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EO12866_HD_NR_Technical_Amendment_2060-AR48_NPRM_20130508.docx 

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 85, 86, 1036, 1037, 1039, 1042, 1048, 1054, 1065, 1066, 1068

[EPA-HQ-OAR-2012-0102]

RIN 2060-AR48

Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of proposed rulemaking.

SUMMARY: EPA is proposing to amend provisions in the Medium- and Heavy-Duty 

Greenhouse Gas Emissions and Fuel Efficiency final rule issued on September 15, 2011 

(76 FR 57106). These proposed amendments would eliminate duplicative reporting 

requirements, reduce inadvertent minor differences between the EPA and NHTSA 

programs regarding such matters as voluntary early model year compliance, better align 

testing procedures to market realities, and reduce unnecessary testing burdens. EPA is 

also proposing to amend several regulations by: (1) adjusting the provisions of the 

replacement engine exemption, (2) expanding EPA’s discretion to allow greater 

flexibility under the Transition Program for Equipment Manufacturers related to the Tier 

4 standards for nonroad diesel engines, (3) specifying multiple versions of the applicable 

SAE standard for demonstrating that fuel lines for nonroad spark-ignition engines above 

19 kilowatts meet permeation requirements, and (4) allowing for the use of the ethanolbased test fuel specified by the California Air Resources Board for nonroad sparkignition engines at or below 19 kilowatts. Some of the individual provisions of this 

action may have minor impacts on the costs and emission reductions of the underlying 
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regulatory programs amended in this action, though in most cases these are simple 

technical amendments. For those provisions that may have a minor impact on the costs 

or benefits of the amended regulatory program, any potential impacts would be small and 

we have not attempted to quantify the potential changes.

DATES: Comments on all aspects of this proposal must be received on or before [insert 

date 30 days after publication in the FEDERAL REGISTER]. See the 

SUPPLEMENTARY INFORMATION section on “Public Participation” for more 

information about written comments.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OAR2012-0102, by one of the following methods:

www.regulations.gov: Follow the on-line instructions for submitting comments.

Email: a-and-r-docket@epa.gov

Fax: (202) 566-9744

Mail: Air and Radiation Docket and Information Center, Environmental Protection 

Agency, Air Docket, Mail-code 28221T, 1200 Pennsylvania Ave., NW, Washington, 

DC 20460. 

Hand Delivery: EPA Docket Center (EPA/DC), EPA West, Room 3334, 1301 

Constitution Ave., NW, Washington, DC, Attention Docket ID No. EPA-HQ- OAR2012-0102. Such deliveries are only accepted during the Docket’s normal hours of 

operation, and special arrangements should be made for deliveries of boxed 

information.
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Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-2012-0102. See 

the SUPPLEMENTARY INFORMATION section on “Public Participation” for 

additional instructions on submitting written comments.

Docket: All documents in the docket are listed in the www.regulations.gov index. 

Although listed in the index, some information is not publicly available, e.g., information 

claimed as Confidential Business Information (CBI) or other information whose 

disclosure is restricted by statute. Certain other material, such as copyrighted material, 

will be publicly available only in hard copy. Publicly available docket materials are 

available either electronically in www.regulations.gov or in hard copy at the 

EPA Docket Center, EPA/DC, EPA West, Room 3334, 1301 Constitution Ave., NW, 

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.

FOR FURTHER INFORMATION CONTACT: Angela Cullen, Environmental 

Protection Agency, Office of Transportation and Air Quality, Assessment and Standards 

Division, 2000 Traverwood Drive, Ann Arbor, Michigan 48105; telephone number: 734-

214-4419; email address: cullen.angela@epa.gov.

I. SUPPLEMENTARY INFORMATION

A. Does This Action Apply to Me?

This proposed action would affect companies that manufacture, sell, or import 

into the United States new heavy-duty engines and new Class 2b through 8 vehicles, 

including combination tractors, school and transit buses, vocational vehicles such as 
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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 (75 

FR at 25324, May 7, 2010). 

This proposed action also would affect nonroad engine manufacturers.

Regulated categories and entities would include the following: 

Category NAICS CodeaExamples of Potentially Affected Entities

Industry 336111 Motor Vehicle Manufacturers, Engine and 

336112 Truck Manufacturers

333618

336120

Industry 541514 Commercial Importers of Vehicles and 

811112 Vehicle Components

811198

Industry 336111 Alternative Fuel Vehicle Converters

336112

422720

454312

541514

541690

811198

336510

Industry 811310 Engine Repair, Remanufacture, and 

Maintenance

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 this proposed rule. This table lists the types of 

entities that the agency is aware may be regulated by this proposed action. Other types of 
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entities not listed in the table could also be regulated. To determine whether your 

activities would be regulated by this proposed action, you should carefully examine the 

applicability criteria in the referenced regulations. You may direct questions regarding 

the applicability of this proposed action to the person listed in the preceding FOR 

FURTHER INFORMATION CONTACT section.

B. What Should I Consider as I Prepare My Comments?

Direct your comments to Docket ID No. EPA-HQ-OAR-2012-0102. EPA’s 

policy is that all comments received will be included in the public docket without change 

and may be made available online at www.regulations.gov, including any personal 

information provided, unless the comment includes information claimed to be 

Confidential Business Information (CBI) or other information whose disclosure is 

restricted by statute. Do not submit information that you consider to be CBI or otherwise 

protected through www.regulations.gov or e-mail. The www.regulations.gov website is 

an “anonymous access” system, which means EPA will not know your identity or contact 

information unless you provide it in the body of your comment. If you send an e-mail 

comment directly to EPA without going through www.regulations.gov your e-mail 

address will be automatically captured and included as part of the comment that is placed 

in the public docket and made available on the Internet. If you submit an electronic 

comment, EPA recommends that you include your name and other contact information in 

the body of your comment and with any disk or CD-ROM you submit. If EPA cannot 

read your comment due to technical difficulties and cannot contact you for clarification, 

EPA may not be able to consider your comment. Electronic files should avoid the use of 

special characters, any form of encryption, and be free of any defects or viruses. For 
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additional information about EPA’s public docket visit the EPA Docket Center homepage 

at http://www.epa.gov/epahome/dockets.htm. 

(1) Tips for Preparing Your Comments 

When submitting comments, remember to:

Identify the rulemaking by docket number and other identifying information (subject 

heading, Federal Register date and page number).

Follow directions - The agency may ask you to respond to specific questions or 

organize comments by referencing a Code of Federal Regulations (CFR) part or 

section number.

Explain why you agree or disagree, suggest alternatives, and substitute language for 

your requested changes.

Describe any assumptions and provide any technical information and/or data that you 

used.

If you estimate potential costs or burdens, explain how you arrived at your estimate in 

sufficient detail to allow for it to be reproduced.

Provide specific examples to illustrate your concerns, and suggest alternatives.

Explain your views as clearly as possible, avoiding the use of profanity or personal 

threats.

Make sure to submit your comments by the comment period deadline identified in the 

DATES section above.
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(2) How Do I Submit Confidential Business Information?

Do not submit CBI to EPA through www.regulations.gov or e-mail. Clearly mark 

the part or all of the information that you claim to be CBI. For CBI in a disk or CD ROM 

that you mail to EPA, mark the outside of the disk or CD ROM as CBI and then identify 

electronically within the disk or CD ROM the specific information that is claimed as 

CBI. In addition to one complete version of the comment that includes information 

claimed as CBI, a copy of the comment that does not contain the information claimed as 

CBI must be submitted for inclusion in the public docket. Information so marked will not 

be disclosed except in accordance with procedures set forth in 40 CFR part 2.

