analyzer reading is stable, record the mean analyzer value.
    (ii) Flow span gas to the analyzer span or sample port. When the 
analyzer reading is stable, record the mean analyzer value.
    (iii) Use mean analyzer values from paragraphs (g)(2), (g)(3), 
(g)(7)(i), and (g)(7)(ii) of this section to correct the initial THC 
concentration recorded in paragraph (g)(6) of this section for drift, 
as described in Sec.  1065.550.
    (8) If any of the xTHC[THC-FID]init values exceed the 
greatest of the following values, determine the source of the 
contamination and take corrective action, such as purging the system 
during an additional preconditioning cycle or replacing contaminated 
portions:
    (i) 2% of the flow-weighted mean wet, net concentration expected at 
the HC (THC or NMHC) standard.
    (ii) 2% of the flow-weighted mean wet, net concentration of HC (THC 
or NMHC) measured during testing.
    (iii) 2 [mu]mol/mol.
    (9) If corrective action does not resolve the deficiency, you may 
request to use the contaminated system as an alternate procedure under 
Sec.  1065.10.
* * * * *

0
70. Section 1065.525 is amended by removing paragraph (c)(4) and 
revising paragraph (a) to read as follows.

Sec.  1065.525  Engine starting, restarting, and shutdown.

    (a) For test intervals that require emission sampling during engine 
starting, start the engine using one of the following methods:
    (1) Start the engine as recommended in the owners manual using a 
production starter motor or air-start system and either an adequately 
charged battery, a suitable power supply, or a suitable compressed air 
source.
    (2) Use the dynamometer to start the engine. To do this, motor the 
engine within  25% of its typical in-use cranking speed. 
Stop cranking within 1 second of starting the engine.
    (3) In the case of hybrid engines, activate the system such that 
the engine will start when its control algorithms determine that the 
engine should provide power instead of or in addition to power from the 
RESS. Unless we specify otherwise, engine starting throughout this part 
generally refers to this step of activating the system on hybrid 
engines, whether or not that causes the engine to start running.
* * * * *

0
71. Section 1065.530 is amended by revising paragraph (b)(13) to read 
as follows:

Sec.  1065.530  Emission test sequence.

* * * * *
    (b) * * *
    (13) Drain any accumulated condensate from the intake air system 
before starting a duty cycle, as described in Sec.  1065.125(e)(1). If 
engine and aftertreatment preconditioning cycles are run before the 
duty cycle, treat the preconditioning cycles and any associated soak 
period as part of the duty cycle for the purpose of opening drains and 
draining condensate. Note that you must close any intake air condensate 
drains that are not representative of those normally open during in-use 
operation.
* * * * *

0
72. Section 1065.546 is amended by revising paragraph (a) to read as 
follows:

Sec.  1065.546  Validation of minimum dilution ratio for PM batch 
sampling, and drift correction.

* * * * *
    (a) Determine minimum dilution ratio based on molar flow data. This 
involves determination of at least two of the following three 
quantities: Raw exhaust flow (or previously diluted flow), dilution air 
flow, and dilute exhaust flow. You may determine the raw exhaust flow 
rate based on the measured intake air or fuel flow rate and the raw 
exhaust chemical balance terms as given in Sec.  1065.655(e). You may 
determine the raw exhaust flow rate based on the measured intake air 
and dilute exhaust molar flow rates and the dilute exhaust chemical 
balance terms as given in Sec.  1065.655(f). You may alternatively 
estimate the molar raw exhaust flow rate based on intake air, fuel rate 
measurements, and fuel properties, consistent with good engineering 
judgment.
* * * * *

0
73. Section 1065.550 is amended by revising the section heading and 
paragraph (b) to read as follows:

Sec.  1065.550  Gas analyzer range validation and drift validation.

* * * * *
    (b) Drift validation and drift correction. Gas analyzer drift 
validation is required for all gaseous exhaust constituents for which 
an emission standard applies. It is also required for CO2 
even if there is no CO2 emission standard. It is not 
required for other gaseous exhaust constituents for which only a 
reporting requirement applies (such as CH4 and 
N2O).
    (1) Validate drift using one of the following methods:
    (i) For regulated exhaust constituents determined from the mass of 
a single component, perform drift validation based on the regulated 
constituent. For example, when NOX mass is determined with a 
dry sample measured with a CLD and the removed water is corrected based 
on measured CO2, CO, THC, and NOX concentrations, 
you must validate the calculated NOX value.
    (ii) For regulated exhaust constituents determined from the masses 
of multiple subcomponents, perform the drift validation based on either 
the regulated constituent or all the mass subcomponents. For example, 
when NOX is measured with separate NO and NO2 
analyzers, you must validate either the NOX value or both 
the NO and NO2 values.
    (iii) For regulated exhaust constituents determined from the 
concentrations of multiple gaseous emission subcomponents prior to 
performing mass calculations, perform drift validation on the regulated 
constituent. You may not validate the concentration subcomponents 
(e.g., THC and CH4 for NMHC) separately. For example, for 
NMHC measurements, perform drift validation on NMHC; do not validate 
THC and CH4 separately.
    (2) Drift validation requires two sets of emission calculations. 
For each set of calculations, include all the constituents in the drift 
validation. Calculate one set using the data before drift correction 
and calculate the other set after correcting all the data for drift 
according to Sec.  1065.672. Note that for purposes of drift 
validation, you must leave unaltered any negative emission results over 
a given test interval (i.e., do not set them to zero). These unaltered 
results are used when validating either test interval results or 
composite brake-specific emissions over the entire duty cycle for 
drift. For each constituent to be validated, both sets of calculations 
must include the following:
    (i) Calculated mass (or mass rate) emission values over each test 
interval.
    (ii) If you are validating each test interval based on brake-
specific values, calculate brake-specific emission values over each 
test interval.
    (iii) If you are validating over the entire duty cycle, calculate 
composite brake-specific emission values.
    (3) The duty cycle is validated for drift if you satisfy the 
following criteria:
    (i) For each regulated gaseous exhaust constituent, you must 
satisfy one of the following:
    (A) For each test interval of the duty cycle, the difference 
between the uncorrected and the corrected brake-specific emission 
values of the regulated constituent must be within  4% of 
the uncorrected value or the applicable emissions standard, whichever 
is

[[Page 57452]]

greater. Alternatively, the difference between the uncorrected and the 
corrected emission mass (or mass rate) values of the regulated 
constituent must be within  4% of the uncorrected value or 
the composite work (or power) multiplied by the applicable emissions 
standard, whichever is greater. For purposes of validating each test 
interval, you may use either the reference or actual composite work (or 
power).
    (B) For each test interval of the duty cycle and for each 
subcomponent of the regulated constituent, the difference between the 
uncorrected and the corrected brake-specific emission values must be 
within  4% of the uncorrected value. Alternatively, the 
difference between the uncorrected and the corrected emissions mass (or 
mass rate) values must be within  4% of the uncorrected 
value.
    (C) For the entire duty cycle, the difference between the 
uncorrected and the corrected composite brake-specific emission values 
of the regulated constituent must be within  4% of the 
uncorrected value or applicable emission standard, whichever is 
greater.
    (D) For the entire duty cycle and for each subcomponent of the 
regulated constituent, the difference between the uncorrected and the 
corrected composite brake-specific emission values must be within 
 4% of the uncorrected value.
    (ii) Where no emission standard applies for CO2, you 
must satisfy one of the following:
    (A) For each test interval of the duty cycle, the difference 
between the uncorrected and the corrected brake-specific CO2 
values must be within  4% of the uncorrected value; or the 
difference between the uncorrected and the corrected CO2 
mass (or mass rate) values must be within  4% of the 
uncorrected value.
    (B) For the entire duty cycle, the difference between the 
uncorrected and the corrected composite brake-specific CO2 
values must be within  4% of the uncorrected value.
    (4) If the test is not validated for drift as described in 
paragraph (b)(1) of this section, you may consider the test results for 
the duty cycle to be valid only if, using good engineering judgment, 
the observed drift does not affect your ability to demonstrate 
compliance with the applicable emission standards. For example, if the 
drift-corrected value is less than the standard by at least two times 
the absolute difference between the uncorrected and corrected values, 
you may consider the data to be valid for demonstrating compliance with 
the applicable standard.

Subpart G--[Amended]

0
74. Section 1065.602 is amended by revising paragraph (f)(3) 
introductory text, (h), and (l)(1) to read as follows:

Sec.  1065.602  Statistics.

* * * * *
    (f) * * *
    (3) Use Table 1 of this section to compare t to the 
tcrit values tabulated versus the number of degrees of 
freedom. If t is less than tcrit, then t passes the t-test. 
The Microsoft Excel software has a TINV function that returns 
equivalent results and may be used in place of Table 1, which follows:
* * * * *
    (h) Slope. Calculate a least-squares regression slope, 
a1y, as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.021

Example:

N = 6000
y1 = 2045.8
y = 1050.1
yref 1 = 2045.0
yref = 1055.3
[GRAPHIC] [TIFF OMITTED] TR15SE11.022

a1y = 1.0110
* * * * *
    (l) * * *
    (1) To estimate the flow-weighted mean raw exhaust NOX 
concentration from a turbocharged heavy-duty compression-ignition 
engine at a NOX standard of 2.5 g/(kW[middot]hr), you may do 
the following:
    (i) Based on your engine design, approximate a map of maximum 
torque versus speed and use it with the applicable normalized duty 
cycle in the standard-setting part to generate a reference duty cycle 
as described in Sec.  1065.610. Calculate the total reference work, 
Wref, as described in Sec.  1065.650. Divide the reference 
work by the duty cycle's time interval, [Delta]tdutycycle, 
to determine mean reference power, Pref.
    (ii) Based on your engine design, estimate maximum power, 
Pmax, the design speed at maximum power, fnmax, 
the design maximum intake manifold boost pressure, pinmax, 
and temperature, Tinmax. Also, estimate a mean fraction of 
power that is lost due to friction and pumping, Pfrict. Use 
this information along with the engine displacement volume, 
Vdisp, an approximate volumetric efficiency, 
[eta]V, and the number of engine strokes per power stroke 
(2-stroke or 4-stroke), Nstroke, to estimate the maximum raw 
exhaust molar flow rate, nehmax.
    (iii) Use your estimated values as described in the following 
example calculation:

[[Page 57453]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.023

Example:

eNOx = 2.5 g/(kW[middot]hr)
Wref = 11.883 kW[middot]hr
MNOx = 46.0055 g/mol = 46.0055[middot]10-\6\ 
g/[mu]mol
[Delta]tdutycycle = 20 min = 1200 s
Pref = 35.65 kW
Pfrict = 15%
Pmax = 125 kW
pmax = 300 kPa = 300,000 Pa
Vdisp = 3.0 l = 0.0030 m\3\/r
fnmax = 2,800 r/min = 46.67 r/s
Nstroke = 4
[eta]V = 0.9
R = 8.314472 J/(mol[middot]K)
Tmax = 348.15 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.024

nexhmax = 6.53 mol/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.025

xexp = 189.4 [micro]mol/mol
* * * * *

0
75. Section 1065.610 is amended by revising paragraphs (a), (b)(1), and 
(c) to read as follows:

Sec.  1065.610  Duty cycle generation.

* * * * *
    (a) Maximum test speed, fntest. This section generally 
applies to duty cycles for variable-speed engines. For constant-speed 
engines subject to duty cycles that specify normalized speed commands, 
use the no-load governed speed as the measured fntest. This 
is the highest engine speed where an engine outputs zero torque. For 
variable-speed engines, determine the measured fntest from 
the power-versus-speed map, generated according to Sec.  1065.510, as 
follows:
    (1) Based on the map, determine maximum power, Pmax, and 
the speed at which maximum power occurred, fnPmax. If 
maximum power occurs at multiple speeds, take fnPmax as the 
lowest of these speeds. Divide every recorded power by Pmax 
and divide every recorded speed by fnPmax. The result is a 
normalized power-versus-speed map. Your measured fntest is 
the speed at which the sum of the squares of normalized speed and power 
is maximum. Note that if multiple maximum values are found, 
fntest should be taken as the lowest speed of all points 
with the same maximum sum of squares. Determine fntest as 
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.026

Where:

    fntest = maximum test speed.
    i = an indexing variable that represents one recorded value of 
an engine map.
    fnnormi = an engine speed normalized by dividing it 
by fnPmax.
    Pnormi = an engine power normalized by dividing it by 
Pmax.

    Example:

(fnnorm1 = 1.002, Pnorm1 = 0.978, fn1 
= 2359.71)
(fnnorm2 = 1.004, Pnorm2 = 0.977, fn2 
= 2364.42)
(fnnorm3 = 1.006, Pnorm3 = 0.974, fn3 
= 2369.13)
(fnnorm1\2\ + Pnorm1\2\) = (1.002\2\ + 0.978\2\) 
= 1.960
(fnnorm2\2\ + Pnorm2\2\) = (1.004\2\ + 0.977\2\) 
= 1.963
(fnnorm3\2\ + Pnorm3\2\) = (1.006\2\ + 0.974\2\) 
= 1.961
maximum = 1.963 at-i = 2
    fntest = 2,364.42 r/min

[[Page 57454]]

    (2) For engines with a high-speed governor that will be subject to 
a reference duty cycle that specifies normalized speeds greater than 
100%, calculate an alternate maximum test speed, fntest,alt, 
as specified in this paragraph (a)(2). If fntest,alt is less 
than the measured maximum test speed, fntest, determined in 
paragraph (a)(1) of this section, replace fntest with 
fntest,alt. In this case, fntest,alt becomes the 
``maximum test speed'' for that engine. Note that Sec.  1065.510 allows 
you to apply an optional declared maximum test speed to the final 
measured maximum test speed determined as an outcome of the comparison 
between fntest, and fntest,alt in this paragraph 
(a)(2). Determine fntest,alt as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.027

Where:

fntest,alt = alternate maximum test speed
fnhi,idle = warm high-idle speed
fnidle = warm idle speed
% speedmax = maximum normalized speed from duty cycle

    Example:
fnhi,idle = 2,200 r/min
fnidle = 800 r/min
% speedmax = 105% (Nonroad CI Transient Cycle)
fntest,alt = (2,200-800)/105% + 800
fntest,alt = 2,133 r/min

    (3) For variable-speed engines, transform normalized speeds to 
reference speeds according to paragraph (c) of this section by using 
the measured maximum test speed determined according to paragraphs 
(a)(1) and (2) of this section--or use your declared maximum test 
speed, as allowed in Sec.  1065.510.
    (4) For constant-speed engines, transform normalized speeds to 
reference speeds according to paragraph (c) of this section by using 
the measured no-load governed speed--or use your declared maximum test 
speed, as allowed in Sec.  1065.510.
    (b) * * *
    (1) Based on the map, determine maximum power, Pmax, and 
the speed at which maximum power occurs, fnPmax. If maximum 
power occurs at multiple speeds, take fnPmax as the lowest 
of these speeds. Divide every recorded power by Pmax and 
divide every recorded speed by fnPmax. The result is a 
normalized power-versus-speed map. Your measured Ttest is 
the torque at which the sum of the squares of normalized speed and 
power is maximum. Note that that if multiple maximum values are found, 
Ttest should be taken as the highest torque of all points 
with the same maximum sum of squares. Determine Ttest as 
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.028

Where:

    Ttest = maximum test torque.

    Example:

(fnnorm1 = 1.002, Pnorm1 = 0.978, T1 = 
722.62 N[middot]m)
(fnnorm2 = 1.004, Pnorm2 = 0.977, T2 = 
720.44 N[middot]m)
(fnnorm3 = 1.006, Pnorm3 = 0.974, T3 = 
716.80 N[middot]m)
(fnnorm1\2\ + Pnorm1\2\) = (1.002\2\ + 0.978\2\) 
= 1.960
(fnnorm1\2\ + Pnorm1\2\) = (1.004\2\ + 0.977\2\) 
= 1.963
(fnnorm1\2\ + Pnorm1\2\) = (1.006\2\ + 0.974\2\) 
= 1.961
maximum = 1.963 at--i = 2
Ttest-- = 720.44 N[middot]m
* * * * *
    (c) Generating reference speed values from normalized duty cycle 
speeds. Transform normalized speed values to reference values as 
follows:
    (1) % speed. If your normalized duty cycle specifies % speed 
values, use your warm idle speed and your maximum test speed to 
transform the duty cycle, as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.029

    Example:

% speed = 85%
fntest = 2,364 r/min
fnidle = 650 r/min
fnref = 85% [middot] (2,364 - 650) + 650
fnref = 2,107 r/min

    (2) A, B, and C speeds. If your normalized duty cycle specifies 
speeds as A, B, or C values, use your power-versus-speed curve to 
determine the lowest speed below maximum power at which 50% of maximum 
power occurs. Denote this value as nlo. Take nlo 
to be warm idle speed if all power points at speeds below the maximum 
power speed are higher than 50% of maximum power. Also determine the 
highest speed above maximum power at which 70% of maximum power occurs. 
Denote this value as nhi. If all power points at speeds 
above the maximum power speed are higher than 70% of maximum power, 
take nhi to be the declared maximum safe engine speed or the 
declared maximum representative engine speed, whichever is lower. Use 
nhi and nlo to calculate reference values for A, 
B, or C speeds as follows:

[[Page 57455]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.030

    Example:

nlo = 1005 r/min
nhi = 2385 r/min
fnrefA = 0.25 [middot] (2385 - 1005) + 1005
fnrefB = 0.50 [middot] (2385 - 1005) + 1005
fnrefC = 0.75 [middot] (2385 - 1005) + 1005
fnrefA = 1350 r/min
fnrefB = 1695 r/min
fnrefC = 2040 r/min

    (3) Intermediate speed. If your normalized duty cycle specifies a 
speed as ``intermediate speed,'' use your torque-versus-speed curve to 
determine the speed at which maximum torque occurs. This is peak torque 
speed. If maximum torque occurs in a flat region of the torque-versus-
speed curve, your peak torque speed is the midpoint between the lowest 
and highest speeds at which the trace reaches the flat region. For 
purposes of this paragraph (c)(3), a flat region is one in which 
measured torque values are within 2% of the maximum recorded value. 
Identify your reference intermediate speed as one of the following 
values:
* * * * *

0
76. Section 1065.640 is amended by revising paragraphs (b)(1), (b)(2), 
(b)(5), (e)(3), (e)(4), and (e)(7) to read as follows:

Sec.  1065.640  Flow meter calibration calculations.

* * * * *
    (b) * * *
    (1) PDP volume pumped per revolution, Vrev (m\3\/r):
    [GRAPHIC] [TIFF OMITTED] TR15SE11.031
    
    Example:

n&ref = 25.096 mol/s
R = 8.314472 J/(mol [middot] K)
Tin = 299.5 K
Pin = 98290 Pa
fnPDP = 1205.1 r/min = 20.085 r/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.032

Vrev = 0.03166 m\3\/r
    (2) PDP slip correction factor, Ks (s/r):
    [GRAPHIC] [TIFF OMITTED] TR15SE11.033
    
    Example:

fnPDP = 1205.1 r/min = 20.085 r/s
Pout = 100.103 kPa
Pin = 98.290 kPa
[GRAPHIC] [TIFF OMITTED] TR15SE11.034

Ks = 0.006700 s/r
* * * * *
    (5) The following example illustrates these calculations:

       Table 1 of Sec.   1065.640--Example of PDP Calibration Data
------------------------------------------------------------------------
                                                    a1 (m\3\/  a0 (m\3\/
                  f8nPDP (r/min)                       min)        r)
------------------------------------------------------------------------
755.0.............................................      50.43      0.056
987.6.............................................      49.86     -0.013
1254.5............................................      48.54      0.028
1401.3............................................      47.30     -0.061
------------------------------------------------------------------------

* * * * *
    (e) * * *
    (3) If the standard deviation of all the Cd values is 
less than or equal to 0.3% of the mean Cd, use the mean 
Cd in Eq 1065.642-6, and use the CFV only up to the highest 
r measured during calibration using the following equation:

[[Page 57456]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.035

Where:

    [Delta]p--CFV = Differential static pressure; venturi 
inlet minus venturi outlet.

    (4) If the standard deviation of all the Cd values 
exceeds 0.3% of the mean Cd, omit the Cd values 
corresponding to the data point collected at the highest r measured 
during calibration.
* * * * *
    (7) If the standard deviation of the remaining Cd values 
is less than or equal to 0.3% of the mean of the remaining 
Cd, use that mean Cd in Eq 1065.642-6, and use 
the CFV values only up to the highest r associated with the remaining 
Cd.
* * * * *

0
77. Section 1065.642 is amended by revising paragraph (a) to read as 
follows:

Sec.  1065.642  SSV, CFV, and PDP molar flow rate calculations.

* * * * *
    (a) PDP molar flow rate. Based upon the speed at which you operate 
the PDP for a test interval, select the corresponding slope, 
a1, and intercept, a0, as calculated in Sec.  
1065.640, to calculate molar flow rate, n as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.036

Where:

[GRAPHIC] [TIFF OMITTED] TR15SE11.037

    Example:

a1 = 50.43 (m\3\/min) = 0.8405 (m\3\/s)
fnPDP = 755.0 r/min = 12.58 r/s
pout = 99950 Pa
pin = 98575 Pa
a0 = 0.056 (m\3\/r)
R = 8.314472 J/(mol[middot]K)
Tin = 323.5 K
Cp = 1000 (J/m\3\)/kPa
Ct = 60 s/min
[GRAPHIC] [TIFF OMITTED] TR15SE11.038

Vrev = 0.06383 m\3\/r
[GRAPHIC] [TIFF OMITTED] TR15SE11.039

n = 29.428 mol/s
* * * * *

0
78. Section 1065.645 is amended by revising the introductory text and 
paragraph (a) to read as follows:

Sec.  1065.645  Amount of water in an ideal gas.

    This section describes how to determine the amount of water in an 
ideal gas, which you need for various performance verifications and 
emission calculations. Use the equation for the vapor pressure of water 
in paragraph (a) of this section or another appropriate equation and, 
depending on whether you measure dewpoint or relative humidity, perform 
one of the calculations in paragraph (b) or (c) of this section. The 
equations for the vapor pressure of water as presented in this section 
are derived from equations in ``Saturation Pressure of Water on the New 
Kelvin Temperature Scale'' (Goff, J.A., Transactions American Society 
of Heating and Air-Conditioning Engineers, Vol. 63, No. 1607, pages 
347-354). Note that the equations were originally published to derive 
vapor pressure in units of atmospheres and have been modified to derive 
results in units of kPa by converting the last term in each equation.
    (a) Vapor pressure of water. Calculate the vapor pressure of water 
for a given saturation temperature condition, Tsat, as 
follows, or use good engineering judgment to use a different 
relationship of the vapor pressure of water to a given saturation 
temperature condition:
(1) For humidity measurements made at ambient temperatures from (0 to 
100) [deg]C, or for humidity measurements made over super-cooled water 
at ambient temperatures from (-50 to 0) [deg]C, use the following 
equation:

[[Page 57457]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.040

Where:

pH20 = vapor pressure of water at saturation temperature 
condition, kPa.
Tsat = saturation temperature of water at measured 
conditions, K.
    Example:

Tsat = 9.5 [deg]C
Tsat = 9.5 + 273.15 = 282.65 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.041

log10(pH20) = 0.074297
pH20 = 10\0.074297\ = 1.186581 kPa

    (2) For humidity measurements over ice at ambient temperatures from 
(-100 to 0) [deg]C, use the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.042

    Example:

Tice = -15.4 [deg]C
Tice = -15.4 + 273.15 = 257.75 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.043

log10(pH20) = -0.798207
pH20 = 10 -0.79821 = 0.159145 kPa
* * * * *

0
79. Section 1065.650 is amended as follows:
0
a. By revising paragraphs (c) introductory text, (c)(1), and (c)(4).
0
b. By adding paragraph (c)(5).
0
c. By revising paragraphs (d)(7), (e)(4), and (f)(4).

Sec.  1065.650  Emission calculations.

* * * * *
    (c) Total mass of emissions over a test interval. To calculate the 
total mass of an emission, multiply a concentration by its respective 
flow. For all systems, make preliminary calculations as described in 
paragraph (c)(1) of this section to correct concentrations. Next, use 
the method in paragraphs (c)(2) through (4) of this section that is 
appropriate for your system. Finally, if necessary, calculate the mass 
of NMHC as described in paragraph (c)(5) of this section for all 
systems. Calculate the total mass of emissions as follows:
    (1) Concentration corrections. Perform the following sequence of 
preliminary calculations on recorded concentrations:
    (i) Correct all gaseous emission analyzer concentration readings, 
including continuous readings, sample bag readings, and dilution air 
background readings, for drift as described in Sec.  1065.672. Note 
that you must omit this step where brake-specific emissions are 
calculated without the drift correction for performing the drift 
validation according to Sec.  1065.550(b). When applying the initial 
THC and CH4 contamination readings according to Sec.  
1065.520(g), use the same values for both sets of calculations. You may 
also use as-measured values in the initial set of calculations and 
corrected values in the drift-corrected set of calculations as 
described in Sec.  1065.520(g)(7).

[[Page 57458]]

    (ii) Correct all THC and CH4 concentrations, including 
continuous readings, sample bags readings, and dilution air background 
readings, for initial contamination, as described in Sec.  1065.660(a).
    (iii) Correct all concentrations measured on a ``dry'' basis to a 
``wet'' basis, including dilution air background concentrations, as 
described in Sec.  1065.659.
    (iv) Calculate all NMHC and CH4 concentrations, 
including dilution air background concentrations, as described in Sec.  
1065.660.
    (v) For emission testing with an oxygenated fuel, calculate any HC 
concentrations, including dilution air background concentrations, as 
described in Sec.  1065.665. See subpart I of this part for testing 
with oxygenated fuels.
    (vi) Correct all the NOX concentrations, including 
dilution air background concentrations, for intake-air humidity as 
described in Sec.  1065.670.
* * * * *
    (4) Additional provisions for diluted exhaust sampling; continuous 
or batch. The following additional provisions apply for sampling 
emissions from diluted exhaust:
    (i) For sampling with a constant dilution ratio, DR, of diluted 
exhaust versus exhaust flow (e.g., secondary dilution for PM sampling), 
calculate m using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.044

    Example:

mPMdil = 6.853 g
DR = 6:1
mPM = 6.853 [middot] 6
mPM = 41.118 g
    (ii) For continuous or batch sampling, you may measure background 
emissions in the dilution air. You may then subtract the measured 
background emissions, as described in Sec.  1065.667.
    (5) Mass of NMHC. Compare the corrected mass of NMHC to corrected 
mass of THC. If the corrected mass of NMHC is greater than 0.98 times 
the corrected mass of THC, take the corrected mass of NMHC to be 0.98 
times the corrected mass of THC. If you omit the NMHC calculations as 
described in Sec.  1065.660(b)(1), take the corrected mass of NMHC to 
be 0.98 times the corrected mass of THC.
    (d) * * *
    (7) Integrate the resulting values for power over the test 
interval. Calculate total work as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.045

Where:

W = total work from the primary output shaft.
Pi = instantaneous power from the primary output shaft 
over an interval i.
[GRAPHIC] [TIFF OMITTED] TR15SE11.046

    Example:

N = 9000
[fnof]n1 = 1800.2 r/min
[fnof]n2 = 1805.8 r/min
T1 = 177.23 N[middot]m
T2 = 175.00 N[middot]m
Crev = 2[middot][pi] rad/r
Ct1 = 60 s/min
Cp = 1000 (N[middot]m[middot]rad/s)/kW
[fnof]record = 5 Hz
Ct2 = 3600 s/hr
[GRAPHIC] [TIFF OMITTED] TR15SE11.047

P1 = 33.41 kW
P2 = 33.09 kW
Using Eq. 1065.650-5,
[Delta]t = 1/5 = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.048

    W = 16.875 kW [middot] hr
* * * * *
    (e) * * *
    (4) The following example shows how to calculate mass of emissions 
using mean mass rate and mean power:
MCO = 28.0101 g/mol
xCO = 12.00 mmol/mol = 0.01200 mol/mol
n = 1.530 mol/s
fn = 3584.5 r/min = 375.37 rad/s
T = 121.50 N [middot] m
m = 28.0101 [middot] 0.01200 [middot] 1.530
m = 0.514 g/s = 1850.4 g/hr
P = 121.5[middot]375.37
P = 45607 W
P = 45.607 kW
eCO = 1850.4/45.61
eCO = 40.57 g/(kW[middot]hr)

    (f) * * *
    (4) Example. The following example shows how to calculate mass of 
emissions using proportional values:

N = 3000
[fnof]record = 5 Hz
efuel = 285 g/(kW[middot]hr)
wfuel = 0.869 g/g
Mc = 12.0107 g/mol
n1 = 3.922 mol/s = 14119.2 mol/hr
xCcombdry1 = 91.634 mmol/mol = 0.091634 mol/mol
xH2Oexh1 = 27.21 mmol/mol = 0.02721 mol/mol
Using Eq. 1065.650-5,
[Delta]t = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.049

W = 5.09 (kW[middot]hr)
* * * * *

0
80. Section 1065.655 is amended by revising paragraphs (b), (c)(5), 
(d), and (e)(3) and adding paragraph (f) to read as follows:

Sec.  1065.655  Chemical balances of fuel, intake air, and exhaust.

* * * * *
    (b) Procedures that require chemical balances. We require chemical 
balances when you determine the following:
    (1) A value proportional to total work, W when you choose to 
determine brake-specific emissions as described in Sec.  1065.650(f).
    (2) The amount of water in a raw or diluted exhaust flow, 
xH2Oexh, when you do not measure the amount of water to 
correct for the amount of water removed by a sampling system. Correct 
for removed water according to Sec.  1065.659.
    (3) The calculated dilution air flow when you do not measure 
dilution air flow to correct for background emissions as described in 
Sec.  1065.667(c) and (d).
    (c) * * *
    (5) The following example is a solution for xdil/exh,x, 
xH2Oexh, and xCcombdry using the equations in 
paragraph (c)(4) of this section:

[[Page 57459]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.050

[GRAPHIC] [TIFF OMITTED] TR15SE11.051

[[Page 57460]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.052

[alpha] = 1.8
[beta] = 0.05
[gamma] = 0.0003
[delta] = 0.0001
    (d) Carbon mass fraction. Determine carbon mass fraction of fuel, 
wc, using one of the following methods:
    (1) You may calculate wc as described in this paragraph 
(d)(1) based on measured fuel properties. To do so, you must determine 
values for [alpha] and [beta] in all cases, but you may set [gamma] and 
[delta] to zero if the default value listed in Table 1 of this section 
is zero. Calculate wc using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.053

Where:

wc = carbon mass fraction of fuel.
MC = molar mass of carbon.
[alpha] = atomic hydrogen-to-carbon ratio of the mixture of fuel(s) 
being combusted, weighted by molar consumption.
MH = molar mass of hydrogen.

[[Page 57461]]

[beta] = atomic oxygen-to-carbon ratio of the mixture of fuel(s) 
being combusted, weighted by molar consumption.
MO = molar mass of oxygen.
[gamma] = atomic sulfur-to-carbon ratio of the mixture of fuel(s) 
being combusted, weighted by molar consumption.
MS = molar mass of sulfur.
[delta] = atomic nitrogen-to-carbon ratio of the mixture of fuel(s) 
being combusted, weighted by molar consumption.
MN = molar mass of nitrogen.

    Example:

[alpha] = 1.8
[beta] = 0.05
[gamma] = 0.0003
[delta] = 0.0001
MC = 12.0107
MH = 1.01
MO = 15.9994
MS = 32.065
MN = 14.0067
[GRAPHIC] [TIFF OMITTED] TR15SE11.054

wc = 0.8205

    (2) You may use the default values in the following table to 
determine wc for a given fuel:

   Table 1 of Sec.   1065.655--Default Values of [alpha], [beta], [gamma], [delta], and wc, for Various Fuels
----------------------------------------------------------------------------------------------------------------
                                                                                                     Carbon mass
                      Fuel                        Atomic hydrogen, oxygen, sulfur, and nitrogen-to-   fraction,
                                                   carbon ratios  CH[alpha]O[beta]S[gamma]N[delta]      wc g/g
----------------------------------------------------------------------------------------------------------------
Gasoline.......................................  CH1.85O0S0N0                                              0.866
E10 Gasoline...................................  CH1.92O0.03S0N0                                           0.833
E15 Gasoline...................................  CH1.95O0.05S0N0                                           0.817
E85 Gasoline...................................  CH2.73O0.38S0N0                                           0.576
1 Diesel..............................  CH1.93O0S0N0                                              0.861
2 Diesel..............................  CH1.80O0S0N0                                              0.869
Liquefied Petroleum Gas........................  CH2.64O0S0N0                                              0.819
Natural gas....................................  CH3.78 O0.016S0N0                                         0.747
E100 Ethanol...................................  CH3O0.5S0N0                                               0.521
M100 Methanol..................................  CH4O1S0N0                                                 0.375
----------------------------------------------------------------------------------------------------------------
Residual fuel blends...........................   Must be determined by measured fuel properties as described in
                                                                 paragraph (d)(1) of this section.
----------------------------------------------------------------------------------------------------------------

    (e) * * *
    (3) Fuel mass flow rate calculation. Based on mfuel, 
calculate nexh as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.055

Where:

nexh = raw exhaust molar flow rate from which you 
measured emissions.
mfuel = fuel flow rate including humidity in intake air.

    Example:

mfuel = 7.559 g/s
wc = 0.869 g/g
MC = 12.0107 g/mol
xCcombdry = 99.87 mmol/mol = 0.09987 mol/mol
xH20exhdry = 107.64 mmol/mol = 0.10764 mol/mol
[GRAPHIC] [TIFF OMITTED] TR15SE11.056

nexh = 6.066 mol/s

    (f) Calculated raw exhaust molar flow rate from measured intake air 
molar flow rate, dilute exhaust molar flow rate, and dilute chemical 
balance. You may calculate the raw exhaust molar flow rate, 
nexh, based on the measured intake air molar flow rate, 
nint, the measured dilute exhaust molar flow rate, 
ndexh, and the values calculated using the chemical balance 
in paragraph (c) of this section. Note that the chemical balance must 
be based on dilute exhaust gas concentrations. For continuous-flow 
calculations, solve for the chemical balance in paragraph (c) of this 
section at the same frequency that you update and record 
nint and ndexh. This calculated nexh 
may be used for the PM dilution ratio verification in Sec.  1065.546; 
the calculation of dilution air molar flow rate in the background 
correction in Sec.  1065.667; and the calculation of mass of emissions 
in Sec.  1065.650(c) for species that are measured in the raw exhaust.
    (1) Crankcase flow rate. If engines are not subject to crankcase 
controls under the standard-setting part, calculate raw exhaust flow as 
described in paragraph (e)(1) of this section.
    (2) Dilute exhaust and intake air molar flow rate calculation. 
Calculate nexh as follows:

[[Page 57462]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.057

    Example:

nint = 7.930mol/s
xraw/exhdry = 0.1544 mol/mol
xint/exhdry = 0.1451 mol/mol
xH2Oexh = 32.46 mmol/mol - 0.03246 mol/mol
ndexh = 49.02 mol/s
nexh = (0.1544-0.145( [middot] (1-0.03246) [middot] 49.02 + 
7.930 = 0.4411 + 7.930 = 8.371 mol/s

0
81. Section 1065.659 is amended by revising paragraphs (a), (b), and 
(c) to read as follows:

Sec.  1065.659  Removed water correction.

    (a) If you remove water upstream of a concentration measurement, x, 
or upstream of a flow measurement, n, correct for the removed water. 
Perform this correction based on the amount of water at the 
concentration measurement, xH2O[emission]meas, and at the 
flow meter, xH2Oexh, whose flow is used to determine the 
mass emission rate or total mass over a test interval. For continuous 
analyzers downstream of a sample dryer for transient and ramped-modal 
cycles, you must apply this correction on a continuous basis over the 
test interval, even if you use one of the options in Sec.  
1065.145(e)(2) that results in a constant value for 
xH2O[emission]meas because xH2Oexh varies over 
the test interval. For batch analyzers, determine the flow-weighted 
average based on the continuous xH2Oexh values determined as 
described in paragraph (c) of this section. For batch analyzers, you 
may determine the flow-weighted average xH2Oexh based on a 
single value of xH2Oexh determined as described in 
paragraphs (c)(2) and (3) of this section, using flow-weighted average 
or batch concentration inputs.
    (b) Determine the amount of water remaining downstream of a sample 
dryer and at the concentration measurement using one of the methods 
described in Sec.  1065.145(e)(2). If you use a sample dryer upstream 
of an analyzer and if the calculated amount of water remaining 
downstream of the sample dryer and at the concentration measurement, 
xH2O[emission]meas, is higher than the amount of water at 
the flow meter, xH2Oexh, set xH2O[emission]meas 
equal to xH2Oexh. If you use a sample dryer upstream of 
storage media, you must be able to demonstrate that the sample dryer is 
removing water continuously (i.e., xH2Oexh is higher than 
xH2O[emission]meas throughout the test interval).
    (c) For a concentration measurement where you did not remove water, 
you may set xH2O[emission]meas equal to xH2Oexh. 
You may determine the amount of water at the flow meter, 
xH2Oexh, using any of the following methods:
    (1) Measure the dewpoint and absolute pressure and calculate the 
amount of water as described in Sec.  1065.645.
    (2) If the measurement comes from raw exhaust, you may determine 
the amount of water based on intake-air humidity, plus a chemical 
balance of fuel, intake air, and exhaust as described in Sec.  
1065.655.
    (3) If the measurement comes from diluted exhaust, you may 
determine the amount of water based on intake-air humidity, dilution 
air humidity, and a chemical balance of fuel, intake air, and exhaust 
as described in Sec.  1065.655.
* * * * *

0
82. Section 1065.660 is revised to read as follows:

Sec.  1065.660  THC, NMHC, and CH4 determination.

    (a) THC determination and initial THC/CH4 contamination 
corrections. (1) If we require you to determine THC emissions, 
calculate xTHC[THC-FID]cor using the initial THC 
contamination concentration xTHC[THC-FID]init from Sec.  
1065.520 as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.058

    Example:

xTHCuncor = 150.3 [mu]mol/mol
xTHCinit = 1.1 [mu]mol/mol
xTHCcor = 150.3--1.1
xTHCcor = 149.2 [mu]mol/mol

    (2) For the NMHC determination described in paragraph (b) of this 
section, correct xTHC[THC-FID] for initial THC contamination 
using Equation 1065.660-1. You may correct xTHC[NMC-FID] for 
initial contamination of the CH4 sample train using Equation 
1065.660-1, substituting in CH4 concentrations for THC.
    (3) For the CH4 determination described in paragraph (c) 
of this section, you may correct xTHC[NMC-FID] for initial 
THC contamination of the CH4 sample train using Equation 
1065.660-1, substituting in CH4 concentrations for THC.
    (b) NMHC determination. Use one of the following to determine NMHC 
concentration, xNMHC:
    (1) If you do not measure CH4, you may omit the 
calculation of NMHC concentrations and calculate the mass of NMHC as 
described in Sec.  1065.650(c)(5).
    (2) For nonmethane cutters, calculate xNMHC using the 
nonmethane cutter's penetration fraction (PF) of CH4 and the 
response factor penetration fraction (RFPF) of 
C2H6 from Sec.  1065.365, the response factor 
(RF) of the THC FID to CH4 from Sec.  1065.360, the initial 
THC contamination and dry-to-wet corrected THC concentration 
xTHC[THC-FID]cor as determined in paragraph (a) of this 
section, and the dry-to-wet corrected CH4 concentration 
xTHC[NMC-FID]cor optionally corrected for initial THC 
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined 
using an NMC configuration as outlined in Sec.  1065.365(d):

[[Page 57463]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.059

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the NMC FID during sampling through the NMC.
RFCH4[THC-FID] = response factor of THC FID to 
CH4, according to Sec.  1065.360(d).
RFPFC2H6[NMC-FID] = nonmethane cutter combined ethane 
response factor and penetration fraction, according to Sec.  
1065.365(d).