(3) Will the Agency Consider Late Comments?

EPA will consider all comments received before the close of business on the 

comment closing date indicated above under DATES. To the extent practicable, we will 

also consider comments received after that date. If interested persons believe that any 

new information the agency places in the docket affects their comments, they may submit 

comments after the closing date concerning how the agency should consider that 

information for the final rule. However, the agency’s ability to consider any such late 

comments in this rulemaking will be limited due to the time frame for issuing the final 

rule.

If a comment is received too late for us to practicably consider in developing the

final rule, we will consider that comment as an informal suggestion for future rulemaking 

action.
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(4) How Can I Read the Comments Submitted by Other People?

You may read the materials placed in the dockets for this document (e.g., the 

comments submitted in response to this document by other interested persons) at any 

time by going to http://www.regulations.gov. Follow the online instructions for accessing 

the dockets. You may also read the materials at the EPA Docket Center by going to the 

street addresses given above under ADDRESSES.

II. Direct Final Rule

In addition to this notice of proposed rulemaking, EPA is also publishing a Direct 

Final Rule (DFR) addressing provisions described in Sections III and IV of this 

document. We are doing this to expedite the regulatory process to allow the amendments

to occur as soon as possible. However, if we receive relevant adverse comment on 

distinct elements of any of the provisions in this proposal by [insert date 30 days after 

publication in the FEDERAL REGISTER], we will publish a timely withdrawal in the 

Federal Register indicating which provisions we are withdrawing. Any provisions of 

the DFR that are not withdrawn will become effective on [insert date 60 days after 

publication in the FEDERAL REGISTER], notwithstanding adverse comment on any 

other provision. We will address all public comments in the final rule based on this 

proposed rule. 

As noted above, EPA is publishing the DFR to expedite the regulatory process to 

allow engine and vehicle certifications and engine replacements to occur as soon as 

possible according to the clarified regulations. We request that commenters identify in 

your comments any portions of the proposed action described in Sections III and IV 

below with which you agree and support as proposed, in addition to any comments 
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regarding suggestions for improvement or provisions with which you disagree. In the 

case of a comment that is otherwise unclear whether it is adverse, EPA would interpret 

relevant comments calling for more flexibility or less restrictions for engines or vehicles

as supportive of the direct final rule. In this way, EPA will be able to adopt those 

elements of the DFR that are fully supported and most needed today, while considering 

and addressing any adverse comments received on the proposed rule, in the course of 

developing the final rule. See the DFR for the regulatory text associated with this 

proposal.

Note that Docket Number EPA–HQ– OAR–2012–0102 is being used for both the 

DFR and this NPRM.

III. Proposed Amendments to the Heavy-Duty Engine and Vehicle Greenhouse Gas 

Emission Standards Rule

EPA and the National Highway Traffic Safety Administration (NHTSA) 

developed the first-ever program to reduce greenhouse gas (GHG) emissions and fuel 

consumption in the heavy-duty (HD) highway vehicle sector. The rulemaking was 

developed as a single, national program with both EPA and NHTSA promulgating 

complementary standards that allow manufacturers to build one set of vehicles to comply 

with both agencies’ regulations. This broad heavy-duty 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. The final rule was published in the Federal Register on 

September 15, 2011 (76 FR 57106). 
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A. Background of the HD GHG and Fuel Efficiency Standards and Amendments

EPA’s GHG standards and NHTSA’s fuel consumption standards apply to 

manufacturers of the following types of heavy-duty vehicles and their engines:

Heavy-duty Pickup Trucks and Vans

Combination Tractors

Vocational Vehicles

The rules include separate standards for the engines that power combination 

tractors and vocational vehicles. Certain parts of the program are exclusive to EPA’s

GHG standards. These include EPA’s final hydrofluorocarbon standards to control 

leakage from air conditioning systems in combination tractors and in pickup trucks and 

vans. Also exclusive to the EPA rules are standards for nitrous oxide (N2O) and methane 

(CH4) emissions standards that apply to all heavy-duty engines and to pickup trucks and

vans.

EPA’s final greenhouse gas emission standards for heavy-duty vehicles 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. Both agencies allow manufacturers to comply early in model year 

2013 and promote early compliance by providing incentives to do so. 

In the final rulemaking, EPA established all-new regulations in 40 CFR parts 

1036, 1037, and 1066. EPA also included changes to existing regulations in 40 CFR 

parts 85, 86, 1039, 1065, and 1068. Similarly, NHTSA modified its existing regulations 

in 49 CFR parts 523 and 534, and established an all-new regulation in 49 CFR part 535. 
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After publication of the heavy-duty rule, EPA and NHTSA began an extensive 

outreach effort to aid in the rule’s implementation. For example, EPA and NHTSA held 

public workshops on November 3, 2011and August 10, 2012. In the course of these 

efforts, the agencies received a series of comments on specific aspects of the rules and 

prepared question and answer responses.1 In some cases, it became clear that minor 

changes to the rules would better clarify the rule’s intent, or amend the rule to make it 

more effective. The amendments proposed in this rule are largely based on these 

implementation discussions. 

The proposed revisions related to the heavy-duty GHG emissions regulations in 

this proposal are unique to EPA’s regulations. Thus, this section is further divided into 

subsections related to specific parts of the Code of Federal Regulations. 

B. Proposed Amendments to the Heavy-Duty GHG Regulations

The following proposed amendments correct minor, technical inconsistencies and 

add clarifications to the current regulatory text. EPA proposes to amend 40 CFR parts 

85, 86, 1036, 1037, 1065, and 1066 to correct typographical errors, clarify test procedures 

and certification procedures, and correct the regulations to make them consistent with the 

intent expressed in the preamble to the final rules (76 FR 57106). A comparison of the 

 

1

See U.S. EPA website at http://www.epa.gov/otaq/climate/regs-heavy-duty.htm.
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original and proposed regulatory text is provided in a memorandum to the docket for this 

rulemaking.2

(1) Proposed Regulatory Changes to 40 CFR Part 1036 

EPA proposes to amend portions of the regulations in 40 CFR part 1036, as 

described below. 

Hybrid Testing: §§ 1036.525 and 1036.615 specify requirements for testing 

hybrid engines and engines with Rankine cycle waste heat recovery. The 

regulatory text includes references for testing “post-transmission” and “pretransmission” hybrid systems in these sections. In a pre-transmission hybrid, the 

energy from both the engine and motor is input into the drive shaft prior to the 

transmission. In a post-transmission hybrid, the engine energy is input into the 

drive shaft prior to the transmission, but the motor energy is input into the drive 

shaft after the transmission. Since post-transmission hybrid architecture is 

incompatible with engine testing, EPA proposes to remove the reference to posttransmissions systems in the hybrid engine test requirements in 40 CFR part 

1036. 40 CFR 1037.525, 1037.550, and 1037.615 include requirements for 

testing post-transmission hybrids using a vehicle test. EPA anticipates that there 

would be no impact on manufacturers by the deletion of this text, since the 

vehicle test procedures set out in the regulations specify how to test posttransmission systems.

 

2 Hicks, M. and A. Cullen. Memorandum to Docket EPA-HQ-OAR-2012-0102. Heavy-Duty 

Engine and Vehicle Greenhouse Gas Emissions and Fuel Consumption Regulatory Changes. May 2013.
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EPA proposes to revise §§ 1036.5, 1036.150, and 1036.615 to address 

typographical issues to correct regulatory citations within the regulations.