    Example:

xTHC[THC-FID]cor = 150.3 [micro]mol/mol
xTHC[NMC-FID]cor = 20.5 [micro]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.060

xNMHC = 131.4 [mu]mol/mol

    (ii) For penetration fractions determined using an NMC 
configuration as outlined in section Sec.  1065.365(e), use the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.061

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4 
penetration fraction, according to Sec.  1065.365(e).
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the THC FID during sampling through the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration 
fraction, according to Sec.  1065.365(e).

    Example:

xTHC[THC-FID]cor = 150.3 [mu]mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [mu]mol/mol
PFC2H6[NMC-FID] = 0.020
[GRAPHIC] [TIFF OMITTED] TR15SE11.062

xNMHC = 132.3 [mu]mol/mol

    (iii) For penetration fractions determined using an NMC 
configuration as outlined in section Sec.  1065.365(f), use the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.063

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4 
penetration fraction, according to Sec.  1065.365(f).
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the THC FID during sampling through the NMC.
RFPFC2H6[NMC-FID] = nonmethane cutter CH4 
combined ethane response factor and penetration fraction, according 
to Sec.  1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to 
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[THC-FID]cor = 150.3 [micro]mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [micro]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 0.980
[GRAPHIC] [TIFF OMITTED] TR15SE11.067

xNMHC = 132.5 [mu]mol/mol

    (3) For a GC-FID, calculate xNMHC using the THC 
analyzer's response factor (RF) for CH4, from Sec.  
1065.360, and the initial THC contamination and dry-to-wet corrected 
THC concentration xTHC[THC-FID]cor as determined in 
paragraph (a) of this section as follows:

[[Page 57464]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.068

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID.
xCH4= concentration of CH4, dry-to-wet 
corrected, as measured by the GC-FID.
RFCH4[THC-FID] = response factor of THC-FID to 
CH4.

    Example:

xTHC[THC-FID[cor = 145.6 [mu]mol/mol
RFCH4[THC-FID] = 0.970
xCH4 = 18.9 [mu]mol/mol
xNMHC = 145.6-0.970 [middot] 18.9
xNMHC = 127.3 [mu]mol/mol

    (c) CH4 determination. Use one of the following methods 
to determine CH4 concentration, xCH4:
    (1) For nonmethane cutters, calculate xCH4 using the 
nonmethane cutter's penetration fraction (PF) of CH4 and the 
response factor penetration fraction (RFPF) of 
C2H6 from Sec.  1065.365, the response factor 
(RF) of the THC FID to CH4 from Sec.  1065.360, the initial 
THC contamination and dry-to-wet corrected THC concentration 
xTHC[THC-FID]cor as determined in paragraph (a) of this 
section, and the dry-to-wet corrected CH4 concentration 
xTHC[NMC-FID]cor optionally corrected for initial THC 
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined 
using an NMC configuration as outlined in Sec.  1065.365(d):
[GRAPHIC] [TIFF OMITTED] TR15SE11.069

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor 
and penetration fraction of the nonmethane cutter, according to 
Sec.  1065.365(d).
RFCH4[THC-FID] = response factor of THC FID to 
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.070

xCH4 = 7.69 [mu]mol/mol

    (ii) For penetration fractions determined using an NMC 
configuration as outlined in Sec.  1065.365(e), use the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.071

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration 
fraction, according to Sec.  1065.365(e).
RFCH4[THC-FID] = response factor of THC FID to 
CH4, according to Sec.  1065.360(d).
PFCH4[NMC-FID] = nonmethane cutter CH4 
penetration fraction, according to Sec.  1065.365(e).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
PFC2H6[NMC-FID] = 0.020
RFCH4[THC-FID] = 1.05
PFCH4[NMC-FID] = 0.990
[GRAPHIC] [TIFF OMITTED] TR15SE11.072

xCH4 = 7.25 [mu]mol/mol

    (iii) For penetration fractions determined using an NMC 
configuration as outlined in Sec.  1065.365(f), use the following 
equation:

[[Page 57465]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.073

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
contamination (optional) and dry-to-wet corrected, as measured by 
the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
contamination and dry-to-wet corrected, as measured by the THC FID 
during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor 
and penetration fraction of the nonmethane cutter, according to 
Sec.  1065.365(f).
PFCH4[NMC-FID] = nonmethane cutter CH4 
penetration fraction, according to Sec.  1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to 
CH4, according to Sec.  1065.360(d).

    Example:

xTHC[NMC-FID]cor = 10.4 [mu]mol/mol
xTHC[THC-FID]cor = 150.3 [mu]mol/mol
RFPFC2H6[NMC-FID] = 0.019
PFCH4[NMC-FID] = 0.990
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.074

xCH4 = 7.78 [mu]mol/mol

    (2) For a GC-FID, xCH4 is the actual dry-to-wet 
corrected CH4 concentration as measured by the analyzer.

0
83. Section 1065.667 is revised to read as follows:

Sec.  1065.667  Dilution air background emission correction.

    (a) To determine the mass of background emissions to subtract from 
a diluted exhaust sample, first determine the total flow of dilution 
air, ndil, over the test interval. This may be a measured 
quantity or a calculated quantity. Multiply the total flow of dilution 
air by the mean mole fraction (i.e., concentration) of a background 
emission. This may be a time-weighted mean or a flow-weighted mean 
(e.g., a proportionally sampled background). Finally, multiply by the 
molar mass, M, of the associated gaseous emission constituent. The 
product of ndil and the mean molar concentration of a 
background emission and its molar mass, M, is the total background 
emission mass, m. In the case of PM, where the mean PM concentration is 
already in units of mass per mole of sample, MPM, multiply 
it by the total amount of dilution air flow, and the result is the 
total background mass of PM, mPM. Subtract total background 
mass from total mass to correct for background emissions.
    (b) You may determine the total flow of dilution air by a direct 
flow measurement.
    (c) You may determine the total flow of dilution air by subtracting 
the calculated raw exhaust molar flow as described in Sec.  1065.655(f) 
from the measured dilute exhaust flow. This may be done by totaling 
continuous calculations or by using batch results.
    (d) You may determine the total flow of dilution air from the 
measured dilute exhaust flow and a chemical balance of the fuel, intake 
air, and dilute exhaust as described in Sec.  1065.655. For this 
option, the molar flow of dilution air is calculated by multiplying the 
dilute exhaust flow by the mole fraction of dilution gas to dilute 
exhaust, xdil[sol]exh, from the dilute chemical balance. 
This may be done by totaling continuous calculations or by using batch 
results. For example, to use batch results, the total flow of dilution 
air is calculated by multiplying the total flow of diluted exhaust, 
ndexh, by the flow-weighted mean mole fraction of dilution 
air in diluted exhaust, xdil[sol]exh. Calculate 
xdil[sol]exh using flow-weighted mean concentrations of 
emissions in the chemical balance, as described in Sec.  1065.655. The 
chemical balance in Sec.  1065.655 assumes that your engine operates 
stoichiometrically, even if it is a lean-burn engine, such as a 
compression-ignition engine. Note that for lean-burn engines this 
assumption could result in an error in emission calculations. This 
error could occur because the chemical balance in Sec.  1065.655 treats 
excess air passing through a lean-burn engine as if it was dilution 
air. If an emission concentration expected at the standard is about 100 
times its dilution air background concentration, this error is 
negligible. However, if an emission concentration expected at the 
standard is similar to its background concentration, this error could 
be significant. If this error might affect your ability to show that 
your engines comply with applicable standards, we recommend that you 
either determine the total flow of dilution air using one of the more 
accurate methods in paragraph (b) or (c) of this section, or remove 
background emissions from dilution air by HEPA filtration, chemical 
adsorption, or catalytic scrubbing. You might also consider using a 
partial-flow dilution technique such as a bag mini-diluter, which uses 
purified air as the dilution air.
    (e) The following is an example of using the flow-weighted mean 
fraction of dilution air in diluted exhaust, xdil[sol]exh, 
and the total mass of background emissions calculated using the total 
flow of diluted exhaust, ndexh, as described in Sec.  
1065.650(c):
[GRAPHIC] [TIFF OMITTED] TR15SE11.075

    Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro]mol/mol = 0.05[sdot]10-6 
mol/mol
ndexh = 23280.5 mol
xdil[sol]exh = 0.843 mol/mol
mbkgndNOxdexh = 
46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g

    (f) The following is an example of using the fraction of dilution 
air in diluted exhaust, xdil/exh, and the mass rate of 
background emissions calculated using the flow rate of diluted exhaust, 
ndexh, as described in Sec.  1065.650(c):
[GRAPHIC] [TIFF OMITTED] TR15SE11.076

    Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro]mol/mol = 0.05[sdot]10-\6\ 
mol/mol

[[Page 57466]]

ndexh = 23280.5 mol/s
xdil/exh = 0.843 mol/mol
mbkgndNOxdexh = 
46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g/hr
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g/hr

0
84. Section 1065.670 is amended by revising the introductory text to 
read as follows:

Sec.  1065.670  NOX intake-air humidity and temperature 
corrections.

    See the standard-setting part to determine if you may correct 
NOX emissions for the effects of intake-air humidity or 
temperature. Use the NOX intake-air humidity and temperature 
corrections specified in the standard-setting part instead of the 
NOX intake-air humidity correction specified in this part 
1065. If the standard-setting part does not prohibit correcting 
NOX emissions for intake-air humidity according to this part 
1065, correct NOX concentrations for intake-air humidity as 
described in this section. See Sec.  1065.650(c)(1) for the proper 
sequence for applying the NOX intake-air humidity and 
temperature corrections. You may use a time-weighted mean combustion 
air humidity to calculate this correction if your combustion air 
humidity remains within a tolerance of 0.0025 mol/mol of 
the mean value over the test interval. For intake-air humidity 
correction, use one of the following approaches:
* * * * *

0
85. Section 1065.675 is amended by revising paragraph (d) to read as 
follows:

Sec.  1065.675  CLD quench verification calculations.

* * * * *
    (d) Calculate quench as follows:
    [GRAPHIC] [TIFF OMITTED] TR15SE11.077
    
Where:

quench = amount of CLD quench.
xNOdry = concentration of NO upstream of a bubbler, 
according to Sec.  1065.370(e)(4).
xNOwet = measured concentration of NO downstream of a 
bubbler, according to Sec.  1065.370(e)(9).
xH2Oexp = maximum expected mole fraction of water during 
emission testing, according to paragraph (b) of this section.
xH2Omeas = measured mole fraction of water during the 
quench verification, according to Sec.  1065.370(e)(7).
xNOmeas = measured concentration of NO when NO span gas 
is blended with CO2 span gas, according to Sec.  
1065.370(d)(10).
xNOact = actual concentration of NO when NO span gas is 
blended with CO2 span gas, according to Sec.  
1065.370(d)(11) and calculated according to Equation 1065.675-2.
xCO2exp = maximum expected concentration of 
CO2 during emission testing, according to paragraph (c) 
of this section.
xCO2act = actual concentration of CO2 when NO 
span gas is blended with CO2 span gas, according to Sec.  
1065.370(d)(9).
[GRAPHIC] [TIFF OMITTED] TR15SE11.078

Where:

xNOspan = the NO span gas concentration input to the gas 
divider, according to Sec.  1065.370(d)(5).
xCO2span = the CO2 span gas concentration 
input to the gas divider, according to Sec.  1065.370(d)(4).

    Example:

xNOdry = 1800.0 [micro]mol/mol
xNOwet = 1739.6 [micro]mol/mol
xH2Oexp = 0.030 mol/mol
xH2Omeas = 0.030 mol/mol
xNOmeas = 1515.2 [micro]mol/mol
xNOspan = 3001.6 [micro]mol/mol
xCO2exp = 3.2%
xCO2span = 6.1%
xCO2act = 2.98%
[GRAPHIC] [TIFF OMITTED] TR15SE11.079

[[Page 57467]]

quench = (-0.0036655-0. 014020171)[sdot]100% = -1.7685671%

Subpart H--[Amended]

0
86. Section 1065.750 is amended by revising paragraphs (a)(3) 
introductory text and (a)(4) to read as follows:

Sec.  1065.750  Analytical gases.

* * * * *
    (a) * * *
    (3) Use the following gas mixtures, with gases traceable within 
1% of the NIST-accepted value or other gas standards we 
approve:
* * * * *
    (4) You may use gases for species other than those listed in 
paragraph (a)(3) of this section (such as methanol in air, which you 
may use to determine response factors), as long as they are traceable 
to within 3% of the NIST-accepted value or other similar 
standards we approve, and meet the stability requirements of paragraph 
(b) of this section.
* * * * *

0
87. Section 1065.790 is amended by revising paragraph (a) to read as 
follows:

Sec.  1065.790  Mass standards.

    (a) PM balance calibration weights. Use PM balance calibration 
weights that are certified as NIST-traceable within 0.1% uncertainty. 
Calibration weights may be certified by any calibration lab that 
maintains NIST-traceability. Make sure your highest calibration weight 
has no greater than ten times the mass of an unused PM-sample medium.
* * * * *

Subpart J--[Amended]

0
88. Section 1065.915 is amended by revising Table 1 in paragraph (a) to 
read as follows:

Sec.  1065.915  PEMS instruments.

    (a) * * *

                                 Table 1 of Sec.   1065.915--Recommended Minimum PEMS Measurement Instrument Performance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Rise time, t10	90,
           Measurement             Measured quantity    and fall time,     Recording update      Accuracy \1\      Repeatability \1\       Noise \1\
                                        symbol              t90	10             frequency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Engine speed transducer.........  fn................  1 s...............  1 Hz means........  5% of pt. or 1% of  2% of pt. or 1% of  0.5% of max.
                                                                                               max.                max.
Engine torque estimator, BSFC     T or BSFC.........  1 s...............  1 Hz means........  8% of pt. or 5% of  2% of pt. or 1% of  1% of max.
 (This is a signal from an                                                                     max.                max.
 engine's ECM)
General pressure transducer (not  p.................  5 s...............  1 Hz..............  5% of pt. or 5% of  2% of pt. or 0.5%   1% of max.
 a part of another instrument)                                                                 max.                of max.
Atmospheric pressure meter        patmos............  50 s..............  0.1 Hz............  250 Pa............  200 Pa............  100 Pa.
General temperature sensor (not   T.................  5 s...............  1 Hz..............  1% of pt. K or 5 K  0.5% of pt. K or 2  0.5% of max 0.5 K.
 a part of another instrument)                                                                                     K.
General dewpoint sensor.........  Tdew..............  50 s..............  0.1 Hz............  3 K...............  1 K...............  1 K.
Exhaust flow meter..............  n.................  1 s...............  1 Hz means........  5% of pt. or 3% of  2% of pt..........  2% of max.
                                                                                               max.
Dilution air, inlet air,          n.................  1 s...............  1 Hz means........  2.5% of pt. or      1.25% of pt. or     1% of max.
 exhaust, and sample flow meters                                                               1.5% of max.        0.75% of max.
Continuous gas analyzer.........  x.................  5 s...............  1 Hz..............  4% of pt. or 4% of  2% of pt. or 2% of  1% of max.
                                                                                               meas.               meas.
Gravimetric PM balance..........  mPM...............  N/A...............  N/A...............  See Sec.            0.5 [mu]g.........  N/A.
                                                                                               1065.790.
Inertial PM balance.............  mPM...............  N/A...............  N/A...............  4% of pt. or 4% of  2% of pt. or 2% of  1% of max.
                                                                                               meas.               meas.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Accuracy, repeatability, and noise are all determined with the same collected data, as described in Sec.   1065.305, and based on absolute values.
  ``pt.'' refers to the overall flow-weighted mean value expected at the standard; ``max.'' refers to the peak value expected at the standard over any
  test interval, not the maximum of the instrument's range; ``meas'' refers to the actual flow-weighted mean measured over any test interval.

* * * * *

0
89. Section 1065.925 is amended by revising paragraphs (h)(1), (h)(2), 
and (h)(3) to read as follows:

Sec.  1065.925  PEMS preparation for field testing.

* * * * *
    (h) * * *
    (1) Select the HC analyzer range for measuring the maximum 
concentration expected at the HC standard.
    (2) Zero the HC analyzers using a zero gas or ambient air 
introduced at the analyzer port. When zeroing a FID, use the FID's 
burner air that would be used for in-use measurements (generally either 
ambient air or a portable source of burner air).
    (3) Span the HC analyzer using span gas introduced at the analyzer 
port.
* * * * *

Subpart K--[Amended]

0
90. Section 1065.1001 is amended by revising the introductory text and 
the definitions for ``Idle speed'', ``Percent (%)'', and ``Round'' and 
adding definitions for ``Electric power generation application'', 
``High-idle speed'', and ``High-speed governor'' in alphabetical order 
to read as follows:

[[Page 57468]]

Sec.  1065.1001  Definitions.

* * * * *
    Electric power generation application means an application whose 
purpose is to generate a precise frequency of electricity, which is 
characterized by an engine that controls engine speed very precisely. 
This would generally not apply to welders or portable home generators.
* * * * *
    High-idle speed means the engine speed at which an engine governor 
function controls engine speed with operator demand at maximum and with 
zero load applied. ``Warm high-idle speed'' is the high-idle speed of a 
warmed-up engine.
    High-speed governor means any device, system, or element of design 
that modulates the engine output torque for the purpose of limiting the 
maximum engine speed.
* * * * *
    Idle speed means the engine speed at which an engine governor 
function controls engine speed with operator demand at minimum and with 
minimum load applied (greater than or equal to zero). For engines 
without a governor function that controls idle speed, idle speed means 
the manufacturer-declared value for lowest engine speed possible with 
minimum load. This definition does not apply for operation designated 
as ``high-idle speed.'' ``Warm idle speed'' is the idle speed of a 
warmed-up engine.
* * * * *
    Percent (%) means a representation of exactly 0.01. Numbers 
expressed as percentages in this part (such as a tolerance of 2%) have infinite precision, so 2% and 2.000000000% have the same 
meaning. This means that where we specify some percentage of a total 
value, the calculated value has the same number of significant digits 
as the total value. For example, 2% of a span value where the span 
value is 101.3302 is 2.026604.
* * * * *
    Round means to apply the rounding convention specified in Sec.  
1065.20(e), unless otherwise specified.
* * * * *

0
91. Section 1065.1005 is amended by revising the introductory text and 
paragraphs (a), (e), (f)(2), and (g) to read as follows:

Sec.  1065.1005  Symbols, abbreviations, acronyms, and units of 
measure.

    The procedures in this part generally follow the International 
System of Units (SI), as detailed in NIST Special Publication 811, 
which we incorporate by reference in Sec.  1065.1010. See Sec.  1065.20 
for specific provisions related to these conventions. This section 
summarizes the way we use symbols, units of measure, and other 
abbreviations.
    (a) Symbols for quantities. This part uses the following symbols 
and units of measure for various quantities:

 
--------------------------------------------------------------------------------------------------------------------------------------------------------
      Symbol              Quantity                Unit                        Unit symbol                        Units in terms of SI base units
--------------------------------------------------------------------------------------------------------------------------------------------------------
[alpha]...........  atomic hydrogen to    mole per mole.......  mol/mol                                 1
                     carbon ratio.
A.................  area................  square meter........  m \2\                                   m \2\
A0................  intercept of least    ....................  ......................................  ................................................
                     squares regression.
A1................  slope of least        ....................  ......................................  ................................................
                     squares regression.
[beta]............  ratio of diameters..  meter per meter.....  m/m                                     1
[beta]............  atomic oxygen to      mole per mole.......  mol/mol                                 1
                     carbon ratio.
C#................  number of carbon      ....................  ......................................  ................................................
                     atoms in a molecule.
d.................  Diameter............  meter...............  m                                       m
DR................  dilution ratio......  mole per mol........  mol/mol                                 1
[egr].............  error between a       ....................  ......................................  ................................................
                     quantity and its
                     reference.
e.................  brake-specific        gram per kilowatt     g/(kW[middot]hr)                        g[middot]3.6-1[middot]10\6\[middot]m-
                     emission or fuel      hour.                                                         2[middot]kg[middot]s\2\
                     consumption.
F.................  F-test statistic....  ....................  ......................................  ................................................
f.................  frequency...........  hertz...............  Hz                                      s-1
fn................  angular speed         revolutions per       r/min                                   2[middot][pi][middot]60-1[middot] m[middot]m-
                     (shaft).              minute.                                                       1x[middot]s-1
[gamma]...........  ratio of specific     (joule per kilogram   (J/(kg[middot]K))/(J/(kg[middot]K))     1
                     heats.                kelvin) per (joule
                                           per kilogram
                                           kelvin).
K.................  correction factor...  ....................  ......................................  1
l.................  length..............  meter...............  m                                       m
[mu]..............  viscosity, dynamic..  pascal second.......  Pa[middot]s                             m-1[middot]kg[middot]s
M.................  molar mass\1\.......  gram per mole.......  g/mol                                   10-3[middot]kg[middot]mol-1
m.................  mass................  kilogram............  kg                                      kg
m.................  mass rate...........  kilogram per second.  kg/s                                    kg[middot]s-1
[nu]..............  viscosity, kinematic  meter squared per     m-2/s                                   m-2[middot]s-1
                                           second.
N.................  total number in       ....................  ......................................  ................................................
                     series.
n.................  amount of substance.  mole................  mol                                     mol
[eta].............  amount of substance   mole per second.....  mol/s                                   mol[middot]s-1
                     rate.
P.................  power...............  kilowatt............  kW                                      10\3\[middot]m\2\[middot]kg[middot]s-3
PF................  penetration fraction  ....................  ......................................  ................................................
p.................  pressure............  pascal..............  Pa                                      m-1[middot]kg[middot]s-2
[rho].............  mass density........  kilogram per cubic    kg/m\3\                                 kg[middot]m-3
                                           meter.
r.................  ratio of pressures..  pascal per pascal...  Pa/Pa                                   1
R2................  coefficient of        ....................  ......................................  ................................................
                     determination.
Ra................  average surface       micrometer..........  [mu]m                                   10--6 m
                     roughness.
Re#...............  Reynolds number.....  ....................  ......................................  ................................................
RF................  response factor.....  ....................  ......................................  ................................................
RH................  relative humidity...  ....................  ......................................  ................................................
[sigma]...........  non-biased standard   ....................  ......................................  ................................................
                     deviation.
S.................  Sutherland constant.  kelvin..............  K                                       K
SEE...............  standard estimate of  ....................  ......................................  ................................................
                     error.
T.................  absolute temperature  kelvin..............  K                                       K
T.................  Celsius temperature.  degree Celsius......  [deg]C                                  K-273.15
T.................  torque (moment of     newton meter........  N[middot]m                              m-2[middot]kg[middot]s-2
                     force).
t.................  time................  second..............  s                                       s
[Delta]t..........  time interval,        second..............  s                                       s
                     period, 1/frequency.

[[Page 57469]]

 
V.................  volume..............  cubic meter.........  m\3\                                    m\3\
V.................  volume rate.........  cubic meter per       m\3\/s                                  m\3\[middot]s-1
                                           second.
W.................  work................  kilowatt hour.......  kW[middot]hr                            3.6[middot]10-6[middot]m\2\[middot]kg[middot]s-2
wc................  carbon mass fraction  gram per gram.......  g/g                                     1
x.................  amount of substance   mole per mole.......  mol/mol                                 1
                     mole fraction \2\.
x8................  flow-weighted mean    mole per mole.......  mol/mol                                 1
                     concentration.
y.................  generic variable....  ....................  ......................................  ................................................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ See paragraph (f)(2) of this section for the values to use for molar masses. Note that in the cases of NOX and HC, the regulations specify effective
  molar masses based on assumed speciation rather than actual speciation.
\2\ Note that mole fractions for THC, THCE, NMHC, NMHCE, and NOTHC are expressed on a C1 equivalent basis.

* * * * *
    (e) Subscripts. This part uses the following subscripts to define a 
quantity:

------------------------------------------------------------------------
                 Subscript                            Quantity
------------------------------------------------------------------------
abs.......................................  absolute quantity.
act.......................................  actual condition.
air.......................................  air, dry.
atmos.....................................  atmospheric.
cal.......................................  calibration quantity.
CFV.......................................  critical flow venturi.
cor.......................................  corrected quantity.
dil.......................................  dilution air.
dexh......................................  diluted exhaust.
exh.......................................  raw exhaust.
exp.......................................  expected quantity.
hi,idle...................................  condition at high-idle.
i.........................................  an individual of a series.
idle......................................  condition at idle.
in........................................  quantity in.
init......................................  initial quantity, typically
                                             before an emission test.
j.........................................  an individual of a series.
max.......................................  the maximum (i.e., peak)
                                             value expected at the
                                             standard over a test
                                             interval; not the maximum
                                             of an instrument range.
meas......................................  measured quantity.
out.......................................  quantity out.
part......................................  partial quantity.
PDP.......................................  positive-displacement pump.
ref.......................................  reference quantity.
rev.......................................  revolution.
sat.......................................  saturated condition.
slip......................................  PDP slip.
span......................................  span quantity.
SSV.......................................  subsonic venturi.
std.......................................  standard condition.
test......................................  test quantity.
test,alt..................................  alternate test quantity.
uncor.....................................  uncorrected quantity.
zero......................................  zero quantity.
------------------------------------------------------------------------

     (f) * * *
    (2) This part uses the following molar masses or effective molar 
masses of chemical species:

------------------------------------------------------------------------
                                                              g/mol (10-
               Symbol                       Quantity          3. kg.mol-
                                                                  1)
------------------------------------------------------------------------
Mair...............................  molar mass of dry air      28.96559
                                      \1\.
MAr................................  molar mass of argon...       39.948
MC.................................  molar mass of carbon..      12.0107
MC3H8..............................  molar mass of propane.     44.09562
MCH4...............................  molar mass of methane.       16.043
MCO................................  molar mass of carbon        28.0101
                                      monoxide.
MCO2...............................  molar mass of carbon        44.0095
                                      dioxide.
MH.................................  molar mass of atomic        1.00794
                                      hydrogen.
MH2................................  molar mass of               2.01588
                                      molecular hydrogen.
MH2O...............................  molar mass of water...     18.01528
MHe................................  molar mass of helium..     4.002602
MN.................................  molar mass of atomic        14.0067
                                      nitrogen.
MN2................................  molar mass of               28.0134
                                      molecular nitrogen.
MNMHC..............................  effective molar mass      13.875389
                                      of nonmethane
                                      hydrocarbon \2\.
MNMHCE.............................  effective molar mass      13.875389
                                      of nonmethane
                                      equivalent
                                      hydrocarbon \2\.
MNOx...............................  effective molar mass        46.0055
                                      of oxides of nitrogen
                                      \3\.
MN2O...............................  molar mass of nitrous       44.0128
                                      oxide.
MO.................................  molar mass of atomic        15.9994
                                      oxygen.
MO2................................  molar mass of               31.9988
                                      molecular oxygen.
MS.................................  molar mass of sulfur..       32.065
MTHC...............................  effective molar mass      13.875389
                                      of total hydrocarbon
                                      \2\.
MTHCE..............................  effective molar mass     13.875389
                                      of total hydrocarbon
                                      equivalent \2\.
------------------------------------------------------------------------
\1\ See paragraph (f)(1) of this section for the composition of dry air.
 
\2\ The effective molar masses of THC, THCE, NMHC, and NMHCE are defined
  by an atomic hydrogen-to-carbon ratio, [alpha], of 1.85.
\3\ The effective molar mass of NOX is defined by the molar mass of
  nitrogen dioxide, NO2.

* * * * *
    (g) Other acronyms and abbreviations. This part uses the following 
additional abbreviations and acronyms:

ASTM American Society for Testing and Materials
BMD bag mini-diluter
BSFC brake-specific fuel consumption
CARB California Air Resources Board
CFR Code of Federal Regulations
CFV critical-flow venturi
CI compression-ignition
CITT Curb Idle Transmission Torque
CLD chemiluminescent detector
CVS constant-volume sampler
DF deterioration factor
ECM electronic control module
EFC electronic flow control
EGR exhaust gas recirculation
EPA Environmental Protection Agency
FEL Family Emission Limit
FID flame-ionization detector
GC gas chromatograph

[[Page 57470]]

GC-ECD gas chromatograph with an electron-capture detector
GC-FID gas chromatograph with a flame ionization detector
IBP initial boiling point
ISO International Organization for Standardization
LPG liquefied petroleum gas
NDIR nondispersive infrared
NDUV nondispersive ultraviolet
NIST National Institute for Standards and Technology
NMC nonmethane cutter
PDP positive-displacement pump
PEMS portable emission measurement system
PFD partial-flow dilution
PMP Polymethylpentene
pt. a single point at the mean value expected at the standard.
PTFE polytetrafluoroethylene (commonly known as TeflonTM)
RE rounding error
RESS rechargeable energy storage system
RMC ramped-modal cycle
RMS root-mean square
RTD resistive temperature detector
SSV subsonic venturi
SI spark-ignition
UCL upper confidence limit
UFM ultrasonic flow meter
U.S.C. United States Code

0
92. Section 1065.1010 is amended by revising the introductory text and 
paragraph (c) to read as follows:

Sec.  1065.1010  Reference materials.

    Certain material is incorporated by reference into this part with 
the approval of the Director of the Federal Register under 5 U.S.C. 
552(a) and 1 CFR part 51. To enforce any edition other than that 
specified in this section, the Environmental Protection Agency must 
publish a notice of the change in the Federal Register and the material 
must be available to the public. All approved material is available for 
inspection at U.S. EPA, Air and Radiation Docket and Information 
Center, 1301 Constitution Ave., NW., Room B102, EPA West Building, 
Washington, DC 20460, (202) 202-1744, and is available from the sources 
listed below. It is also available for inspection at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to 
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
* * * * *
    (c) NIST material. Table 3 of this section lists material from the 
National Institute of Standards and Technology that we have 
incorporated by reference. The first column lists the number and name 
of the material. The second column lists the section of this part where 
we reference it. Anyone may purchase copies of these materials from the 
Government Printing Office, Washington, DC 20402 or download them free 
from the Internet at http://www.nist.gov. Table 3 follows:

               Table 3 of Sec.   1065.1010--NIST Materials
------------------------------------------------------------------------
         Document number and name               Part 1065  reference
------------------------------------------------------------------------
NIST Special Publication 811, 2008          1065.20(a) and (e),
 Edition, Guide for the Use of the           1065.1005.
 International System of Units (SI), March
 2008.
NIST Technical Note 1297, 1994 Edition,     1065.1001.
 Guidelines for Evaluating and Expressing
 the Uncertainty of NIST Measurement
 Results, Barry N. Taylor and Chris E.
 Kuyatt.
------------------------------------------------------------------------

* * * * *

0
93. A new part 1066 is added to subchapter U to read as follows:

PART 1066--VEHICLE-TESTING PROCEDURES

Subpart A--Applicability and General Provisions
Sec.
1066.1 Applicability.
1066.2 Submitting information to EPA under this part.
1066.5 Overview of this part 1066 and its relationship to the 
standard-setting part.
1066.10 Other procedures.
1066.15 Overview of test procedures.
1066.20 Units of measure and overview of calculations.
1066.25 Recordkeeping.
Subpart B--Equipment, Fuel, and Gas Specifications
1066.101 Overview.
Subpart C--Dynamometer Specifications
1066.201 Dynamometer overview.
1066.210 Dynamometers.
1066.215 Summary of verification and calibration procedures for 
chassis dynamometers.
1066.220 Linearity verification.
1066.225 Roll runout and diameter verification procedure.
1066.230 Time verification procedure.
1066.235 Speed verification procedure.
1066.240 Torque transducer verification and calibration.
1066.245 Response time verification.
1066.250 Base inertia verification.
1066.255 Parasitic loss verification.
1066.260 Parasitic friction compensation evaluation.
1066.265 Acceleration and deceleration verification.
1066.270 Unloaded coastdown verification.
1066.280 Driver's aid.
Subpart D--Coastdown
1066.301 Overview of coastdown procedures.
1066.310 Coastdown procedures for heavy-duty vehicles.
Subpart E--Vehicle Preparation and Running a Test
1066.401 Overview.
1066.407 Vehicle preparation and preconditioning.
1066.410 Dynamometer test procedure.
1066.420 Pre-test verification procedures and pre-test data 
collection.
1066.425 Engine starting and restarting.
1066.430 Performing emission tests
Subpart F--Hybrids
1066.501 Overview.
Subpart G--Calculations
1066.601 Overview.
1066.610 Mass-based and molar-based exhaust emission calculations.
Subpart H--Definitions and Other Reference Material
1066.701 Definitions.
1066.705 Symbols, abbreviations, acronyms, and units of measure.
1066.710 Reference materials.

    Authority: 42 U.S.C. 7401-7671q.

Subpart A--Applicability and General Provisions

Sec.  1066.1  Applicability.

    (a) This part describes the procedures that apply to testing we 
require for the following vehicles:
    (1) Model year 2014 and later heavy-duty highway vehicles we 
regulate under 40 CFR part 1037 that are not subject to chassis testing 
for exhaust emissions under 40 CFR part 86.
    (2) [Reserved]
    (b) The procedures of this part may apply to other types of 
vehicles, as described in this part and in the standard-setting part.
    (c) The term ``you'' means anyone performing testing under this 
part other than EPA.
    (1) This part is addressed primarily to manufacturers of vehicles, 
but it applies equally to anyone who does testing under this part for 
such manufacturers.
    (2) This part applies to any manufacturer or supplier of test 
equipment, instruments, supplies, or any other goods or services 
related to the procedures, requirements, recommendations, or options in 
this part.
    (d) Paragraph (a) of this section identifies the parts of the CFR 
that define emission standards and other requirements for particular 
types of

[[Page 57471]]

vehicles. In this part, we refer to each of these other parts 
generically as the ''standard-setting part.'' For example, 40 CFR part 
1037 is the standard-setting part for heavy-duty highway vehicles.
    (e) Unless we specify otherwise, the terms ``procedures'' and 
``test procedures'' in this part include all aspects of vehicle 
testing, including the equipment specifications, calibrations, 
calculations, and other protocols and procedural specifications needed 
to measure emissions.
    (f) For additional information regarding these test procedures, 
visit our Web site at http://www.epa.gov, and in particular http://www.epa.gov/nvfel/testing/regulations.htm.

Sec.  1066.2  Submitting information to EPA under this part.

    (a) You are responsible for statements and information in your 
applications for certification, requests for approved procedures, 
selective enforcement audits, laboratory audits, production-line test 
reports, field test reports, or any other statements you make to us 
related to this part 1066. If you provide statements or information to 
someone for submission to EPA, you are responsible for these statements 
and information as if you had submitted them to EPA yourself.
    (b) In the standard-setting part and in 40 CFR 1068.101, we 
describe your obligation to report truthful and complete information 
and the consequences of failing to meet this obligation. See also 18 
U.S.C. 1001 and 42 U.S.C. 7413(c)(2). This obligation applies whether 
you submit this information directly to EPA or through someone else.
    (c) We may void any certificates or approvals associated with a 
submission of information if we find that you intentionally submitted 
false, incomplete, or misleading information. For example, if we find 
that you intentionally submitted incomplete information to mislead EPA 
when requesting approval to use alternate test procedures, we may void 
the certificates for all engine families certified based on emission 
data collected using the alternate procedures. This would also apply if 
you ignore data from incomplete tests or from repeat tests with higher 
emission results.
    (d) We may require an authorized representative of your company to 
approve and sign the submission, and to certify that all the 
information submitted is accurate and complete. This includes everyone 
who submits information, including manufacturers and others.
    (e) See 40 CFR 1068.10 for provisions related to confidential 
information. Note however that under 40 CFR 2.301, emission data is 
generally not eligible for confidential treatment.
    (f) Nothing in this part should be interpreted to limit our ability 
under Clean Air Act section 208 (42 U.S.C. 7542) to verify that 
vehicles conform to the regulations.

Sec.  1066.5  Overview of this part 1066 and its relationship to the 
standard-setting part.

    (a) This part specifies procedures that can apply generally to 
testing various categories of vehicles. See the standard-setting part 
for directions in applying specific provisions in this part for a 
particular type of vehicle. Before using this part's procedures, read 
the standard-setting part to answer at least the following questions:
    (1) What drive schedules must I use for testing?
    (2) Should I warm up the test vehicle before measuring emissions, 
or do I need to measure cold-start emissions during a warm-up segment 
of the duty cycle?
    (3) Which exhaust constituents do I need to measure? Measure all 
exhaust constituents that are subject to emission standards, any other 
exhaust constituents needed for calculating emission rates, and any 
additional exhaust constituents as specified in the standard-setting 
part. We may approve your request to omit measurement of N2O 
and CH4 for a vehicle, provided it is not subject to an 
N2O or CH4 emission standard and we determine 
that other information is available to give us a reasonable basis for 
estimating or approximating the vehicle's emission rates.
    (4) Do any unique specifications apply for test fuels?
    (5) What maintenance steps may I take before or between tests on an 
emission-data vehicle?
    (6) Do any unique requirements apply to stabilizing emission levels 
on a new vehicle?
    (7) Do any unique requirements apply to test limits, such as 
ambient temperatures or pressures?
    (8) Is field testing required or allowed, and are there different 
emission standards or procedures that apply to field testing?
    (9) Are there any emission standards specified at particular 
operating conditions or ambient conditions?
    (10) Do any unique requirements apply for durability testing?
    (b) The testing specifications in the standard-setting part may 
differ from the specifications in this part. In cases where it is not 
possible to comply with both the standard-setting part and this part, 
you must comply with the specifications in the standard-setting part. 
The standard-setting part may also allow you to deviate from the 
procedures of this part for other reasons.
    (c) The following table shows how this part divides testing 
specifications into subparts:

                           Table 1 of Sec.   1066.5--Description of Part 1066 Subparts
----------------------------------------------------------------------------------------------------------------
            This subpart                             Describes these specifications or procedures
----------------------------------------------------------------------------------------------------------------
Subpart A...........................  Applicability and general provisions.
Subpart B...........................  Equipment for testing.
Subpart C...........................  Dynamometer specifications.
Subpart D...........................  Coastdowns for testing.
Subpart E...........................  How to prepare your vehicle and run an emission test.
Subpart F...........................  How to test hybrid vehicles.
Subpart G...........................  Test procedure calculations.
Subpart H...........................  Definitions and reference material.
----------------------------------------------------------------------------------------------------------------

Sec.  1066.10  Other procedures.