EPA proposes to correct § 1036.150(g)(2) and (3) to change the assigned additive 

deterioration factor (DF) for nitrous oxide (N2O) and methane (CH4) emissions 

from 0.02 to 0.020 g/hp-hr to account for the appropriate number of significant 

digits.

EPA proposes to amend § 1036.225 to clarify that the CO2 family emission limit 

(FEL) is not required on the emission control information (ECI) label according to 

the provisions in § 1036.135.

EPA proposes to clarify that the CH4 and N2O emission standards apply to all 

testable configurations in § 1036.205.

EPA proposes to add a definition of “preliminary approval” to § 1036.801.

(2) Proposed Regulatory Changes to 40 CFR Part 1037 

EPA also proposes to revise portions of the regulations in 40 CFR part 1037 to 

correct technical errors and provide additional clarity in the regulations. 

(a) Hybrid Testing

Sections 1037.525, 1037.550, and 1037.615 describe or reference the procedure to 

be used for testing hybrid vehicles with power take off (PTO) devices on a whole vehicle 

test. Both pre- and post-transmission hybrid architectures can be used with power take 

off (PTO) devices. The current rule text states that manufacturers could test posttransmission hybrids on the vehicle test procedure to quantify CO2 and fuel consumption 

improvements resulting from running PTO equipment, but inadvertently excluded pre-
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transmission hybrid architecture from being tested on a vehicle test. Since PTO devices 

can also be used in hybrid vehicles with pre-transmission architecture, EPA is proposing 

to amend the language to allow these pre-transmission hybrid vehicles with PTO to be 

tested on the whole vehicle test procedure.

(b) Advanced Technologies Improvement Factor

Section 1037.615 describes the procedure for measuring CO2 improvements from

vehicles with hybrid and other advanced technologies (such as Rankine engines, electric 

vehicles and fuel cell vehicles), in order to generate advanced technology credits.3

Section 1037.615 specifies how manufacturers can measure the effectiveness of the 

advanced system by chassis-testing a vehicle equipped with the advanced system and an 

equivalent conventional vehicle using the test procedures in 40 CFR part 1037, subpart F. 

The effectiveness of the advanced system is calculated by measuring the CO2

output from chassis tests of the vehicle with the advanced system and an equivalent 

conventional vehicle, thereby obtaining the relative marginal improvement between the 

two vehicles (the “improvement factor”). The “benefit” associated with the advanced 

system is then calculated by multiplying the Greenhouse Gas Emissions Model (GEM) 

result for the vehicle with advanced technology by the dimensionless improvement 

factor. The benefit is then converted to advanced technology credits in a model year for 

each vehicle family within an averaging set. 

 

3 Advanced technology credits may be increased by a 1.5 multiplier and applied to any heavy-duty vehicle 

or engine subcategory with certain maximum limits applying. See 40 CFR 1036.740, 1037.740 and 49 

CFR 535.7(e) for description of advanced technology credit program. 
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The final rule specified the procedure for applying an improvement factor in 

simulating a chassis test with a post-transmission hybrid system for A to B testing (§

1037.550), but did not allow the improvement factor to be applied to multiple vehicle 

configurations having the same advanced technology (§ 1037.615). The posttransmission system test procedure specifically allows the application of an improvement 

factor or test results to multiple vehicle configurations, as long as the values used for the 

calculations “represent the vehicle configuration with the smallest potential reduction in 

greenhouse gas emissions as a result of the hybrid capability” and are consistent with 

good engineering judgement. EPA proposes to amend the regulatory text that describes 

the measurement of advanced technology improvement to include this specification as 

well. 

EPA proposes to revise § 1037.615 to allow manufacturers to generate advanced 

technology credits from multiple heavy-duty vehicle configurations within a vehicle 

family group by testing a single vehicle of that group, provided the vehicle tested has the 

smallest potential reduction in fuel consumption of the vehicles with advanced 

technology capability. EPA anticipates that this proposed change may reduce testing and 

reporting costs for manufacturers while still allowing flexibility in choosing to test

additional configurations within the family group. By limiting the use of this testing 

option to vehicles with the smallest potential reduction in emissions (or fuel 

consumption), emission reductions would not be compromised. 

(c) Optional Certification for Up to Class 6 Spark-Ignition Engine Vehicles

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 
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vehicles) manufactured as complete vehicles by a single or final stage manufacturer or 

manufactured as incomplete vehicles as designated by a manufacturer. Under the GHG 

rule, these vehicles are certified on a chassis dynamometer test, as opposed to the GEM 

simulation tool used to certify the vocational and tractor categories. NHTSA’s current 

regulations allow Classes 4 and 5 spark-ignition vehicles the option of certifying on a 

chassis dynamometer test, as those vehicles may have more similar characteristics to a 

Class 2b-3 pickup or van than they do other vehicles in their class. At the time of the 

final rule, NHTSA was unaware of any higher class spark ignition vehicles that would be 

similarly appropriate to test on a chassis dynamometer. EPA’s current regulations allow 

spark-ignition vehicles of all classes the option of certifying on a chassis dynamometer 

test.4

This proposed amendment would align the regulatory texts by closing the current 

gap between NHTSA and EPA’s optional certification provisions. EPA therefore 

proposes to allow manufacturers of complete or cab-complete vehicles up to and 

including Class 6 that have spark-ignition engines the option of chassis dynamometer 

certification. See references in §§ 1037.104 and 1037.150.

(d) Configuration and Subconfiguration Definitions

The existing EPA regulations contain definitions for “configuration” and 

“subconfiguration,” which define how to group vehicles by similar characteristics within 

a test group when conducting testing to determine CO2 emissions for heavy-duty pickup 

 

4

See 40 CFR 1037.15(l)
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trucks and vans. “Configuration” means a subclassification within a test group that is 

based on engine code, transmission type and gear ratios, final drive ratio and other 

parameters that EPA designates. Likewise, “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. 

The current definitions could be specified further according to established 

principles to prevent any ambiguity for manufacturers in conducting testing for heavyduty pickup trucks and vans. The terms “transmission type” and “engine code” can be 

further defined in the definition for “configuration,” to reflect common industry 

understanding of the terms. In addition, the term “equivalent test weight” could be 

further defined in the definition for “subconfiguration” to carryover the existing 

definition included in § 1037.104(d)(11). Therefore, EPA is proposing to add these

further details to clarify these terms in § 1037.104(d)(12). 

(e) Vocational Tractor Vehicle Families

The regulatory text in 40 CFR 1037.230 related to vocational tractor families is 

unintentionally ambiguous, and is inconsistent with, the preamble and other regulatory 

text. In the vocational tractor provisions of § 1037.630(b)(2), EPA requires that tractors 

“reclassified under this provision must be certified as a separate vehicle family. 

However, they remain part of the vocational regulatory subcategory and averaging set 

that applies to their weight class.” Although § 1037.630(b)(2) requires two vocational 

tractor families dependent on the GVWR of the vehicle, the text in § 1037.230(a)(1) 

implies only a single vocational tractor family default. This inconsistency is the result of 
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an oversight when provisions were added allowing tractors to certify as vocational 

vehicles, and it is inconsistent with the way vehicle families are treated throughout the 

program, where they are split by weight class (76 FR at 57240, September 15, 2011).

Therefore, EPA is proposing to revise § 1037.230(a)(1) to be consistent with §

1037.630(b)(2) by splitting the vocational vehicles families into two groups, those above 

33,000 pounds GVWR and those above 26,000 pounds GVWR and at or below 33,000 

pounds GVWR.