    (a) Your testing. The procedures in this part apply for all testing 
you do to show compliance with emission standards, with certain 
exceptions listed in this section. In some other sections in this part, 
we allow you to use other procedures (such as less precise or less 
accurate procedures) if they do not affect your ability to show that 
your vehicles comply with the applicable emission standards. This 
generally requires emission levels to be far enough below the 
applicable emission standards so that any errors caused by

[[Page 57472]]

greater imprecision or inaccuracy do not affect your ability to state 
unconditionally that the engines meet all applicable emission 
standards.
    (b) Our testing. These procedures generally apply for testing that 
we do to determine if your vehicles comply with applicable emission 
standards. We may perform other testing as allowed by the Act.
    (c) Exceptions. We may allow or require you to use procedures other 
than those specified in this part for laboratory testing, field 
testing, or both, as described in 40 CFR 1065.10(c). All the test 
procedures noted as exceptions to the specified procedures are 
considered generically as ``other procedures.'' Note that the terms 
``special procedures'' and ``alternate procedures'' have specific 
meanings; ``special procedures'' are those allowed by 40 CFR 
1065.10(c)(2) and ``alternate procedures'' are those allowed by 40 CFR 
1065.10(c)(7). If we require you to request approval to use other 
procedures under this paragraph (c), you may not use them until we 
approve your request.

Sec.  1066.15  Overview of test procedures.

    This section outlines the procedures to test vehicles that are 
subject to emission standards.
    (a) In the standard-setting part, we set emission standards in g/
mile (or g/km), for the following constituents:
    (1) Total oxides of nitrogen, NOX.
    (2) Hydrocarbons (HC), which may be expressed in the following 
ways:
    (i) Total hydrocarbons, THC.
    (ii) Nonmethane hydrocarbons, NMHC, which results from subtracting 
methane (CH4) from THC.
    (iii) Total hydrocarbon-equivalent, THCE, which results from 
adjusting THC mathematically to be equivalent on a carbon-mass basis.
    (iv) Nonmethane hydrocarbon-equivalent, NMHCE, which results from 
adjusting NMHC mathematically to be equivalent on a carbon-mass basis.
    (3) Particulate mass, PM.
    (4) Carbon monoxide, CO.
    (b) Note that some vehicles may not be subject to standards for all 
the emission constituents identified in paragraph (a) of this section.
    (c) We generally set emission standards over test intervals and/or 
drive schedules, as follows:
    (1) Vehicle operation. Testing may involve measuring emissions and 
miles travelled in a laboratory-type environment or in the field. The 
standard-setting part specifies how test intervals are defined for 
field testing. Refer to the definitions of ``duty cycle'' and ``test 
interval'' in Sec.  1066.701. Note that a single drive schedule may 
have multiple test intervals and require weighting of results from 
multiple test phases to calculate a composite distance-based emission 
value to compare to the standard.
    (2) Constituent determination. Determine the total mass of each 
constituent over a test interval by selecting from the following 
methods:
    (i) Continuous sampling. In continuous sampling, measure the 
constituent's concentration continuously from raw or dilute exhaust. 
Multiply this concentration by the continuous (raw or dilute) flow rate 
at the emission sampling location to determine the constituent's flow 
rate. Sum the constituent's flow rate continuously over the test 
interval. This sum is the total mass of the emitted constituent.
    (ii) Batch sampling. In batch sampling, continuously extract and 
store a sample of raw or dilute exhaust for later measurement. Extract 
a sample proportional to the raw or dilute exhaust flow rate, as 
applicable. You may extract and store a proportional sample of exhaust 
in an appropriate container, such as a bag, and then measure HC, CO, 
and NOX concentrations in the container after the test 
phase. You may deposit PM from proportionally extracted exhaust onto an 
appropriate substrate, such as a filter. In this case, divide the PM by 
the amount of filtered exhaust to calculate the PM concentration. 
Multiply batch sampled concentrations by the total (raw or dilute) flow 
from which it was extracted during the test interval. This product is 
the total mass of the emitted constituent.
    (iii) Combined sampling. You may use continuous and batch sampling 
simultaneously during a test interval, as follows:
    (A) You may use continuous sampling for some constituents and batch 
sampling for others.
    (B) You may use continuous and batch sampling for a single 
constituent, with one being a redundant measurement, subject to the 
provisions of 40 CFR 1065.201.
    (d) Refer to the standard-setting part for calculations to 
determine g/mile emission rates.
    (e) The regulation highlights several specific cases where good 
engineering judgment is especially relevant. You must use good 
engineering judgment for all aspects of testing under this part, not 
only for those provisions where we specifically re-state this 
requirement.

Sec.  1066.20  Units of measure and overview of calculations.

    (a) System of units. The procedures in this part follows both 
conventional English Units and the International System of Units (SI), 
as detailed in NIST Special Publication 811, which we incorporate by 
reference in Sec.  1066.710.
    (b) Units conversion. Use good engineering judgment to convert 
units between measurement systems as needed. The following conventions 
are used throughout this document and should be used to convert units 
as applicable:
    (1) 1 hp = 33,000 ft[middot]lbf/min = 550 ft[middot]lbf/s = 0.7457 
kW.
    (2) 1 lbf = 32.174 ft[middot]lbm/s\2\ = 4.4482 N.
    (3) 1 inch = 25.4 mm.
    (c) Rounding. The rounding provisions of 40 CFR 1065.20 apply for 
calculations in this part. This generally specifies that you round 
final values but not intermediate values. Use good engineering judgment 
to record the appropriate number of significant digits for all 
measurements.
    (d) Interpretation of ranges. Interpret a range as a tolerance 
unless we explicitly identify it as an accuracy, repeatability, 
linearity, or noise specification. See 40 CFR 1065.1001 for the 
definition of tolerance. In this part, we specify two types of ranges:
    (1) Whenever we specify a range by a single value and corresponding 
limit values above and below that value, target any associated control 
point to that single value. Examples of this type of range include 
``10% of maximum pressure'', or ``(30 10) 
kPa''.
    (2) Whenever we specify a range by the interval between two values, 
you may target any associated control point to any value within that 
range. An example of this type of range is ``(40 to 50) kPa''.
    (e) Scaling of specifications with respect to an applicable 
standard. Because this part 1066 applies to a wide range of vehicles 
and emission standards, some of the specifications in this part are 
scaled with respect to a vehicle's applicable standard or weight. This 
ensures that the specification will be adequate to determine 
compliance, but not overly burdensome by requiring unnecessarily high-
precision equipment. Many of these specifications are given with 
respect to a ``flow-weighted mean'' that is expected at the standard or 
during testing. Flow-weighted mean is the mean of a quantity after it 
is weighted proportional to a corresponding flow rate. For example, if 
a gas concentration is measured continuously from the raw exhaust of an 
engine, its flow-weighted mean

[[Page 57473]]

concentration is the sum of the products of each recorded concentration 
times its respective exhaust flow rate, divided by the sum of the 
recorded flow rates. As another example, the bag concentration from a 
CVS system is the same as the flow-weighted mean concentration, because 
the CVS system itself flow-weights the bag concentration. Refer to 40 
CFR 1065.602 for information needed to estimate and calculate flow-
weighted means.

Sec.  1066.25  Recordkeeping.

    The procedures in this part include various requirements to record 
data or other information. Refer to the standard-setting part regarding 
recordkeeping requirements. If the standard-setting part does not 
specify recordkeeping requirements, store these records in any format 
and on any media and keep them readily available for one year after you 
send an associated application for certification, or one year after you 
generate the data if they do not support an application for 
certification. You must promptly send us organized, written records in 
English if we ask for them. We may review them at any time.

Subpart B--Equipment, Fuel, and Gas Specifications

Sec.  1066.101  Overview.

    (a) This subpart addresses equipment related to emission testing, 
as well as test fuels and analytical gases. This section addresses 
emission sampling and analytical equipment, test fuels, and analytical 
gases.
    (b) The provisions of 40 CFR part 1065 specify engine-based 
procedures for measuring emissions. Except as specified otherwise in 
this part, the provisions of 40 CFR part 1065 apply for testing 
required by this part as follows:
    (1) The provisions of 40 CFR 1065.140 through 1065.195 specify 
equipment for exhaust dilution and sampling systems.
    (2) The provisions of 40 CFR part 1065, subparts C and D, specify 
measurement instruments and their calibrations.
    (3) The provisions of 40 CFR part 1065, subpart H, specify fuels, 
engine fluids, and analytical gases.
    (4) The provisions of 40 CFR part 1065, subpart J, describe how to 
measure emissions from vehicles operating outside of a laboratory, 
except that provisions related to measuring engine work do not apply.
    (c) The provisions of this subpart are intended to specify systems 
that can very accurately and precisely measure emissions from motor 
vehicles. We may waive or modify the specifications and requirements of 
this part for testing highway motorcycles or nonroad vehicles, 
consistent with good engineering judgment. For example, it may be 
appropriate to allow the use of a hydrokinetic dynamometer that is not 
able to meet all the performance specifications described in this 
subpart.

Subpart C--Dynamometer Specifications

Sec.  1066.201  Dynamometer overview.

    This subpart addresses chassis dynamometers and related equipment.

Sec.  1066.210  Dynamometers.

    (a) General requirements. A chassis dynamometer typically uses 
electrically generated load forces combined with its rotational inertia 
to recreate the mechanical inertia and frictional forces that a vehicle 
exerts on road surfaces (known as ``road load''). Load forces are 
calculated using vehicle-specific coefficients and response 
characteristics. The load forces are applied to the vehicle tires by 
rolls connected to intermediate motor/absorbers. The dynamometer uses a 
load cell to measure the forces the dynamometer rolls apply to the 
vehicle's tires.
    (b) Accuracy and precision. The dynamometer's output values for 
road load must be NIST-traceable. We may determine traceability to a 
specific international standards organization to be sufficient to 
demonstrate NIST-traceability. The force-measurement system must be 
capable of indicating force readings to a resolution of 0.05% of the maximum forces simulated by the dynamometer or 
0.9 N (0.2 lbf), whichever is greater, during a 
test.
    (c) Test cycles. The dynamometer must be capable of fully 
simulating applicable test cycles for the vehicles being tested as 
referenced in the corresponding standard-setting part.
    (1) For vehicles with a gross vehicle weight rating (GVWR) at or 
below 14,000 lbs, the dynamometer must be able to fully simulate a 
driving schedule with a maximum speed of 36 m/s (80 mph) and a maximum 
acceleration rate of 3.6 m/s\2\ (8 mph/s) in two-wheel drive and four-
wheel drive configurations.
    (2) For vehicles with GVWR above 14,000 lbs, the dynamometer must 
be able to fully simulate a driving schedule with a maximum speed of 29 
m/s (65 mph) and a maximum acceleration rate of 1.3 m/s\2\ (3 mph/s) in 
either two-wheel drive or four-wheel drive configurations.
    (d) Component requirements. The dynamometer must meet the following 
specifications:
    (1) For vehicles with GVWR at or below 14,000 lbs, the nominal roll 
diameter must be 1.20 to 1.25 meters. The dynamometer must have an 
independent drive roll for each axle being driven by the vehicle during 
an emission test.
    (2) For vehicles with GVWR above 14,000 lbs, the nominal roll 
diameter must be at least 1.20 meters and no greater than 3.10 meters. 
The dynamometer must have an independent drive roll for each axle, 
except that two drive axles may share a single drive roll. Use good 
engineering judgment to ensure that the dynamometer roll diameter is 
large enough to provide sufficient tire-roll contact area to avoid tire 
overheating and power losses from tire-roll slippage.
    (3) If you measure force and speed at 10 Hz or faster, you may use 
good engineering judgment to convert those measurements to 1-Hz, 2-Hz, 
or 5-Hz values.
    (4) The load applied by the dynamometer simulates forces acting on 
the vehicle during normal driving according to the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.080

Where:

FR = total road-load force to be applied at the surface of the roll. 
The total force is the sum of the individual tractive forces applied 
at each roll surface.
i = a counter to indicate a point in time over the driving schedule. 
For a dynamometer operating at 10-Hz intervals over a 600-

[[Page 57474]]

second driving schedule, the maximum value of i is 6,000.
A = constant value representing the vehicle's frictional load in lbf 
or newtons. See subpart C of this part.
B = coefficient representing load from drag and rolling resistance, 
which are a function of vehicle speed, in lbf/mph or N[middot]s/m. 
See subpart C of this part.
S = linear speed at the roll surfaces as measured by the 
dynamometer, in mph or m/s. Let Si-1 = 0.
C = coefficient representing aerodynamic effects, which are a 
function of vehicle speed squared, in lbf/mph\2\ or N[middot]s\2\/
m\2\. See subpart C of this part.
M = mass of vehicle in lbm or kg. Determine the vehicle's mass based 
on the test weight, taking into account the effect of rotating 
axles, as specified in Sec.  1066.310(b)(7) and dividing the weight 
by the acceleration due to gravity as specified in 40 CFR 1065.630, 
consistent with good engineering judgment.
t = elapsed time in the driving schedule as measured by the 
dynamometer, in seconds. Let ti-1 = 0.

    (5) The dynamometer must be designed to generally apply an actual 
road-load force within 1% or 9.8 N (2.2 lbf) of the reference value, whichever is greater. 
Dynamometers that do not fully meet this specification may be used 
consistent with good engineering judgment. For example, slightly higher 
errors may be permissible during highly transient operation.
    (e) Dynamometer manufacturer instructions. This part specifies that 
you follow the dynamometer manufacturer's recommended procedures for 
things such as calibrations and general operation. If you perform 
testing with a dynamometer that you manufactured or if you otherwise do 
not have these recommended procedures, use good engineering judgment to 
establish the additional procedures and specifications we specify in 
this part, unless we specify otherwise. Keep records to describe these 
recommended procedures and how they are consistent with good 
engineering judgment.

Sec.  1066.215  Summary of verification and calibration procedures for 
chassis dynamometers.

    (a) Overview. This section describes the overall process for 
verifying and calibrating the performance of chassis dynamometers.
    (b) Scope and frequency. The following table summarizes the 
required and recommended calibrations and verifications described in 
this subpart and indicates when they must occur:

Table 1 of Sec.   1066.215--Summary of Required Dynamometer Calibrations
                            and Verifications
------------------------------------------------------------------------
    Type of calibration or
         verification                    Minimum frequency \a\
------------------------------------------------------------------------
Sec.   1066.220: Linearity     Speed: Upon initial installation, within
 verification.                  370 days before testing, and after major
                                maintenance.
                               Torque (load): Upon initial installation,
                                within 370 days before testing, and
                                after major maintenance.
Sec.   1066.225: Roll runout   Upon initial installation and after major
 and diameter.                  maintenance.
Sec.   1066.230: Time........  Upon initial installation and after major
                                maintenance.
Sec.   1066.235: Speed         Upon initial installation, within 370
 measurement.                   days before testing, and after major
                                maintenance.
Sec.   1066.240: Torque        Upon initial installation and after major
 (load) transducer.             maintenance.
Sec.   1066.245: Response      Upon initial installation and after major
 time.                          maintenance.
Sec.   1066.250: Base inertia  Upon initial installation and after major
                                maintenance.
Sec.   1066.255: Parasitic     Upon initial installation, within 7 days
 loss.                          before testing, and after major
                                maintenance.
Sec.   1066.260: Parasitic     Upon initial installation, within 7 days
 friction compensation          before testing, and after major
 evaluation.                    maintenance.
Sec.   1066.265: Acceleration  Upon initial installation and after major
 and deceleration.              maintenance.
Sec.   1066.270: Unloaded      Upon initial installation, within 7 days
 coastdown.                     before testing, and after major
                                maintenance.
------------------------------------------------------------------------
\a\ Perform calibrations and verifications more frequently, according to
  measurement system manufacturer instructions and good engineering
  judgment.

    (c) Automated dynamometer verifications and calibrations. In some 
cases, dynamometers are designed with internal diagnostic and control 
features to accomplish the verifications and calibrations specified in 
this subpart. You may use these automated functions instead of 
following the procedures we specify in this subpart to demonstrate 
compliance with applicable requirements, consistent with good 
engineering judgment.
    (d) Sequence of verifications and calibrations. Upon initial 
installation and after major maintenance, perform the verifications and 
calibrations in the same sequence as noted in Table 1 of this section. 
At other times, you may need to perform specific verifications or 
calibration in a certain sequence, as noted in this subpart.
    (e) Corrections. Unless the regulation directs otherwise, if the 
dynamometer fails to meet any specified calibration or verification, 
make any necessary adjustments or repairs such that the dynamometer 
meets the specification before running a test. Repairs required to meet 
specifications are generally considered major maintenance under this 
part.

Sec.  1066.220  Linearity verification.

    (a) Scope and frequency. Perform linearity verifications upon 
initial installation, within 370 days before testing, and after major 
maintenance. Note that these linearity verifications may replace 
requirements previously referred to as calibrations. The intent of 
linearity verification is to determine that a measurement system 
responds accurately and proportionally over the measurement range of 
interest. Linearity verification generally consists of introducing a 
series of at least 10 reference values (or the manufacturer's recommend 
number of reference values) to a measurement system. The measurement 
system quantifies each reference value. The measured values are then 
collectively compared to the reference values by using a least-squares 
linear regression and the linearity criteria specified in Table 1 of 
this section.
    (b) Performance requirements. If a measurement system does not meet 
the applicable linearity criteria in Table 1 of this section, correct 
the deficiency by re-calibrating, servicing, or replacing components as 
needed. Repeat the linearity verification after correcting the 
deficiency to ensure that the measurement system meets the linearity 
criteria. Before you may use a measurement system that does not meet 
linearity criteria, you must demonstrate to us that the deficiency does 
not adversely affect your ability to demonstrate compliance with the 
applicable standards.
    (c) Procedure. Use the following linearity verification protocol, 
or use good engineering judgment to develop a

[[Page 57475]]

different protocol that satisfies the intent of this section, as 
described in paragraph (a) of this section:
    (1) In this paragraph (c), the letter ``y'' denotes a generic 
measured quantity, the superscript over-bar denotes an arithmetic mean 
(such as y), and the subscript ``ref'' denotes the known or 
reference quantity being measured.
    (2) Operate a dynamometer system at the specified temperatures and 
pressures. This may include any specified adjustment or periodic 
calibration of the dynamometer system.
    (3) Set dynamometer speed and torque to zero and apply the 
dynamometer brake to ensure a zero-speed condition.
    (4) Span the dynamometer speed or torque signal.
    (5) After spanning, check for zero speed and torque. Use good 
engineering judgment to determine whether or not to rezero or re-span 
before continuing.
    (6) For both speed and torque, use the dynamometer manufacturer's 
recommendations and good engineering judgment to select reference 
values, yrefi, that cover a range of values that you expect 
would prevent extrapolation beyond these values during emission 
testing. We recommend selecting zero speed and zero torque as reference 
values for the linearity verification.
    (7) Use the dynamometer manufacturer's recommendations and good 
engineering judgment to select the order in which you will introduce 
the series of reference values. For example, you may select the 
reference values randomly to avoid correlation with previous 
measurements or the influence of hysteresis; you may select reference 
values in ascending or descending order to avoid long settling times of 
reference signals; or you may select values to ascend and then descend 
to incorporate the effects of any instrument hysteresis into the 
linearity verification.
    (8) Set the dynamometer to operate at a reference condition.
    (9) Allow time for the dynamometer to stabilize while it measures 
the reference values.
    (10) At a recording frequency of at least 1 Hz, measure speed and 
torque values for 30 seconds and record the arithmetic mean of the 
recorded values, yi. Refer to 40 CFR 1065.602 for an example 
of calculating an arithmetic mean.
    (11) Repeat the steps in paragraphs (c)(8) though (10) of this 
section until you measure speeds and torques at each of the reference 
conditions.
    (12) Use the arithmetic means, yi, and reference values, 
yrefi, to calculate least-squares linear regression 
parameters and statistical values to compare to the minimum performance 
criteria specified in Table 1 of this section. Use the calculations 
described in 40 CFR 1065.602. Using good engineering judgment, you may 
weight the results of individual data pairs (i.e., (yrefi,, 
yi)), in the linear regression calculations.

        Table 1 of Sec.   1066.220--Dynamometer Measurement Systems That Require Linearity Verifications
----------------------------------------------------------------------------------------------------------------
                                                Linearity criteria
                                              ---------------------
       Measurement system           Quantity   [verbarlm] xmin(a1-       a1              SEE              r2
                                                 1)+a0 [verbarlm]
----------------------------------------------------------------------------------------------------------------
Speed...........................            S  =0.990
                                                Smax.
Torque (load)...................            T  =0.990
----------------------------------------------------------------------------------------------------------------

Sec.  1066.225  Roll runout and diameter verification procedure.

    (a) Overview. This section describes the verification procedure for 
roll runout and roll diameter. Roll runout is a measure of the 
variation in roll radius around the circumference of the roll.
    (b) Scope and frequency. Perform these verifications upon initial 
installation and after major maintenance.
    (c) Roll runout procedure. Verify roll runout as follows:
    (1) Perform this verification with laboratory and dynamometer 
temperatures stable and at equilibrium. Release the roll brake and shut 
off power to the dynamometer. Remove any dirt, rubber, rust, and debris 
from the roll surface. Mark measurement locations on the roll surface 
using a permanent marker. Mark the roll at a minimum of four equally 
spaced locations across the roll width; we recommend taking 
measurements every 150 mm across the roll. Secure the marker to the 
deck plate adjacent to the roll surface and slowly rotate the roll to 
mark a clear line around the roll circumference. Repeat this process 
for all measurement locations.
    (2) Measure roll runout using a dial indicator with a probe that 
allows for measuring the position of the roll surface relative to the 
roll centerline as it turns through a complete revolution. The dial 
indicator must have a magnetic base assembly or other means of being 
securely mounted adjacent to the roll. The dial indicator must have 
sufficient range to measure roll runout at all points, with a minimum 
accuracy and precision of 0.025 mm. Calibrate the dial 
indicator according to the instrument manufacturer's instructions.
    (3) Position the dial indicator adjacent to the roll surface at the 
desired measurement location. Position the shaft of the dial indicator 
perpendicular to the roll such that the point of the dial indicator is 
slightly touching the surface of the roll and can move freely through a 
full rotation of the roll. Zero the dial indicator according to the 
instrument manufacturer's instructions. Avoid distortion of the runout 
measurement from the weight of a person standing on or near the mounted 
dial indicator.
    (4) Slowly turn the roll through a complete rotation and record the 
maximum and minimum values from the dial indicator. Calculate runout as 
the difference between these maximum and minimum values.
    (5) Repeat the steps in paragraphs (c)(3) and (4) of this section 
for all measurement locations.
    (6) The roll runout must be less than 0.25 mm at all measurement 
locations.
    (d) Diameter procedure. Verify roll diameter based on the following 
procedure, or an equivalent procedure based on good engineering 
judgment:
    (1) Prepare the laboratory and the dynamometer as specified in 
paragraph (c)(1) of this section.
    (2) Measure roll diameter using a Pi Tape[supreg]. Orient the Pi 
Tape[supreg] to the marker line at the desired measurement location 
with the Pi Tape[supreg] hook pointed outward. Temporarily secure the 
Pi Tape[supreg] to the roll near the hook end with adhesive tape. 
Slowly turn the roll, wrapping the Pi Tape[supreg] around the roll 
surface. Ensure that the Pi Tape[supreg] is flat and adjacent to the 
marker line around the full circumference of the roll. Attach a 2.26-kg 
weight to the hook of the Pi Tape[supreg] and position the roll so that 
the weight dangles freely. Remove the adhesive tape without disturbing 
the orientation or alignment of the Pi Tape[supreg].
    (3) Overlap the gage member and the vernier scale ends of the Pi 
Tape[supreg] to read the diameter measurement to the nearest 0.01 mm. 
Follow the

[[Page 57476]]

manufacturer's recommendation to correct the measurement to 20 [deg]C, 
if applicable.
    (4) Repeat the steps in paragraphs (d)(2) and (3) of this section 
for all measurement locations.
    (5) The measured roll diameter must be within 0.25 mm 
of the specified nominal value at all measurement locations. You may 
revise the nominal value to meet this specification, as long as you use 
the corrected nominal value for all calculations in this subpart.

Sec.  1066.230  Time verification procedure.

    (a) Overview. This section describes how to verify the accuracy of 
the dynamometer's timing device.
    (b) Scope and frequency. Perform this verification upon initial 
installation and after major maintenance.
    (c) Procedure. Perform this verification using one of the following 
procedures:
    (1) WWV method. You may use the time and frequency signal broadcast 
by NIST from radio station WWV as the time standard if the trigger for 
the dynamometer timing circuit has a frequency decoder circuit, as 
follows:
    (i) Dial station WWV at (303) 499-7111 and listen for the time 
announcement. Verify that the trigger started the dynamometer timer. 
Use good engineering judgment to minimize error in receiving the time 
and frequency signal.
    (ii) After at least 1000 seconds, re-dial station WWV and listen 
for the time announcement. Verify that the trigger stopped the 
dynamometer timer.
    (iii) Compare the measured elapsed time, yact, to the 
corresponding time standard, yref, to determine the time 
error, yerror, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.081

    (2) Ramping method. You may set up an operator-defined ramp 
function in the signal generator to serve as the time standard as 
follows:
    (i) Set up the signal generator to output a marker voltage at the 
peak of each ramp to trigger the dynamometer timing circuit. Output the 
designated marker voltage to start the verification period.
    (ii) After at least 1000 seconds, output the designated marker 
voltage to end the verification period.
    (iii) Compare the measured elapsed time between marker signals, 
yact, to the corresponding time standard, yref, 
to determine the time error, yerror, using Equation 
1066.230-1.
    (3) Dynamometer coastdown method. You may use a signal generator to 
output a known speed ramp signal to the dynamometer controller to serve 
as the time standard as follows:
    (i) Generate upper and lower speed values to trigger the start and 
stop functions of the coastdown timer circuit. Use the signal generator 
to start the verification period.
    (ii) After at least 1000 seconds, use the signal generator to end 
the verification period.
    (iii) Compare the measured elapsed time between trigger signals, 
yact, to the corresponding time standard, yref, 
to determine the time error, yerror, using Equation 
1066.230-1.
    (d) Performance evaluation. The time error determined in paragraph 
(c) of this section may not exceed 0.001%.

Sec.  1066.235  Speed verification procedure.

    (a) Overview. This section describes how to verify the accuracy and 
resolution of the dynamometer speed determination.
    (b) Scope and frequency. Perform this verification upon initial 
installation, within 370 days before testing, and after major 
maintenance.
    (c) Procedure. Use one of the following procedures to verify the 
accuracy and resolution of the dynamometer speed simulation:
    (1) Pulse method. Connect a universal frequency counter to the 
output of the dynamometer's speed-sensing device in parallel with the 
signal to the dynamometer controller. The universal frequency counter 
must be calibrated according to the instrument manufacturer's 
instructions and be capable of measuring with enough accuracy to 
perform the procedure as specified in this paragraph (c)(1). Make sure 
the instrumentation does not affect the signal to the dynamometer 
control circuits. Determine the speed error as follows:
    (i) Set the dynamometer to speed-control mode. Set the dynamometer 
speed to a value between 4.2 m/s and the maximum speed expected during 
testing; record the output of the frequency counter after 10 seconds. 
Determine the roll speed, Sact, using the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.082

Where:

    f = frequency of the dynamometer speed sensing device, in 
s-\1\, accurate to at least four significant figures.
droll = nominal roll diameter, in m, accurate to the 
nearest 0.01 mm, consistent with Sec.  1066.225(d).
n = the number of pulses per revolution from the dynamometer roll 
speed sensor.
    Example:

[fnof]-- = 2.9231 Hz = 2.9231 s-1
droll = 904.40 mm = 0.90440 m
n = 1 pulse/rev
[GRAPHIC] [TIFF OMITTED] TR15SE11.083

Sact = 8.3053 m/s

    (ii) Compare the calculated roll speed, Sact, to the 
corresponding speed set point, Sref, to determine a value 
for speed error, Serror, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.084

    Example:

Sact = 8.3053 m/s
Sref = 8.3000 m/s
Serror = 8.3053 - 8.3000 = 0.0053 m/s

    (2) Frequency method. Use the method described in this paragraph 
(c)(2) only if the dynamometer does not have a readily available output 
signal for speed sensing. Install a single piece of tape in the shape 
of an arrowhead on the surface of the dynamometer roll near the outer 
edge. Put a reference mark on the deck plate in line with the arrow. 
Install a stroboscope or photo tachometer on the deck plate and direct 
the flash toward the tape on the roll. The stroboscope or photo 
tachometer must be calibrated according to the instrument 
manufacturer's instructions and be capable of measuring with enough 
accuracy to perform the procedure as specified in this paragraph 
(c)(2). Determine the speed error as follows:
    (i) Set the dynamometer to speed control mode. Set the dynamometer 
speed to a value between 15 kph and the maximum speed expected during 
testing. Tune the stroboscope or photo tachometer until the signal 
matches the dynamometer roll speed. Record the frequency. Determine the 
roll speed, yact, using Equation 1066.235-1, using the 
stroboscope or photo tachometer's frequency for [fnof].
    (ii) Compare the calculated roll speed, yact, to the 
corresponding speed set point, yref, to determine a value 
for speed error, yerror, using Equation 1066.235-2.
    (d) Performance evaluation. The speed error determined in paragraph 
(c)

[[Page 57477]]

of this section may not exceed 0.02 m/s.

Sec.  1066.240  Torque transducer verification and calibration.

    Calibrate torque-measurement systems as described in 40 CFR 
1065.310.

Sec.  1066.245  Response time verification.

    (a) Overview. This section describes how to verify the 
dynamometer's response time.
    (b) Scope and frequency. Perform this verification upon initial 
installation and after major maintenance.
    (c) Procedure. Use the dynamometer's automated process to verify 
response time. Perform this test at two different inertia settings 
corresponding approximately to the minimum and maximum vehicle weights 
you expect to test. Use good engineering judgment to select road-load 
coefficients representing vehicles of the appropriate weight. Determine 
the dynamometer's settling response time, ts, based on the 
point at which there are no measured results more than 10% above or 
below the final equilibrium value, as illustrated in Figure 1 of this 
section. The observed settling response time must be less than 100 
milliseconds for each inertia setting.
[GRAPHIC] [TIFF OMITTED] TR15SE11.085

Sec.  1066.250  Base inertia verification.

    (a) Overview. This section describes how to verify the 
dynamometer's base inertia.
    (b) Scope and frequency. Perform this verification upon initial 
installation and after major maintenance.
    (c) Procedure. Verify the base inertia using the following 
procedure:
    (1) Warm up the dynamometer according to the dynamometer 
manufacturer's instructions. Set the dynamometer's road-load inertia to 
zero and motor the rolls to 5 mph. Apply a constant force to accelerate 
the roll at a nominal rate of 1 mph/s. Measure the elapsed time to 
accelerate from 10 to 40 mph, noting the corresponding speed and time 
points to the nearest 0.01 mph and 0.01 s. Also determine average force 
over the measurement interval.
    (2) Starting from a steady roll speed of 45 mph, apply a constant 
force to the roll to decelerate the roll at a nominal rate of 1 mph/s. 
Measure the elapsed time to decelerate from 40 to 10 mph, noting the 
corresponding speed and time points to the nearest 0.01 mph and 0.01 s. 
Also determine average force over the measurement interval.
    (3) Repeat the steps in paragraphs (c)(1) and (2) of this section 
for a total of five sets of results at the nominal acceleration rate 
and the nominal deceleration rate.
    (4) Use good engineering judgment to select two additional 
acceleration and deceleration rates that cover the middle and upper 
rates expected during testing. Repeat the steps in paragraphs (c)(1) 
through (3) of this section at each of these additional acceleration 
and deceleration rates.
    (5) Determine the base inertia, Ib, for each measurement 
interval using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.086

Where:

[[Page 57478]]

F = average dynamometer force over the measurement interval as 
measured by the dynamometer, in ft[middot]lbm/s\2\.
Sfinal = roll surface speed at the end of the measurement 
interval to the nearest 0.01 mph.
Sinitial = roll surface speed at the start of the 
measurement interval to the nearest 0.01 mph.
[Delta]t = elapsed time during the measurement interval to the 
nearest 0.01 s.
    Example:

F = 1.500 lbf = 48.26 ft[middot]lbm/s\2\
Sfinal = 40.00 mph = 58.67 ft/s
Sinitial = 10.00 mph = 14.67 ft/s
[Delta]t = 30.00 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.087

Ib = 32.90 lbm

    (6) Determine the arithmetic mean value of base inertia from the 
five measurements at each acceleration and deceleration rate. Calculate 
these six mean values as described in 40 CFR 1065.602(b).
    (7) Calculate the base inertia error, Iberror, for each 
measured base inertia, Ib, by comparing it to the 
manufacturer's stated base inertia, Ibref, using the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.088

    Example:

Ibref = 32.96 lbm
Ibact = 33.01 lbm
[GRAPHIC] [TIFF OMITTED] TR15SE11.089

Iberror = -0.15%

    (8) Calculate the inertia error for each mean value of base inertia 
from paragraph (c)(6) of this section. Use Equation 1066.265-2, 
substituting the mean base inertias associated with each acceleration 
and deceleration rate for the individual base inertias.
    (d) Performance evaluation. The dynamometer must meet the following 
specifications to be used for testing under this part:
    (1) The base inertia error determined under paragraph (c)(7) of 
this section may not exceed 0.50% relative to any 
individual value.
    (2) The base inertia error determined under paragraph (c)(8) of 
this section may not exceed 0.20% relative to any mean 
value.

Sec.  1066.255  Parasitic loss verification.

    (a) Overview. Verify and correct the dynamometer's parasitic loss. 
This procedure determines the dynamometer's internal losses that it 
must overcome to simulate road load. These losses are characterized in 
a parasitic loss curve that the dynamometer uses to apply compensating 
forces to maintain the desired road-load force at the roll surface.
    (b) Scope and frequency. Perform this verification upon initial 
installation, within 7 days of testing, and after major maintenance.
    (c) Procedure. Perform this verification by following the 
dynamometer manufacturer's specifications to establish a parasitic loss 
curve, taking data at fixed speed intervals to cover the range of 
vehicle speeds that will occur during testing. You may zero the load 
cell at the selected speed if that improves your ability to determine 
the parasitic loss. Parasitic loss forces may never be negative. Note 
that the torque transducers must be zeroed and spanned prior to 
performing this procedure.
    (d) Performance evaluation. In some cases, the dynamometer 
automatically updates the parasitic loss curve for further testing. If 
this is not the case, compare the new parasitic loss curve to the 
original parasitic loss curve from the dynamometer manufacturer or the 
most recent parasitic loss curve you programmed into the dynamometer. 
You may reprogram the dynamometer to accept the new curve in all cases, 
and you must reprogram the dynamometer if any point on the new curve 
departs from the earlier curve by more than 4.5 N (1.0 lbf).

Sec.  1066.260  Parasitic friction compensation evaluation.

    (a) Overview. This section describes how to verify the accuracy of 
the dynamometer's friction compensation.
    (b) Scope and frequency. Perform this verification upon initial 
installation, within 7 days before testing, and after major 
maintenance. Note that this procedure relies on proper verification or 
calibration of speed and torque, as described in Sec. Sec.  1066.235 
and1066.240. You must also first verify the dynamometer's parasitic 
loss curve as specified in Sec.  1066.255.
    (c) Procedure. Use the following procedure to verify the accuracy 
of the dynamometer's friction compensation:
    (1) Warm up the dynamometer as specified by the dynamometer 
manufacturer.
    (2) Perform a torque verification as specified by the dynamometer 
manufacturer. For torque verifications relying on shunt procedures, if 
the results do not conform to specifications, recalibrate the 
dynamometer using NIST-traceable standards as appropriate until the 
dynamometer passes the torque verification. Do not change the 
dynamometer's base inertia to pass the torque verification.
    (3) Set the dynamometer inertia to the base inertia with the road-
load coefficients A, B, and C set to 0. Set the dynamometer to speed-
control mode with a target speed of 10 mph or a higher speed 
recommended by the dynamometer manufacturer. Once the speed stabilizes 
at the target speed, switch the dynamometer from speed control to 
torque control and allow the roll to coast for 60 seconds. Record the 
initial and final speeds and the corresponding start and stop times. If 
friction compensation is executed perfectly, there will be no change in 
speed during the measurement interval.
    (4) Calculate the friction compensation error, FCerror, 
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.090

Where:

I = dynamometer inertia setting, in lbf[middot]s\2\/ft.
t = duration of the measurement interval, accurate to at least 0.01 
s.
Sfinal = the roll speed corresponding to the end of the 
measurement interval, accurate to at least 0.1 mph.
Sinit = the roll speed corresponding to the start of the 
measurement interval, accurate to at least 0.1 mph.
    Example:

I = 2000 lbm = 62.16 lbf[middot] s\2\/ft
t = 60.0 s
Sfinal = 9.2 mph = 13.5 ft/s
Sinit = 10.0 mph = 14.7 ft/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.091

FCerror = -16.5 ft[middot]lbf/s = -0.031 hp

    (5) The friction compensation error may not exceed 0.1 
hp.

Sec.  1066.265  Acceleration and deceleration verification.

    (a) Overview. This section describes how to verify the 
dynamometer's ability to achieve targeted acceleration and deceleration 
rates. Paragraph (c) of this section describes how this verification 
applies when the dynamometer is programmed directly for a specific 
acceleration or deceleration rate. Paragraph (d) of this section 
describes

[[Page 57479]]

how this verification applies when the dynamometer is programmed with a 
calculated force to achieve a targeted acceleration or deceleration 
rate.
    (b) Scope and frequency. Perform this verification upon initial 
installation and after major maintenance.
    (c) Verification of acceleration and deceleration rates. Activate 
the dynamometer's function generator for measuring roll revolution 
frequency. If the dynamometer has no such function generator, set up a 
properly calibrated external function generator consistent with the 
verification described in this paragraph (c). Use the function 
generator to determine actual acceleration and deceleration rates as 
the dynamometer traverses speeds between 10 and 40 mph at various 
nominal acceleration and deceleration rates. Verify the dynamometer's 
acceleration and deceleration rates as follows:
    (1) Set up start and stop frequencies specific to your dynamometer 
by identifying the roll-revolution frequency, f, in revolutions per 
second (or Hz) corresponding to 10 mph and 40 mph vehicle speeds, 
accurate to at least four significant figures, using the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.092

Where:

S = the target roll speed, in inches per second (corresponding to 
drive speeds of 10 mph or 40 mph).
n = the number of pulses from the dynamometer's roll-speed sensor 
per roll revolution.
droll = roll diameter, in inches.

    (2) Program the dynamometer to accelerate the roll at a nominal 
rate of 1 mph/s from 10 mph to 40 mph. Measure the elapsed time to 
reach the target speed, to the nearest 0.01 s. Repeat this measurement 
for a total of five runs. Determine the actual acceleration rate for 
each run, aact, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.093

Where:

aact = acceleration rate (decelerations have negative 
values).
Sfinal = the target value for the final roll speed.
Sinit = the setpoint value for the initial roll speed.
t = time to accelerate from Sinit to Sfinal.