(f) 40 CFR Part 1037 Aerodynamic Assessment

A vehicle’s design impacts the amount of power that is required to move the 

vehicle down the road. Depending on the vehicle speed, two of the largest impacts on 

GHG emissions and fuel consumption are aerodynamics and tire rolling resistance. As 

part of the Heavy-Duty GHG and Fuel Efficiency rule, manufacturers are required to 

meet vehicle-based GHG emissions and fuel efficiency standards. Compliance with the 

vehicle standard for combination tractors is determined based on a vehicle simulation tool 

called the Greenhouse Gas Emissions Model (GEM). 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. See generally 76 FR 57135.

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 Heavy-Duty GHG and 

Fuel Efficiency rule, quantifying truck aerodynamics as an input to the GEM presents 

technical challenges because of the proliferation of vehicle configurations, the lack of a 
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clearly preferable standardized test method, and subtle variations in measured 

aerodynamic values among various test procedures (76 FR 57148-57151). 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. 

We developed a broad approach that allows manufacturers to use these multiple 

different test procedures to demonstrate aerodynamic performance of the tractor fleet 

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. 

EPA and NHTSA developed a bin structure to group aerodynamic test results for 

the proposed rulemaking, and adjusted the method used to determine the bins in the final 

rule. The agencies, while working with industry, developed an approach for the final 

rulemaking which identified a reference aerodynamic test method and a procedure to 

align results from other aerodynamic test procedures with the reference method, an 

enhanced coastdown procedure. Manufacturers are 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. 

As discussed in the final rule, the agencies adopted aerodynamic technology bins 

which divide the wide spectrum of tractor aerodynamics into five bins (i.e., categories) 
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for high roof tractors (see 76 FR 57149). The first high roof category, Bin I, is designed 

to represent tractor bodies that prioritize appearance or special duty capabilities over 

aerodynamics. These Bin I trucks incorporate few, if any, aerodynamic features and may 

have several features that 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 that 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 that 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. 

EPA and NHTSA developed the aerodynamic drag area, CdA, bin values for the 

tractor categories based on coastdown testing conducted by EPA using the enhanced 

coastdown test procedures adopted for the final HD GHG and Fuel Efficiency 

rulemaking. EPA tested high roof sleeper cab combination tractors from each of the 

manufacturers in order to represent the aerodynamic performance that we would expect 
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from a Bin III vehicle. The test results used for the HD GHG and Fuel Efficiency final 

rule are included in Table III-1 below.5

Table III-1: Tractor CdA Values used in HD GHG Final Rule

Truck Expected Bin Source CdA (m2)

Class 8 High Roof Sleeper Cab

B-3JM2-2H-TXCR Bin III EPA Test Program 6.4

B-3JM2-4N-TXCR Bin III-IV EPA Test Program 5.7

B-3JM2-2K-TXCR Bin III EPA Test Program 6.3

C-3JM2-1B-TXCR Bin III EPA Test Program 6.2

C-3JE2-1F-TXCR Bin II-III EPA Test Program 6.7

As part of EPA’s quality checks to the enhanced coastdown test program, EPA

supplied OEMs with the coastdown test data for their individual trucks. Through postrulemaking work with one OEM, EPA found an error in the data attributable to a testing 

contractor. The contractor had entered the same coastdown run twice into the dataset 

provided to EPA for one of the trucks tested (one of 20 repeat runs was entered twice). 

As a result the truck appeared to have a CdA value of 5.7, rather than its actual value of 

6.6. As such, the data that should have been used to establish the aerodynamic bins for 

the high roof sleeper cabs are listed in Table III-2.

 

5 U.S. EPA and NHTSA. Final Rulemaking to Establish Greenhouse Gas Emissions Standards and Fuel 

Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles – Regulatory Impact Analysis. 

August 2011. Page 2-48.
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Table III-2: Tractor CdA Values used in this NPRM

Truck Expected Bin Source CdA (m2)

Class 8 High Roof Sleeper Cab

B-3JM2-2H-TXCR Bin III EPA Test Program 6.4

B-3JM2-4N-TXCR Bin III EPA Test Program 6.6

B-3JM2-2K-TXCR Bin III EPA Test Program 6.3

C-3JM2-1B-TXCR Bin III-IV EPA Test Program 6.2

C-3JE2-1F-TXCR Bin II-III EPA Test Program 6.7

Since the coastdown test is an input into the aerodynamic bins, EPA proposes to 

correct the CdA range for the affected bin levels. The proposed adjustment to the ranges 

would allow Bin III, which represents a SmartWay truck, to still mean exactly what was 

intended in the HD GHG and Fuel Efficiency final rule. The proposed Bins IV and V 

adjustments would require the same level of improvement we expected in the HD GHG 

and Fuel Efficiency final rule. This proposed amendment is a correction, so will not

change the standards or the costs or projected emissions reductions. The HD GHG and 

Fuel Efficiency rulemaking estimates of technology costs and the resulting aerodynamic 

efficiency improvements were made separately from the test procedure normalization 

reflected in the bin tables. Those cost and technical feasibility assessments set the 

absolute values of the steps in the table, where the testing results of the five tractors in 

Table III-2 set the range of Bin III against which the rest of the aerodynamic bins are 

defined. Since EPA is not proposing to change either the technical descriptions of the 

bins or the estimates of the aerodynamic loss or benefits in moving between bins in the 

table, EPA is estimating no change in HD GHG and Fuel Efficiency final rulemaking 

costs or benefits. EPA is also not proposing to change the input into GEM related to each 
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aerodynamic bin; therefore, this proposed change would have no impact on the GHG or 

on fuel consumption standards.

EPA proposes to make the adjustments shown in Table III-3 to correct the 

technical error in the coastdown data used in the HD GHG and Fuel Efficiency final rule. 

The proposed bin value adjustments would be used by manufacturers to certify their 

vehicles in their 2013 MY and later end of year reports.

Table III-3: Proposed Table in § 1037.520(b)

High-Roof Sleeper Cabs

If your measured CDA 

(m2) is . . .

Then your Bin Level 

is...

Then your CD input is . . 

.

≥ 7.6 Bin I 0.75

6.8-7.5 Bin II 0.68

6.3-6.7 Bin III 0.60

5.6-6.2 Bin IV 0.52

≤5.5 Bin V 0.47

(g) Other 40 CFR Part 1037 Proposed Amendments

Heavy-Duty Pickup Truck and Van Regulations: EPA proposes to amend several 

provisions in §§ 1037.15 and 1037.104 to specify which parts of 40 CFR part 86 

apply to these vehicles and to specifically reference portions of 40 CFR part 86 in 

40 CFR part 1037. EPA also proposes to revise the language in § 1037.150(a)(2)

to make it consistent with the preamble to the final rule, which stipulates that the 

entire heavy-duty pickup truck and van fleet must be certified to qualify for early 

credits (see 76 FR 57245). Also, EPA proposes to clarify how heavy-duty pickup 

truck and van subconfigurations are selected for testing in § 1037.104(d)(9)(i) 

through (iii). EPA is also proposing to revise § 1037.104(g)(2)(ii), (g)(2)(iv), and 
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(g)(5) to clarify the approach for estimating analytically derived CO2 emission 

rates (ADCs). 

Air Conditioning (A/C) Leakage Provisions: The MY2017-2025 Light-Duty 

GHG and Fuel Economy Rule separated 40 CFR 86.1866 into four sections for 

clarity. The A/C leakage section moved to 40 CFR 86.1867-12. Thus, EPA 

proposes to amend § 1037.115 to reflect this change. In addition, EPA proposes 

to revise § 1037.115 because the procedure for determining the 

hydrofluorocarbon (HFC) leakage rate for air conditioning systems with alternate 

refrigerants is already addressed in SAE J2727, which is incorporated by 

reference in 40 CFR 86.1, and therefore does not need to be included in §

1037.115.