    Example:

Sinal = 40 mph
Sinit = 10 mph
t = 30.003 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.094

aact = 0.999 mph/s

    (3) Program the dynamometer to decelerate the roll at a nominal 
rate of 1 mph/s from 40 mph to 10 mph. Measure the elapsed time to 
reach the target speed, to the nearest 0.01 s. Repeat this measurement 
for a total of five runs. Determine the actual acceleration rate, 
aact, using Equation 1066.265-2.
    (4) Repeat the steps in paragraphs (c)(2) and (3) of this section 
for additional acceleration and deceleration rates in 1 mph/s 
increments up to and including one increment above the maximum 
acceleration rate expected during testing. Average the five repeat runs 
to calculate a mean acceleration rate, aact, at each 
setting.
    (5) Compare each mean acceleration rate, aact, to the 
corresponding nominal acceleration rate, aref, to determine 
values for acceleration error, aerror, using the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.095

    Example:

aact = 0.999 mph/s
aref = 1 mph/s
aerror = -0.100%

    (d) Verification of forces for controlling acceleration and 
deceleration. Program the dynamometer with a calculated force value and 
determine actual acceleration and deceleration rates as the dynamometer 
traverses speeds between 10 and 40 mph at various nominal acceleration 
and deceleration rates. Verify the dynamometer's ability to achieve 
certain acceleration and deceleration rates with a given force as 
follows:
    (1) Calculate the force setting, F, using the following equation:
    [GRAPHIC] [TIFF OMITTED] TR15SE11.096
    
Where:

Ib = the dynamometer manufacturer's stated base inertia, 
in lbf[middot]s\2\/ft.
a = nominal acceleration rate, in ft/s\2\.

    Example:

Ib = 2967 lbm = 92.217 lbf[middot]s\2\/ft
a = 1 mph/s = 1.4667 ft/s\2\
F = 135.25 lbf

    (2) Set the dynamometer to road-load mode and program it with a 
calculated force to accelerate the roll at a nominal rate of 1 mph/s 
from 10 mph to 40 mph. Measure the elapsed time to reach the target 
speed, to the nearest 0.01 s. Repeat this measurement for a total of 
five runs. Determine the actual acceleration rate, aact, for 
each run using Equation 1066.265-2. Repeat this step to determine 
measured ``negative acceleration'' rates using a calculated force to 
decelerate the roll at a nominal rate of 1 mph/s from 40 mph to 10 mph. 
Average the five repeat runs to calculate a mean acceleration rate, 
aact, at each setting.
    (3) Repeat the steps in paragraph (d)(2) of this section for 
additional acceleration and deceleration rates as specified in 
paragraph (c)(4) of this section.
    (4) Compare each mean acceleration rate, aact, to the 
corresponding nominal acceleration rate, aref, to determine 
values for acceleration error, aerror, using Equation 
1066.265-4.
    (e) Performance evaluation. The acceleration error from paragraphs 
(c)(5) and (d)(4) of this section may not exceed 1.0%.

Sec.  1066.270  Unloaded coastdown verification.

    (a) Overview. Use force measurements to verify the dynamometer's 
settings based on coastdown procedures.
    (b) Scope and frequency. Perform this verification upon initial 
installation, within 7 days of testing, and after major maintenance.
    (c) Procedure. This procedure verifies the dynamometer's settings 
derived from coastdown testing. For dynamometers that have an automated 
process for this procedure, perform this evaluation by setting the 
initial speed and final speed and the inertial and road-load 
coefficients as required for each test, using good engineering judgment 
to ensure that these values properly represent in-use operation. Use 
the following procedure if your dynamometer does not perform this 
verification with an automated process:
    (1) Warm up the dynamometer as specified by the dynamometer 
manufacturer.
    (2) With the dynamometer in coastdown mode, set the dynamometer 
inertia for the smallest vehicle weight that you expect to test and set 
A, B, and C road-load coefficients to values typical of those used 
during testing. Program the dynamometer to operate at 10 mph. Perform a 
coastdown two times at this speed setting. Repeat these

[[Page 57480]]

coastdown steps in 10 mph increments up to and including one increment 
above the maximum speed expected during testing. You may stop the 
verification before reaching 0 mph, with any appropriate adjustments in 
calculating the results.
    (3) Repeat the steps in paragraph (c)(2) of this section with the 
dynamometer inertia set for the largest vehicle weight that you expect 
to test.
    (4) Determine the average coastdown force, F, for each speed and 
inertia setting using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.097

Where:
F = the average force measured during the coastdown for each speed 
and inertia setting, expressed in lbf[middot]s\2\/ft and rounded to 
four significant figures.
I = the dynamometer's inertia setting, in lbf[middot]s\2\/ft.
Ssi = the speed setting at the start of the coastdown, 
expressed in ft/s and rounded to four significant figures.
t = coastdown time for each speed and inertia setting, accurate to 
at least 0.01 s.

    Example:

I = 2000 lbm = 65.17 lbf[middot]s\2\/ft
Ssi = 10 mph = 14.66 ft/s
t = 5.00 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.098

F = 191 lbf

    (5) Calculate the target value of coastdown force, Fref, 
based on the applicable dynamometer parameters for each speed and 
inertia setting.
    (6) Compare the mean value of the coastdown force measured for each 
speed and inertia setting, Fact, to the corresponding 
Fref to determine values for coastdown force error, 
Ferror, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.099

Example:
Fref = 192 lbf
Fact = 191 lbf
[GRAPHIC] [TIFF OMITTED] TR15SE11.100

Ferror = -0.5%

    (7) The maximum allowable error, Ferrormax, for all 
speed and inertia settings is calculated from the following formula, 
except that Ferrormax for vehicles with GVWR above 14,000 
lbs may be up to 1.0%:
    Ferrormax (%) = (2.2 lbf/Fref)[middot]100

Sec.  1066.280  Driver's aid.

    Use good engineering judgment to provide a driver's aid that 
facilitates compliance with the requirements of Sec.  1066.430.

Subpart D--Coastdown

Sec.  1066.301  Overview of coastdown procedures.

    (a) The coastdown procedures described in this subpart are used to 
determine the load coefficients (A, B, and C) for the simulated road-
load equation in Sec.  1066.210(d)(3).
    (b) The general procedure for performing coastdown tests and 
calculating load coefficients is described in SAE J1263 and SAE J2263 
(incorporated by reference in Sec.  1066.710). This subpart specifies 
certain deviations from those procedures for certain applications.
    (c) Use good engineering judgment for all aspects of coastdown 
testing. For example, minimize the effects of grade by performing 
coastdown testing on reasonably level surfaces and determining 
coefficients based on average values from vehicle operation in opposite 
directions over the course.

Sec.  1066.310  Coastdown procedures for heavy-duty vehicles.

    This section describes coastdown procedures that are unique to 
heavy-duty motor vehicles. Note as specified in the standard setting 
parts, this section does not apply for certain heavy-duty vehicles, 
such as those regulated under 40 CFR part 86, subpart S.
    (a) Determine load coefficients by performing a minimum of 16 valid 
coastdown runs (8 in each direction).
    (b) Follow the provisions of Sections 1 through 9 of SAE J1263, and 
SAE J2263 (incorporated by reference in Sec.  1066.710), except as 
described in this paragraph (b). The terms and variables identified in 
this paragraph (b) have the meaning given in SAE J1263 or J2263 unless 
specified otherwise.
    (1) The test condition specifications of SAE J1263 apply except as 
follows for wind and road conditions:
    (i) We recommend that you do not perform coastdown testing on days 
for which winds are forecast to exceed 6.0 mph.
    (ii) The grade of the test track or road must not be excessive 
(considering factors such as road safety standards and effects on the 
coastdown results). Road conditions should follow Section 7.4 of SAE 
J1263, except that road grade may exceed 0.5%. If road grade is greater 
than 0.02% over the length of the test surface, then the road grade as 
a function of distance along the length of the test surface must be 
incorporated in the analysis. To calculate the force due to grade use 
Section 11.5 of SAE J2263.
    (2) You must reach a top speed of greater than 70 mph such that 
data collection of the coastdown can start at or above 70 mph. Data 
collection must occur through a minimum speed at or below 15 mph. Data 
analysis for valid coastdown runs must include a maximum speed of 70 
mph and a minimum speed of 15 mph.
    (3) Gather data regarding wind speed and direction, in coordination 
with time-of-day data, using at least one stationary electro-mechanical 
anemometer and suitable data loggers meeting the specifications of SAE 
J1263, as well as the following additional specifications for the 
anemometer placed adjacent to the test surface:
    (i) Run the zero-wind and zero-angle calibration data collection.
    (ii) The anemometer must have had its outputs recorded at a wind 
speed of 0.0 mph within 24 hours before each coastdown test in which it 
is used.
    (iii) Record the location of the anemometer using a GPS measurement 
device adjacent to the test surface (approximately) at the midway 
distance along the test surface used for coastdowns.
    (iv) Position the anemometer such that it will be at least 2.5 but 
not more than 3.0 vehicle widths from the test vehicle's centerline as 
the test vehicle passes the location of that anemometer.
    (v) Mount the anemometer at a height that is within 6 inches of 
half the test vehicle's maximum height.
    (vi) Place the anemometer at least 50 feet from the nearest tree 
and at least 25 feet from the nearest bush (or equivalent roadside 
features).
    (vii) The height of the grass surrounding the stationary anemometer 
may not exceed 10% of the anemometer's mounted height, within a radius 
equal to the anemometer's mounted height.
    (4) You may split runs as per Section 9.3.1 of SAE J2263, but we 
recommend whole runs. If you split a run, analyze each portion 
separately, but count the split runs as one run with respect to the 
minimum number of runs required.
    (5) You may perform consecutive runs in a single direction, 
followed by consecutive runs in the opposite direction, consistent with 
good engineering judgment. Harmonize starting and stopping points to 
the

[[Page 57481]]

extent practicable to allow runs to be paired.
    (6) All valid coastdown run times in each direction must be within 
2.0 standard deviations of the mean of the valid coastdown run times 
(from 70 mph down to 15 mph) in that direction. Eliminate runs outside 
this range. After eliminating these runs you must have at least eight 
valid runs each direction.
    (7) Determine drag area, CDA, as follows instead of 
using the procedure specified in SAE J1263, Section 10:
    (i) Measure vehicle speed at fixed intervals over the coastdown run 
(generally at 10 Hz), including speeds at or above 15 mph and at or 
below 70 mph. Establish the height or altitude corresponding to each 
interval as described in SAE J2263 if you need to incorporate the 
effects of road grade.
    (ii) Calculate the vehicle's effective mass, Me, in kg 
by adding 56.7 kg to the vehicle mass for each tire making road 
contact. This accounts for the rotational inertia of the wheels and 
tires.
    (iii) Calculate the road-load force for each measurement interval, 
Fi, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.101

Where:
v = Vehicle speed at the beginning and end of the measurement 
interval. Let v0 = 0.
[Delta]t = Elapsed time over the measurement interval.

    (iv) Plot the data from all the coastdown runs on a single plot of 
Fi vs. vi\2\ to determine the slope correlation, 
D, based on the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.102

Where:
g = Gravitational acceleration = 9.81 m/s\2\.
[Delta]h = Change in height or altitude over the measurement 
interval, in m. Assume [Delta]h = 0 if you are not correcting for 
grade.
[Delta]s = Distance the vehicle travels down the road during the 
measurement interval, in m.
Am = the calculated value of the y-intercept based on the 
curve-fit.

    (v) Calculate drag area, CDA, in m2 using the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.103

Where:
[rho] = Air density at reference conditions = 1.17 kg/m\3\.
[GRAPHIC] [TIFF OMITTED] TR15SE11.104

T = Average ambient temperature during testing, in K.
PB = Average ambient pressuring during the test, in kPa.

    (8) Determine the A, B, and C coefficients identified in Sec.  
1066.210 as follows:
    A = Am
    B = 0
    C = Dadj

Subpart E--Vehicle Preparation and Running a Test

Sec.  1066.401  Overview.

    (a) Use the procedures detailed in this subpart to measure vehicle 
emissions over a specified drive schedule. This subpart describes how 
to:
    (1) Determine road-load power, test weight, and inertia class.
    (2) Prepare the vehicle, equipment, and measurement instruments for 
an emission test.
    (3) Perform pre-test procedures to verify proper operation of 
certain equipment and analyzers and to prepare them for testing.
    (4) Record pre-test data.
    (5) Sample emissions.
    (6) Record post-test data.
    (7) Perform post-test procedures to verify proper operation of 
certain equipment and analyzers.
    (8) Weigh PM samples.
    (b) An emission test generally consists of measuring emissions and 
other parameters while a vehicle follows the drive schedules specified 
in the standard-setting part. There are two general types of test 
cycles:
    (1) Transient cycles. Transient test cycles are typically specified 
in the standard-setting part as a second-by-second sequence of vehicle 
speed commands. Operate a vehicle over a transient cycle such that the 
speed follows the target values. Proportionally sample emissions and 
other parameters and use the calculations in 40 CFR part 86, subpart B, 
or 40 CFR part 1065, subpart G, to calculate emissions. The standard-
setting part may specify three types of transient testing based on the 
approach to starting the measurement, as follows:
    (i) A cold-start transient cycle where you start to measure 
emissions just before starting an engine that has not been warmed up.
    (ii) A hot-start transient cycle where you start to measure 
emissions just before starting a warmed-up engine.
    (iii) A hot running transient cycle where you start to measure 
emissions after an engine is started, warmed up, and running.
    (2) Cruise cycles. Cruise test cycles are typically specified in 
the standard-setting part as a discrete operating point that has a 
single speed command.
    (i) Start a cruise cycle as a hot running test, where you start to 
measure emissions after the engine is started and warmed up and the 
vehicle is running at the target test speed.
    (ii) Sample emissions and other parameters for the cruise cycle in 
the same manner as a transient cycle, with the exception that the 
reference speed value is constant. Record instantaneous and mean speed 
values over the cycle.

Sec.  1066.407  Vehicle preparation and preconditioning.

    This section describes steps to take before measuring exhaust 
emissions for those vehicles that are subject to evaporative or 
refueling emission tests as specified in the standard setting part. 
Other preliminary procedures may apply as specified in the standard-
setting part.
    (a) Prepare the vehicle for testing as described in 40 CFR 86.131.
    (b) If testing will include measurement of refueling emissions, 
perform the vehicle preconditioning steps as described in 40 CFR 
86.153. Otherwise, perform the vehicle preconditioning steps as 
described in 40 CFR 86.132.

Sec.  1066.410  Dynamometer test procedure.

    (a) Dynamometer testing may consist of multiple drive cycles with 
both cold-start and hot-start portions, including prescribed soak times 
before each test phase. See the standard-setting part for test cycles 
and soak times for the appropriate vehicle category. A test phase 
consists of engine startup (with accessories operated according to the 
standard-setting part), operation over the drive cycle, and engine 
shutdown.
    (b) During dynamometer operation, position a cooling fan that 
appropriately directs cooling air to the vehicle. This generally 
requires squarely positioning the fan within 30 centimeters of the 
front of the vehicle and directing the airflow to the vehicle's 
radiator.

[[Page 57482]]

    (1) For vehicles with GVWR at or below 14,000 lbs, you may use 
either of the following cooling fan configurations:
    (i) Use a fixed-speed fan to appropriately direct cooling air to 
the vehicle with the engine compartment cover open. The fan capacity 
may not exceed 2.50 m\3\/s. If you determine that additional cooling is 
needed to properly represent in-use operation, use good engineering 
judgment to increase the fan's capacity or use additional fans, subject 
to our approval.
    (ii) Use a road-speed modulated fan system that achieves a linear 
speed of cooling air at the blower outlet that is within 3.0 mph (1.3 m/s) of the corresponding roll speed 
when vehicle speeds are between 5 and 30 mph (2.2 to 13.4 m/s), and 
within 6.5 mph (2.9 m/s) of the corresponding 
roll speed at higher vehicle speeds. The fan must provide no cooling 
air for vehicle speeds below 5 mph, unless we approve your request to 
provide cooling during low-speed operation based on a demonstration 
that this is appropriate to simulate cooling for in-use vehicles. We 
recommend that the cooling fan have a minimum opening of 0.2 m\2\ and a 
minimum width of 0.8 m.
    (2) For vehicles with GVWR above 14,000 lbs, use a road-speed 
modulated fan system that achieves a linear speed of cooling air at the 
blower outlet that is within 3.0 mph (1.3 m/s) 
of the corresponding roll speed when vehicle speeds are between 5 and 
30 mph (2.2 to 13.4 m/s), and within 10 mph (4.5 m/s) of the corresponding roll speed at higher vehicle 
speeds. The fan must provide no cooling air for vehicle speeds below 5 
mph, unless we approve your request to provide cooling during low-speed 
operation based on a demonstration that this is appropriate to simulate 
the cooling experienced by in-use vehicles. We recommend that the 
cooling fan have a minimum opening of 2.75 m\2\, a minimum flow rate of 
3,600 m\3\/min at 50 mph, and that it maintain a minimum speed profile 
across the duct, in the free stream flow, of 15% of the 
target flow rate.
    (3) If the cooling specifications in this paragraph (b) are 
impractical for special vehicle designs, such as vehicles with rear-
mounted engines, you may arrange for an alternative fan configuration 
that allows for proper simulation of vehicle cooling during in-use 
operation, subject to our approval.
    (c) Record the vehicle's speed trace based on the time and speed 
data from the dynamometer. Record speed to at least the nearest 0.01 m/
s or 0.1 mph and time to at least the nearest 0.1 s.
    (d) You may perform practice runs for operating the vehicle and the 
dynamometer controls to meet the driving tolerances specified in Sec.  
1066.430 or adjust the emission sampling equipment. Verify that the 
accelerator pedal allows for enough control to closely follow the 
prescribed driving schedule. You may not measure emissions during a 
practice run.
    (e) Inflate the drive wheel tires according to the vehicle 
manufacturer's specifications. The drive wheels' tire pressure must be 
the same for dynamometer operation and for coastdown procedures for 
determining road-load coefficients. Report these tire pressure values 
with the test results.
    (f) For vehicles with GVWR above 14,000 lbs, you must use a vehicle 
pull down mechanism that allows simulation of the actual normal forces 
that the tire and dynamometer roll interface would see if a loaded 
vehicle were actually being tested. Use of this mechanism will ensure 
that wheel slip does not occur when trying to accelerate the loaded 
vehicle.
    (g) Use good engineering judgment when testing vehicles in four-
wheel drive or all-wheel drive mode. This may involve testing on a 
dynamometer with a separate dynamometer roll for each drive axle. This 
may also involve operation on a single roll, which may require 
disengaging the second set of drive wheels, either with a switch 
available to the driver or by some other means; however, operating such 
a vehicle on a single roll may occur only if this does not decrease 
emissions or energy consumption relative to normal in-use operation. 
Alternatively, for heavy-duty motor vehicles, up to two drive axles may 
use a single drive roll, as described in Sec.  1066.210(d)(2).
    (h) Warm up the dynamometer as recommended by the dynamometer 
manufacturer.
    (i) Following the test, determine the actual driving distance by 
counting the number of dynamometer roll or shaft revolutions, or by 
integrating speed over the course of testing from a high-resolution 
encoder system.

Sec.  1066.420  Pre-test verification procedures and pre-test data 
collection.

    (a) Follow the procedures for PM sample preconditioning and tare 
weighing as described in 40 CFR 1065.590 if your engine must comply 
with a PM standard.
    (b) Unless the standard-setting part specifies different 
tolerances, verify at some point before the test that ambient 
conditions are within the tolerances specified in this paragraph (b). 
For purposes of this paragraph (b), ``before the test'' means any time 
from a point just prior to engine starting (excluding engine restarts) 
to the point at which emission sampling begins.
    (1) Ambient temperature must be (20 to 30) [deg]C. See Sec.  
1066.430(m) for circumstances under which ambient temperatures must 
remain within this range during the test.
    (2) Atmospheric pressure must be (80.000 to 103.325) kPa. You are 
not required to verify atmospheric pressure prior to a hot-start test 
interval for testing that also includes a cold start.
    (3) Dilution air conditions must meet the specifications in 40 CFR 
1065.140, except in cases where you preheat your CVS before a cold-
start test. We recommend verifying dilution air conditions just before 
starting each test phase.
    (c) You may test vehicles at any intake-air humidity.
    (d) You may perform a final calibration of proportional-flow 
control systems, which may include performing practice runs.
    (e) You may perform the following procedure to precondition 
sampling systems:
    (1) Operate the vehicle over the test cycle.
    (2) Operate any dilution systems at their expected flow rates. 
Prevent aqueous condensation in the dilution systems.
    (3) Operate any PM sampling systems at their expected flow rates.
    (4) Sample PM for at least 10 min using any sample media. You may 
change sample media during preconditioning. You must discard 
preconditioning samples without weighing them.
    (5) You may purge any gaseous sampling systems during 
preconditioning.
    (6) You may conduct calibrations or verifications on any idle 
equipment or analyzers during preconditioning.
    (7) Proceed with the test sequence described in Sec.  1066.430.
    (f) Verify the amount of nonmethane hydrocarbon (or equivalent) 
contamination in the exhaust and background HC sampling systems within 
8 hours before the start of the first test drive cycle for each 
individual vehicle tested as described in 40 CFR 1065.520(g).

Sec.  1066.425  Engine starting and restarting.

    (a) Start the vehicle's engine as follows:
    (1) At the beginning of the test cycle, start the engine according 
to the procedure you describe in your owners manual. In the case of 
hybrid vehicles, this would generally involve activating vehicle 
systems such that the engine will start when the vehicle's control

[[Page 57483]]

algorithms determine that the engine should provide power instead of or 
in addition to power from the rechargeable energy storage system 
(RESS). Unless we specify otherwise, engine starting throughout this 
part generally refers to this step of activating the system on hybrid 
vehicles, whether or not that causes the engine to start running.
    (2) Place the transmission in gear as described by the test cycle 
in the standard-setting part. During idle operation, you may apply the 
brakes if necessary to keep the drive wheels from turning.
    (b) If the vehicle does not start after your recommended maximum 
cranking time, wait and restart cranking according to your recommended 
practice. If you don't recommend such a cranking procedure, stop 
cranking after 10 seconds, wait for 10 seconds, then start cranking 
gain for up to 10 seconds. You may repeat this for up to three start 
attempts. If the vehicle does not start after three attempts, you must 
determine and record the reason for failure to start. Shut off sampling 
systems and either turn the CVS off, or disconnect the exhaust tube 
from the tailpipe during the diagnostic period. Reschedule the vehicle 
for testing from a cold start.
    (c) Repeat the recommended starting procedure if the engine has a 
``false start.''
    (d) Take the following steps if the engine stalls:
    (1) If the engine stalls during an idle period, restart the engine 
immediately and continue the test. If you cannot restart the engine 
soon enough to allow the vehicle to follow the next acceleration, stop 
the driving schedule indicator and reactivate it when the vehicle 
restarts.
    (2) If the engine stalls during operation other than idle, stop the 
driving schedule indicator, restart the engine, accelerate to the speed 
required at that point in the driving schedule, reactivate the driving 
schedule indicator, and continue the test.
    (3) Void the test if the vehicle will not restart within one 
minute. If this happens, remove the vehicle from the dynamometer, take 
corrective action, and reschedule the vehicle for testing. Record the 
reason for the malfunction (if determined) and any corrective action. 
See the standard-setting part for instructions about reporting these 
malfunctions.

Sec.  1066.430  Performing emission tests.

    The overall test consists of prescribed sequences of fueling, 
parking, and driving at specified test conditions.
    (a) Vehicles are tested for criteria pollutants and greenhouse gas 
emissions as described in the standard-setting part.
    (b) Take the following steps before emission sampling begins:
    (1) For batch sampling, connect clean storage media, such as 
evacuated bags or tare-weighed filters.
    (2) Start all measurement instruments according to the instrument 
manufacturer's instructions and using good engineering judgment.
    (3) Start dilution systems, sample pumps, and the data-collection 
system.
    (4) Pre-heat or pre-cool heat exchangers in the sampling system to 
within their operating temperature tolerances for a test.
    (5) Allow heated or cooled components such as sample lines, 
filters, chillers, and pumps to stabilize at their operating 
temperatures.
    (6) Verify that there are no significant vacuum-side leaks 
according to 40 CFR 1065.345.
    (7) Adjust the sample flow rates to desired levels using bypass 
flow, if desired.
    (8) Zero or re-zero any electronic integrating devices before the 
start of any test interval.
    (9) Select gas analyzer ranges. You may automatically or manually 
switch gas analyzer ranges during a test only if switching is performed 
by changing the span over which the digital resolution of the 
instrument is applied. During a test you may not switch the gains of an 
analyzer's analog operational amplifier(s).
    (10) Zero and span all continuous gas analyzers using NIST-
traceable gases that meet the specifications of 40 CFR 1065.750. Span 
FID analyzers on a carbon number basis of one (C1). For 
example, if you use a C3H8 span gas of 
concentration 200 [mu]mol/mol, span the FID to respond with a value of 
600 [mu]mol/mol. Span FID analyzers consistent with the determination 
of their respective response factors, RF, and penetration fractions, 
PF, according to 40 CFR 1065.365.
    (11) We recommend that you verify gas analyzer responses after 
zeroing and spanning by sampling a calibration gas that has a 
concentration near one-half of the span gas concentration. Based on the 
results and good engineering judgment, you may decide whether or not to 
re-zero, re-span, or re-calibrate a gas analyzer before starting a 
test.
    (12) If you correct for dilution air background concentrations of 
associated engine exhaust constituents, start sampling and recording 
background concentrations.
    (13) Turn on cooling fans immediately before starting the test.
    (c) Operate vehicles during testing as follows:
    (1) Where we do not give specific instructions, operate the vehicle 
according to your recommendations in the owners manual, unless those 
recommendations are unrepresentative of what may reasonably be expected 
for in-use operation.
    (2) If vehicles have features that preclude dynamometer testing, 
modify these features as necessary to allow testing, consistent with 
good engineering judgment.
    (3) Operate vehicles during idle as follows:
    (i) For a vehicle with an automatic transmission, operate at idle 
with the transmission in ``Drive'' with the wheels braked, except that 
you may shift to ``Neutral'' for the first idle period and for any idle 
period longer than one minute. If you put the vehicle in ``Neutral'' 
during an idle, you must shift the vehicle into ``Drive'' with the 
wheels braked at least 5 seconds before the end of the idle period.
    (ii) For vehicles with manual transmission, operate at idle with 
the transmission in gear with the clutch disengaged, except that you 
may shift to ``Neutral'' with the clutch disengaged for the first idle 
period and for any idle period longer than one minute. If you put the 
vehicle in ``Neutral'' during idle, you must shift to first gear with 
the clutch disengaged at least 5 seconds before the end of the idle 
period.
    (4) Operate the vehicle with the appropriate accelerator pedal 
movement necessary to achieve the speed versus time relationship 
prescribed by the driving schedule. Avoid smoothing speed variations 
and excessive accelerator pedal perturbations.
    (5) Operate the vehicle smoothly, following representative shift 
speeds and procedures. For manual transmissions, the operator shall 
release the accelerator pedal during each shift and accomplish the 
shift with minimum time. If the vehicle cannot accelerate at the 
specified rate, operate it at maximum available power until the vehicle 
speed reaches the value prescribed for that time in the driving 
schedule.
    (6) Decelerate without changing gears, using the brakes or 
accelerator pedal as necessary to maintain the desired speed. Keep the 
clutch engaged on manual transmission vehicles and do not change gears 
after the end of the acceleration event. Depress manual transmission 
clutches when the speed drops below 6.7 m/s (15 mph), when engine

[[Page 57484]]

roughness is evident, or when engine stalling is imminent.
    (7) For test vehicles equipped with manual transmissions, shift 
gears in a way that represents reasonable shift patterns for in-use 
operation, considering vehicle speed, engine speed, and any other 
relevant variables. You may recommend a shift schedule in your owners 
manual that differs from your shift schedule during testing as long as 
you include both shift schedules in your application for certification. 
In this case, we may use the shift schedule you describe in your owners 
manual.
    (d) See the standard-setting part for drive schedules. These are 
defined by a smooth trace drawn through the specified speed vs. time 
sequence.
    (e) The driver must attempt to follow the target schedule as 
closely as possible, consistent with the specifications in paragraph 
(b) of this section. Instantaneous speeds must stay within the 
following tolerances:
    (1) The upper limit is 1.0 m/s (2 mph) higher than the highest 
point on the trace within 1.0 s of the given point in time.
    (2) The lower limit is 1.0 m/s (2 mph) lower than the lowest point 
on the trace within 1.0 s of the given time.
    (3) The same limits apply for vehicle preconditioning, except that 
the upper and lower limits for speed values are 2.0 m/s 
(4 mph).
    (4) Void the test if you do not maintain speed values as specified 
in this paragraph (e)(4). Speed variations (such as may occur during 
gear changes or braking spikes) may occur as follows, provided that 
such variations are clearly documented, including the time and speed 
values and the reason for the deviation:
    (i) Speed variations greater than the specified limits are 
acceptable for up to 2.0 seconds on any occasion.
    (ii) For vehicles that are not able to maintain acceleration as 
specified in paragraph (c)(5) of this section, do not count the 
insufficient acceleration as being outside the specified limits.
    (f) Figure 1 and Figure 2 of this section show the range of 
acceptable speed tolerances for typical points during testing. Figure 1 
of this section is typical of portions of the speed curve that are 
increasing or decreasing throughout the 2-second time interval. Figure 
2 of this section is typical of portions of the speed curve that 
include a maximum or minimum value.
BILLING CODE 4910-59-P

[[Page 57485]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.105

BILLING CODE 4910-59-c
    (g) Start testing as follows:
    (1) If a vehicle is already running and warmed up, and starting is 
not part of the test cycle, operate the vehicle as follows:

[[Page 57486]]

    (i) For transient test cycles, control vehicle speeds to follow a 
drive schedule consisting of a series of idles, accelerations, cruises, 
and decelerations.
    (ii) For cruise test cycles, control the vehicle operation to match 
the speed of the first phase of the test cycle. Follow the instructions 
in the standard-setting part to determine how long to stabilize the 
vehicle during each phase, how long to sample emissions at each phase, 
and how to transition between phases.
    (2) If engine starting is part of the test cycle, initiate data 
logging, sampling of exhaust gases, and integrating measured values 
before starting the engine. Initiate the driver's trace when the engine 
starts.
    (h) At the end of each test interval, continue to operate all 
sampling and dilution systems to allow the response times to elapse. 
Then stop all sampling and recording, including the recording of 
background samples. Finally, stop any integrating devices and indicate 
the end of the duty cycle in the recorded data.
    (i) Shut down the vehicle if it is part of the test cycle or if 
testing is complete.
    (j) If testing involves engine shutdown followed by another test 
phase, start a timer for the vehicle soak when the engine shuts down.
    (k) Take the following steps after emission sampling is complete:
    (1) For any proportional batch sample, such as a bag sample or PM 
sample, verify that proportional sampling was maintained according to 
40 CFR 1065.545. Void any samples that did not maintain proportional 
sampling according to specifications.
    (2) Place any used PM samples into covered or sealed containers and 
return them to the PM-stabilization environment. Follow the PM sample 
post-conditioning and total weighing procedures in 40 CFR 1065.595.
    (3) As soon as practical after the test cycle is complete, or 
optionally during the soak period if practical, perform the following:
    (i) Drift check all continuous gas analyzers and zero and span all 
batch gas analyzers no later than 30 minutes after the test cycle is 
complete, or during the soak period if practical.
    (ii) Analyze any conventional gaseous batch samples no later than 
30 minutes after a test phase is complete, or during the soak period if 
practical. Analyze nonconventional gaseous batch samples, such as NMHCE 
sampling with ethanol, as soon as practicable using good engineering 
judgment.
    (iii) Analyze background samples no later than 60 minutes after the 
test cycle is complete.
    (4) After quantifying exhaust gases, verify drift as follows:
    (i) For batch and continuous gas analyzers, record the mean 
analyzer value after stabilizing a zero gas to the analyzer. 
Stabilization may include time to purge the analyzer of any sample gas, 
plus any additional time to account for analyzer response.
    (ii) Record the mean analyzer value after stabilizing the span gas 
to the analyzer. Stabilization may include time to purge the analyzer 
of any sample gas, plus any additional time to account for analyzer 
response.
    (iii) Use these data to validate and correct for drift as described 
in 40 CFR 1065.550.
    (l) [Reserved]
    (m) Measure and record ambient temperature and pressure. Also 
measure humidity, as required, such as for correcting NOX 
emissions. For testing vehicles with the following engines, you must 
record ambient temperature continuously to verify that it remains 
within the temperature range specified in Sec.  1066.420(b)(1) 
throughout the test:
    (1) Air-cooled engines.
    (2) Engines equipped with emission control devices that sense and 
respond to ambient temperature.
    (3) Any other engine for which good engineering judgment indicates 
that this is necessary to remain consistent with 40 CFR 1065.10(c)(1).

Subpart F--Hybrids

Sec.  1066.501  Overview.

    To correct fuel economy or emission results for Net Energy Change 
of the RESS, use the procedures specified for charge-sustaining 
operation in SAE J2711 (incorporated by reference in Sec.  1066.710).

Subpart G--Calculations

Sec.  1066.601  Overview.

    (a) This subpart describes how to--
    (1) Use the signals recorded before, during, and after an emission 
test to calculate distance-specific emissions of each regulated 
pollutant.
    (2) Perform calculations for calibrations and performance checks.
    (3) Determine statistical values.
    (b) You may use data from multiple systems to calculate test 
results for a single emission test, consistent with good engineering 
judgment. You may also make multiple measurements from a single batch 
sample, such as multiple weighing of a PM filter or multiple readings 
from a bag sample. You may not use test results from multiple emission 
tests to report emissions. We allow weighted means where appropriate. 
You may discard statistical outliers, but you must report all results.

Sec.  1066.610  Mass-based and molar-based exhaust emission 
calculations.

    (a) Calculate your total mass of emissions over a test cycle as 
specified in 40 CFR 86.144 or 40 CFR part 1065, subpart G.
    (b) For composite emission calculations over multiple test phases 
and corresponding weighting factors, see the standard-setting part.

Subpart H--Definitions and Other Reference Material

Sec.  1066.701  Definitions.

    The definitions in this section apply to this part. The definitions 
apply to all subparts unless we note otherwise. Other terms have the 
meaning given in 40 CFR part 1065. The definitions follow:
    Base inertia means a value expressed in mass units to represent the 
rotational inertia of the rotating dynamometer components between the 
vehicle driving tires and the dynamometer torque-measuring device, as 
specified in Sec.  1066.250.
    Driving schedule means a series of vehicle speeds that a vehicle 
must follow during a test. Driving schedules are specified in the 
standard-setting part. A driving schedule may consist of multiple test 
phases.
    Duty cycle means a set of weighting factors and the corresponding 
test cycles, where the weighting factors are used to combine the 
results of multiple test phases into a composite result.
    Road-load coefficients means sets of A, B, and C road-load force 
coefficients that are used in the dynamometer road-load simulation, 
where road-load force at speed S equals A + B[middot]S + C[middot]S\2\.
    Test phase means a duration over which a vehicle's emission rates 
are determined for comparison to an emission standard. For example, the 
standard-setting part may specify a complete duty cycle as a cold-start 
test phase and a hot-start test phase. In cases where multiple test 
phases occur over a duty cycle, the standard-setting part may specify 
additional calculations that weight and combine results to arrive at 
composite values for comparison against the applicable standards.
    Test weight has the meaning given in the standard-setting part.
    Unloaded coastdown means a dynamometer coastdown run with the 
vehicle wheels off the roll surface.

Sec.  1066.705  Symbols, abbreviations, acronyms, and units of measure.

    The procedures in this part generally follow either the 
International System of

[[Page 57487]]

Units (SI) or the United States customary units, as detailed in NIST 
Special Publication 811, which we incorporate by reference in Sec.  
1066.710. See 40 CFR 1065.20 for specific provisions related to these 
conventions. This section summarizes the way we use symbols, units of 
measure, and other abbreviations.
    (a) Symbols for quantities. This part uses the following symbols 
and units of measure for various quantities:

--------------------------------------------------------------------------------------------------------------------------------------------------------
      Symbol                Quantity                   Unit                          Unit symbol                     Unit in terms of SI base units
--------------------------------------------------------------------------------------------------------------------------------------------------------
a.................  acceleration...........  feet per second squared  ft/s\2\ or m/s\2\                         m[middot]s-2
                                              or meters per second
                                              squared.
d.................  diameter...............  meters.................  m                                         m
F.................  force..................  pound force or newton..  lbf or N                                  kg[middot]s-2
f.................  frequency..............  hertz..................  Hz                                        s-1
I.................  inertia................  pound mass or kilogram.  lbm or kg                                 kg
i.................  indexing variable......  .......................  ........................................  ........................................
M.................  mass...................  pound mass or kilogram.  lbm or kg                                 kg
N.................  total number in series.  .......................  ........................................  ........................................
n.................  total number of pulses   .......................  ........................................  ........................................
                     in a series.
R.................  dynamometer roll         revolutions per minute.  rpm                                       2[middot][pi][middot]60-1[middot]
                     revolutions.                                                                                m[middot]m-1[middot]s-1
RL................  road-load coefficient..  horsepower or kilowatt.  hp or kW                                  10\3\[middot]m\2\[middot]kg[middot]s-3
S.................  speed..................  miles per hour or        mph or m/s                                m[middot]s-1
                                              meters per second.
T.................  Celsius temperature....  degree Celsius.........  [deg]C                                    K-273.15
T.................  torque (moment of        newton meter...........  N[middot]m                                m\2\[middot]kg[middot]s-2
                     force).
t.................  time...................  second.................  s                                         s
[Delta]t..........  time interval, period,   second.................  s                                         s
                     1/frequency.
y.................  generic variable.......  .......................  ........................................  ........................................
--------------------------------------------------------------------------------------------------------------------------------------------------------

    (b) Symbols for chemical species. This part uses the following 
symbols for chemical species and exhaust constituents:

------------------------------------------------------------------------
                 Symbol                              Species
------------------------------------------------------------------------
CH4....................................  methane
CO.....................................  carbon monoxide
CO2....................................  carbon dioxide
NMHC...................................  nonmethane hydrocarbon
NMHCE..................................  nonmethane hydrocarbon
                                          equivalent
NO.....................................  nitric oxide
NO2....................................  nitrogen dioxide
NOX....................................  oxides of nitrogen
N2O....................................  nitrous oxide
O2.....................................  molecular oxygen
PM.....................................  particulate mass
THC....................................  total hydrocarbon
THCE...................................  total hydrocarbon equivalent
------------------------------------------------------------------------

     (c) Superscripts. This part uses the following superscripts to 
define a quantity:

------------------------------------------------------------------------
                Superscript                           Quantity
------------------------------------------------------------------------
overbar (such as) y8......................  arithmetic mean
------------------------------------------------------------------------

     (d) Subscripts. This part uses the following subscripts to define 
a quantity:

------------------------------------------------------------------------
               Subscript                             Quantity
------------------------------------------------------------------------
int....................................  speed interval
abs....................................  absolute quantity
act....................................  actual or measured condition
actint.................................  actual or measured condition
                                          over the speed interval
atmos..................................  atmospheric
b......................................  base
c......................................  coastdown
e......................................  effective
error..................................  error
exp....................................  expected quantity
i......................................  an individual of a series
final..................................  final
init...................................  initial quantity, typically
                                          before an emission test
max....................................  the maximum (i.e., peak) value
                                          expected at the standard over
                                          a test interval; not the
                                          maximum of an instrument range
meas...................................  measured quantity
ref....................................  reference quantity
rev....................................  revolution
roll...................................  dynamometer roll
s......................................  settling
sat....................................  saturated condition
si.....................................  speed interval
span...................................  span quantity
test...................................  test quantity
uncor..................................  uncorrected quantity
zero...................................  zero quantity
------------------------------------------------------------------------

     (e) Other acronyms and abbreviations. This part uses the following 
additional abbreviations and acronyms:

------------------------------------------------------------------------
 
------------------------------------------------------------------------
CFR....................................  Code of Federal Regulations
EPA....................................  Environmental Protection Agency
FID....................................  flame-ionization detector
GVWR...................................  gross vehicle weight rating
NIST...................................  National Institute for
                                          Standards and Technology
RESS...................................  rechargeable energy storage
                                          system
SAE....................................  Society of Automotive Engineers
U.S.C..................................  United States Code
------------------------------------------------------------------------

Sec.  1066.710  Reference materials.