Labeling clarification: EPA proposes to clarify in § 1037.135 that the emission 

control label for the vehicle only requires a statement regarding the size of the 

fuel tank for vehicles that contain an evaporative canister for controlling 

emissions.

Typographical fixes: EPA proposes to address the typographical errors in §

1037.135 relative to labeling, § 1037.501 related to the trailer specification, and §

1037.520 which includes a weight reduction explanation.

EPA proposes to clarify that the general requirements for obtaining a certificate of 

conformity and EPA’s authority to perform confirmatory testing on vehicles, 

including the vehicles used to determine Falt-aero (see § 1037.201).

EPA proposes to revise § 1037.550 to change the nomenclature used for the 

vehicle speed variable from S to v to be consistent with 40 CFR part 1065. EPA 
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is also proposing to remove the torque control option for testing post-transmission 

hybrid systems because it causes testing issues when the vehicle is shifting and 

braking and by removing the torque control mode from the dynamometer control 

options it would reduce lab-to-lab variability.

EPA proposes to clarify the regulatory text in § 1037.620(a)(3) for instances 

where the secondary manufacturer who would hold the vehicle GHG certificate 

may be a small business that would be exempted from the GHG regulations.

EPA proposes to revise § 1037.660 related to the automatic engine shutdown 

(AES) provisions. § 1037.660(c) currently allows manufacturers to obtain a 

discounted credit for installing AES systems that expire prior to the end of the 

vehicle’s life based on the ratio of the set point relative to 1,259,000 miles.6 EPA 

is not revising that provision, except to change the regulatory provision 

numbering from § 1037.660(c) to § 1037.660(c)(1). EPA is not revising that 

provision. However, similar to the reasons which supported the development of 

vehicle speed limiter flexibilities, an automatic engine shutdown system could be 

developed to alleviate other potential concerns that impede its adoption. For 

example, some amount of idling may be needed for truckers who experience 

significant ambient temperature excursions that would necessitate extended idling 

or for idle reduction technologies, such as auxiliary power units, that malfunction 

 

6 The basis for the lifetime mileage assumption for heavy-duty tractors is discussed in the 

Regulatory Impact Analysis for the Final Rule on page 2-69. Available in Docket # EPA-HQ-OAR-2010-

0162-3634
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and necessitate extended idling. A remedy to these concerns would be to design 

the AES such that it allows for a predetermined number of hours per year of 

idling. EPA is proposing to add § 1037.660(c)(2) to appropriately quantify the 

CO2 emissions and fuel consumption of a partial AES system by discounting the 

AES input to GEM. EPA is using an assumption of 1,800 hours as the annual

idling time in the calculation, which is consistent with the final rule (76 FR 

57154). EPA used 1,800 hours as the annual idling time for sleeper cabs because 

it reasonably reflects the available range of idling time cited in several studies, as 

discussed in the preamble to the final rule and in the Final Regulatory Impact 

Analysis (pages 2-67 and 2-68).7 The 1,800 hours of idling was used in the final 

rule to determine the credit of 5 grams of CO2 per ton-mile for the use of AES 

systems (page 2-68 of the Final Regulatory Impact Analysis).

EPA proposes to add a provision to § 1037.745. This new proposed provision 

would clarify manufacturers’ liability for offsetting debits (or deficit credits) after 

certifying with emissions above the standards for three years. We want to avoid 

claims that the statute of limitations starts to apply in the first year of using debits, 

since this could significantly limit our ability to adequately enforce the 

requirement. We have generally adopted this approach in other rules that allow 

debits to be carried forward a given number of model years and are later offset 

 

7 Regulatory Impact Analysis: Final Rulemaking to Establish Greenhouse Gas Emissions 

Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles. August 

2011. Available in Docket # EPA-HQ-OAR-2010-0162-3634.
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with credits (40 CFR 86.1861-04(e), 86.1864-10(o), and 86.1865-12(k)).

EPA proposes to add a definition of “preliminary approval” to § 1037.801.

EPA proposes to revise the “Regulatory Sub-category” definitions in § 

1037.801 to match the definition of “Class” in 40 CFR 1037.801, be consistent 

with DOT’s Gross Vehicle Weight Rating Classes in Table II of 49 CFR 

565.15, and aggregate the heavy-duty pickup truck and van sub-category to 

match the definition in 49 CFR 535.4.

(3) Proposed Regulatory Changes to 40 CFR Parts 1065 and 1066

EPA proposes to restore text to § 1065.610(c)(3)(i) through (iii) which was 

inadvertently removed in the final rule for Category 3 marine diesel engines (75 FR 

22896, April 30, 2010). This text was most recently published in the final rule adopting 

standards for locomotive engines and Category 1 and Category 2 marine diesel engines 

(73 FR 37325, June 30, 2008).

EPA is also proposing to revise portions of the regulations in 40 CFR part 1066 to 

clarify test procedures. Specifically, we propose to revise § 1066.310(b) to clarify the 

coastdown process and simplify the anemometer calibration process.

(4) Proposed Regulatory Changes to 40 CFR Part 85 

EPA proposes to revise § 85.525 to separate the light-duty and heavy-duty fuel 

conversion regulations to provide clarity regarding the applicability of the fuel 

conversion regulations to heavy-duty pickup trucks and vans. 

(5) Proposed Regulatory Changes to 40 CFR Part 86 

EPA is also proposing to revise portions of the regulations in 40 CFR part 86. 

First, EPA is revising § 86.010-18(q) to provide a mechanism for engine manufacturers 
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to identify engines which are only suitable for installation in hybrid applications due to 

the on-board diagnostics (OBD) calibration. Manufacturers who opt to produce a unique 

set of engines for hybrid applications will include a compliance statement on the ECI 

label that states “for use in hybrid applications only.”

Second, EPA proposes to revise portions of § 86.1865-12 to clarify the provisions 

that specifically apply to the heavy-duty pickup trucks and vans subject to 40 CFR 

1037.104. 

Third, EPA proposes to remove §§ 86.007-23(n) and 86.1844-01(j), which 

describe how to report CO2, N2O, and CH4 emissions. There is no need or benefit for 

manufacturers to submit greenhouse gas emission data in the model years before 

emission standards apply for those pollutants. 

(6) Summary of Proposed Heavy-Duty GHG Amendments

EPA does not expect that these proposed revisions to 40 CFR parts 85, 86, 1036, 

1037, 1065, and 1066 would have any adverse cost impact to the manufacturers. There 

are no testing costs associated with the proposed revisions. There would be no 

environmental impact associated with this regulatory action because this proposed 

rulemaking would not change the heavy-duty engine and vehicle greenhouse gas

emission standards that manufacturers have to meet; it simply makes some minor 

amendments to the regulations.

IV. Other Technical Amendments

A. Replacement Engines

In 1996, EPA adopted a provision allowing manufacturers in limited 

circumstances to produce new, exempt engines for replacing failed engines (61 FR 
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58102, November 12, 1996). With this approach, manufacturers have been able to make 

new, exempt engines in cases where engines certified to current standards do not have the 

physical or performance characteristics needed to power the equipment with the old 

engine. Without this provision, some equipment owners would have been forced to 

prematurely scrap otherwise working equipment (sometimes worth millions of dollars), 

because no engine meeting current emission standards could be adapted for installation in 

the space occupied by the original engine.