    (a) Certain material is incorporated by reference into this part 
with the approval of the Director of the Federal Register under 5 
U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other than that 
specified in this section, the Environmental Protection Agency must 
publish a notice of the change in the Federal Register and the material 
must be available to the public. All approved material is available for 
inspection at U.S. EPA, Air and Radiation Docket and Information 
Center, 1301 Constitution Ave., NW., Room B102, EPA West Building, 
Washington, DC 20460, (202) 202-1744, and is available from the sources 
listed below. It is also available for inspection at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to 
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
    (b) Society of Automotive Engineers, 400 Commonwealth Dr., 
Warrendale, PA 15096-0001, (877) 606-7323 (U.S. and Canada) or (724) 
776-4970 (outside the U.S. and Canada), http://www.sae.org.
    (1) SAE J1263, Road Load Measurement and Dynamometer Simulation 
Using Coastdown Techniques, Revised March 2010, IBR approved for 
Sec. Sec.  1066.301(b) and 1066.310(b).
    (2) SAE J2263, Road Load Measurement Using Onboard

[[Page 57488]]

Anemometry and Coastdown Techniques, Revised December 2008, IBR 
approved for Sec. Sec.  1066.301(b), and 1066.310(b).
    (3) SAE J2711, Recommended Practice for Measuring Fuel Economy and 
Emissions of Hybrid-Electric and Conventional Heavy-Duty Vehicles, 
Issued September 2002, IBR approved for Sec.  1066.501.
    (c) National Institute of Standards and Technology, 100 Bureau 
Drive, Stop 1070, Gaithersburg, MD 20899-1070, (301) 975-6478, http://www.nist.gov, or inquiries@nist.gov.
    (1) NIST Special Publication 811, 2008 Edition, Guide for the Use 
of the International System of Units (SI), March 2008, IBR approved for 
Sec. Sec.  1066.20(a) and 1066.705.
    (2) [Reserved]

PART 1068--GENERAL COMPLIANCE PROVISIONS FOR HIGHWAY, STATIONARY, 
AND NONROAD PROGRAMS

0
94. The authority citation for part 1068 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

0
95. The heading for part 1068 is revised to read as set forth above.

Subpart A--[Amended]

0
96. Section 1068.1 is revised to read as follows:

Sec.  1068.1  Does this part apply to me?

    (a) The provisions of this part apply to everyone with respect to 
the following engines and to equipment using the following engines 
(including owners, operators, parts manufacturers, and persons 
performing maintenance):
    (1) Locomotives we regulate under 40 CFR part 1033.
    (2) Heavy-duty motor vehicles and motor vehicle engines to the 
extent and in the manner specified in 40 CFR parts 85, 86, 1036 and 
1037.
    (3) Land-based nonroad compression-ignition engines we regulate 
under 40 CFR part 1039.
    (4) Stationary compression-ignition engines certified using the 
provisions of 40 CFR part 1039, as indicated in 40 CFR part 60, subpart 
IIII.
    (5) Marine compression-ignition engines we regulate under 40 CFR 
part 1042.
    (6) Marine spark-ignition engines we regulate under 40 CFR part 
1045.
    (7) Large nonroad spark-ignition engines we regulate under 40 CFR 
part 1048.
    (8) Stationary spark-ignition engines certified using the 
provisions of 40 CFR part 1048 or part 1054, as indicated in 40 CFR 
part 60, subpart JJJJ.
    (9) Recreational engines and vehicles we regulate under 40 CFR part 
1051 (such as snowmobiles and off-highway motorcycles).
    (10) Small nonroad spark-ignition engines we regulate under 40 CFR 
part 1054.
    (b) This part does not apply to any of the following engine or 
vehicle categories, except as specified in paragraph (d) of this 
section or as specified in other parts:
    (1) Light-duty motor vehicles (see 40 CFR part 86).
    (2) Highway motorcycles (see 40 CFR part 86).
    (3) Aircraft engines (see 40 CFR part 87).
    (4) Land-based nonroad compression-ignition engines we regulate 
under 40 CFR part 89.
    (5) Small nonroad spark-ignition engines we regulate under 40 CFR 
part 90.
    (c) Paragraph (a) of this section identifies the parts of the CFR 
that define emission standards and other requirements for particular 
types of engines and equipment. This part 1068 refers to each of these 
other parts generically as the ``standard-setting part.'' For example, 
40 CFR part 1051 is always the standard-setting part for snowmobiles. 
Follow the provisions of the standard-setting part if they are 
different than any of the provisions in this part.
    (d) Specific provisions in this part 1068 start to apply separate 
from the schedule for certifying engines to new emission standards, as 
follows:
    (1) The provisions of Sec. Sec.  1068.30 and 1068.310 apply for 
stationary spark-ignition engines built on or after January 1, 2004, 
and for stationary compression-ignition engines built on or after 
January 1, 2006.
    (2) The provisions of Sec. Sec.  1068.30 and 1068.235 apply for the 
types of engines/equipment listed in paragraph (a) of this section 
beginning January 1, 2004, if they are used solely for competition.

Subpart C--[Amended]

0
97. Section 1068.210 is revised to read as follows:

Sec.  1068.210  What are the provisions for exempting test engines/
equipment?

    (a) We may exempt engines/equipment that you will use for research, 
investigations, studies, demonstrations, or training. Note that you are 
not required to get an exemption under this section for engines that 
are exempted under other provisions of this part, such as the 
manufacturer-owned exemption in Sec.  1068.215.
    (b) Anyone may ask for a testing exemption.
    (c) If you are a certificate holder, you may request an exemption 
for engines/equipment you intend to include in test programs over a 
two-year period.
    (1) In your request, tell us the maximum number of engines/
equipment involved and describe how you will make sure exempted 
engines/equipment are used only for this testing. For example, if the 
exemption will involve other companies using your engines/equipment, 
describe your plans to track individual units so you can properly 
report on their final disposition.
    (2) Give us the information described in paragraph (d) of this 
section if we ask for it.
    (d) If you are not a certificate holder, do all the following 
things:
    (1) Show that the proposed test program has a valid purpose under 
paragraph (a) of this section.
    (2) Show you need an exemption to achieve the purpose of the test 
program (time constraints may be a basis for needing an exemption, but 
the cost of certification alone is not).
    (3) Estimate the duration of the proposed test program and the 
number of engines/equipment involved.
    (4) Allow us to monitor the testing.
    (5) Describe how you will ensure that you stay within this 
exemption's purposes. Address at least the following things:
    (i) The technical nature of the test.
    (ii) The test site.
    (iii) The duration and accumulated engine/equipment operation 
associated with the test.
    (iv) Ownership and control of the engines/equipment involved in the 
test.
    (v) The intended final disposition of the engines/equipment.
    (vi) How you will identify, record, and make available the engine/
equipment identification numbers.
    (vii) The means or procedure for recording test results.
    (e) If we approve your request for a testing exemption, we will 
send you a letter or a memorandum describing the basis and scope of the 
exemption. It will also include any necessary terms and conditions, 
which normally require you to do the following:
    (1) Stay within the scope of the exemption.
    (2) Create and maintain adequate records that we may inspect.
    (3) Add a permanent label to all engines/equipment exempted under 
this section, consistent with Sec.  1068.45, with at least the 
following items:

[[Page 57489]]

    (i) The label heading ``EMISSION CONTROL INFORMATION''.
    (ii) Your corporate name and trademark.
    (iii) Engine displacement, family identification, and model year of 
the engine/equipment (as applicable), or whom to contact for further 
information.
    (iv) One of these statements (as applicable):
    (A) ``THIS ENGINE IS EXEMPT UNDER 40 CFR 1068.210 OR 1068.215 FROM 
EMISSION STANDARDS AND RELATED REQUIREMENTS.''
    (B) ``THIS EQUIPMENT IS EXEMPT UNDER 40 CFR 1068.210 OR 1068.215 
FROM EMISSION STANDARDS AND RELATED REQUIREMENTS.''
    (4) Tell us when the test program is finished.
    (5) Tell us the final disposition of the engines/equipment.
    (6) Send us a written confirmation that you meet the terms and 
conditions of this exemption.

0
98. Section 1068.235 is revised to read as follows:

Sec.  1068.235  What are the provisions for exempting engines/equipment 
used solely for competition?

    (a) New engines/equipment you produce that are used solely for 
competition are generally excluded from emission standards. See the 
standard-setting parts for specific provisions where applicable.
    (b) If you modify any nonroad engines/equipment after they have 
been placed into service in the United States so they will be used 
solely for competition, they are exempt without request. This exemption 
applies only to the prohibition in Sec.  1068.101(b)(1) and is valid 
only as long as the engine/equipment is used solely for competition. 
You may not use the provisions of this paragraph (b) to circumvent the 
requirements that apply to the sale of new competition engines under 
the standard-setting part.
    (c) If you modify any nonroad engines/equipment under paragraph (b) 
of this section, you must destroy the original emission labels. If you 
loan, lease, sell, or give any of these engines/equipment to someone 
else, you must tell the new owner (or operator, if applicable) in 
writing that they may be used only for competition.

Subpart D--[Amended]

0
99. Section 1068.325 is revised to read as follows:

Sec.  1068.325  What are the temporary exemptions for imported engines/
equipment?

    You may import engines/equipment under certain temporary 
exemptions, subject to the conditions in this section. We may ask U.S. 
Customs and Border Protection to require a specific bond amount to make 
sure you comply with the requirements of this subpart. You may not sell 
or lease one of these engines/equipment while it is in the United 
States except as specified in this section or Sec.  1068.201(i). You 
must eventually export the engine/equipment as we describe in this 
section unless it conforms to a certificate of conformity or it 
qualifies for one of the permanent exemptions in Sec.  1068.315.
    (a) Exemption for repairs or alterations. You may temporarily 
import nonconforming engines/equipment under bond solely for repair or 
alteration, subject to our advance approval as described in paragraph 
(j) of this section. You may operate the engine/equipment in the United 
States only as necessary to repair it, alter it, or ship it to or from 
the service location. Export the engine/equipment directly after 
servicing is complete.
    (b) Testing exemption. You may temporarily import nonconforming 
engines/equipment under bond for testing if you follow the requirements 
of Sec.  1068.210, subject to our advance approval as described in 
paragraph (j) of this section. You may operate the engines/equipment in 
the United States only as needed to perform tests. This exemption 
expires one year after you import the engine/equipment unless we 
approve an extension. The engine/equipment must be exported before the 
exemption expires. You may sell or lease the engines/equipment 
consistent with the provisions of Sec.  1068.210.
    (c) Display exemption. You may temporarily import nonconforming 
engines/equipment under bond for display if you follow the requirements 
of Sec.  1068.220, subject to our advance approval as described in 
paragraph (j) of this section. This exemption expires one year after 
you import the engine/equipment, unless we approve your request for an 
extension. We may approve an extension of up to one more year for each 
request, but no more than three years total. The engine/equipment must 
be exported by the time the exemption expires or directly after the 
display concludes, whichever comes first.
    (d) Export exemption. You may temporarily import nonconforming 
engines/equipment to export them, as described in Sec.  1068.230. You 
may operate the engine/equipment in the United States only as needed to 
prepare it for export. Label the engine/equipment as described in Sec.  
1068.230. You may sell or lease the engines/equipment for operation 
outside the United States consistent with the provisions of Sec.  
1068.230.
    (e) Diplomatic or military exemption. You may temporarily import 
nonconforming engines/equipment without bond if you represent a foreign 
government in a diplomatic or military capacity. In your request to the 
Designated Compliance Officer (see Sec.  1068.305), include either 
written confirmation from the U.S. State Department that you qualify 
for this exemption or a copy of your orders for military duty in the 
United States. We will rely on the State Department or your military 
orders to determine when your diplomatic or military status expires, at 
which time you must export your exempt engines/equipment.
    (f) Delegated-assembly exemption. You may import a nonconforming 
engine for final assembly under the provisions of Sec.  1068.261. You 
may sell or lease the engines/equipment consistent with the provisions 
of Sec.  1068.261.
    (g) Exemption for partially complete engines. You may import an 
engine if another company already has a certificate of conformity and 
will be modifying the engine to be in its final certified configuration 
or a final exempt configuration under the provisions of Sec.  1068.262. 
You may also import a partially complete engine by shipping it from one 
of your facilities to another under the provisions of Sec.  
1068.260(c). If you are importing a used engine that becomes new as a 
result of importation, you must meet all the requirements that apply to 
original engine manufacturers under Sec.  1068.262. You may sell or 
lease the engines consistent with the provisions of Sec.  1068.262.
    (h) [Reserved]
    (i) [Reserved]
    (j) Approvals. For the exemptions in this section requiring our 
approval, you must send a request to the Designated Compliance Officer 
before importing the engines/equipment. We will approve your request if 
you meet all the applicable requirements and conditions. If another 
section separately requires that you request approval for the 
exemption, you may combine the information requirements in a single 
request. Include the following information in your request:
    (1) Identify the importer of the engine/equipment and the 
applicable postal address, e-mail address, and telephone number.

[[Page 57490]]

    (2) Identify the engine/equipment owner and the applicable postal 
address, e-mail address, and telephone number.
    (3) Identify the engine/equipment by model number (or name), serial 
number, and original production year.
    (4) Identify the specific regulatory provision under which you are 
seeking an exemption.
    (5) Authorize EPA enforcement officers to conduct inspections or 
testing as allowed under the Clean Air Act.
    (6) Include any additional information we specify for demonstrating 
that you qualify for the exemption.

Department of Transportation

National Highway Traffic Safety Administration

49 CFR Chapter V

    In consideration of the foregoing, under the authority of 49 U.S.C. 
32901 and 32902 and delegation of authority at 49 CFR 1.50, NHTSA 
amends 49 CFR chapter V as follows:

PART 523--VEHICLE CLASSIFICATION

0
100. The authority citation for part 523 continues to read as follows:

    Authority: 49 U.S.C. 32901; delegation of authority at 49 CFR 
1.50.

0
101. Revise Sec.  523.2 to read as follows:

Sec.  523.2  Definitions.

    As used in this part:
    Approach angle means the smallest angle, in a plane side view of an 
automobile, formed by the level surface on which the automobile is 
standing and a line tangent to the front tire static loaded radius arc 
and touching the underside of the automobile forward of the front tire.
    Axle clearance means the vertical distance from the level surface 
on which an automobile is standing to the lowest point on the axle 
differential of the automobile.
    Base tire means the tire specified as standard equipment by a 
manufacturer on each subconfiguration of a model type.
    Basic vehicle frontal area is used as defined in 40 CFR 86.1803.
    Breakover angle means the supplement of the largest angle, in the 
plan side view of an automobile that can be formed by two lines tangent 
to the front and rear static loaded radii arcs and intersecting at a 
point on the underside of the automobile.
    Cab-complete vehicle means a vehicle that is first sold as an 
incomplete vehicle that substantially includes the vehicle cab section 
as defined in 40 CFR 1037.801. For example, vehicles known commercially 
as chassis-cabs, cab-chassis, box-deletes, bed-deletes, cut-away vans 
are considered cab-complete vehicles. A cab includes a steering column 
and passenger compartment. Note a vehicle lacking some components of 
the cab is a cab-complete vehicle if it substantially includes the cab.
    Cargo-carrying volume means the luggage capacity or cargo volume 
index, as appropriate, and as those terms are defined in 40 CFR 
600.315, in the case of automobiles to which either of those terms 
apply. With respect to automobiles to which neither of those terms 
apply ``cargo-carrying volume'' means the total volume in cubic feet 
rounded to the nearest 0.1 cubic feet of either an automobile's 
enclosed nonseating space that is intended primarily for carrying cargo 
and is not accessible from the passenger compartment, or the space 
intended primarily for carrying cargo bounded in the front by a 
vertical plane that is perpendicular to the longitudinal centerline of 
the automobile and passes through the rearmost point on the rearmost 
seat and elsewhere by the automobile's interior surfaces.
    Class 2b vehicles are vehicles with a gross vehicle weight rating 
(GVWR) ranging from 8,501 to 10,000 pounds.
    Class 3 through Class 8 vehicles are vehicles with a gross vehicle 
weight rating (GVWR) of 10,001 pounds or more as defined in 49 CFR 
565.15.
    Commercial medium- and heavy-duty on-highway vehicle means an on-
highway vehicle with a gross vehicle weight rating of 10,000 pounds or 
more as defined in 49 U.S.C. 32901(a)(7).
    Complete vehicle means a vehicle that requires no further 
manufacturing operations to perform its intended function and is a 
functioning vehicle that has the primary load carrying device or 
container (or equivalent equipment) attached or that is designed to 
pull a trailer. Examples of equivalent equipment would include fifth 
wheel trailer hitches, firefighting equipment, and utility booms.
    Curb weight is defined the same as vehicle curb weight in 40 CFR 
86.1803-01.
    Departure angle means the smallest angle, in a plane side view of 
an automobile, formed by the level surface on which the automobile is 
standing and a line tangent to the rear tire static loaded radius arc 
and touching the underside of the automobile rearward of the rear tire.
    Final stage manufacturer has the meaning given in 49 CFR 567.3.
    Footprint is defined as the product of track width (measured in 
inches, calculated as the average of front and rear track widths, and 
rounded to the nearest tenth of an inch) times wheelbase (measured in 
inches and rounded to the nearest tenth of an inch), divided by 144 and 
then rounded to the nearest tenth of a square foot. For purposes of 
this definition, track width is the lateral distance between the 
centerlines of the base tires at ground, including the camber angle. 
For purposes of this definition, wheelbase is the longitudinal distance 
between front and rear wheel centerlines.
    Gross combination weight rating or GCWR means the value specified 
by the manufacturer as the maximum allowable loaded weight of a 
combination vehicle (e.g. tractor plus trailer).
    Gross vehicle weight rating or GVWR means the value specified by 
the vehicle manufacturer as the maximum design loaded weight of a 
single vehicle (e.g. vocational vehicle).
    Heavy-duty engine means any engine used for (or for which the 
engine manufacturer could reasonably expect to be used for) motive 
power in a heavy-duty vehicle. For purposes of this definition in this 
part, the term ``engine'' includes internal combustion engines and 
other devices that convert chemical fuel into motive power. For 
example, a fuel cell and motor used in a heavy-duty vehicle is a heavy-
duty engine.
    Heavy-duty off-road vehicle means a heavy-duty vocational vehicle 
or vocational tractor that is intended for off-road use meeting either 
of the following criteria:
    (1) Vehicles with tires installed having a maximum speed rating at 
or below 55 mph.
    (2) Vehicles primarily designed to perform work off-road (such as 
in oil fields, forests, or construction sites), and meeting at least 
one of the criteria of paragraph (2)(i) of this definition and at least 
one of the criteria of paragraph (2)(ii) of this definition.
    (i) Vehicle must have affixed components designed to work in an 
off-road environment (for example, hazardous material equipment or 
drilling equipment) or was designed to operate at low speeds making 
them unsuitable for normal highway operation.
    (ii) Vehicles must:
    (A) Have an axle that has a gross axle weight rating (GAWR) of 
29,000 pounds or more;
    (B) Have a speed attainable in 2 miles of not more than 33 mph; or
    (C) Have a speed attainable in 2 miles of not more than 45 mph, an 
unloaded vehicle weight that is not less than 95

[[Page 57491]]

percent of its gross vehicle weight rating (GVWR), and no capacity to 
carry occupants other than the driver and operating crew.
    Heavy-duty vehicle means a vehicle as defined in Sec.  523.6.
    Incomplete vehicle means a vehicle which does not have the primary 
load carrying device or container attached when it is first sold as a 
vehicle or any vehicle that does not meet the definition of a complete 
vehicle. This may include vehicles sold to secondary vehicle 
manufacturers. Incomplete vehicles include cab-complete vehicles.
    Innovative technology means technology certified under 40 CFR 
1037.610.
    Light truck means a non-passenger automobile meeting the criteria 
in Sec.  523.5.
    Medium duty passenger vehicle means a vehicle which would satisfy 
the criteria in Sec.  523.5 (relating to light trucks) but for its 
gross vehicle weight rating or its curb weight, which is rated at more 
than 8,500 lbs GVWR or has a vehicle curb weight of more than 6,000 
pounds or has a basic vehicle frontal area in excess of 45 square feet, 
and which is designed primarily to transport passengers, but does not 
include a vehicle that:
    (1) Is an ``incomplete vehicle''' as defined in this subpart; or
    (2) Has a seating capacity of more than 12 persons; or
    (3) Is designed for more than 9 persons in seating rearward of the 
driver's seat; or
    (4) Is equipped with an open cargo area (for example, a pick-up 
truck box or bed) of 72.0 inches in interior length or more. A covered 
box not readily accessible from the passenger compartment will be 
considered an open cargo area for purposes of this definition.
    Motor home has the meaning given in 49 CFR 571.3.
    Motor vehicle has the meaning given in 40 CFR 85.1703.
    Passenger-carrying volume means the sum of the front seat volume 
and, if any, rear seat volume, as defined in 40 CFR 600.315, in the 
case of automobiles to which that term applies. With respect to 
automobiles to which that term does not apply, ``passenger-carrying 
volume'' means the sum in cubic feet, rounded to the nearest 0.1 cubic 
feet, of the volume of a vehicle's front seat and seats to the rear of 
the front seat, as applicable, calculated as follows with the head 
room, shoulder room, and leg room dimensions determined in accordance 
with the procedures outlined in Society of Automotive Engineers 
Recommended Practice J1100a, Motor Vehicle Dimensions (Report of Human 
Factors Engineering Committee, Society of Automotive Engineers, 
approved September 1973 and last revised September 1975).
    (1) For front seat volume, divide 1,728 into the product of the 
following SAE dimensions, measured in inches to the nearest 0.1 inches, 
and round the quotient to the nearest 0.001 cubic feet.
    (i) H61-Effective head room--front.
    (ii) W3-Shoulder room--front.
    (iii) L34-Maximum effective leg room-accelerator.
    (2) For the volume of seats to the rear of the front seat, divide 
1,728 into the product of the following SAE dimensions, measured in 
inches to the nearest 0.1 inches, and rounded the quotient to the 
nearest 0.001 cubic feet.
    (i) H63-Effective head room--second.
    (ii) W4-Shoulder room--second.
    (iii) L51-Minimum effective leg room--second.
    Pickup truck means a non-passenger automobile which has a passenger 
compartment and an open cargo area (bed).
    Recreational vehicle or RV means a motor vehicle equipped with 
living space and amenities found in a motor home.
    Running clearance means the distance from the surface on which an 
automobile is standing to the lowest point on the automobile, excluding 
unsprung weight.
    Static loaded radius arc means a portion of a circle whose center 
is the center of a standard tire-rim combination of an automobile and 
whose radius is the distance from that center to the level surface on 
which the automobile is standing, measured with the automobile at curb 
weight, the wheel parallel to the vehicle's longitudinal centerline, 
and the tire inflated to the manufacturer's recommended pressure.
    Temporary living quarters means a space in the interior of an 
automobile in which people may temporarily live and which includes 
sleeping surfaces, such as beds, and household conveniences, such as a 
sink, stove, refrigerator, or toilet.
    Van means a vehicle with a body that fully encloses the driver and 
a cargo carrying or work performing compartment. The distance from the 
leading edge of the windshield to the foremost body section of vans is 
typically shorter than that of pickup trucks and sport utility 
vehicles.
    Vocational tractor means a tractor that is classified as a 
vocational vehicle according to 40 CFR 1037.630.
    Vocational vehicle means a vehicle that is equipped for a 
particular industry, trade or occupation such as construction, heavy 
hauling, mining, logging, oil fields, refuse and includes vehicles such 
as school buses, motorcoaches and RVs.
    Work truck means a vehicle that is rated at more than 8,500 pounds 
and less than or equal to 10,000 pounds gross vehicle weight, and is 
not a medium-duty passenger vehicle as defined in 40 CFR 86.1803 
effective as of December 20, 2007.

0
102. Add a new Sec.  523.6 to read as follows:

Sec.  523.6  Heavy-duty vehicle.

    (a) A heavy-duty vehicle is any commercial medium- and heavy-duty 
on highway vehicle or a work truck, as defined in 49 U.S.C. 32901(a)(7) 
and (19). For the purpose of this part, heavy-duty vehicles are divided 
into three regulatory categories as follows:
    (1) Heavy-duty pickup trucks and vans;
    (2) Heavy-duty vocational vehicles; and
    (3) Truck tractors with a GVWR above 26,000 pounds.
    (b) The heavy-duty vehicle classification does not include:
    (1) Vehicles defined as medium duty passenger vehicles.
    (2) Vehicles excluded from the definition of ``heavy-duty vehicle'' 
because of vehicle weight or weight rating (such as light duty vehicles 
as defined in Sec.  523.5).
    (3) Vehicles excluded from the definition of motor vehicle in 40 
CFR 85.1703.

0
103. Add a new Sec.  523.7 to read as follows:

Sec.  523.7  Heavy-duty pickup trucks and vans.

    Heavy-duty pickup trucks and vans are pickup trucks and vans with a 
gross vehicle weight rating between 8,501 pounds and 14,000 pounds 
(Class 2b through 3 vehicles) manufactured as complete vehicles by a 
single or final stage manufacturer or manufactured as incomplete 
vehicles as designated by a manufacturer. A manufacturer may also 
optionally designate incomplete or complete Class 4 or 5 vehicles as 
heavy-duty pickup trucks or vans or spark-ignition (or gasoline) 
engines certified and sold as loose engines manufactured for use in 
heavy-duty pickup trucks or vans. See references in 40 CFR 1037.104 and 
40 CFR 1037.150.

0
104. Add a new Sec.  523.8 to read as follows:

Sec.  523.8  Heavy-duty vocational vehicle.

    Heavy-duty vocational vehicles are vehicles with a gross vehicle 
weight

[[Page 57492]]

rating (GVWR) above 8,500 pounds excluding:
    (a) Heavy-duty pickup trucks and vans defined in Sec.  523.7;
    (b) Medium duty passenger vehicles; and
    (c) Truck tractors, except vocational tractors, with a GVWR above 
26,000 pounds;

0
105. Add a new Sec.  523.9 to read as follows:

Sec.  523.9  Truck tractors.

    Truck tractors for the purpose of this part are considered as any 
truck tractor as defined in 49 CFR part 571 having a GVWR above 26,000 
pounds.

PART 534--RIGHTS AND RESPONSIBILITIES OF MANUFACTURERS IN THE 
CONTEXT OF CHANGES IN CORPORATE RELATIONSHIPS

0
106. The authority citation for part 534 continues to read as follows:

    Authority: 49 U.S.C. 32901; delegation of authority at 49 CFR 
1.50.

0
107. Revise Sec.  534.1 to read as follows:

Sec.  534.1  Scope.

    This part defines the rights and responsibilities of manufacturers 
in the context of changes in corporate relationships for purposes of 
the fuel economy and fuel consumption programs established by 49 U.S.C. 
chapter 329.

0
108. Revise Sec.  534.2 to read as follows:

Sec.  534.2  Applicability.

    This part applies to manufacturers of passenger automobiles, light 
trucks, heavy-duty vehicles and the engines manufactured for use in 
heavy-duty vehicles as defined in 49 CFR part 523.

0
109. Revise Sec.  534.4 to read as follows.

Sec.  534.4  Successors and predecessors.

    For purposes of the fuel economy and fuel consumption programs, 
``manufacturer'' includes ``predecessors'' and ``successors'' to the 
extent specified in this section.
    (a) Successors are responsible for any civil penalties that arise 
out of fuel economy and fuel consumption shortfalls incurred and not 
satisfied by predecessors.
    (b) If one manufacturer has become the successor of another 
manufacturer during a model year, all of the vehicles or engines 
produced by those manufacturers during the model year are treated as 
though they were manufactured by the same manufacturer. A manufacturer 
is considered to have become the successor of another manufacturer 
during a model year if it is the successor on September 30 of the 
corresponding calendar year and was not the successor for the preceding 
model year.
    (c)(1) For passenger automobiles and light trucks, fuel economy 
credits earned by a predecessor before or during model year 2007 may be 
used by a successor, subject to the availability of credits and the 
general three-year restriction on carrying credits forward and the 
general three-year restriction on carrying credits backward. Fuel 
economy credits earned by a predecessor after model year 2007 may be 
used by a successor, subject to the availability of credits and the 
general five-year restriction on carrying credits forward and the 
general three-year restriction on carrying credits backward.
    (2) For heavy-duty vehicles and heavy-duty vehicle engines, 
available fuel consumption credits earned by a predecessor after model 
year 2015, and in model years 2013, 2014 and 2015 if a manufacturer 
voluntarily complies in those model years, may be used by a successor, 
subject to the availability of credits and the general five-year 
restriction on carrying credits forward and the general three year 
restriction on carrying credits backward.
    (d)(1) For passenger automobiles and light trucks, fuel economy 
credits earned by a successor before or during model year 2007 may be 
used to offset a predecessor's shortfall, subject to the availability 
of credits and the general three-year restriction on carrying credits 
forward and the general three-year restriction on carrying credits 
backward. Credits earned by a successor after model year 2007 may be 
used to offset a predecessor's shortfall, subject to the availability 
of credits and the general five-year restriction on carrying credits 
forward and the general three-year restriction on carrying credits 
backward.
    (2) For heavy-duty vehicles and heavy-duty vehicle engines, 
available credits earned by a successor after model year 2015, and in 
model years 2013, 2014 and 2015, if a manufacturer voluntarily complies 
in those model years, may be used by a predecessor subject to the 
availability of credits and the general five-year restriction on 
carrying credits forward and the general three year restriction on 
carrying credits backward.

0
110. Amend Sec.  534.5 by revising paragraphs (a), (c), and (d) to read 
as follows:

Sec.  534.5  Manufacturers within control relationships.

    (a) If a civil penalty arises out of a fuel economy or fuel 
consumption shortfall incurred by a group of manufacturers within a 
control relationship, each manufacturer within that group is jointly 
and severally liable for the civil penalty.
* * * * *
    (c)(1) For passenger automobiles and light trucks, fuel economy 
credits of a manufacturer within a control relationship may be used by 
the group of manufacturers within the control relationship to offset 
shortfalls, subject to the agreement of the other manufacturers, the 
availability of the credits, and the general three year restriction on 
carrying credits forward or backward prior to or during model year 
2007, or the general five year restriction on carrying credits forward 
and the general three-year restriction on carrying credits backward 
after model year 2007.
    (2) For heavy-duty vehicles and heavy-duty engines, credits of a 
manufacturer within a control relationship may be used by the group of 
manufacturers within the control relationship to offset shortfalls, 
subject to the agreement of the other manufacturers, the availability 
of the credits, the general 5-year restriction on carrying credits 
forward, and the general three year restriction on offsetting past 
credit shortfalls as specified in the requirements of 49 CFR 535.7.
    (d)(1) For passenger automobiles and light trucks, if a 
manufacturer within a group of manufacturers is sold or otherwise spun 
off so that it is no longer within that control relationship, the 
manufacturer may use credits that were earned by the group of 
manufacturers within the control relationship while the manufacturer 
was within that relationship, subject to the agreement of the other 
manufacturers, the availability of the credits, and the general three-
year restriction on carrying credits forward or backward prior to or 
during model year 2007, or the general five-year restriction on 
carrying credits forward and the general three-year restriction on 
carrying credits backward after model year 2007.
    (2) For heavy-duty vehicles and heavy-duty vehicle engines, if a 
manufacturer within a group of manufacturers is sold or otherwise spun 
off so that it is no longer within that control relationship, the 
manufacturer may use credits that were earned by the group of 
manufacturers within the control relationship while the manufacturer 
was within that relationship, subject to the agreement of the other 
manufacturers, the availability of the credits, the general 5-year 
restriction on carrying credits forward,

[[Page 57493]]

and the general three year restriction on offsetting past credit 
shortfalls as specified in the requirements of 49 CFR 535.7.
* * * * *

0
111. Revise Sec.  534.6 to read as follows.

Sec.  534.6  Reporting corporate transactions.

    Manufacturers who have entered into written contracts transferring 
rights and responsibilities such that a different manufacturer owns the 
controlling stock or exerts control over the design, production or sale 
of automobiles or heavy-duty vehicles to which Corporate Average Fuel 
Economy or Fuel Consumption standards apply shall report the contract 
to the agency as follows:
    (a) The manufacturers must file a certified report with the agency 
affirmatively stating that the contract transfers rights and 
responsibilities between them such that one manufacturer has assumed a 
controlling stock ownership or control over the design, production or 
sale of vehicles. The report must also specify the first full model 
year to which the transaction will apply.
    (b) Each report shall--
    (1) Identify each manufacturer;
    (2) State the full name, title, and address of the official 
responsible for preparing the report;
    (3) Identify the production year being reported on;
    (4) Be written in the English language; and
    (5) Be submitted to: Administrator, National Highway Traffic Safety 
Administration, 1200 New Jersey Avenue, SE., Washington, DC 20590.
    (c) The manufacturers may seek confidential treatment for 
information provided in the certified report in accordance with 49 CFR 
part 512.

0
112. A new part 535 is added to chapter V to read as follows:

PART 535 MEDIUM- AND HEAVY-DUTY VEHICLE FUEL EFFICIENCY PROGRAM

Sec.
535.1 Scope.
535.2 Purpose.
535.3 Applicability.
535.4 Definitions.
535.5 Standards.
535.6 Measurement and calculation procedures.
535.7 Averaging, banking, and trading (ABT) program.
535.8 Reporting requirements.
535.9 Enforcement approach.

    Authority: 49 U.S.C. 32902; delegation of authority at 49 CFR 
1.50.

Sec.  535.1  Scope.

    This part establishes fuel consumption standards pursuant to 49 
U.S.C. 32902(k) for work trucks and commercial medium-duty and heavy-
duty on-highway vehicles (hereafter referenced as heavy-duty vehicles) 
and engines manufactured for sale in the United States and establishes 
a credit program manufacturers may use to comply with standards and 
requirements for manufacturers to provide reports to the National 
Highway Traffic Safety Administration regarding their efforts to reduce 
the fuel consumption of these vehicles.

Sec.  535.2  Purpose.

    The purpose of this part is to reduce the fuel consumption of new 
heavy-duty vehicles by establishing maximum levels for fuel consumption 
standards while providing a flexible credit program to assist 
manufacturers in complying with standards.

Sec.  535.3  Applicability.

    (a) This part applies to complete vehicle and chassis manufacturers 
of all new heavy-duty vehicles, as defined in 49 CFR part 523, and to 
the manufacturers of all heavy-duty engines manufactured for use in the 
applicable vehicles for each given model year.
    (b) Complete vehicle manufacturers, for the purpose of this part, 
include manufacturers that produce heavy-duty pickup trucks and vans or 
truck tractors as complete vehicles and that hold the EPA certificate 
of conformity.
    (c) Chassis manufacturers, for the purpose of this part, include 
manufacturers that produce incomplete vehicles constructed for use as 
heavy-duty pickup trucks or vans or heavy-duty vocational vehicles and 
that hold the EPA certificate of conformity. Some vocational vehicle 
manufacturers are both chassis and complete vehicle manufacturers. 
These manufacturers will be regulated as chassis manufacturers under 
this program.
    (d) Engine manufacturer, for the purpose of this part, means a 
manufacturer that manufactures engines for heavy-duty vehicles and 
holds the EPA certificate of conformity.
    (e) The heavy-duty vehicles, chassis and engines excluded from the 
requirements of this part include:
    (1) Recreational vehicles, including motor homes.
    (2) Vehicles and engines exempted by EPA in accordance with 40 CFR 
parts 1036 and 1037.
    (f) Vehicles and engines produced by small business manufacturers 
as defined by the Small Business Administration at 13 CFR 121.201 are 
exempted as specified in Sec.  535.8(h).
    (g) Heavy-duty off-road vehicles meeting the criteria in 49 CFR 
part 523 are exempt without request from vehicle standards of Sec.  
535.5(b). Manufacturers of vehicles not meeting the criteria for the 
heavy-duty off-road vehicle exclusion may submit a petition as 
specified in Sec.  535.8(h) to EPA and NHTSA for an exclusion from the 
vehicle standards of Sec.  535.5(b).
    (h) A vehicle manufacturer that completes assembly of a vehicle at 
two or more facilities may ask to use as the date of manufacture for 
that vehicle the date on which manufacturing is completed at the place 
of main assembly, consistent with provisions of 49 CFR 567.4, as the 
model year. Note that such staged assembly is subject to the provisions 
of 40 CFR 1068.260(c). NHTSA's allowance of this provision is effective 
when EPA approves the manufacturer's certificates of conformity for 
these vehicles.

Sec.  535.4  Definitions.

    The terms manufacture and manufacturer are used as defined in 
section 501 of the Act and the terms commercial medium-duty and heavy-
duty on highway vehicle, fuel and work truck are used as defined in 49 
U.S.C. 32901.
    A to B testing means testing performed in pairs to allow comparison 
of vehicle A to vehicle B.
    Act means the Motor Vehicle Information and Cost Savings Act, as 
amended by Pub. L. 94-163 and 96-425.
    Administrator means the Administrator of the National Highway 
Traffic Safety Administration (NHTSA) or the Administrator's delegate.
    Advanced technology means vehicle technology certified under 40 CFR 
1036.615 and 1037.615.
    Averaging set means, a set of engines or vehicles in which fuel 
consumption credits may be exchanged. Credits generated by one engine 
or vehicle family may only be used by other respective engine or 
vehicle families in the same averaging set. Note that an averaging set 
may comprise more than one regulatory subcategory. The averaging sets 
for this HD program are defined as follows:
    (1) Heavy-duty pickup trucks and vans.
    (2) Vocational light-heavy vehicles at or below 19,500 pounds GVWR.
    (3) Vocational and tractor medium-heavy vehicles above 19,500 
pounds GVWR but at or below 33,000 pounds GVWR.