EPA later added language to the replacement engine exemption to address the 

complications related to producing partially complete engines for replacement purposes, 

and to address the need to produce and sell replacement engines such that they would be 

available to operators with a critical need to avoid extended downtime in the case of 

engine failure (73 FR 59034, October 8, 2008). This expanded approach allowed 

manufacturers to sell a limited number of new, exempt replacement engines without 

taking the steps that would otherwise be required to document the need for the exemption 

and to arrange for the proper disposition of the old engine. Along with this expanded 

approach, EPA added circumvention language to describe the overall purpose of the 

replacement engine exemption in an attempt to prevent manufacturers and operators from 

using exempted engines in ways that were unnecessary and/or detrimental to the 

environment. In particular, this text states that the provisions § 1068.240 are “intended to 

allow for replacement of engines that fail prematurely . . .” This language has been 

interpreted to mean that replacement engines may be used for no other purpose.

Since then, EPA has found that the circumvention language has had some 

unintended consequences. For example, California has adopted requirements for 
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operators to reduce emissions from in-use equipment, which has led to a desire to install 

new replacement engines that are cleaner than the old engines. It is often the case that it 

is infeasible or impractical to install replacement engines certified to current standards, 

but suitable replacement engines designed to meet an intermediate level of emission 

standards are available. The circumvention language may prevent operators in 

California from achieving overall emission reductions that would result from upgrading 

their existing equipment with cleaner engines in this manner. It may also be the case that 

an engine will simply wear out, rather than experiencing premature failure, well before 

the equipment in which it is installed is at the end of its life. Under the current 

regulation, an operator under these circumstances would need to install a new engine 

certified to current standards, or find a used engine, to keep the equipment operating.

EPA continues to believe that new, exempt replacement engines should only be 

used in cases where a currently certified engine cannot practically be installed to power 

the old equipment. EPA believes the regulatory language without our description of 

intent to prevent circumvention serves this purpose without the unintended consequences 

described above. EPA is therefore proposing to remove the circumvention provisions 

from the regulations in § 1068.240. EPA expects manufacturers and operators following 

the regulations to continue to use the exemption provisions appropriately and not for the 

purpose of circumventing the emission standards. EPA is proposing to add language to 

explicitly limit this provision to equipment that has been in service 25 years or less (at the 

point of installation) so that manufacturers and operators do not use this provision to keep 

in operation older dirtier, equipment beyond the normal lifetime of the equipment, by 

continually using new engines to replace old engines. EPA has adopted this same 
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restriction for stationary engines under 40 CFR 60.4210(i), except that the maximum 

equipment age is 15 years. EPA will continue to monitor compliance with the exemption 

provisions and will consider any appropriate changes to the regulation in the future to 

ensure that the exemption is properly used toward this purpose. This proposed 25-year 

limit would not apply for marine diesel engines, since those engines are subject to 

separate replacement engine provisions.

The proposed tracked option specified in § 1068.240(b) also includes an 

additional step to qualify for the replacement engine exemption for equipment not 

experiencing premature engine failure. In particular, manufacturers would need to make 

a determination that the replacement engine is designed with the greatest degree of 

emission control that is available for the particular application. For example, if the

engine being replaced was built before the Tier 1 standards started to apply and engines 

of that size are currently subject to Tier 2 standards, the manufacturer would need to also 

consider whether it produces any Tier 1 or Tier 2 engines with the appropriate physical 

and performance characteristics for replacing the old engine. If the manufacturer 

produces a Tier 1 engine with the appropriate physical and performance characteristics, 

engines emitting at levels above the Tier 1 standards would not qualify for an exemption. 

The proposed requirement to use the cleanest available engine fits with the intent of 

facilitating voluntary incentive programs involving replacement engine upgrades toward 

the goal of reducing emissions from in-use equipment, but without imposing a 

requirement that would involve new technology development or impractical equipment 

design changes. This provision has already been in place for marine diesel engines in §

1042.615. In the case of equipment experiencing premature engine failure, we would 
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continue to apply the simpler requirement that the replacement engine must meet 

emission standards that are the same as or better than the standards that apply to the old 

engine. 

EPA is also proposing to adjust the provisions related to the disposition of the old 

engine in § 1068.240(b). To be re-introduced into U.S. commerce, the old engine must 

either meet current emission standards or qualify for an exemption as if it were a new 

engine. The old engine could be re-used as a replacement engine for a different piece of 

equipment. Under this proposed approach, an engine made from all new parts and an 

engine built with a used engine block and any mix of new or used additional parts would 

be treated the same way. For example, the recycled replacement engine would be subject 

to all the demonstrations and documentation requirements of § 1068.240(b), and it would 

count toward the allowance to produce a limited number of replacement engines under §

1068.240(c). For engines that are not re-introduced into U.S. commerce, manufacturers 

must destroy the old engine or confirm that it has been destroyed. These proposed 

changes would further address the concern expressed in the circumvention language 

described above; in particular, EPA believes it is necessary to prevent the possibility of 

these old engines being installed in new equipment.

EPA is also proposing some clarification to the regulations to address questions 

that have arisen, as well as making the following changes:

Proposing revision of the labeling requirements to account for the possibility of using 

a new replacement engine to replace a previously exempted replacement engine. To 

the extent that the proposed revised label statement differs from that specified by 
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California ARB, we would expect to approve an adjusted statement that allows for a 

single, 50-state label under § 1068.201(c).

Proposing to adjust the reporting deadline for untracked replacement engines under §

1068.240(c). This proposed change would allow manufacturers some time after the 

end of the calendar year to make the determinations and to take the required steps to 

fulfill the tracking requirements for replacement engines under § 1068.240(b). Any 

engines for which these steps and determinations are incomplete by the deadline for 

the report would need to be counted as untracked replacement engines. Further, to 

account for prevailing practices and typical timelines for replacement engines, we 

would move back the deadline for this report from February 15 to March 31. 

Proposing to revise § 1068.240(c)(1) to specify that manufacturers may base sales 

limits for the untracked option on total U.S. production of certified and exempted 

engines together (including stationary engines).

Proposing to add language to clarify that § 1068.240(e) applies only for engines 

produced under a current, valid certificate. An exemption under § 1068.240(b) or (c) 

would be required to produce an engine that is identical to one that is no longer 

certified, even if the engine was formerly certified to standards (or a Family Emission 

Limits) that are at least as stringent as the current standards.

Proposing clarifications to the provisions in § 1068.240(d) related to partially 

complete engines also apply for “current-tier” replacement engines exempted under §

1068.240(e).

Proposing to add a statement to § 1042.615 for marine diesel engines to clarify our 

pre-determination that certified Tier 4 engines do not have the appropriate physical 
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and performance characteristics for replacing older engines in marine vessels. This 

policy was established in our June 30, 2008 final rule (see 73 FR 37157).

In addition, we are proposing to revise § 1068.1 to correct two errors regarding 

the applicability of part 1068. First, we propose to restore highway motorcycles to the 

list of categories that are not subject to part 1068. This was added, but then inadvertently 

removed, when we were completing two parallel rulemakings. Second, we are proposing 

to add a reference to 40 CFR part 85 to identify how part 1068 applies in certain 

circumstances for heavy-duty highway engines. These proposed changes are intended to 

clarify and reinforce existing requirements without modifying the underlying programs in 

any way.