[[Page 57494]]

    (4) Vocational and tractor heavy-heavy vehicles above 33,000 pounds 
GVWR.
    (5) Compression-ignition light heavy-duty engines for Class 2b to 5 
vehicles with a GVWR above 8,500 pounds but at or below 19,500 pounds.
    (6) Compression-ignition medium heavy-duty engines for Class 6 and 
7 vehicles with a GVWR above 19,500 but at or below 33,000 pounds.
    (7) Compression-ignition heavy heavy-duty engines for Class 8 
vehicles with a GVWR above 33,000 pounds.
    (8) Spark-ignition engines in Class 2b to 8 vehicles with a GVWR 
above 8,500 pounds.
    Cab-complete vehicle has the meaning given in 49 CFR part 523.
    Carryover means relating to certification based on emission data 
generated from an earlier model year.
    Certificate holder means the manufacturer who holds the certificate 
of conformity for the vehicle or engine and that assigns the model year 
based on the date when its manufacturing operations are completed 
relative to its annual model year period.
    Certificate of Conformity means an approval document granted by the 
EPA to a manufacturer that submits an application for a vehicle or 
engine emissions family in 40 CFR 1036.205 and 1037.205. A certificate 
of conformity is valid from the indicated effective date until December 
31 of the model year for which it is issued. The certificate must be 
renewed annually for any vehicle a manufacturer continues to produce.
    Certification means process of obtaining a certificate of 
conformity for a vehicle family that complies with the emission 
standards and requirements in this part.
    Certified emission level means the highest deteriorated emission 
level in an engine family for a given pollutant from the applicable 
transient and/or steady-state testing rounded to the same number of 
decimal places as the applicable standard. Note that you may have two 
certified emission levels for CO2 if you certify a family 
for both vocational and tractor use.
    Chassis-cab means the incomplete part of a vehicle that includes a 
frame, a completed occupant compartment and that requires only the 
addition of cargo-carrying, work-performing, or load-bearing components 
to perform its intended functions.
    Chief Counsel means the NHTSA Chief Counsel, or his or her 
designee.
    Complete sister vehicle is a complete vehicle of the same 
configuration as a cab-complete vehicle.
    Complete vehicle has the meaning given in 49 CFR part 523.
    Compression-ignition means relating to a type of reciprocating, 
internal-combustion engine, such as a diesel engine, that is not a 
spark-ignition engine.
    Configuration means a subclassification within a test group which 
is based on engine code, transmission type and gear ratios, final drive 
ratio, and other parameters which the EPA designates.
    Credits (or fuel consumption credits) in this part means an earned 
allowance recognizing the fuel consumption of a particular 
manufacturer's vehicles or engines within a particular averaging set 
exceeds (credit surplus or positive credits) or falls below (credit 
shortfall, deficit or negative credits) that manufacturer's fuel 
consumption standard(s) for the regulatory subcategory(s) that make-up 
the averaging set for a given model year, or purchased allowance. The 
value of an earned credit is calculated according to Sec.  535.7.
    Curb weight has the meaning given in 40 CFR 86.1803.
    Date of manufacture means the date on which the certifying vehicle 
manufacturer completes its manufacturing operations, except as follows:
    (1) Where the certificate holder is an engine manufacturer that 
does not manufacture the chassis, the date of manufacture of the 
vehicle is based on the date assembly of the vehicle is completed.
    (2) EPA and NHTSA may approve an alternate date of manufacture 
based on the date on which the certifying (or primary) vehicle 
manufacturer completes assembly at the place of main assembly, 
consistent with the provisions of 40 CFR 1037.601 and 49 CFR 567.4.
    Day cab means a type of truck tractor cab that is not a ``sleeper 
cab'', as defined in this section.
    Dedicated vehicle has the same meaning as dedicated automobile as 
defined in 49 U.S.C. 32901(a)(8). A dedicated automobile means an 
automobile that operates only on alternative fuels like E85 or natural 
gas, etc.
    Dual fueled (multi-fuel or flexible-fuel vehicle) has the same 
meaning as dual fueled automobile as defined in 49 U.S.C. 32901(a)(9). 
For example, a vehicle that operates on gasoline and E85 or a plug-in 
hybrid electric vehicle is considered a dual fueled vehicle.
    Electric vehicle means a vehicle that does not include an engine, 
and is powered solely by an external source of electricity and/or solar 
power. Note that this does not include electric hybrid or fuel-cell 
vehicles that use a chemical fuel such as gasoline, diesel fuel, or 
hydrogen. Electric vehicles may also be referred to as all-electric 
vehicles to distinguish them from hybrid vehicles.
    Engine family has the meaning given in 40 CFR 1036.230.
    Family certification level (FCL) means the family certification 
limit for an engine family as defined in 40 CFR 1036.801.
    Family emission limit (FEL) means the family emission limit for a 
vehicle family as defined in 40 CFR 1037.801.
    Final-stage manufacturer has the meaning given in 49 CFR 567.3.
    Fleet in this part means all the heavy-duty vehicles or engines 
within each of the regulatory sub-categories that are manufactured by a 
manufacturer in a particular model year and that are subject to fuel 
consumption standards under Sec.  535.5.
    Fleet average fuel consumption is the calculated average fuel 
consumption performance value for a manufacturer's fleet derived from 
the production weighted fuel consumption values of the unique vehicle 
configurations within each vehicle model type that makes up that 
manufacturer's vehicle fleet in a given model year. In this part, the 
fleet average fuel consumption value is determined for each 
manufacturer's fleet of heavy-duty pickup trucks and vans.
    Fleet average fuel consumption standard is the actual average fuel 
consumption standard for a manufacturer's fleet derived from the 
production weighted fuel consumption standards of each unique vehicle 
configuration, based on payload, tow capacity and drive configuration 
(2, 4 or all-wheel drive), of the model types that makes up that 
manufacturer's vehicle fleet in a given model year. In this part, the 
fleet average fuel consumption standard is determined for each 
manufacturer's fleet of heavy-duty pickup trucks and vans.
    Fuel cell means an electrochemical cell that produces electricity 
via the non-combustion reaction of a consumable fuel, typically 
hydrogen.
    Fuel cell electric vehicle means a motor vehicle propelled solely 
by an electric motor where energy for the motor is supplied by a fuel 
cell.
    Fuel efficiency means the amount of work performed for each gallon 
of fuel consumed.
    Good engineering judgment has the meaning given in 40 CFR 1068.30. 
See 40 CFR 1068.5 for the administrative process used to evaluate good 
engineering judgment.

[[Page 57495]]

    Gross combination weight rating (GCWR) has the meaning given in 49 
CFR part 523.
    Gross vehicle weight rating (GVWR) has the meaning given in 49 CFR 
part 523.
    Heavy-duty vehicle has the meaning given in 49 CFR part 523.
    Hybrid engine or hybrid powertrain means an engine or powertrain 
that includes energy storage features other than a conventional battery 
system or conventional flywheel. Supplemental electrical batteries and 
hydraulic accumulators are examples of hybrid energy storage systems. 
Note that certain provisions in this part treat hybrid engines and 
powertrains intended for vehicles that include regenerative braking 
different than those intended for vehicles that do not include 
regenerative braking.
    Hybrid vehicle means a vehicle that includes energy storage 
features (other than a conventional battery system or conventional 
flywheel) in addition to an internal combustion engine or other engine 
using consumable chemical fuel. Supplemental electrical batteries and 
hydraulic accumulators are examples of hybrid energy storage systems. 
Note that certain provisions in this part treat hybrid vehicles that 
include regenerative braking different than those that do not include 
regenerative braking.
    Incomplete vehicle has the meaning given in 49 CFR part 523. For 
the purpose of this regulation, a manufacturer may request EPA and 
NHTSA to allow the certification of a vehicle as an incomplete vehicle 
if it manufactures the engine and sells the unassembled chassis 
components, provided it does not produce and sell the body components 
necessary to complete the vehicle.
    Innovative technology means technology certified under 40 CFR 
1037.610.
    Liquefied petroleum gas (LPG) has the meaning given in 40 CFR 
1036.801.
    Low rolling resistance tire means a tire on a vocational vehicle 
with a tire rolling resistance level (TRRL) of 7.7 kg/metric ton or 
lower, a steer tire on a tractor with a TRRL of 7.7 kg/metric ton or 
lower, or a drive tire on a tractor with a TRRL of 8.1 kg/metric ton or 
lower.
    Model type has the meaning given in 40 CFR 600.002.
    Model year as it applies to engines means the manufacturer's annual 
new model production period, except as restricted under this 
definition. It must include January 1 of the calendar year for which 
the model year is named, may not begin before January 2 of the previous 
calendar year, and it must end by December 31 of the named calendar 
year. Manufacturers may not adjust model years to circumvent or delay 
compliance with standards.
    Model year as it applies to vehicles means the manufacturer's 
annual new model production period, except as restricted under this 
definition and 40 CFR part 85, subpart X. It must include January 1 of 
the calendar year for which the model year is named, may not begin 
before January 2 of the previous calendar year, and it must end by 
December 31 of the named calendar year.
    (1) The manufacturer who holds the certificate of conformity for 
the vehicle must assign the model year based on the date when its 
manufacturing operations are completed relative to its annual model 
year period.
    (2) Unless a vehicle is being shipped to a secondary manufacturer 
that will hold the certificate of conformity, the model year must be 
assigned prior to introduction of the vehicle into U.S. commerce. The 
certifying manufacturer must redesignate the model year if it does not 
complete its manufacturing operations within the originally identified 
model year. A vehicle introduced into U.S. commerce without a model 
year is deemed to have a model year equal to the calendar year of its 
introduction into U.S. commerce unless the certifying manufacturer 
assigns a later date.
    Natural gas has the meaning given in 40 CFR 1036.801. Vehicles that 
use a pilot-ignited natural gas engine (which uses a small diesel fuel 
ignition system), are still considered natural gas vehicles.
    NHTSA Enforcement means the NHTSA Associate Administrator for 
Enforcement, or his or her designee.
    Party means the person alleged to have committed a violation of 
Sec.  535.9, and includes manufacturers of vehicles and manufacturers 
of engines.
    Payload means in this part the resultant of subtracting the curb 
weight from the gross vehicle weight rating.
    Petroleum has the meaning given in 40 CFR 1036.801.
    Pickup truck has the meaning given in 49 CFR part 523.
    Plug-in hybrid electric vehicle (PHEV) means a hybrid electric 
vehicle that has the capability to charge the battery or batteries used 
for vehicle propulsion from an off-vehicle electric source, such that 
the off-vehicle source cannot be connected to the vehicle while the 
vehicle is in motion.
    Power take-off (PTO) means a secondary engine shaft or other system 
on a vehicle that provides substantial auxiliary power for purposes 
unrelated to vehicle propulsion or normal vehicle accessories such as 
air conditioning, power steering, and basic electrical accessories. A 
typical PTO uses a secondary shaft on the engine to transmit power to a 
hydraulic pump that powers auxiliary equipment such as a boom on a 
bucket truck.
    Primary intended service class has the meaning for engines as 
specified in 40 CFR 1036.140.
    Rechargeable Energy Storage System (RESS) means the component(s) of 
a hybrid engine or vehicle that store recovered energy for later use, 
such as the battery system in a electric hybrid vehicle.
    Regulatory category means each of the three types of heavy-duty 
vehicles defined in 49 CFR 523.6 and the heavy-duty engines used in 
these heavy-duty vehicles.
    Regulatory subcategory means the sub-groups in each regulatory 
category to which fuel consumption requirements apply, and are defined 
as follows:
    (1) Heavy-duty pick-up trucks and vans.
    (2) Vocational light-heavy vehicles at or below 19,500 pounds GVWR.
    (3) Vocational medium-heavy vehicles above 19,500 pounds GVWR but 
at or below 33,000 pounds GVWR.
    (4) Vocational heavy-heavy vehicles above 33,000 pounds GVWR.
    (5) Low roof day cab tractors with a GVWR above 26,000 pounds but 
at or below 33,000 pounds.
    (6) Mid roof day cab tractors with a GVWR above 26,000 pounds but 
at or below 33,000 pounds.
    (7) High roof day cab tractors with a GVWR above 26,000 pounds but 
at or below 33,000 pounds.
    (8) Low roof day cab tractors above 33,000 pounds GVWR.
    (9) Mid roof day cab tractors above 33,000 pounds GVWR.
    (10) High roof day cab tractors above 33,000 pounds GVWR.
    (11) Low roof sleeper cab tractors above 33,000 pounds GVWR.
    (12) Mid roof sleeper cab tractors above 33,000 pounds GVWR.
    (13) High roof sleeper cab tractors above 33,000 pounds GVWR.
    (14) Compression-ignition light heavy-duty engines in Class 2b to 5 
vehicles with a GVWR above 8,500 pounds but at or below 19,500 pounds.
    (15) Compression-ignition medium heavy-duty engines in Class 6 and 
7 vocational vehicles with a GVWR above 19,500 but at or below 33,000 
pounds.
    (16) Compression-ignition heavy heavy-duty engines in Class 8 
vocational vehicles with a GVWR above 33,000 pounds.
    (17) Compression-ignition medium heavy-duty engines in Class 7 
tractors

[[Page 57496]]

with a GVWR above 26,000 pounds but at or below 33,000 pounds.
    (18) Compression-ignition heavy heavy-duty engines in Class 8 
tractors with a GVWR above 33,000 pounds.
    (19) Spark-ignition engines in Class 2b to 8 vehicles with a GVWR 
above 8,500 pounds.
    Roof height means the maximum height of a vehicle (rounded to the 
nearest inch), excluding narrow accessories such as exhaust pipes and 
antennas, but including any wide accessories such as roof fairings. 
Measure roof height of the vehicle configured to have its maximum 
height that will occur during actual use, with properly inflated tires 
and no driver, passengers, or cargo onboard. Determine the base roof 
height on fully inflated tires having a static loaded radius equal to 
the arithmetic mean of the largest and smallest static loaded radius of 
tires a manufacturer offers or a standard tire EPA approves. If a 
vehicle is equipped with an adjustable roof fairing, measure the roof 
height with the fairing in its lowest setting. Once the maximum height 
is determined, roof heights are divided into the following categories:
    (1) Low-roof means a vehicle with a roof height of 120 inches or 
less.
    (2) Mid-roof means a vehicle with a roof height between 121 and 147 
inches.
    (3) High-roof means a vehicle with a roof height of 148 inches or 
more.
    Service class group means a group of engine and vehicle averaging 
sets defined as follows:
    (1) Spark-ignition engines, light heavy-duty compression-ignition 
engines, light heavy-duty vocational vehicles and heavy-duty pickup 
trucks and vans.
    (2) Medium heavy-duty compression-ignition engines and medium 
heavy-duty vocational vehicles and tractors.
    (3) Heavy heavy-duty compression-ignition engines and heavy heavy-
duty vocational vehicles and tractors.
    Sleeper cab means a type of truck cab that has a compartment behind 
the driver's seat intended to be used by the driver for sleeping. This 
includes both cabs accessible from the driver's compartment and those 
accessible from outside the vehicle.
    Spark-ignition engines means relating to a gasoline-fueled engine 
or any other type of engine with a spark plug (or other sparking 
device) and with operating characteristics significantly similar to the 
theoretical Otto combustion cycle. Spark-ignition engines usually use a 
throttle to regulate intake air flow to control power during normal 
operation.
    Subconfiguration means a unique combination within a vehicle 
configuration of equivalent test weight, road-load horsepower, and any 
other operational characteristics or parameters that EPA determines may 
significantly affect CO2 emissions within a vehicle 
configuration.
    Test group means the multiple vehicle lines and model types that 
share critical emissions and fuel consumption related features and that 
are certified as a group by a common certificate of conformity issued 
by EPA and is used collectively with other test groups within an 
averaging set or regulatory subcategory and is used by NHTSA for 
determining the fleet average fuel consumption.
    Tire rolling resistance level (TRRL) means a value with units of 
kg/metric ton that represents that rolling resistance of a tire 
configuration. TRRLs are used as inputs to the GEM model under 40 CFR 
1037.520. Note that a manufacturer may assign a value higher than a 
measured rolling resistance of a tire configuration.
    Towing capacity in this part is equal to the resultant of 
subtracting the gross vehicle weight rating from the gross combined 
weight rating.
    Trade means to exchange fuel consumption credits, either as a buyer 
or a seller.
    Truck tractor has the meaning given in 49 CFR 571.3. This includes 
most heavy-duty vehicles specifically designed for the primary purpose 
of pulling trailers, but does not include vehicles designed to carry 
other loads. For purposes of this definition ``other loads'' would not 
include loads carried in the cab, sleeper compartment, or toolboxes. 
Examples of vehicles that are similar to tractors but that are not 
tractors under this part include dromedary tractors, automobile 
haulers, straight trucks with trailers hitches, and tow trucks.
    U.S.-directed production volume means the number of vehicle units, 
subject to the requirements of this part, produced by a manufacturer 
for which the manufacturer has a reasonable assurance that sale was or 
will be made to ultimate purchasers in the United States.
    Useful life has the meaning given in 40 CFR 1037.801.
    Vehicle configuration means a unique combination of vehicle 
hardware and calibration (related to measured or modeled emissions) 
within a vehicle family. Vehicles with hardware or software 
differences, but that have no hardware or software differences related 
to measured or modeled emissions or fuel consumption can be included in 
the same vehicle configuration. Note that vehicles with hardware or 
software differences related to measured or modeled emissions or fuel 
consumption are considered to be different configurations even if they 
have the same GEM inputs and FEL. Vehicles within a vehicle 
configuration differ only with respect to normal production variability 
or factors unrelated to measured or modeled emissions and fuel 
consumption for EPA and NHTSA.
    Vehicle family has the meaning given in 40 CFR 1037.230.
    Vehicle service class has the meaning for vehicles as specified in 
the 40 CFR 1037.801.
    Vocational tractor has the meaning given in 40 CFR 1037.630.
    Zero emissions vehicle means an electric vehicle or a fuel cell 
vehicle.

Sec.  535.5  Standards.

    (a) Heavy-duty pickup trucks and vans. Each manufacturer of a fleet 
of heavy-duty pickup trucks and vans shall comply with the fuel 
consumption standards in this paragraph (a) expressed in gallons per 
100 miles. If the manufacturer's fleet includes conventional vehicles 
(gasoline, diesel and alternative fueled vehicles) and advanced 
technology vehicles (hybrids with regenerative braking, vehicles 
equipped with Rankine-cycle engines, electric and fuel cell vehicles), 
it should divide its fleet into two separate fleets each with its own 
separate fleet average fuel consumption standard which a manufacturer 
must comply with the requirements of this paragraph (a).
    (1) Mandatory standards. For model years 2016 and later, each 
manufacturer must comply with the fleet average standard derived from 
the unique subconfiguration target standards (or groups of 
subconfigurations approved by EPA in accordance with 40 CFR 1037.104) 
of the model types that make up the manufacturer's fleet in a given 
model year. Each subconfiguration has a unique attribute-based target 
standard, defined by each group of vehicles having the same payload, 
towing capacity and whether the vehicles are equipped with a 2-wheel or 
4-wheel drive configuration.
    (2) Subconfiguration target standards. (i) Two alternatives exist 
for determining the subconfiguration target standards for model years 
2016 and later. For each alternative, separate standards exist for 
compression-ignition and spark-ignition vehicles:
    (A) The first alternative allows manufacturers to determine a fixed 
fuel consumption standard that is constant over the model years; and
    (B) The second alternative allows manufacturers to determine 
standards that are phased-in gradually each year.

[[Page 57497]]

    (ii) Calculate the subconfiguration target standards as specified 
in this paragraph (a)(2)(ii), using the appropriate coefficients from 
Table 1 choosing between the alternatives in paragraphs (a)(2)(i)(A) 
and (B) of this section. For electric or fuel cell heavy-duty vehicles, 
use compression-ignition vehicle coefficients ``c'' and ``d'' and for 
hybrid (including plug-in hybrid), dedicated and dual-fueled vehicles, 
use coefficients ``c'' and ``d'' appropriate for the engine type used. 
Round each standard to the nearest 0.01 gallons per 100 miles and 
specify all weights in pounds rounded to the nearest pound. Calculate 
the subconfiguration target standards using the following equation:
    Subconfiguration Target Standard (gallons per 100 miles) = [c x 
(WF)] + d

Where:

WF = Work Factor = [0.75 x (Payload Capacity + Xwd)] + [0.25 x 
Towing Capacity]
Xwd = 4wd Adjustment = 500 lbs if the vehicle group is equipped with 
4wd and all-wheel drive, otherwise equals 0 lbs for 2wd.
Payload Capacity = GVWR (lbs)-Curb Weight (lbs) (for each vehicle 
group)
Towing Capacity = GCWR (lbs)-GVWR (lbs) (for each vehicle group)

  Table 1--Equation Coefficients for Subconfiguration Target Standards
------------------------------------------------------------------------
                  Model year                         c            d
------------------------------------------------------------------------
                  Alternative 1--Fixed Target Standards
------------------------------------------------------------------------
Compression-ignition Vehicle Coefficients for Model Years 2016 and later
------------------------------------------------------------------------
2016-2018.....................................     0.000432         3.33
2019 and later................................     0.000409         3.14
------------------------------------------------------------------------
   Spark-ignition Vehicle Coefficients for Model Years 2016 and later
------------------------------------------------------------------------
2016-2018.....................................     0.000513         3.96
2019 and later................................     0.000495         3.81
------------------------------------------------------------------------
                Alternative 2--Phased-in Target Standards
------------------------------------------------------------------------
Compression-ignition Vehicle Coefficients for Model Years 2016 and later
------------------------------------------------------------------------
2016..........................................     0.000452         3.48
2017..........................................     0.000437         3.37
2018 and later................................     0.000409         3.14
------------------------------------------------------------------------
   -Spark-ignition Vehicle Coefficients for Model Years 2016 and later
------------------------------------------------------------------------
2016..........................................     0.000528         4.07
2017..........................................     0.000518         3.98
2018 and later................................     0.000495         3.81
------------------------------------------------------------------------

    (3) Fleet average fuel consumption standard. (i) Calculate each 
manufacturer's fleet average fuel consumption standard for conventional 
and advanced technology fleets separately based on the subconfiguration 
target standards specified in paragraph (a)(2) of this section, 
weighted to production volumes and averaged using the following 
equation combining all the applicable vehicles in a manufacturer's U.S. 
directed fleet (compression-ignition, spark-ignition and advanced 
technology vehicles) for a given model year, rounded to the nearest 
0.01 gallons per 100 miles:
[GRAPHIC] [TIFF OMITTED] TR15SE11.106

Where:

Subconfiguration Target Standardi = fuel consumption 
standard for each group of vehicles with same payload, towing 
capacity and drive configuration (gallons per 100 miles).
Volumei = production volume of each unique 
subconfiguration of a model type based upon payload, towing capacity 
and drive configuration.

    (A) A manufacturer may group together subconfigurations that have 
the same test weight (ETW), GVWR, and GCWR. Calculate work factor and 
target value assuming a curb weight equal to two times ETW minus GVWR.
    (B) A manufacturer may group together other subconfigurations if it 
uses the lowest target value calculated for any of the 
subconfigurations.
    (C) The fleet average shall also be derived in accordance with 40 
CFR 86.1865 and 40 CFR 1037.104(d).
    (ii) A manufacturer complies with the requirements of this part if 
it provides reports, as specified in Sec.  535.8, by the required 
deadlines and meets one of the following conditions:
    (A) The manufacturer's fleet average performance, as determined in 
Sec.  535.6, is less than the fleet average standard; or
    (B) The manufacturer uses one or more of the credit flexibilities 
provided under NHTSA's Averaging, Banking and Trading Program, as 
specified in Sec.  535.7, to comply with standards.
    (iii) Manufacturers must select an alternative for subconfiguration 
target standards at the same time they submit the model year 2016 Pre-
Model year Report, specified in Sec.  535.8. Once selected, the 
decision cannot be reversed and the manufacturer must continue to 
comply with the same alternative for subsequent model years.
    (iv) A manufacturer failing to comply with the provisions specified 
in paragraph (a)(3)(ii) of this section is liable to pay civil 
penalties in accordance with Sec.  535.9.
    (4) Voluntary standards. (i) Manufacturers may choose voluntarily 
to comply early with fuel consumption standards for model years 2013 
through 2015, as determined in paragraphs (a)(4)(iii) and (iv) of this 
section, for example, in order to begin accumulating credits through 
over-compliance with the applicable standard. A manufacturer choosing 
early compliance must comply with all the vehicles and engines it 
manufactures in each regulatory category for a given model year.
    (ii) A manufacturer must declare its intent to voluntarily comply 
with fuel consumption standards at the same time it submits a Pre-Model 
Report, prior to the compliance model year beginning as specified in 
Sec.  535.8; and, once selected, the decision cannot be reversed and 
the manufacturer must continue to comply for each subsequent model year 
for all the vehicles and engines it manufactures in each regulatory 
category for a given model year.
    (iii) Calculate separate subconfiguration target standards for 
compression-ignition and spark-ignition vehicles for model years 2013 
through 2015 using the equation in paragraph (a)(2)(ii) of this 
section, substituting the appropriate values for the coefficients in 
Table 2 of this section as appropriate.

[[Page 57498]]

  Table 2--Voluntary Compliance Equation Coefficients for Vehicle Fuel
                          Consumption Standards
------------------------------------------------------------------------
                  Model Year                         c            d
------------------------------------------------------------------------
  Compression-ignition Vehicle Coefficients for Voluntary Compliance in
                      Model Years 2013 through 2015
------------------------------------------------------------------------
2013 and 14...................................     0.000470         3.61
2015..........................................     0.000466         3.60
------------------------------------------------------------------------
  Spark-ignition Vehicle Coefficients for Voluntary Compliance in Model
                         Years 2013 through 2015
------------------------------------------------------------------------
2013 and 14...................................     0.000542         4.17
2015..........................................     0.000539         4.15
------------------------------------------------------------------------

    (iv) Calculate the fleet average fuel consumption standards for 
model years 2013 through 2015 using the equation in paragraph (a)(3) of 
this section.
    (5) Exclusion of vehicles not certified as complete vehicles. The 
vehicle standards Sec.  535.5(a) do not apply for vehicles that are 
chassis-certified with respect to EPA's criteria pollutant test 
procedure in 40 CFR part 86, subpart S. Any chassis-certified vehicles 
must comply with the vehicle standards and requirements of Sec.  
535.5(b) and the engine standards of Sec.  535.5(d) for engines used in 
these vehicles. A vehicle manufacturer choosing to comply with this 
paragraph and that is not the engine manufacturer is required to notify 
the engine manufacturers that their engines are subject to Sec.  
535.5(d) and that it intends to use their engines in excluded vehicles.
    (6) Optional certification under this section. Manufacturers may 
certify any complete or cab-complete Class 2b through 5 vehicles 
weighing at or below 19,500 pounds GVWR and any incomplete vehicles 
approved by EPA for inclusion under this paragraph to the same testing 
and standard that applies to a comparable complete sister vehicles as 
determined in accordance in 40 CFR 1037.150(l). Calculate the target 
standard value under paragraph (a)(2) of this section based on the same 
work factor value that applies for the complete sister vehicle.
    (7) Loose engines. This paragraph applies for spark-ignition 
engines identical to engines used in vehicles certified to the 
standards of this section Sec.  535.5(a), where manufacturers sell such 
engines as loose engines or installed in incomplete vehicles that are 
not cab-complete vehicles in accordance with 40 CFR 1037.150(m). A 
manufacturer's engines are deemed to have fuel consumption target 
values and test results based upon the complete vehicle in the 
applicable test group with the highest equivalent test weight in 
accordance with 40 CFR 1037.150(m). The fuel consumption 
subconfiguration standard for a loose engines equals the test group 
result of the complete vehicle as specified in 40 CFR 1037.150(m)(6) 
multiplied by 1.10 and rounded to the nearest 0.01 gallon per 100 
miles. The U.S.-directed production volume of engines manufactured for 
sale as loose engines or installed in incomplete heavy-duty vehicles 
that are not cab-complete vehicles in any given model year may not 
exceed ten percent of the total U.S-directed production volume of 
engines of that design that the manufacturer produces for heavy-duty 
applications for that model year, including engines the manufacturer 
produces for complete vehicles, cab-complete vehicles, and other 
incomplete vehicles. The total number of engines a manufacturer may 
certify under this paragraph (a)(7), of all engine designs, may not 
exceed 15,000 in any model year as specified in 40 CFR 1037.150(m). 
Engines produced in excess of the number cannot be certified to the 
standard in this paragraph (a)(7).
    (b) Heavy-duty vocational vehicles. Each chassis manufacturer of 
heavy-duty vocational vehicles shall comply with the fuel consumption 
standards in this paragraph (b) expressed in gallons per 1,000 ton-
miles. Manufacturers of engines used in heavy-duty vocational vehicles 
shall comply with the standards in paragraph (d) of this section.
    (1) Mandatory standards. For model years 2016 and later, each 
chassis manufacturer of heavy-duty vocational vehicles must comply with 
the fuel consumption standards in paragraph (b)(3) of this section.
    (i) The heavy-duty vocational vehicle chassis category is 
subdivided by GVWR into three regulatory subcategories as defined in 
Sec.  535.4, each with its own assigned standard.
    (ii) For purposes of certifying vehicles to fuel consumption 
standards, manufacturers must divide their product lines into vehicle 
families that have similar emissions and fuel consumption features, as 
specified by EPA in 40 CFR part 1037, subpart C, and these families 
will be subject to the applicable standards. Each vehicle family is 
limited to a single model year.
    (iii) A manufacturer complies with the requirements of this part, 
if it provides information as specified in Sec.  535.8, by the required 
deadlines and meets one of the following conditions:
    (A) The manufacturer's fuel consumption performance for each 
vehicle family, as determined in Sec.  535.6, is lower than the 
applicable standard; or
    (B) The manufacturer uses one or more of the credit flexibilities 
provided under NHTSA's Averaging, Banking and Trading Program, 
specified in Sec.  535.7, to comply with standards.
    (iv) A manufacturer failing to comply with the provisions specified 
in paragraph (b)(1)(iii) of this section is liable to pay civil 
penalties in accordance with Sec.  535.9.
    (2) Voluntary compliance. (i) For model years 2013 through 2015, a 
manufacturer may choose voluntarily to comply early with the fuel 
consumption standards provided in paragraph (b)(3) of this section. For 
example, a manufacturer may choose to comply early in order to begin 
accumulating credits through over-compliance with the applicable 
standards. A manufacturer choosing early compliance must comply with 
all the vehicles and engines it manufacturers in each regulatory 
category for a given model year.
    (ii) A manufacturer must declare its intent to voluntarily comply 
with fuel consumption standards and identify its plans to comply before 
it submits its first application for a certificate of conformity for 
the respective model year as specified in Sec.  535.8; and, once 
selected, the decision cannot be reversed and the manufacturer must 
continue to comply for each subsequent model year for all the vehicles 
and engines it manufacturers in each regulatory category for a given 
model year.
    (3) Regulatory subcategory standards. The fuel consumption 
standards for heavy-duty vocational vehicles are given in the following 
table:

[[Page 57499]]

                        Table 3--Heavy-Duty Vocational Vehicle Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
                                         Light Heavy vehicles    Medium heavy vehicles     Heavy heavy vehicles
       Regulatory subcategories               Class 2b-5               Class 6--7                Class 8
----------------------------------------------------------------------------------------------------------------
   Fuel Consumption Mandatory Standards (gallons per 1,000 ton-miles) Effective for Model Years 2017 and later
----------------------------------------------------------------------------------------------------------------
Fuel Consumption Standard............                     36.7                     22.1                     21.8
----------------------------------------------------------------------------------------------------------------
                                         Effective for Model Years 2016
----------------------------------------------------------------------------------------------------------------
Fuel Consumption Standard............                     38.1                     23.0                     22.2
----------------------------------------------------------------------------------------------------------------
    Fuel Consumption Voluntary Standards (gallons per 1,000 ton-miles) Effective for Model Years 2013 to 2015
----------------------------------------------------------------------------------------------------------------
Fuel Consumption Standard............                     38.1                     23.0                     22.2
----------------------------------------------------------------------------------------------------------------

    (4) Certifying across service classes. A manufacturer may 
optionally certify a vocational vehicle to the standards and useful 
life applicable to a higher vehicle service class (or regulatory 
subcategory changes such as complying with the heavy heavy-duty 
standard instead of medium heavy-duty standard), provided the 
manufacturer does not generate credits with the vehicle. If a 
manufacturer includes smaller vehicles in a credit-generating subfamily 
(with an FEL below the standard), exclude their production volume from 
the credit calculation.
    (5) Off-road operation. Heavy-duty vocational vehicles including 
vocational tractors meeting the off-road criteria in 49 CFR 523.2 are 
exempted from the requirements in this paragraph (b), but the engines 
in these vehicles must meet the requirements of paragraph (d) of this 
section.
    (c) Truck tractors. Each manufacturer of truck tractors, except 
vocational tractors, with a GVWR above 26,000 pounds shall comply with 
the fuel consumption standards in this paragraph (c) expressed in 
gallons per 1,000 ton-miles.
    (1) Mandatory standards. For model years 2016 and later, each 
manufacturer of truck tractors must comply with the fuel consumption 
standards in paragraph (c)(3) of this section.
    (i) The truck tractor category is subdivided by roof height and cab 
design into nine regulatory subcategories as shown in Table 4 of this 
section, each with its own assigned standard.
    (ii) For purposes of certifying vehicles to fuel consumption 
standards, manufacturers must divide their product lines into vehicles 
families that have similar emissions and fuel consumption features, as 
specified by EPA in 40 CFR part 1037, subpart C, and these families 
will be subject to the applicable standards. Each vehicle family is 
limited to a single model year.
    (iii) Standards for truck tractor engines are given in paragraph 
(d) of this section.
    (iv) A manufacturer complies with the requirements of this part, if 
at the end of the model year, it provides reports, as specified in 
Sec.  535.8, by the required deadlines and meets one of the following 
conditions:
    (A) The manufacturer's fuel consumption performance for each 
vehicle family, as determined in Sec.  535.6, is lower than the 
applicable standard; or
    (B) The manufacturer uses one or more of the credit flexibilities 
provided under NHTSA's Averaging, Banking and Trading Program, 
specified in Sec.  535.7, to comply with standards.
    (v) A manufacturer failing to comply with the provisions specified 
in paragraph (c)(1)(iv) of this section is liable to pay civil 
penalties in accordance with Sec.  535.9.
    (2) Voluntary compliance. (i) For model years 2013 through 2015, a 
manufacturer may choose voluntarily to comply early with the fuel 
consumption standards provided in paragraph (c)(3) of this section. For 
example, a manufacturer may choose to comply early in order to begin 
accumulating credits through over-compliance with the applicable 
standards. A manufacturer choosing early compliance must comply with 
all the vehicles and engines it manufacturers in each regulatory 
category for a given model year.
    (ii) A manufacturer must declare its intent to voluntarily comply 
with fuel consumption standards and identify its plans to comply before 
it submits its first application for a certificate of conformity for 
the respective model year as specified in Sec.  535.8; and, once 
selected, the decision cannot be reversed and the manufacturer must 
continue to comply for each subsequent model year for all the vehicles 
and engines it manufacturers in each regulatory category for a given 
model year.
    (3) Regulatory subcategory standards. The fuel consumption 
standards for truck tractors, except for vocational tractors, are given 
in the following table:

                                Table 4--Truck Tractor Fuel Consumption Standards
----------------------------------------------------------------------------------------------------------------
                                                            Day cab                            Sleeper cab
       Regulatory subcategories       --------------------------------------------------------------------------
                                               Class 7                  Class 8                  Class 8
----------------------------------------------------------------------------------------------------------------
   Fuel Consumption Mandatory Standards (gallons per 1,000 ton-miles) Effective for Model Years 2017 and later
----------------------------------------------------------------------------------------------------------------
Low Roof.............................                     10.2                      7.8                      6.5
Mid Roof.............................                     11.3                      8.4                      7.2
High Roof............................                     11.8                      8.7                      7.1
----------------------------------------------------------------------------------------------------------------
                                         Effective for Model Years 2016
----------------------------------------------------------------------------------------------------------------
Low Roof.............................                     10.5                      8.0                      6.7
Mid Roof.............................                     11.7                      8.7                      7.4

[[Page 57500]]

 
High Roof............................                     12.2                      9.0                      7.3
----------------------------------------------------------------------------------------------------------------
    Fuel Consumption Voluntary Standards (gallons per 1,000 ton-miles) Effective for Model Years 2013 to 2015
----------------------------------------------------------------------------------------------------------------
Low Roof.............................                     10.5                      8.0                      6.7
Mid Roof.............................                     11.7                      8.7                      7.4
High Roof............................                     12.2                      9.0                      7.3
----------------------------------------------------------------------------------------------------------------

    (4) Certifying across service classes. A manufacturer may 
optionally certify a tractor to the standards and useful life 
applicable to a higher vehicle service class (or regulatory subcategory 
changes such as complying with the Class 8 day-cab tractor standard 
instead of Class 7 day-cab tractor), provided the manufacturer does not 
generate credits with the vehicle. If a manufacturer includes smaller 
vehicles in a credit-generating subfamily (with an FEL below the 
standard), exclude their production volume from the credit calculation.
    (5) Vocational tractors. Tractors meeting the definition of 
vocational tractors in 49 CFR 523.2 must comply with requirements for 
heavy-duty vocational vehicles specified in paragraphs (b) and (d) of 
this section. Class 7 and Class 8 tractors certified or exempted as 
vocational tractors are limited in production to no more than 21,000 
vehicles in any three consecutive model years. If a manufacturer is 
determined as not applying this allowance in good faith by the EPA in 
its applications for certification in accordance with 40 CFR 1037.205 
and 1037.610, a manufacturer must comply with the tractor fuel 
consumption standards in paragraph (c)(3) of this section.
    (d) Heavy-duty engines. Each manufacturer of heavy-duty engines 
shall comply with the fuel consumption standards in this paragraph (d) 
expressed in gallons per 100 brake-horsepower-hours. Each engine must 
be certified to the primary intended service class that it is designed 
for in accordance with 40 CFR 1036.108;
    (1) Mandatory standards. Each manufacturer must comply with the 
fuel consumption standard in paragraph (d)(3) of this section for model 
years 2017 and later compression-ignition engines and for model years 
2016 and later spark-ignition engines.
    (i) The heavy-duty engine regulatory category is divided into six 
regulatory subcategories, five compression-ignition subcategories and 
one spark-ignition subcategory, as shown in Table 5 of this section.
    (ii) Separate standards exist for engines manufactured for use in 
heavy-duty vocational vehicles and in truck tractors.
    (iii) For purposes of certifying engines to fuel consumption 
standards, manufacturers must divide their product lines into engine 
families that have similar fuel consumption features, as specified by 
EPA in 40 CFR part 1036, subpart C, and these families will be subject 
to the same standards. Each engine family is limited to a single model 
year.
    (iv) A manufacturer complies with the requirements of this part, if 
at the end of the model year, it provides reports, as specified in 
Sec.  535.8, by the required deadlines and meets one of the following 
conditions:
    (A) The manufacturer's fuel consumption performance of each engine 
family as determined in Sec.  535.6 is less than the applicable 
standard; or
    (B) The manufacturer uses one or more of the flexibilities provided 
under NHTSA's Averaging, Banking and Trading Program, specified in 
Sec.  535.7, to comply with standards.
    (v) A manufacturer failing to comply with the provisions specified 
in paragraph (d)(1)(iv) of this section is liable to pay civil 
penalties in accordance with Sec.  535.9.
    (2) Voluntary compliance. (i) For model years 2013 through 2016 for 
compression-ignition engines, and for model year 2015 for spark-
ignition engines, a manufacturer may choose voluntarily to comply with 
the fuel consumption standards provided in paragraph (d)(3) through (5) 
of this section. For example, a manufacturer may choose to comply early 
in order to begin accumulating credits through over-compliance with the 
applicable standards. A manufacturer choosing early compliance must 
comply with all the vehicles and engines it manufacturers in each 
regulatory category for a given model year except in model year 2013 
the manufacturer may comply with individual engine families as 
specified in 40 CFR 1036.150(a)(2).
    (ii) A manufacturer must declare its intent to voluntarily comply 
with fuel consumption standards and identify its plans to comply before 
it submits its first application for a certificate of conformity for 
the respective model year as specified in Sec.  535.8; and, once 
selected, the decision cannot be reversed and the manufacturer must 
continue to comply for each subsequent model year for all the vehicles 
and engines it manufacturers in each regulatory category for a given 
model year.
    (3) Regulatory subcategory standards. The fuel consumption 
standards for heavy-duty engines are given in the following:

                                                                          Table 5--Primary Heavy-Duty Engine Standards
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Fuel Consumption Mandatory Standards (gallons per 100 bhp-hr)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
     Regulatory Subcategory       Light Heavy-Duty Compression-        Medium Heavy-Duty Compression-Ignition Engine
                                   Ignition Engine.
                                         Heavy Heavy-Duty Compression-Ignition Engine         Spark-Ignition Engines.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Truck Application...............  Vocational.......................  Vocational.............  Tractor................  Vocational.............  Tractor................  All
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Effective Model Years...........                                                              2017 and later                                                             2016 and later
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 57501]]

 
Fuel Consumption Standard.......  5.66.............................  5.66...................  4.78...................  5.45...................  4.52...................  7.06
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Fuel Consumption Standards for Voluntary Compliance (gallons per100 bhp-hr)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Regulatory Subcategory..........  Light Heavy-Duty Compression-        Medium Heavy-Duty Compression-Ignition Engine
                                   Ignition Engine.
                                         Heavy Heavy-Duty Compression-Ignition Engine         Spark-ignition Engine..
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Truck Application...............  Vocational.......................  Vocational.............  Tractor................  Vocational.............  Tractor................  All
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Effective Model Years...........                                                            2013 through 2016                                                            2015
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Voluntary Fuel Consumption        5.89.............................  5.89...................  4.93...................  5.57...................  4.67...................  7.06
 Standard.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

     (4) Alternate subcategory standards. The alternative fuel 
consumption standards for heavy-duty compression-ignition engines are 
as follows:
    (i) Manufacturers entering the voluntary program in model years 
2014 through 2016, may choose to certify compression-ignition engine 
families unable to meet standards provided in paragraph (d)(3) of this 
section to the alternative fuel consumption standards of this paragraph 
(d)(4).
    (ii) Manufacturers may not certify engines to these alternate 
standards if they are part of an averaging set in which they carry a 
balance of banked credits. For purposes of this section, manufacturers 
are deemed to carry credits in an averaging set if they carry credits 
from advance technology that are allowed to be used in that averaging 
set in accordance with Sec.  535.7(d)(12).
    (iii) The emission standards of this section are determined as 
specified in EPA 40 CFR 1036.620(a) through (c) and should be converted 
to equivalent fuel consumption values.
    (5) Alternate Phase-In Standards. Manufacturers have the option to 
comply with EPA emissions standards for compression-ignition engines 
using an alternative phase-in schedule that correlates with the EPA OBD 
standards. If a manufacturer chooses to use the alternative phase-in 
schedule for meeting EPA standards and optionally chooses to comply 
early with the NHTSA fuel consumption program, it must use the same 
phase-in schedule beginning in model year 2013 for fuel consumption 
standards and must remain in the program for each model year 
thereafter. The fuel consumption standard for each model year of the 
alternative phase-in schedule is provided in Table 6 of this section. 
Note that engines certified to these standards are not eligible for 
early credits under Sec.  535.7.

                       Table 6--Alternative Phase-in Compression Ignition Engine Standards
----------------------------------------------------------------------------------------------------------------
               Tractors                      LHD Engines              MHD Engines              HHD Engines
----------------------------------------------------------------------------------------------------------------
Model Years 2013-2015................  NA.....................  5.03 gals/100 hp-hr....  4.76 gals./100 hp-hr
Model Years 2016 and later[dagger]...  NA.....................  4.78 gals./100 hp-hr...  4.52 gals/100 hp-hr
Vocational...........................  LHD Engines............  MHD Engines............  HHD Engines
Model Years 2013-2015................  6.07 gals/100 hp-hr....  6.07 gals/100 hp-hr....  5.67 gals/100 hp-hr
Model Years 2016 and later[dagger]...  5.66 gals/100 hp-hr....  5.66 gals/100 hp-hr....  5.45 gals/100 hp-hr
----------------------------------------------------------------------------------------------------------------
[dagger]Note: these alternate standards for 2016 and later are the same as the otherwise applicable standards
  for 2017 and later.

Sec.  535.6  Measurement and calculation procedures.

    (a) Heavy-duty pickup trucks and vans. This section describes the 
testing a manufacturer must perform for each model year and the method 
for determining the fleet fuel consumption performance to show 
compliance with the fleet average fuel consumption standard for heavy-
duty pickup trucks and vans in Sec.  535.5(a).
    (1) For each model year, the heavy-duty pickup trucks and vans 
selected by a manufacturer to comply with fuel consumption standards in 
Sec.  535.5(a) must be used to determine the manufacturer's fleet 
average fuel consumption performance. If the manufacturer's fleet 
includes conventional and advanced technology heavy-duty pickup trucks 
and vans, the fleet should be sub-divided into two separate vehicle 
fleets, with all of the conventional vehicles in one fleet and all of 
the advanced technology vehicles in the other fleet.
    (2) Vehicles in each fleet should be divided into test groups or 
subconfigurations according to EPA in 40 CFR part 86, subpart S, and 40 
CFR 1037.104.
    (3) Test and measure the CO2 emissions test results for 
the selected vehicles and determine the CO2 emissions test 
group result, in grams per mile in accordance with 40 CFR part 86, 
subpart S.
    (i) Perform exhaust testing on vehicles fueled by conventional and 
alternative fuels, including dedicated and dual fueled (multi-fueled 
and flexible fueled) vehicles and measure the CO2 emissions 
test result.
    (ii) Adjust the CO2 emissions test result of dual fueled 
vehicles using a weighted average of your emission results as specified 
in 40 CFR 600.510-12(k) for light-duty trucks.
    (iii) All electric vehicles are deemed to have zero emissions of 
CO2, CH4, and N2O. No emission testing is 
required for such electric vehicles. Assign the fuel consumption test 
group result to a value of zero gallons per 100 miles in paragraph 
(a)(4) of this section.
    (iv) Test cab-complete and incomplete vehicles using the applicable 
complete sister vehicles as determined in 40 CFR 1037.104(g).
    (v) Test loose engines using applicable complete vehicles as 
determined in 40 CFR 1037.104(h).
    (vi) Manufacturers can choose to analytically derive CO2 
emission rates (ADCs) for test groups or subconfigurations. Calculate 
the ADCs for test groups or subconfigurations in accordance with 40 CFR 
1037.104(g).

[[Page 57502]]

    (4) Calculate equivalent fuel consumption test group results, in 
gallons per 100 miles, from CO2 emissions test group 
results, in grams per miles, and round to the nearest 0.01 gallon per 
100 miles.
    (i) Calculate the equivalent fuel consumption test group results as 
follows for compression-ignition vehicles and alternative fuel 
compression-ignition vehicles. CO2 emissions test group 
result (grams per mile)/10,180 grams per gallon of diesel fuel) x 
(10\2\) = Fuel consumption test group result (gallons per 100 mile).
    (ii) Calculate the equivalent fuel consumption test group results 
as follows for spark-ignition vehicles and alternative fuel spark-
ignition vehicles. CO2 emissions test group result (grams 
per mile)/8,877 grams per gallon of gasoline fuel) x (10\2\) = Fuel 
consumption test group result (gallons per 100 mile).
    (5) Calculate the fleet average fuel consumption result, in gallons 
per 100 miles, from the equivalent fuel consumption test group results 
and round the fuel consumption result to the nearest 0.01 gallon per 
100 miles. Calculate the fleet average fuel consumption result using 
the following equation.
[GRAPHIC] [TIFF OMITTED] TR15SE11.107

Where:

Fuel Consumption Test Group Resulti = fuel consumption performance 
for each test group as defined in 49 CFR 523.4.
Volumei = production volume of each test group.

    (6) Compare the fleet average fuel consumption standard to the 
fleet average fuel consumption performance. The fleet average fuel 
consumption performance must be less than or equal to the fleet fuel 
consumption standard to comply with standards in Sec.  535.5(a).
    (b) Heavy-duty vocational vehicles and tractors. This section 
describes the testing a manufacturer must perform and the method for 
determining fuel consumption performance to show compliance with the 
fuel consumption standards for vocational vehicles and tractors in 
Sec.  535.5(b) and (c).
    (1) Select vehicles and vehicle family configurations to test as 
specified in 40 CFR 1037.230 for vehicles that make up each of the 
manufacture's regulatory subcategories of vocational vehicles and 
tractors.
    (2) Determine the CO2 emissions and fuel consumption 
results for all vehicle chassis (conventional, alternative fueled and 
advanced technology vehicles) using the Greenhouse Emissions Model 
(GEM) in accordance with 40 CFR part 1037, subpart F. Vocational 
vehicles and tractor chassis are modeled using the following inputs in 
the GEM model. All seven of the following inputs apply for sleeper cab 
tractors, while some do not apply for vocational vehicles and other 
tractor regulatory subcategories:
    (i) Identification of vehicles using regulatory subcategories (such 
as ``Class 8 Combination--Sleeper Cab--High Roof'').
    (ii) Coefficient of aerodynamic drag in accordance with 40 CFR 
1037.520 and 1037.521. Do not use for vocational vehicles.
    (iii) Steer tire rolling resistance for low rolling resistance 
tires in accordance with 40 CFR 1037.520 and 1037.650.
    (iv) Drive tire rolling resistance for low rolling resistance tires 
in accordance with 40 CFR 1037.520 and 1037.650.
    (v) Vehicle speed limit as governed by vehicles speed limiters in 
accordance with 40 CFR 1037.520 and 1037.640. Do not use for vocational 
vehicles.
    (vi) Vehicle weight reduction as provided in accordance with 40 CFR 
1037.520. Do not use for vocational vehicles.
    (vii) Extended idle reduction credit using automatic engine 
shutdown systems in accordance with 40 CFR 1037.520 and 1037.660. Do 
not use for vehicles other than Class 8 sleeper cabs.
    (3) From the GEM results, select the CO2 family 
emissions level (FEL) and equivalent fuel consumption values for 
vocational vehicle and tractor families in each regulatory 
subcategories for each model year. Equivalent fuel consumption FELs are 
derived in GEM and expressed to the nearest 0.1 gallons per 1000 ton-
mile. For families containing multiple subfamilies, identify the FELs 
for each subfamily.
    (4) Paragraphs (b)(1) through (3) of this section address 
vocational vehicle and tractor chassis testing only. Engine performance 
and the advanced technologies equipped on vocational vehicles and 
tractors are tested separately as follows:
    (i) Vocational vehicle and tractor engine test results for 
conventional and alternative fueled vehicles are determined in 
accordance with Sec.  535.6(c).
    (ii) Improvements for advanced technologies are determined as 
follows:
    (A) Test hybrid vehicles with power take-off in accordance with 40 
CFR 1037.525 and vehicles with post-transmission hybrid systems in 
accordance with 40 CFR 1037.550.
    (B) All electric vehicles are deemed to have zero CO2 
emissions and fuel consumption. No emission testing is required for 
such electric vehicles. Assign the vehicle family with a fuel 
consumption FEL result to a value of zero gallons per 1000-ton miles in 
paragraph (3) of this section.
    (c) Heavy-duty engines. This section describes the testing a 
manufacturer must perform and the method for determining fuel 
consumption performance to show compliance with the fuel consumption 
standards for engines in Sec.  535.5(d). Each engine must be tested to 
the primary intended service class that it is designed for in 
accordance with 40 CFR 1036.108
    (1) Select emission-data engines and engine family configurations 
to test as specified in 40 CFR part 86 and part 1036, subpart C for 
engines installed in vehicles that make up each of the manufacture's 
regulatory subcategory.
    (2) Test the CO2 emissions for each emissions-data 
engine subject to the standards in Sec.  535.5(d) using the procedures 
and equipment specified in 40 CFR part 1036, subpart F. Measure the 
CO2 emissions in grams per bhp-hr as specified in 40 CFR 
part 86, subpart N, and part 1036, subpart C.
    (i) Perform exhaust testing on each fuel type for conventional, 
dedicated, dual fuel (multi-fuel, and flexible fuel) vehicles and 
measure the CO2 emissions level.
    (ii) Adjust the CO2 emissions result of dual fueled 
vehicles using a weighted average of the demonstrated emission results 
as specified in 40 CFR 1036.225. If EPA disapproves a manufacturer's 
dual fuel vehicle demonstrated use submission, NHTSA will require the 
manufacturer to only use the test results with 100 percent conventional 
fuel to determine the fuel consumption of the engine.
    (iii) All electric vehicles are deemed to have zero emissions of 
CO2 and zero fuel consumption. No emission or fuel 
consumption testing is required for such electric vehicles.

[[Page 57503]]

    (3) Determine the CO2 emissions for the family 
certification level (FCL) from the emissions test results in paragraph 
(c)(2) of this section for engine families within the heavy-duty engine 
regulatory subcategories for each model year.
    (i) If a manufacturer certifies an engine family for use both as a 
vocational engine and as a tractor engine, the manufacturer must split 
the family into two separate subfamilies in accordance with 40 CFR 
1036.230. The manufacturer may assign the numbers and configurations of 
engines within the respective subfamilies at any time prior to the 
submission of the end-of-year report required by 40 CFR 1036.730 and 
Sec.  535.8. The manufacturer must track into which type of vehicle 
each engine is installed, although EPA may allow the manufacturer to 
use statistical methods to determine this for a fraction of its 
engines.
    (ii) The following engines are excluded from the engine families 
used to determined FCL values and the benefit for these engines is 
determined as an advanced technology credits under the ABT provisions 
provided in Sec.  535.7(e):
    (A) Engines certified as hybrid engines or power packs.
    (B) Engines certified as hybrid engines designed with PTO 
capability and that are sold with the engine coupled to a transmission.
    (C) Engines with Rankine cycle waste heat recovery.
    (4) Calculate equivalent fuel consumption values for emissions FCLs 
and the CO2 levels for certified engines, in gallons per 100 
bhp-hr and round each fuel consumption value to the nearest 0.01 gallon 
per 100 bhp-hr.
    (i) Calculate equivalent fuel consumption FCL values for 
compression-ignition engines and alternative fuel compression-ignition 
engines. CO2 FCL value (grams per bhp-hr)/10,180 grams per 
gallon of diesel fuel) x (10 \2\) = Fuel consumption FCL value (gallons 
per 100 bhp-hr).
    (ii) Calculate equivalent fuel consumption FCL values for spark-
ignition engines and alternative fuel spark-ignition engines. 
CO2 FCL value (grams per bhp-hr)/8,877 grams per gallon of 
gasoline fuel) x (10 \2\) = Fuel consumption FCL value (gallons per 100 
bhp-hr).
    (iii) Manufacturers may carryover fuel consumption data from a 
previous model year if allowed to carry over emissions data for EPA in 
accordance with 40 CFR 1036.235.
    (iv) If a manufacturer uses an alternate test procedure under 40 
CFR 1065.10 and subsequently the data is rejected by the EPA, NHTSA 
will also reject the data.

Sec.  535.7  Averaging, banking, and trading (ABT) program.

    (a) Fuel consumption credits (FCC). At the end of each model year, 
manufacturers may earn credits for heavy-duty vehicles and engines 
exceeding the fuel consumption standards in Sec.  535.5 or by using one 
or more of the flexibilities in this paragraph (a) to gain credits. 
Manufacturers may average, bank, and trade fuel consumption credits for 
purposes of complying with fuel consumption standards. The following 
criteria and restrictions apply to averaging, banking and trading FCC 
(hereafter reference as the NHTSA ABT program).
    (1) Averaging. Averaging is the exchange of FCC among a 
manufacturer's engines or vehicle families or test groups within an 
averaging set. With the exception of FCC earned for advance 
technologies as further clarified below, a manufacturer may average FCC 
only within the same averaging set. The principle averaging sets are 
defined in Sec.  535.4.
    (2) Banking. Banking is the retention of surplus FCC by the 
manufacturer generating the credits for use in future model years for 
averaging or trading. Banked FCC retain the designation from the 
averaging set and model year in which they were generated and expire 
after five model years.
    (3) Trading. Trading is a transaction that transfers FCC between 
manufacturers or other entities. A manufacturer may use traded FCC for 
averaging, banking, or further trading transactions. Traded FCC, other 
than advanced technology credits, may be used only within the averaging 
set in which they were generated.
    (b) ABT provisions for heavy-duty pickup trucks and vans. (1) This 
regulatory category consists of one regulatory subcategory, heavy-duty 
pickup trucks and vans. This one regulatory subcategory makes up one 
averaging set.
    (2) Manufacturers that manufacture vehicles within this regulatory 
subcategory shall calculate credits at the end of each model year based 
upon the final average fleet fuel consumption standard and final 
average fleet fuel consumption performance value within this one 
regulatory subcategory as identified in paragraph (b)(8) of this 
section. If the manufacturer's fleet includes conventional vehicles 
(gasoline, diesel and alternative fuel) and advanced technology 
vehicles (hybrids with regenerative braking, vehicles equipped with 
Rankine-cycle engines, electric and fuel cell vehicles) it should be 
divided into two separate fleets each with its own final average fleet 
fuel consumption standard and final average fleet fuel consumption 
performance value. Credits shall be calculated for each of the two 
fleets.
    (3) Fuel consumption levels below the standard create a ``credit 
surplus,'' while fuel consumption levels above the standard create a 
``credit shortfall.''
    (4) Surplus credits, other than advanced technology credits, 
generated and calculated within this averaging set may only be used to 
offset a credit shortfall in this same averaging set.
    (5) Advanced technology credits can be used to offset a credit 
shortfall in this same averaging set or other averaging sets. However, 
a manufacturer must first apply advanced technology credits to any 
deficits in the same averaging set before applying them to other 
averaging sets.
    (6) Surplus credits, other than advanced technology credits, may be 
traded among credit holders but must stay within the same averaging 
set. Advanced technology credits can be traded across averaging sets.
    (7) Surplus credits, if not used to offset a credit shortfall may 
be banked by the manufacturer for use in future model years, or traded, 
given the restriction that the credits have an expiration date of five 
model years after the year in which the credits are earned. For 
example, credits earned in model year 2014 may be utilized through 
model year 2019.
    (8) Credit shortfalls must be offset by an available credit surplus 
within three model years after the shortfall was incurred. If the 
shortfall cannot be offset, the manufacturer is liable for civil 
penalties as discussed in Sec.  535.9.
    (9) Calculate the value of credits generated in a model year for 
this regulatory subcategory or averaging set using the following 
equation:
Total MY Fleet FCC (gallons) = (Std - Act) x (Volume) x (UL) x (10 \2\)

Where:

Std = Fleet average fuel consumption standard (gal/100 mile).
Act = Fleet average actual fuel consumption value (gal/100 mile).
Volume = the total U.S.-directed production of vehicles in the 
regulatory subcategory.
UL = the useful life for the regulatory subcategory (120,000 miles).

    (10) If a manufacturer generates credits from its fleet of advanced 
technology vehicles in accordance with 535.7(e)(1) a multiplier of 1.5 
can be used. Advanced technology credits can be used in other averaging 
sets different

[[Page 57504]]

from the one they are generated within with the following restrictions.
    (i) The maximum amount of credits a manufacturer may bring into the 
service class group that contains the heavy-duty pickup and van 
averaging set is 5.89 Mgallons (for advanced technology credits based 
upon compression ignition engines) or 6.76 Mgallons (for advanced 
technology credits based upon spark-ignition engines) per model year as 
specified in 40 CFR 1037.104.
    (ii) The limit specified in paragraph (b)(10)(i) of this section 
does not limit the amount of advanced technology credits that can be 
used across averaging sets within the same service class group.
    (11) If a manufacturer chooses to generate CO2 emission 
credits under EPA provisions of 40 CFR 1037.150(a), it may also 
voluntarily generate early credits under the NHTSA fuel consumption 
program. Fuel consumption credits may be generated for vehicles 
certified in model year 2013 to the model year 2014 standards in Sec.  
535.5(a). To do so a manufacturer must certify its entire U.S. directed 
production volume of vehicles in its fleet. The same production volume 
restrictions specified in 40 CFR 1037.150(a)(2) relating to when test 
groups are certified apply to the NHTSA early credit provisions. 
Credits are calculated as specified in paragraph (b)(9) of this section 
relative to the fleet standard that would apply for model year 2014 
using the model year 2013 production volumes. Surplus credits generated 
under this paragraph are available credits for banking or trading. 
Credit deficits for an averaging set prior to model year 2014 do not 
carry over to model year 2014. These credits may be used to show 
compliance with the standards of this part for 2014 and later model 
years. Once a manufacturer opts into the NHTSA program they must stay 
in the program for all of the optional model years and remain 
standardized with the same implementation approach being followed to 
meet the EPA CO2 emission program.
    (c) ABT provisions for vocational vehicles and tractors. (1) The 
two regulatory categories for vocational vehicles and tractors consist 
of 12 regulatory subcategory as follows:
    (i) Vocational vehicles with a GVWR up to and including 19,500 
pounds (Light Heavy-Duty (LHD));
    (ii) Vocational vehicles with a GVWR above 19,500 pounds and no 
greater than 33,000 pounds (Medium Heavy-Duty (MHD));
    (iii) Vocational vehicles with a GVWR over 33,000 pounds (Heavy 
Heavy-Duty (HHD));
    (iv) Low roof day cab tractors with a GVWR above 26,000 pounds and 
no greater than 33,000 pounds;
    (v) Mid roof day cab tractors with a GVWR above 26,000 pounds and 
no greater than 33,000 pounds;
    (vi) High roof day cab tractors with a GVWR above 26,000 pounds and 
no greater than 33,000 pounds;
    (vii) Low roof day cab tractors with a GVWR above 33,000 pounds;
    (viii) Mid roof day cab tractors with a GVWR above 33,000 pounds;
    (ix) High roof day cab tractors with a GVWR above 33,000 pounds;
    (x) Low roof sleeper cab tractors with a GVWR above 33,000 pounds;
    (xi) Mid roof sleeper cab tractors with a GVWR above 33,000 pounds; 
and
    (xii) High roof sleeper cab tractors with a GVWR above 33,000 
pounds.
    (2) The 12 regulatory subcategories consist of three averaging sets 
as follows:
    (i) Vocational light-heavy vehicles at or below 19,500 pounds GVWR.
    (ii) Vocational and tractor medium-heavy vehicles above 19,500 
pounds GVWR but at or below 33,000 pounds GVWR.
    (iii) Vocational and tractor heavy-heavy vehicles above 33,000 
pounds GVWR.
    (3) Manufacturers that manufacture vehicles within either of these 
two vehicle categories, in one or more of the regulatory subcategories, 
shall calculate a total credit balance within each applicable averaging 
set at the end of each model year based upon final production volumes 
and the sum of the credit balances derived for each of the vehicle 
family groups within each averaging set.
    (4) Each designated vehicle family group has a ``family emissions 
limit'' (FEL) which is compared to the associated regulatory 
subcategory standard. A FEL that falls below the regulatory subcategory 
standard creates ``positive credits,'' while fuel consumption level of 
a family group above the standard creates a ``credit shortfall.''
    (5) Manufacturers shall sum all shortfalls and surplus credits for 
each vehicle family within each applicable averaging set to obtain the 
total credit balance for the model year before rounding. The sum of 
fuel consumptions credits must be rounded to the nearest gallon.
    (6) Surplus credits, other than advanced technology credits, 
generated and calculated within this averaging set may only be used to 
offset a credit shortfall in this same averaging set.
    (7) Advanced technology credits can be used to offset a credit 
shortfall in this same averaging set or other averaging sets. However, 
a manufacturer must first apply advanced technology credits to any 
deficits in the same averaging set before applying them to other 
averaging sets.
    (8) Surplus credits, other than advanced technology credits, may be 
traded among credit holders but must stay within the same averaging 
set. Advanced technology credits can be traded across averaging sets.
    (9) Surplus credits, if not used to offset a credit shortfall may 
be banked by the manufacturer for use in future model years, or traded, 
given the restriction that the credits have an expiration date of five 
model years after the year in which the credits are earned. For 
example, credits earned in model year 2014 may be utilized through 
model year 2019.
    (10) Credit shortfalls must be offset by an available credit 
surplus within three model years after the shortfall was incurred. If 
the shortfall cannot be offset, the manufacturer is liable for civil 
penalties as discussed in Sec.  535.9.
    (11) The value of credits generated in a model year is calculated 
as follows:
    (i) Calculate the value of credits generated in a model year for 
each vehicle family within an averaging set using the following 
equation:

Vehicle Family FCC (gallons) = (Std - FEL) x (Payload) x (Volume) x 
(UL) x (10 \3\)

Where:

Std = the standard for the respective vehicle family regulatory 
subcategory (gal/1000 ton-mile).
FEL = family emissions limit for the vehicle family (gal/1000 ton-
mile).
Payload = the prescribed payload in tons for each regulatory 
subcategory as shown in the following table:

------------------------------------------------------------------------
                                                                Payload
                   Regulatory subcategory                       (Tons)
------------------------------------------------------------------------
LHD Vocational Vehicles.....................................        2.85
MHD Vocational Vehicles.....................................        5.60
HHD Vocational Vehicles.....................................        7.5
Class 7 Tractor.............................................       12.50
Class 8 Tractor.............................................       19.00
------------------------------------------------------------------------

Volume = the number of U.S.-directed production volume of vehicles 
in the corresponding vehicle family.
UL = the useful life for the regulatory subcategory (miles) as shown 
in the following table:

------------------------------------------------------------------------
                                                                   UL
                    Regulatory subcategory                      (miles)
------------------------------------------------------------------------
LHD Vocational Vehicles......................................    110,000
MHD Vocational Vehicles......................................    185,000
HHD Vocational Vehicles......................................    435,000
Class 7 Tractor..............................................    185,000
Class 8 Tractor..............................................    435,000
------------------------------------------------------------------------

[[Page 57505]]

    (ii) Calculate the value of credits generated in a model year for 
each vehicle family for advanced technology vehicles within an 
averaging set using the equation above, the guidelines provided in 
paragraph (e)(1)(i) of this section, and the 1.5 credit multiplier.
    (iii) Calculate the total credits generated in a model year for 
each averaging set using the following equation:

Total averaging set MY credits = [Sigma] Vehicle family credits within 
each average set

    (12) If a manufacturer chooses to generate CO2 emission 
credits under EPA provisions of 40 CFR 1037.150(a), it may also 
voluntarily generate early credits under the NHTSA fuel consumption 
program as follows:
    (i) Fuel consumption credits may be generated for vehicles 
certified in model year 2013 to the model year 2014 standards in Sec.  
535.5(b) and (c). To do so a manufacturer must certify its entire U.S. 
directed production volume of vehicles. The same production volume 
restrictions specified in 40 CFR 1037.150(a)(1) relating to when test 
groups are certified apply to the NHTSA early credit provisions. 
Credits are calculated as specified in paragraph (c)(11) of this 
section relative to the standards that would apply for model year 2014. 
Surplus credits generated under this paragraph (c)(12) may be increased 
by a factor of 1.5 for determining total available credits for banking 
or trading. For example, if you have 10 gallons of surplus credits for 
model year 2013, you may bank 15 gallons of credits. Credit deficits 
for an averaging set prior to model year 2014 do not carry over to 
model year 2014. These credits may be used to show compliance with the 
standards of this part for 2014 and later model years. Once a 
manufacturer opts into the NHTSA program they must stay in the program 
for all of the optional model years and remain standardized with the 
same implementation approach being followed to meet the EPA 
CO2 emission program.
    (ii) A tractor manufacturer may generate fuel consumption credits 
for the number of additional SmartWay designated tractors (relative to 
its MY 2012 production), provided that credits are not generated for 
those vehicles under paragraph (c)(12)(i) of this section. Calculate 
credits for each regulatory sub-category relative to the standard that 
would apply in model year 2014 using the equations in paragraph (c)(11) 
of this section. Use a production volume equal to the number of 
verified model year 2013 SmartWay tractors minus the number of verified 
model year 2012 SmartWay tractors. A manufacturer may bank credits 
equal to the surplus credits generated under this paragraph multiplied 
by 1.50. A manufacturer's 2012 and 2013 model years must be equivalent 
in length. Once a manufacturer opts into the NHTSA program they must 
stay in the program for all of the optional model years and remain 
standardized with the same implementation approach being followed to 
meet the EPA CO2 emission program.
    (13) If a manufacturer generates credits from vehicles certified 
for advanced technology in accordance with Sec.  535.7(e)(1), a 
multiplier of 1.5 can be used, but this multiplier cannot be used on 
the same credits for which the early credit multiplier is used. 
Advanced technology credits can be used in other averaging sets 
different from the one they are generated, but the maximum amount of 
credits a manufacturer may bring into a service class group that 
contains the vocational vehicle and tractor averaging sets is 5.89 
Mgallons (for advanced technology credits based upon compression 
ignition engines) or 6.76 Mgallons (for advanced technology credits 
based upon spark-ignition engines) per model year as specified in 40 
CFR 1037.740. However, this does not limit the amount of advanced 
technology credits that can be used across averaging sets within the 
same service class group.
    (d) ABT provisions for heavy-duty engines. (1) Heavy-duty engines 
consist of six regulatory subcategories as follows:
    (i) Spark-ignition engines.
    (ii) Light heavy-duty compression-ignition engines.
    (iii) Medium heavy-duty vocational compression-ignition engines.
    (iv) Medium heavy-duty tractor compression-ignition engines.
    (v) Heavy heavy-duty vocational compression-ignition engines.
    (vi) Heavy heavy-duty tractor compression-ignition engines.
    (2) The six regulatory subcategories consist of four averaging sets 
as follows:
    (i) Compression-ignition light heavy-duty engines.
    (ii) Compression-ignition medium heavy-duty engines.
    (iii) Compression-ignition heavy heavy-duty engines.
    (iv) Spark-ignition engines.
    (3) Manufacturers that manufacture engines within one or more of 
the regulatory subcategories, shall calculate a total credit balance 
within each applicable averaging set at the end of each model year 
based upon final production volumes and the sum of the credit balances 
derived for each of the engine families within each averaging set.
    (4) Each designated engine family has a ``family certification 
level'' (FCL) which is compared to the associated regulatory 
subcategory standard. A FCL that falls below the regulatory subcategory 
standard creates ``positive credits,'' while fuel consumption level of 
a family group above the standard creates a ``credit shortfall.''
    (5) Manufacturers shall sum all surplus and shortfall credits for 
each engine family within the applicable averaging set to obtain the 
total credit balance for the model year before rounding. Round the sum 
of fuel consumptions credits to the nearest gallon.
    (6) Surplus credits, other than advanced technology credits, 
generated and calculated within this averaging set may only be used to 
offset a credit shortfall in this same averaging set.
    (7) Advanced technology credits can be used to offset a credit 
shortfall in this same averaging set or other averaging sets. However, 
a manufacturer must first apply advanced technology credits to any 
deficits in the same averaging set before applying them to other 
averaging sets.
    (8) Surplus credits, other than advanced technology credits, may be 
traded among credit holders but must stay within the same averaging 
set. Advanced technology credits can be traded across averaging sets.
    (9) Surplus credits, if not used to offset a credit shortfall may 
be banked by the manufacturer for use in future model years, or traded, 
given the restriction that the credits have an expiration date of five 
model years after the year in which the credits are earned. For 
example, credits earned in model year 2014 may be utilized through 
model year 2019.
    (10) Credit shortfalls must be offset by available surplus credits 
within three model years after shortfall was incurred. If the shortfall 
cannot be offset, the manufacturer is liable for civil penalties as 
discussed in Sec.  535.9.
    (11) The value of credits generated in a model year is calculated 
as follows:
    (i) The value of credits generated in a model year for each engine 
family within a regulatory subcategory equals
Engine Family FCC (gallons) = (Std - FCL) x (CF) x (Volume) x (UL) x 
(10 \2\)

Where:

Std = the standard for the respective engine regulatory subcategory 
(gal/100 bhp-hr).
FCL = family certification level for the engine family (gal/100 bhp-
hr).

[[Page 57506]]

CF = a transient cycle conversion factor in bhp-hr/mile which is the 
integrated total cycle brake horsepower-hour divided by the 
equivalent mileage of the applicable test cycle. For spark-ignition 
heavy-duty engines, the equivalent mileage is 6.3 miles. For 
compression-ignition heavy-duty engines, the equivalent mileage is 
6.5 miles.
Volume = the number of engines in the corresponding engine family.
UL = the useful life of the given engine family (miles) as shown in 
the following table:

------------------------------------------------------------------------
                                                                   UL
                    Regulatory subcategory                      (miles)
------------------------------------------------------------------------
Class 2b-5 Vocational Vehicles, Spark Ignited (SI), and Light    110,000
 Heavy-Duty Diesel Engines...................................
Class 6-7 Vocational Vehicles and Medium Heavy-Duty Diesel       185,000
 Engines.....................................................
Class 8 Vocational Vehicles and Heavy Heavy-Duty Diesel          435,000
 Engines.....................................................
Class 7 Tractors and Medium Heavy-Duty Diesel Engines........    185,000
Class 8 Tractors and Heavy Heavy-Duty Diesel Engines.........    435,000
------------------------------------------------------------------------

    (ii) Calculate the total credits generated in a model year for each 
averaging set using the following equation:
Total averaging set MY credits = [Sigma] Engine family credits within 
each averaging set

    (12) The provisions of this section apply to manufacturers 
utilizing the compression-ignition engine voluntary alternate standard 
provisions specified in Sec.  535.5(d)(4) as follows.
    (i) Manufacturers may not certify engines to the alternate 
standards if they are part of an averaging set in which they carry a 
balance of banked credits. For purposes of this section, manufacturers 
are deemed to carry credits in an averaging set if they carry credits 
from advance technology that are allowed to be used in that averaging 
set.
    (ii) Manufacturers may not bank fuel consumption credits for any 
engine family in the same averaging set and model year in which it 
certifies engines to the alternate standards. This means a manufacturer 
may not bank advanced technology credits in a model year it certifies 
any engines to the alternate standards.
    (iii) Note that the provisions of paragraph (d)(10) of this section 
apply with respect to credit deficits generated while utilizing 
alternate standards.
    (13) Where a manufacturer has chosen to comply with the EPA 
alternative compression ignition engine phase-in standard provisions in 
40 CFR 1036.150(e), and has optionally decided to follow the same path 
under the NHTSA fuel consumption program, it must certify all of its 
model year 2013 compression-ignition engines within a given averaging 
set to the applicable alternative standards in Sec.  535.5(d)(5). 
Engines certified to these standards are not eligible for early credits 
under paragraph (d)(14) of this section. Credits are calculated using 
the same equation provided in paragraph (d)(11) of this section.
    (14) If a manufacturer chooses to generate early CO2 
emission credits under EPA provisions of 40 CFR 1036.150, it may also 
voluntarily generate early credits under the NHTSA fuel consumption 
program. Fuel consumption credits may be generated for engines 
certified in model year 2013 (2015 for spark-ignition engines) to the 
standards in Sec.  535.5(d). To do so a manufacturer must certify its 
entire U. S.-directed production volume of engines except as specified 
in 40 CFR 1036.150(a)(2). Credits are calculated as specified in 
paragraph (d)(11) of this section relative to the standards that would 
apply for model year 2014 (2016 for spark-ignition engines). Surplus 
credits generated under this paragraph may be increased by a factor of 
1.5 for determining total available credits for banking or trading. For 
example, if you have 10 gallons of surplus credits for model year 2013, 
you may bank 15 gallons of credits. Credit deficits for an averaging 
set prior to model year 2014 (2016 for spark-ignition engines) do not 
carry over to model year 2014 (2016 for spark-ignition engines). These 
credits may be used to show compliance with the standards of this part 
for 2014 and later model years. Once a manufacturer opts into the NHTSA 
program they must stay in the program for all of the optional model 
years and remain standardized with the same implementation approach 
being followed to meet the EPA CO2 emission program.
    (15) If a manufacturer generates credits from engines certified for 
advanced technology in accordance with Sec.  535.7(e)(1), a multiplier 
of 1.5 can be used, but this multiplier cannot be used on the same 
credits for which the early credit multiplier is used. Advanced 
technology credits can be used in other averaging sets different from 
the one they are generated, but the maximum amount of credits a 
manufacturer may bring into a service class group that contains the 
heavy-duty engine averaging sets is 5.89 Mgallons (for advanced 
technology credits based upon compression ignition engines) or 6.76 
Mgallons (for advanced technology credits based upon spark-ignition 
engines) per model year as specified in 40 CFR 1036.740. However, this 
does not limit the amount of advanced technology credits that can be 
used across averaging sets within the same service class group.
    (e) Additional credit provisions. (1) Advanced technology credits. 
Manufacturers of heavy-duty pickup trucks and vans, vocational 
vehicles, tractors and associated engines showing improvements in 
CO2 emissions and fuel consumption using hybrid vehicles 
with regenerative braking, vehicles equipped with Rankine-cycle 
engines, electric vehicles and fuel cell vehicles are eligible for 
advanced technology credits. Advanced technology credits may be 
increased by a 1.5 multiplier and applied to any heavy-duty vehicle or 
engine subcategory consistent with sound engineering judgment.
    (i) Heavy-duty vehicles. (A) For advanced technology system (hybrid 
vehicles with regenerative braking, vehicles equipped with Rankine-
cycle engines and fuel cell vehicles), calculate the advanced 
technology credits as follows:
    (1) Measure the effectiveness of the advanced system by chassis 
testing a vehicle equipped with the advanced system and an equivalent 
conventional system in accordance with 40 CFR 1037.615.
    (2) For purposes of this paragraph (e), a conventional vehicle is 
considered to be equivalent if it has the same footprint, intended 
vehicle service class, aerodynamic drag, and other relevant factors not 
directly related to the advanced system powertrain. If there is no 
equivalent vehicle, the manufacturer may create and test a prototype 
equivalent vehicle. The conventional vehicle is considered Vehicle A, 
and the advanced technology vehicle is considered Vehicle B.
    (3) The benefit associated with the advanced system for fuel 
consumption is determined from the weighted fuel consumption results 
from the chassis tests of each vehicle using the following equation:

Benefit (gallon/1,000 ton mile) = Improvement Factor x GEM Fuel 
Consumption Result--B

Where:

Improvement Factor = (Fuel Consumption--A--Fuel Consumption--B)/
(Fuel Consumption--A)
Fuel Consumption Rates A and B are the gallons per 1,000 ton-mile of 
the conventional and advanced vehicles, respectively, as measured 
under the test procedures specified by EPA.
GEM Fuel Consumption Result B is the estimated gallons per 1,000 
ton-mile rate resulting from emission modeling of the

[[Page 57507]]

advanced vehicle as specified in 40 CFR 1037.520 and Sec.  535.6(b).