B. Nonroad Diesel Engine Technical Hardship Program

EPA is proposing to amend the nonroad diesel engine technical hardship program 

to facilitate EPA granting exemptions to address certain hardship circumstances that were 

not considered when the original 2004 final rule was published. EPA adopted Tier 4 

standards for nonroad diesel engines under 40 CFR part 1039 in 2004 (69 FR 38958, June 

29, 2004). To meet these standards, engine manufacturers are pursuing development of 

advanced technologies, including new approaches for exhaust aftertreatment. Equipment

manufacturers will need to modify their equipment designs to accommodate these new 

engine technologies and the corresponding changes to engine operating parameters (such 

as operating temperatures and heat rejection rates). To provide flexibility for equipment 

manufacturers in their efforts to respond to these engine design changes, the Tier 4 

standards included the Transition Program for Equipment Manufacturers. Flexibilities 

allowed under this program include delaying compliance with small-volume equipment 
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models for several years or using allowances in the first year to manage the transition to 

the Tier 4 engines.

The Transition Program for Equipment Manufacturers is intended to allow 

nonroad equipment manufacturers wide discretion to manage their product development 

timeline. Equipment manufacturers may comply either based on a percent of their 

production (generally for high-volume manufacturers, as described in § 1039.625(b)(1)), 

or based on a maximum number of exempted pieces of equipment (generally for lowvolume manufacturers, as described in § 1039.625(b)(2)). At the same time, the 

regulations include at § 1039.625(m) an acknowledgement that equipment manufacturers 

might face a wide range of circumstances, including cases where engine manufacturers 

might be late in providing compliant engines to nonintegrated equipment manufacturers 

such that the specified allowances are insufficient to avoid a disruption in the equipment 

manufacturer’s production schedule. The technical hardship provision at § 1039.625(m) 

allows EPA to make a judgment that an equipment manufacturer that buys engines from 

another company, through no fault of its own, needs additional allowances to manage the 

transition to Tier 4 products. The regulation specifies a maximum allowance of 150 

percent of a manufacturer’s annual production (relative to § 1039.625(b)(1)), or a total of 

1,100 allowances (relative to § 1039.625(b)(2)). The regulation also provides economic 

hardship provisions under § 1068.255; however, eligibility depends on manufacturers 

showing that their solvency is in jeopardy without relief. Economic hardship therefore 

serves as a flexibility provision of last resort.

As the compliance dates for the Tier 4 standards approach, equipment 

manufacturers have described several scenarios where the technical hardship provisions 
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are too restrictive to address their circumstances. For example, engine manufacturers 

have in some cases delayed delivery of Tier 4 engines until six or even twelve months 

after the Tier 4 standards start to apply, which could force equipment manufacturers to 

use up all their allowances under § 1039.625(b) in the first year of the new standards. 

The maximum number of allowances under § 1039.625(m) would cover a good portion 

of the second year of the Tier 4 standards, but we have heard how this too is inadequate 

to allow equipment manufacturers to respond to late deliveries of compliant engines. 

As another example where additional flexibility may be warranted, corporate 

acquisitions can cause equipment manufacturers to find themselves disadvantaged with 

respect to allowances because two companies have become a single company for 

purposes of regulatory compliance. Taken to an extreme, the combined company could 

exceed its allowances under § 1039.625(b) on the day of the merger because each of the 

separate companies may have used allowances that, taken together, exceed the specified 

thresholds for a single company. The combined company may apply for technical 

hardship under § 1039.625(m), but we have seen that this too can provide insufficient 

relief for equipment manufacturers trying to incorporate Tier 4 engines into their 

equipment.

In these cases, the maximum allowable relief under § 1039.625(m) is insufficient 

to allow equipment manufacturers to transition to meeting Tier 4 requirements without 

disrupting their ability to continue producing their equipment models. There have also 

been cases where a company would meet the criteria to qualify for consideration for 

technical hardship under § 1039.625(m) except that the regulation disallows technical 

hardship relief for all engines above 560 kW and provides only limited relief for engines 
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above 37 kW. The regulation also provides only limited relief for companies that are not 

small businesses. In these cases, no additional relief is available under § 1039.625(m), 

which again leaves equipment manufacturers unable to continue producing their 

equipment models.

We are proposing to amend the Transition Program for Equipment Manufacturers 

in three ways to address these concerns. First, we propose to remove the qualifying 

criteria so that any equipment manufacturer may apply for technical hardship relief under 

§ 1039.625(m) for any size engine, rather than limiting the technical hardship relief to 

small businesses and to engines within certain power categories. We believe it is more 

appropriate to rely on our discretion to evaluate each hardship application on its merits 

rather than automatically precluding hardship relief based on certain characteristics of the 

engine or the company. If hardship relief is not appropriate because of an engine’s power 

rating or a company’s size or financial standing, we would not approve the request. 

Second, we propose to remove the maximum number of allowances we can 

approve under § 1039.625(m), for both percent-of-production (currently 150 percent) and 

small-volume allowances (currently 1,100 units), and we propose to remove the deadlines 

for exercising those additional allowances. We have learned that the specified 

restrictions on hardship allowances are in some cases too limiting to address the 

legitimate concerns raised by equipment manufacturers. Again, we believe it is most 

appropriate to resolve issues of extent of relief once an equipment manufacturer has 

demonstrated that relief is appropriate, rather than limiting it a priori. We would not 

approve a greater number of technical hardship allowances than is needed to meet the 

established objectives. Finally, we are proposing additional small-volume allowances 
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under § 1039.625(b)(2) and (m)(4), where we may waive the annual limits on the number 

of allowances instead of or in addition to granting additional hardship allowances. There 

may be times when manufacturers only need approval to use up their regular allowances 

at a faster pace than the regulations currently allow.

An additional concern has come to our attention as it relates to marine engines. 

Vessel manufacturers may use certified land-based engines in marine vessels as long as 

the engines are not modified from their certified configuration (see § 1042.605). We 

adopted this provision with the understanding that, given the additional technological 

challenges of operating engines in a marine environment, marine standards are set to be 

no more stringent than land-based standards and are often set at a level somewhat less 

stringent than the standards that apply to the land-based engines. Vessel manufacturers 

have used these provisions extensively to access a wide range of engine models that are 

not available in a certified marine configuration. The part 1039 Tier 4 standards have 

made this more complicated. The Tier 4 standards for land-based engines are much more 

stringent than the Tier 3 marine standards, which will continue to apply for many 

Category 1 engines. Engine distributors supplying product to vessel manufacturers have 

reported that several engine models will not be available to them in the transition period. 

In that way, vessel manufacturers are much like nonroad equipment manufacturers, 

except that the vessels are not actually required to use engines meeting the more stringent 

standards now or, for engines below 600 kW, in the foreseeable future. It would be a 

natural solution to use allowances under § 1039.625, but the regulations specifically 

require that vessel manufacturers may use only certified land-based engines under §

1042.605. There is a risk that this gap would significantly limit their ability to continue 
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producing vessels in the near term. We are proposing to address this by revising 40 CFR 

part 1042 to specifically allow vessel manufacturers to use allowances under § 1039.625 

for certain model year 2013 engines installed in marine vessels. This proposed provision 

would not apply for engines at or below 19 kW, since the land-based and marine 

standards for those engines are very similar. This proposed provision also would not 

apply for engines above 600 kW because the dynamic for designing and certifying those 

high-power engines allows for a greater expectation that they will be certified in a marine 

configuration. We expect no negative environmental impact because the engines will be 

meeting the nonroad Tier 3 standards, which will continue to be at least as stringent as 

the standards that currently apply for marine engines. It is important to note that this is 

only a temporary measure; once allowances are no longer available under § 1039.625, 

vessel manufacturers will either need to use Tier 4 land-based engines or find certified 

Tier 3 marine engines. 