    (4) Calculate the benefit in credits using the equation in 
paragraph (c)(11) of this section and replacing the term (Std-FEL) with 
the benefit.
    (B) For electric vehicles calculate the fuel consumption credits 
using an FEL of 0 g/1000ton-mile.
    (ii) Heavy-duty engines. (A) This section specifies how to generate 
advanced technology-specific fuel consumption credits for hybrid 
powertrains that include energy storage systems and regenerative 
braking (including regenerative engine braking) and for engines that 
include Rankine-cycle (or other bottoming cycle) exhaust energy 
recovery systems.
    (1) Pre-transmission hybrid powertrains are those engine systems 
that include features that recover and store energy during engine 
motoring operation but not from the vehicle wheels. These powertrains 
are tested using the hybrid engine test procedures of 40 CFR part 1065 
or using the post-transmission test procedures.
    (2) Post-transmission hybrid powertrains are those powertrains that 
include features that recover and store energy from braking at the 
vehicle wheels. These powertrains are tested by simulating the chassis 
test procedure applicable for hybrid vehicles under 40 CFR 1037.550.
    (3) Test engines that include Rankine-cycle exhaust energy recovery 
systems according to the test procedures specified in 40 CFR part 1036, 
subpart F, unless EPA approves the manufacturer's alternate procedures.
    (B) Calculate credits as specified in paragraph (c) of this 
section. Credits generated from engines and powertrains certified under 
this section may be used in other averaging sets as described in 40 CFR 
1036.740(d).
    (2) Innovative technology credits. This provision allows engine and 
vehicle manufacturers to generate CO2 emission credits 
consistent with the provisions of 40 CFR 1036.610 (for engines), 40 CFR 
1037.104(d)(13) (for heavy-duty pickup trucks and vans) and 40 CFR 
1037.610 (for vocational vehicles and tractors) for introducing 
innovative technology in heavy-duty engines and vehicles for reducing 
greenhouse gas emissions and fuel consumption. Upon identification and 
approval from EPA of a manufacturer seeking to obtain innovative 
technology credits in a given model year, NHTSA may adopt an equivalent 
amount of fuel consumption credits into its program. Such credits must 
remain within the same regulatory subcategory in which the credits were 
generated. NHTSA will adopt these fuel consumption credits depending 
upon whether:
    (i) The technology has a direct impact upon reducing fuel 
consumption performance;
    (ii) The manufacturer has provided sufficient information to make 
sound engineering judgments on the impact of the technology in reducing 
fuel consumption performance; and
    (iii) Credits will be accepted on a one-for-one basis expressed in 
terms of gallons.

Sec.  535.8  Reporting requirements.

    (a) General requirements. Manufacturers producing heavy-duty 
vehicles and engines applicable to fuel consumption standards in Sec.  
535.5, for each given model year, must submit the required information 
as specified in paragraphs (b) through (h) of this section.
    (1) The information required by this part must be submitted by the 
deadlines specified in this section and must be based upon all the 
information and data available to the manufacturer 30 days before 
submitting information.
    (2) Manufacturers must submit information electronically through 
the EPA database system as the single point of entry for all 
information required for this national program and both agencies will 
have access to the information. The format for the required information 
is specified by EPA.
    (3) If by model year 2012 the agencies are not prepared to receive 
information through the EPA database system, manufacturers are required 
to submit information to EPA using an approved information format. A 
manufacturer can use a different format, if it sends EPA a written 
request with justification for a waiver.
    (b) Pre-model year reports. Manufacturers producing heavy-duty 
pickup trucks and vans must submit reports in advance of the model year 
providing early estimates demonstrating how their fleet(s) would comply 
with GHG emissions and fuel consumption standards. Note, the agencies 
understand that early model year reports contain estimates that may 
change over the course of a model year and that compliance information 
manufactures submit prior to the beginning of a new model year may not 
represent the final compliance outcome. The agencies view the necessity 
for requiring early model reports as a manufacturer's good faith 
projection for demonstrating compliance with emission and fuel 
consumption standards.
    (1) Report deadlines. For model years 2013 and later, manufacturer 
of heavy-duty pickup trucks and vans complying with voluntary and 
mandatory standards must submit a pre-model year report for the given 
model year as early as the date of the manufacturer's annual 
certification preview meeting with EPA and NHTSA, or prior to 
submitting its first application for a certificate of conformity to EPA 
in accordance with 40 CFR 1037.104(d). For example, a manufacturer 
choosing to comply in model year 2014 could submit its pre-model year 
report during its precertification meeting which could occur before 
January 2, 2013, or could provide its pre-model year report any time 
prior to submitting its first application for certification for the 
given model year.
    (2) Contents. Each pre-model year report must be submitted 
including the following information for each model year.
    (i) A list of each unique subconfiguration in the manufacturer's 
fleet describing the make and model designations, attribute based-
values (i.e., GVWR, GCWR, Curb Weight and drive configurations) and 
standards;
    (ii) The emission and fuel consumption fleet average standard 
derived from the unique vehicle configurations;
    (iii) The estimated vehicle configuration, test group and fleet 
production volumes;
    (iv) The expected emissions and fuel consumption test group results 
and fleet average performance;
    (v) If complying with MY 2013 fuel consumption standards, a 
statement must be provided declaring that the manufacturer is 
voluntarily choosing to comply early with the EPA and NHTSA programs. 
The manufacturers must also acknowledge that once selected, the 
decision cannot be reversed and the manufacturer will continue to 
comply with the fuel consumption standards for subsequent model years 
for all the vehicles it manufacturers in each regulatory category for a 
given model year;
    (vi) If complying with MYs 2014, 2015 or 2016 fuel consumption 
standards, a statement must be provided declaring whether the 
manufacturer will use fixed or increasing standards in accordance with 
Sec.  535.5(a). The manufacturer must also acknowledge that once 
selected, the decision cannot be reversed and the manufacturer must 
continue to comply with the same alternative for subsequent model years 
for all the vehicles it manufacturers in each regulatory category for a 
given model year;

[[Page 57508]]

    (vii) If complying with MYs 2014 or 2015 fuel consumption 
standards, a statement must be provided declaring that the manufacturer 
is voluntarily choosing to comply with NHTSA's voluntary fuel 
consumption standards in accordance with Sec.  535.5(a)(4). The 
manufacturers must also acknowledge that once selected, the decision 
cannot be reversed and the manufacturer will continue to comply with 
the fuel consumption standards for subsequent model years for all the 
vehicles it manufacturers in each regulatory category for a given model 
year;
    (viii) The list of Class 2b and 3 incomplete vehicles (cab-complete 
or chassis complete vehicles) and the method used to certify these 
vehicles as complete pickups and vans identifying the most similar 
complete sister- or other complete vehicles used to derive the target 
standards and performance test results;
    (ix) The list of Class 4 and 5 incomplete and complete vehicles and 
the method use to certify these vehicles as complete pickups and vans 
identifying the most similar complete or sister vehicles used to derive 
the target standards and performance test results;
    (x) List of loose engines included in the heavy-duty pickup and van 
category and the list of vehicles used to derive target standards and 
performance test results;
    (xi) Copy of any notices a vehicle manufacturer sends to the engine 
manufacturer to notify the engine manufacturers that their engines are 
subject to emissions and fuel consumption standards and that it intends 
to use their engines in excluded vehicles;
    (xii) A credit plan identifying the manufacturers estimated credit 
balances, planned credit flexibilities (i.e., credit balances, planned 
credit trading, innovative, advanced and early credits and etc.) and if 
needed a credit deficit plan demonstrating how it plans to resolve any 
credit deficits that might occur for a model year within a period of up 
to three model years after that deficit has occurred; and
    (xiii) The supplemental information specified in paragraph (h) of 
this section. [Note: NHTSA may also ask a manufacturer to provide 
additional information if necessary to verify compliance with the fuel 
consumption requirements of this regulation.]
    (c) Applications for certificate of conformity. Manufacturers 
producing vocational vehicles, tractors and heavy-duty engines are 
required to submit applications for certificates of conformity to EPA 
in accordance with 40 CFR 1036.205 and 1037.205 in advance of 
introducing vehicles for commercial sale. Applications contain early 
model year information demonstrating how manufacturers plan to comply 
with GHG emissions. For model years 2013 and later, manufacturers of 
vocational vehicles, tractors and engine complying with NHTSA's 
voluntary and mandatory standards must submit applications for 
certificates of conformity in accordance through the EPA database 
including both GHG emissions and fuel consumption information for each 
given model year.
    (1) Submission deadlines. Applications are primarily submitted in 
advance of the given model year to EPA but cannot be submitted any 
later than December 31 of the given model year.
    (2) Contents. Each application for certificates of conformity 
submitted to EPA must include the following equivalent fuel 
consumption.
    (i) Equivalent fuel consumption values for emissions CO2 
FCLs values used to certify each engine family in accordance with 40 
CFR 1036.205(e). This provision applies only to manufacturers producing 
heavy-duty engines.
    (ii) Equivalent fuel consumption values for emission CO2 
data engines used to comply with emission standards in 40 CFR 1036.108. 
This provision applies only to manufacturers producing heavy-duty 
engines.
    (iii) Equivalent fuel consumption values for emissions 
CO2 FELs values used to certify each vehicle families or 
subfamilies in accordance with 40 CFR 1037.205(k). This provision 
applies only to manufacturers producing vocational vehicles and 
tractors.
    (iv) Report modeling results for ten configurations in terms of 
CO2 emissions and equivalent fuel consumption results in 
accordance with 40 CFR 1037.205(o). Include modeling inputs and 
detailed descriptions of how they were derived. This provision applies 
only to manufacturers producing vocational vehicles and tractors.
    (3) Additional supplemental information. Manufacturers are required 
to submit additional information as specified in paragraph (h) of this 
section for the NHTSA program before or at the same time it submits its 
first application for a certificate of conformity to EPA. Under limited 
conditions, NHTSA may also ask a manufacturer to provide additional 
information directly to the Administrator if necessary to verify the 
fuel consumption requirements of this regulation.
    (d) End-of-the-year-report. Both manufacturers participating and 
not participating in the ABT program are required to submit year end 
reports; end-of-the-year (EOY) reports in accordance with 40 CFR 
1036.730 and 1037.730. The EOY reports are used to review a 
manufacturer's preliminary final estimates and to identify 
manufacturers that might have a credit deficit for the given model 
year. For model years 2013 and later, heavy-duty vehicle and engine 
manufacturers complying with NHTSA's voluntary and mandatory standards 
must submit EOY reports through the EPA database including both GHG 
emissions and fuel consumption information for each given model year.
    (1) Report deadlines. For model year 2013 and later, heavy-duty 
vehicle and engine manufacturers complying with NHTSA voluntary and 
mandatory standards must submit EOY reports through the EPA database 
including both GHG emissions and fuel consumption information within 90 
days after the end of the given model year and no later than April 1 of 
the next calendar year. For example, the EOY report for model year 2014 
must be submitted no later than April 1, 2015.
    (i) If a manufacturer expects differences in the information 
reported between the EOY and the final year report specified in 40 CFR 
1036.730 and 1037.730, it must provide the most up-to-date fuel 
consumption projections in its EOY report and indentify the information 
as preliminary.
    (ii) If the manufacturer cannot provide any of the required fuel 
consumption information, it must state the specific reason for the 
insufficiency and identify the additional testing needed or explain 
what analytical methods are believed by the manufacturer will be 
necessary to eliminate the insufficiency and certify that the results 
will be available for the final report.
    (2) Contents. Each EOY report must be submitted including the 
following fuel consumption information for each model year.
    (i) Engine and vehicle family designations and averaging sets.
    (ii) Engine and vehicle regulatory subcategory and fuel consumption 
standards including any alternative standards used.
    (iii) Engine and vehicle family FCLs and FELs in terms of fuel 
consumption.
    (iv) Production volumes for engines and vehicles.
    (v) A credit plan (for manufacturers participating in the ABT 
program) identifying the manufacturers actual fuel consumption credit 
balances, credit flexibilities, credit trades and a credit deficit plan 
if needed demonstrating how it plans to resolve any credit

[[Page 57509]]

deficits that might occur for a model year within a period of up to 
three model years after that deficit has occurred
    (vi) A plan describing the vocational vehicles and vocational 
tractors that were exempted as heavy-duty off-road vehicles.
    (vii) A final plan describing any advanced technology engines or 
vehicles including alternative fueled vehicles that were produced for 
the model year identifying the approaches used to determinate 
compliance and the production volumes.
    (viii) A final list of each unique subconfiguration included in a 
manufacturers fleet of heavy-duty pickup trucks and vans describing the 
designations, attribute based-values (GVWR, GCWR, Curb Weight and drive 
configurations) and standards. This provision applies only to 
manufacturers producing heavy-duty pickup trucks and vans.
    (ix) The final fuel consumption fleet average standard derived from 
the unique vehicle configurations. This provision applies only to 
manufacturers producing heavy-duty pickup trucks and vans.
    (x) The preliminary final subconfiguration and test group 
production volumes. This provision applies only to manufacturers 
producing heavy-duty pickup trucks and vans.
    (xi) The preliminary final fuel consumption test group results and 
fleet average performance. This provision applies only to manufacturers 
producing heavy-duty pickup trucks and vans.
    (xii) Under limited conditions, NHTSA may also ask a manufacturer 
to provide additional information directly to the Administrator if 
necessary to verify the fuel consumption requirements of this part.
    (e) Final reports. Both manufacturers participating and not 
participating in the ABT program are required to submit year end final 
reports in accordance with 40 CFR 1036.730 and 1037.730. The final 
reports are used to review a manufacturer's final data and to identify 
manufacturers that might have a credit deficit for the given model 
year. For model years 2013 and later, heavy-duty vehicle and engine 
manufacturers complying with NHTSA's voluntary and mandatory standards 
must submit final reports through the EPA database including both GHG 
emissions and fuel consumption information for each given model year.
    (1) Report deadlines. For model year 2013 and later, heavy-duty 
vehicle and engine manufacturers complying with NHTSA voluntary and 
mandatory standards must submit final reports through the EPA database 
including both GHG emissions and fuel consumption information within 
270 days after the end of the given model year and no later than 
October 1 of the next calendar year. For example, the final reports for 
model year 2014 must be submitted no later than October 1, 2015.
    (2) Contents. Each final report must be submitted including the 
following fuel consumption information for each model year.
    (i) Final engine and vehicle family designations and averaging 
sets.
    (ii) Final engine and vehicle fuel consumption standards including 
any alternative standards used.
    (iii) Final engine and vehicle family FCLs and FELs in terms of 
fuel consumption.
    (iv) Final production volumes for engines and vehicles.
    (v) A final credit plan identifying the manufacturers actual fuel 
consumption credit balances, credit flexibilities, credit trades and a 
credit deficit plan if needed demonstrating how it plans to resolve any 
credit deficits that might occur for a model year within a period of up 
to three model years after that deficit has occurred
    (vi) A final plan describing the vocational vehicles and vocational 
tractors that were exempted as heavy-duty off-road vehicles.
    (vii) A final plan describing any advanced technology engines or 
vehicles including alternative fueled vehicles that were produced for 
the model year identifying the approaches used to determinate 
compliance and the production volumes.
    (viii) A final list of each unique subconfiguration included in a 
manufacturers fleet of heavy-duty pickup trucks and vans describing the 
designations, attribute based-values (GVWR, GCWR, Curb Weight and drive 
configurations) and standards. This provision applies only to 
manufacturers producing heavy-duty pickup trucks and vans.
    (ix) The final fuel consumption fleet average standard derived from 
the unique vehicle configurations. This provision applies only to 
manufacturers producing heavy-duty pickup trucks and vans.
    (x) The final subconfiguration and test group production volumes. 
This provision applies only to manufacturers producing heavy-duty 
pickup trucks and vans.
    (xi) The final fuel consumption test group results and fleet 
average performance. This provision applies only to manufacturers 
producing heavy-duty pickup trucks and vans.
    (xii) Under limited conditions, NHTSA may also ask a manufacturer 
to provide additional information directly to the Administrator if 
necessary to verify the fuel consumption requirements of this 
regulation.
    (f) Amendments to applications for certification. At any time, a 
manufacturer modifies an application for certification in accordance 
with 40 CFR 1036.225 and 1037.225, it must submit GHG emissions changes 
with equivalent fuel consumption values for the information required in 
paragraphs (b) through (e) and (h) of this section.
    (g) Confidential information. Manufacturers must submit a request 
for confidentiality with each electronic submission specifying any part 
of the for information or data in a report that it believes should be 
withheld from public disclosure as trade secret or other confidential 
business information. Information submitted to EPA should follow EPA 
guidelines for treatment of confidentiality. Confidential information 
submitted to NHTSA shall be treated according to paragraph (g)(1) of 
this section. For any information or data requested by the manufacturer 
to be withheld under 5 U.S.C. 552(b)(4) and 15 U.S.C. 2005(d)(1), the 
manufacturer shall provide evidence in its request for confidentiality 
to justify that:
    (1) The item is within the scope of 5 U.S.C. 552(b)(4) and 15 
U.S.C. 2005(d)(1);
    (2) The disclosure of such an item would result in significant 
competitive damage;
    (3) The period during which the item must be withheld to avoid that 
damage; and
    (4) How earlier disclosure would result in that damage.
    (h) Additional required information. The following additional 
information is required to be submitted through the EPA database. NHTSA 
reserves the right to ask a manufacturer to provide additional 
information if necessary to verify the fuel consumption requirements of 
this regulation.
    (1) Small business exemptions. Vehicles and engines produced by 
small business manufacturers meeting the criteria in 13 CFR 121.201 are 
exempted from the requirements of this part. Qualifying small business 
manufacturers must notify the EPA and NHTSA Administrators before 
importing or introducing into U.S. commerce exempted vehicles or 
engines. This notification must include a description of the 
manufacturer's qualification as a small business under

[[Page 57510]]

13 CFR 121.201 and must be submitted to EPA. The agencies may review a 
manufacturer's qualification as a small business manufacturer under 13 
CFR 121.201.
    (2) Early introduction. The provision applies to manufacturers 
seeking to comply early with the NHTSA's fuel consumption program prior 
to model year 2014. The manufacturer must send the request to EPA 
before submitting its first application for a certificate of 
conformity.
    (3) NHTSA voluntary compliance model years. Manufacturers must 
submit a statement declaring whether the manufacturer chooses to comply 
voluntarily with NHTSA's fuel consumption standards for model years 
2014 through 2015. The manufacturers must acknowledge that once 
selected, the decision cannot be reversed and the manufacturer will 
continue to comply with the fuel consumption standards for subsequent 
model years. The manufacturer must send the statement to EPA before 
submitting its first application for a certificate of conformity.
    (4) Alternative engine standards. Manufacturers choosing to comply 
with the alternative engine standards must notify EPA and NHTSA of 
their choice and include in that notification a demonstration that it 
has exhausted all available credits and credit opportunities. The 
manufacturer must send the statement to EPA before submitting its EOY 
report.
    (5) Alternate phase-in. Manufacturers choosing to comply with the 
alternative engine phase-in must notify EPA and NHTSA of their choice. 
The manufacturer must send the statement to EPA before submitting its 
first application for a certificate of conformity.
    (6) Off-road exclusion (tractors and vocational vehicles only). (i) 
Vehicles intended to be used extensively in off-road environments such 
as forests, oil fields, and construction sites may be exempted without 
request from the requirements of this regulation as specified in 49 CFR 
523.2 and Sec.  535.5(b). Within 90 days after the end of each model 
year, manufacturers must send EPA and NHTSA through the EPA database a 
report with the following information:
    (A) A description of each excluded vehicle configuration, including 
an explanation of why it qualifies for this exclusion.
    (B) The number of vehicles excluded for each vehicle configuration.
    (ii) A manufacturer having an off-road vehicle failing to meet the 
criteria under the agencies' off-road exclusions will be allowed to 
submit a petition describing how and why their vehicles should qualify 
for exclusion. The process of petitioning for an exclusion is explained 
below. For each request, the manufacturer will be required to describe 
why it believes an exclusion is warranted and address the following 
factors which the agencies will consider in granting its petition:
    (A) The agencies will provide an exclusion based on off road 
capability of the vehicle or if the vehicle is fitted with speed 
restricted tires. A manufacturer should explain which exclusion does 
its vehicle qualify under; and
    (B) A manufacturer should verify if there are any comparable tires 
that exist in the market to carry out the desired application both on 
and off road for the subject vehicle(s) of the petition which have LLR 
values that would enable compliance with the standard.
    (7) Vocational tractor. Tractors intended to be used as vocational 
tractors may comply with vocational vehicle standards in Sec.  535.5(b) 
of this regulation. Manufacturers classifying tractor as vocational 
tractors must provide a description of how they meet the qualifications 
in their applications for certificates of conformity as specified in 40 
CFR 1037.205.
    (8) Approval of alternate methods to determine drag coefficients 
(tractors only). Manufacturers seeking to use alternative methods to 
determine aerodynamic drag coefficients must provide a request and gain 
approval by EPA. The manufacturer must send the request to EPA before 
submitting its first application for a certificate of conformity.
    (9) Innovative technology credits. Manufacturers pursuing 
innovative technology credits must submit information to the agencies 
and may be subject to a public evaluation process in which the public 
would have opportunity for comment if not using a test procedure in 
accordance with 40 CFR 1037.610(c). Whether the approach involves on-
road testing, modeling, or some other analytical approach, the 
manufacturer would be required to present a final methodology to EPA 
and NHTSA. EPA and NHTSA would approve the methodology and credits only 
if certain criteria were met. Baseline emissions and fuel consumption 
and control emissions and fuel consumption would need to be clearly 
demonstrated over a wide range of real world driving conditions and 
over a sufficient number of vehicles to address issues of uncertainty 
with the data. Data would need to be on a vehicle model-specific basis 
unless a manufacturer demonstrated model-specific data was not 
necessary. The agencies may publish a notice of availability in the 
Federal Register notifying the public of a manufacturer's proposed 
alternative off-cycle credit calculation methodology and provide 
opportunity for comment. Any notice will include details regarding the 
methodology, but not include any Confidential Business Information.
    (10) Credit trades. If a manufacturer trades fuel consumption 
credits, it must send EPA a report within 90 days after the 
transaction, as follows:
    (i) As the seller, the manufacturer must include the following 
information in its report:
    (A) The corporate names of the buyer and any brokers.
    (B) A copy of any contracts related to the trade.
    (C) The fleet, vehicle or engine families that generated fuel 
consumption credits for the trade, including the number of fuel 
consumption credits from each family.
    (ii) As the buyer, the manufacturer or entity must include the 
following information in its report:
    (A) The corporate names of the seller and any brokers.
    (B) A copy of any contracts related to the trade.
    (C) How the manufacturer or entity intends to use the fuel 
consumption credits, including the number of fuel consumption credits 
it intends to apply to each vehicle family (if known).
    (i) Public information. Based upon information submitted by 
manufacturers and EPA, NHTSA will publish fuel consumption standards 
and performance results.
    (j) Information received from EPA. NHTSA will receive information 
from EPA as specified in 40 CFR 1036.755 and 1037.755.

Sec.  535.9  Enforcement approach.

    (a) Compliance. (1) NHTSA will assess compliance with fuel 
consumption standards each year, based upon EPA final verified data 
submitted to NHTSA for its heavy-duty vehicle fuel efficiency program 
established pursuant to 49 U.S.C. 32902(k). NHTSA may conduct 
verification testing throughout a given model year in order to validate 
data received from manufacturers and will discuss any potential issues 
with EPA and the manufacturer.
    (2) Credit values in gallons are calculated based on the final 
CO2 emissions and fuel consumption data submitted by 
manufacturers and verified/validated by EPA.
    (3) NHTSA will verify a manufacturer's credit balance in each

[[Page 57511]]

averaging set for each given model year. The average set balance is 
based upon the engines or vehicles performance above or below the 
applicable regulatory subcategory standards in each respective 
averaging set and any credits that are traded into or out of an 
averaging set during the model year.
    (i) If the balance is positive, the manufacturer is designated as 
having a credit surplus.
    (ii) If the balance is negative, the manufacturer is designated as 
having a credit deficit.
    (4) NHTSA will provide written notification to the manufacturer 
that has a negative balance for any averaging set for each model year. 
The manufacturer will be required to confirm the negative balance and 
submit a plan indicating how it will allocate existing credits or earn, 
and/or acquire by trade credits, or else be liable for a civil penalty 
as determined in paragraph (b) of this section. The manufacturer must 
submit a plan within 60 days of receiving agency notification.
    (5) Credit shortfall within an averaging set may be carried forward 
only three years, and if not offset by earned or traded credits, the 
manufacturer may be liable for a civil penalty as described in 
paragraph (b) of this section.
    (6) Credit allocation plans received from a manufacturer will be 
reviewed and approved by NHTSA. NHTSA will approve a credit allocation 
plan unless it determines that the proposed credits are unavailable or 
that it is unlikely that the plan will result in the manufacturer 
earning sufficient credits to offset the subject credit shortfall. If a 
plan is approved, NHTSA will revise the respective manufacturer's 
credit account accordingly by identifying which existing or traded 
credits are being used to address the credit shortfall, or by 
identifying the manufacturer's plan to earn future credits for 
addressing the respective credit shortfall. If a plan is rejected, 
NHTSA will notify the respective manufacturer and request a revised 
plan. The manufacturer must submit a revised plan within 14 days of 
receiving agency notification. The agency will provide a manufacturer 
one opportunity to submit a revised credit allocation plan before it 
initiates civil penalty proceedings.
    (7) For purposes of this regulation, NHTSA will treat the use of 
future credits for compliance, as through a credit allocation plan, as 
a deferral of civil penalties for non-compliance with an applicable 
fuel consumption standard.
    (8) If NHTSA receives and approves a manufacturer's credit 
allocation plan to earn future credits within the following three model 
years in order to comply with regulatory obligations, NHTSA will defer 
levying civil penalties for non-compliance until the date(s) when the 
manufacturer's approved plan indicates that credits will be earned or 
acquired to achieve compliance, and upon receiving confirmed 
CO2 emissions and fuel consumption data from EPA. If the 
manufacturer fails to acquire or earn sufficient credits by the plan 
dates, NHTSA will initiate civil penalty proceedings.
    (9) In the event that NHTSA fails to receive or is unable to 
approve a plan for a non-compliant manufacturer due to insufficiency or 
untimeliness, NHTSA may initiate civil penalty proceedings.
    (10) In the event that a manufacturer fails to report accurate fuel 
consumption data for vehicles or engines covered under this rule, 
noncompliance will be assumed until corrected by submission of the 
required data, and NHTSA may initiate civil penalty proceedings.
    (b) Civil penalties. (1) Generally. NHTSA may assess a civil 
penalty for any violation of this part under 49 U.S.C. 32902(k). This 
section states the procedures for assessing civil penalties for 
violations of Sec.  535.5. The provisions of 5 U.S.C. 554, 556, and 557 
do not apply to any proceedings conducted pursuant to this section.
    (2) Initial determination of noncompliance. An action for civil 
penalties is commenced by the execution of a Notice of Violation. A 
determination by NHTSA's Office of Enforcement of noncompliance with 
applicable fuel consumption standards utilizing the certified and 
reported CO2 emissions and fuel consumption data provided by 
the Environmental Protection Agency as described in this part, and 
after considering all the flexibilities available under Sec.  535.7, 
underlies a Notice of Violation. If NHTSA Enforcement determines that a 
manufacturer's averaging set of vehicles or engines fails to comply 
with the applicable fuel consumption standard(s) by generating a credit 
shortfall, the chassis, vehicle or engine manufacturer, as relevant, 
shall be subject to a civil penalty.
    (3) Numbers of violations and maximum civil penalties. Any 
violation shall constitute a separate violation with respect to each 
vehicle or engine within the applicable regulatory averaging set. The 
maximum civil penalty is not more than $37,500.00 per vehicle or 
engine. The maximum civil penalty under this section for a related 
series of violations shall be determined by multiplying $37,500.00 
times the vehicle or engine production volume for the model year in 
question within the regulatory averaging set. NHTSA may adjust this 
civil penalty amount to account for inflation.
    (4) Factors for determining penalty amount. In determining the 
amount of any civil penalty proposed to be assessed or assessed under 
this section, NHTSA shall take into account the gravity of the 
violation, the size of the violator's business, the violator's history 
of compliance with applicable fuel consumption standards, the actual 
fuel consumption performance related to the applicable standards, the 
estimated cost to comply with the regulation and applicable standards, 
the quantity of vehicles or engines not complying, and the effect of 
the penalty on the violator's ability to continue in business. The 
``estimated cost to comply with the regulation and applicable 
standards,'' will be used to ensure that penalties for non-compliance 
will not be less than the cost of compliance.
    (5) NHTSA enforcement report of determination of non-compliance. 
(i) If NHTSA Enforcement determines that a violation has occurred, 
NHTSA Enforcement may prepare a report and send the report to the NHTSA 
Chief Counsel.
    (ii) The NHTSA Chief Counsel will review the report prepared by 
NHTSA Enforcement to determine if there is sufficient information to 
establish a likely violation.
    (iii) If the Chief Counsel determines that a violation has likely 
occurred, the Chief Counsel may issue a Notice of Violation to the 
party.
    (iv) If the Chief Counsel issues a Notice of Violation, he or she 
will prepare a case file with recommended actions. A record of any 
prior violations by the same party shall be forwarded with the case 
file.
    (6) Notice of violation. (i) The Notice of Violation will contain 
the following information:
    (A) The name and address of the party;
    (B) The alleged violation(s) and the applicable fuel consumption 
standard(s) violated;
    (C) The amount of the proposed penalty and basis for that amount;
    (D) The place to which, and the manner in which, payment is to be 
made;
    (E) A statement that the party may decline the Notice of Violation 
and that if the Notice of Violation is declined within 30 days of the 
date shown on the Notice of Violation, the party has the right to a 
hearing, if requested within 30 days of the date shown on the Notice of

[[Page 57512]]

Violation, prior to a final assessment of a penalty by a Hearing 
Officer; and
    (F) A statement that failure to either pay the proposed penalty or 
to decline the Notice of Violation and request a hearing within 30 days 
of the date shown on the Notice of Violation will result in a finding 
of violation by default and that NHTSA will proceed with the civil 
penalty in the amount proposed on the Notice of Violation without 
processing the violation under the hearing procedures set forth in this 
subpart.
    (ii) The Notice of Violation may be delivered to the party by:
    (A) Mailing to the party (certified mail is not required);
    (B) Use of an overnight or express courier service; or
    (C) Facsimile transmission or electronic mail (with or without 
attachments) to the party or an employee of the party.
    (iii) At any time after the Notice of Violation is issued, NHTSA 
and the party may agree to reach a compromise on the payment amount.
    (iv) Once a penalty amount is paid in full, a finding of ``resolved 
with payment'' will be entered into the case file.
    (v) If the party agrees to pay the proposed penalty, but has not 
made payment within 30 days of the date shown on the Notice of 
Violation, NHTSA will enter a finding of violation by default in the 
matter and NHTSA will proceed with the civil penalty in the amount 
proposed on the Notice of Violation without processing the violation 
under the hearing procedures set forth in this subpart.
    (vi) If within 30 days of the date shown on the Notice of Violation 
a party fails to pay the proposed penalty on the Notice of Violation, 
and fails to request a hearing, then NHTSA will enter a finding of 
violation by default in the case file, and will assess the civil 
penalty in the amount set forth on the Notice of Violation without 
processing the violation under the hearing procedures set forth in this 
subpart.
    (vii) NHTSA's order assessing the civil penalty following a party's 
default is a final agency action.
    (7) Hearing Officer. (i) If a party timely requests a hearing after 
receiving a Notice of Violation, a Hearing Officer shall hear the case.
    (ii) The Hearing Officer will be appointed by the NHTSA 
Administrator, and is solely responsible for the case referred to him 
or her. The Hearing Officer shall have no other responsibility, direct 
or supervisory, for the investigation of cases referred for the 
assessment of civil penalties. The Hearing Officer shall have no duties 
related to the light-duty fuel economy or medium- and heavy-duty fuel 
efficiency programs.
    (iii) The Hearing Officer decides each case on the basis of the 
information before him or her.
    (8) Initiation of action before the Hearing Officer. (i) After the 
Hearing Officer receives the case file from the Chief Counsel, the 
Hearing Officer notifies the party in writing of:
    (A) The date, time, and location of the hearing and whether the 
hearing will be conducted telephonically or at the DOT Headquarters 
building in Washington, DC;
    (B) The right to be represented at all stages of the proceeding by 
counsel as set forth in paragraph (b)(9) of this section;
    (C) The right to a free copy of all written evidence in the case 
file.
    (ii) On the request of a party, or at the Hearing Officer's 
direction, multiple proceedings may be consolidated if at any time it 
appears that such consolidation is necessary or desirable.
    (9) Counsel. A party has the right to be represented at all stages 
of the proceeding by counsel. A party electing to be represented by 
counsel must notify the Hearing Officer of this election in writing, 
after which point the Hearing Officer will direct all further 
communications to that counsel. A party represented by counsel bears 
all of its own attorneys' fees and costs.
    (10) Hearing location and costs. (i) Unless the party requests a 
hearing at which the party appears before the Hearing Officer in 
Washington, DC, the hearing may be held telephonically. In Washington, 
DC, the hearing is held at the headquarters of the U.S. Department of 
Transportation.
    (ii) The Hearing Officer may transfer a case to another Hearing 
Officer at a party's request or at the Hearing Officer's direction.
    (iii) A party is responsible for all fees and costs (including 
attorneys' fees and costs, and costs that may be associated with travel 
or accommodations) associated with attending a hearing.
    (11) Hearing procedures. (i) There is no right to discovery in any 
proceedings conducted pursuant to this subpart.
    (ii) The material in the case file pertinent to the issues to be 
determined by the Hearing Officer is presented by the Chief Counsel or 
his or her designee.
    (iii) The Chief Counsel may supplement the case file with 
information prior to the hearing. A copy of such information will be 
provided to the party no later than 3 business days before the hearing.
    (iv) At the close of the Chief Counsel's presentation of evidence, 
the party has the right to examine respond to and rebut material in the 
case file and other information presented by the Chief Counsel. In the 
case of witness testimony, both parties have the right of cross-
examination.
    (v) In receiving evidence, the Hearing Officer is not bound by 
strict rules of evidence. In evaluating the evidence presented, the 
Hearing Officer must give due consideration to the reliability and 
relevance of each item of evidence.
    (vi) At the close of the party's presentation of evidence, the 
Hearing Officer may allow the introduction of rebuttal evidence that 
may be presented by the Chief Counsel.
    (vii) The Hearing Officer may allow the party to respond to any 
rebuttal evidence submitted.
    (viii) After the evidence in the case has been presented, the Chief 
Counsel and the party may present arguments on the issues in the case. 
The party may also request an opportunity to submit a written statement 
for consideration by the Hearing Officer and for further review. If 
granted, the Hearing Officer shall allow a reasonable time for 
submission of the statement and shall specify the date by which it must 
be received. If the statement is not received within the time 
prescribed, or within the limits of any extension of time granted by 
the Hearing Officer, it need not be considered by the Hearing Officer.
    (ix) A verbatim transcript of the hearing will not normally be 
prepared. A party may, solely at its own expense, cause a verbatim 
transcript to be made. If a verbatim transcript is made, the party 
shall submit two copies to the Hearing Officer not later than 15 days 
after the hearing. The Hearing Officer shall include such transcript in 
the record.
    (12) Determination of violations and assessment of civil penalties. 
(i) Not later than 30 days following the close of the hearing, the 
Hearing Officer shall issue a written decision on the Notice of 
Violation, based on the hearing record. This may be extended by the 
Hearing officer if the submissions by the Chief Counsel or the party 
are voluminous. The decision shall address each alleged violation, and 
may do so collectively. For each alleged violation, the decision shall 
find a violation or no violation and provide a basis for the finding. 
The decision shall set forth the basis for the Hearing Officer's 
assessment of a civil penalty, or decision not to assess a civil 
penalty. In determining the amount of the civil penalty, the gravity of 
the violation, the size of the violator's

[[Page 57513]]

business, the violator's history of compliance with applicable fuel 
consumption standards, the actual fuel consumption performance related 
to the applicable standard, the estimated cost to comply with the 
regulation and applicable standard, the quantity of vehicles or engines 
not complying, and the effect of the penalty on the violator's ability 
to continue in business. The assessment of a civil penalty by the 
Hearing Officer shall be set forth in an accompanying final order. The 
Hearing Officer's written final order is a final agency action.
    (ii) If the Hearing Officer assesses civil penalties in excess of 
$1,000,000, the Hearing Officer's decision shall contain a statement 
advising the party of the right to an administrative appeal to the 
Administrator within a specified period of time. The party is advised 
that failure to submit an appeal within the prescribed time will bar 
its consideration and that failure to appeal on the basis of a 
particular issue will constitute a waiver of that issue in its appeal 
before the Administrator.
    (iii) The filing of a timely and complete appeal to the 
Administrator of a Hearing Officer's order assessing a civil penalty 
shall suspend the operation of the Hearing Officer's penalty, which 
shall no longer be a final agency action.
    (iv) There shall be no administrative appeals of civil penalties 
assessed by a Hearing Officer of less than $1,000,000.
    (13) Appeals of civil penalties in excess of $1,000,000. (i) A 
party may appeal the Hearing Officer's order assessing civil penalties 
over $1,000,000 to the Administrator within 21 days of the date of the 
issuance of the Hearing Officer's order.
    (ii) The Administrator will review the decision of the Hearing 
Officer de novo, and may affirm the decision of the hearing officer and 
assess a civil penalty, or
    (iii) The Administrator may:
    (A) Modify a civil penalty;
    (B) Rescind the Notice of Violation; or
    (C) Remand the case back to the Hearing Officer for new or 
additional proceedings.
    (iv) In the absence of a remand, the decision of the Administrator 
in an appeal is a final agency action.
    (14) Collection of assessed or compromised civil penalties. (i) 
Payment of a civil penalty, whether assessed or compromised, shall be 
made by check, postal money order, or electronic transfer of funds, as 
provided in instructions by the agency. A payment of civil penalties 
shall not be considered a request for a hearing.
    (ii) The party must remit payment of any assessed civil penalty to 
NHTSA within 30 days after receipt of the Hearing Officer's order 
assessing civil penalties, or, in the case of an appeal to the 
Administrator, within 30 days after receipt of the Administrator's 
decision on the appeal.
    (iii) The party must remit payment of any compromised civil penalty 
to NHTSA on the date and under such terms and conditions as agreed to 
by the party and NHTSA. Failure to pay may result in NHTSA entering a 
finding of violation by default and assessing a civil penalty in the 
amount proposed in the Notice of Violation without processing the 
violation under the hearing procedures set forth in this part.
    (c) Changes in corporate ownership and control. Manufacturers must 
inform NHTSA of corporate relationship changes to ensure that credit 
accounts are identified correctly and credits are assigned and 
allocated properly.
    (1) In general, if two manufacturers merge in any way, they must 
inform NHTSA how they plan to merge their credit accounts. NHTSA will 
subsequently assess corporate fuel consumption and compliance status of 
the merged fleet instead of the original separate fleets.
    (2) If a manufacturer divides or divests itself of a portion of its 
automobile manufacturing business, it must inform NHTSA how it plans to 
divide the manufacturer's credit holdings into two or more accounts. 
NHTSA will subsequently distribute holdings as directed by the 
manufacturer, subject to provision for reasonably anticipated 
compliance obligations.
    (3) If a manufacturer is a successor to another manufacturer's 
business, it must inform NHTSA how it plans to allocate credits and 
resolve liabilities per 49 CFR part 534.

    Dated: August 9, 2011.
Ray LaHood,
Secretary, Department of Transportation.
    Dated: August 9, 2011.
Lisa P. Jackson,
Administrator, Environmental Protection Agency.
[FR Doc. 2011-20740 Filed 9-14-11; 8:45 am]
BILLING CODE 4910-59-P
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