There are further minor proposed changes to the regulations to clarify some of the 

detailed transition provisions for nonroad diesel engines, as follows:

Proposing to revise § 1039.104(g) to remove the limitations on the number of engines 

using the specified alternate FEL caps. Manufacturers have pointed out that this 

expanded flexibility would address the same concerns as described in this section for 

transitioning to the Tier 4 standards, but there would be no net environmental impact 

since manufacturers would need to produce low-emission engines that generate 

emission credits to offset the additional credits used by transition engines certified to 

with higher FELs. We are also proposing to revise the regulation to specify that the 

same Temporary Compliance Adjustment Factor is the same whether an engine is 
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subject to NOx+NMHC standards or NOx-only standards. The proposed revision 

also addresses Tier 3 carry-over engines that would need to certify to the alternate 

FEL caps after the Tier 4 final standards take effect.

Proposing to add text to § 1039.625(e) to clarify that exempted engines may meet 

standards that are more stringent than those specified in the regulation. This proposed 

change is intended only to avoid the unintended consequence of disallowing a 

manufacturer from making an engine that was cleaner than it needed to be. Even 

though these engines are cleaner than they need to be under the replacement-engine 

exemption, it is still the case that these engines are being exempted from the 

standards that apply for certified engines; as such, it would be inappropriate for these 

engines to generate emission credits.

Proposing to clarify § 1039.625(e) which alternate standards apply to exempted 

engines in cases where there is more than one set of standards in a given model year. 

For example, the appropriate standards for 19-56 kW engines are the Option 1 

standards specified in § 1039.102, and the appropriate standards for bigger engines 

are the phase-out standards specified in § 1039.102.

Proposing to adjust the provision for using interim Tier 4 engines under § 

1039.625(a)(2) to require that manufacturers use engines that are identical to 

previously certified engines, rather than requiring that the exempt engines be certified 

for the new model year. This addresses an administrative complication related to 

certifying exempted engines, without changing the requirements that apply.
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C. Large SI Fuel Line Permeation

EPA is proposing to amend the required version of the SAE procedure for testing 

large SI fuel line permeation. In 2002 we adopted evaporative emission standards for 

nonroad spark-ignition engines above 19 kW (Large SI engines) (67 FR 68242, 

November 8, 2002). This rule included a requirement that engines meet a permeation 

control standard, that could be demonstrated by using fuel lines compliant with SAE 

J2260, the latest version of which had been completed in 1996 (see 40 CFR 1048.105). 

This SAE standard effectively established a level of permeation control that had been 

widely used with automotive products. In adopting this requirement, we expected 

manufacturers to find “off-the-shelf” automotive-grade products for the nonroad engines 

and equipment. 

In 2008, we revised this requirement by changing the regulation to reference the 

2004 version of SAE J2260, which had been finalized after the initial rulemaking (73 FR 

59034, October 8, 2008). As noted in our proposed rule, we understood the purpose and 

effect of the change in the SAE standard to be substantive with regard to the permeation 

measurement procedure, but not necessarily with regard to the stringency of the standard. 

The revised SAE protocol specifies a tighter numerical standard, but this corresponded to 

an offsetting change from a methanol-based test fuel to an ethanol-based test fuel. 

Switching to ethanol improves the representativeness of the procedure, and it is widely 

understood that ethanol permeates through fuel-system materials less aggressively than 

methanol. It is also clear the fuel change would have a non-uniform effect on different 

fuel-system materials, but our overall expectation was that fuel lines meeting the 1996 

version of the standard would also meet the 2004 version of the standard. Following the 
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proposed rule, we received no comments either supporting or contradicting our 

understanding that updating to the new standard would have no significant effect on the 

stringency or practicability of the standard. 

Since completing the 2008 rulemaking, we have received information indicating 

that the revision of the regulation to refer to the newer version of SAE J2260 was having 

a substantive effect on manufacturers’ ability to meet the standard. First, it seems that 

automotive manufacturers have moved beyond the SAE J2260 standard to develop their 

own proprietary methods of sourcing fuel lines from their suppliers. Since the 

evaporative emission standards for automotive products involve whole-vehicle 

measurements in an enclosure, manufacturers have the option to pursue different 

strategies of balancing emissions from fuel-line permeation with emissions from other 

sources. In effect, there is no longer a level of emission control or a type of fuel line that 

we can characterize simply as "automotive-grade". It is also the case that motor vehicle 

manufacturers buy fuel lines in large quantities of pre-formed parts, rather than buying 

large spools of fuel line that can be cut and formed for a particular application.

Second, it appears that fuel line suppliers have a very limited ability or 

willingness to supply fuel lines that they will describe as meeting the 2004 version of 

SAE J2260. It is not clear whether this is a result of a difference in stringency between 

the two versions of the standard, or merely that fuel-line suppliers have moved beyond 

the SAE standard to conform to separate specifications from individual automotive 

manufacturers. In any case, Large SI equipment is not manufactured in sufficient 

numbers to greatly influence the fuel line manufacturers’ activities, which has prevented 
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Large SI equipment manufacturers from being able to find and use fuel lines meeting the 

exact specification in the regulations.

We are proposing to address this by again revising the regulation, this time to 

specify that either the 1996 or 2004 version of SAE J2260 provides an acceptable level of 

control for producing compliant Large SI engines and equipment. We do not believe this 

would have a significant effect on the stringency of the standard. However, to the extent 

that this would modify the stringency of the existing fuel-line permeation standards at all, 

it only revises it back to the level of permeation control that we adopted originally in 

2002. We note also that the regulations from the California Air Resources Board 

continue to rely on the 1996 version of SAE J2260. This proposed change therefore 

would allow for a unified national approach to fuel-line permeation standards.

D. Small SI Proposed Amendments

Since the first emission standards for small spark-ignition (SI) engines (< 19kW), 

EPA and the California ARB have required the same basic exhaust emission test 

procedures and durability aging requirements. Both agencies have accepted exhaust 

emission test results on either agency’s test fuel for purposes of certification. This has 

traditionally meant that for small SI engines used in either handheld or non-handheld 

equipment, EPA would accept exhaust emission test results based on either its Indolene 

test fuel (specified at 40 CFR 1065.710) or on California test fuel (specified at section 

2262 in the California Code of Regulations (13 CCR 2262)). In 2008, when EPA 

promulgated the current small SI exhaust emission standards, the California test fuel, 

commonly referred to as California Phase 2 gasoline or CA RFG 2, was a seven pound 

per square inch (psi) Reid Vapor Pressure (RVP) gasoline which had approximately 11 
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percent methyl tertiary butyl ether (MTBE) as an oxygenate additive. This test fuel had 

been used in the California small off road emission (SORE) program since 1995. 

Our 2008 final rule included provisions at § 1054.145(k) indicating that EPA 

would not accept carryover exhaust emission certification data on CA RFG 2 after the 

2012 model year (73 FR 59034, October 8, 2008). However, we left open the possibility 

of continuing to accept carryover exhaust emission test data on CA RFG 2 subject to the 

provisions of 40 CFR 1065.10, 1065.12 and 1065.701, which would permit EPA to 

approve its continued use if it does not affect the manufacturers’ ability to show that the 

affected engines would comply with all applicable emission standards using the fuel 

specified by EPA in 40 CFR 1065.710. Manufacturers have recently provided emissions 

data meeting the regulatory requirements listed above and EPA has permitted the use of 

CA RFG 2 (California Phase 2 gasoline) for certification for the 2013 model year.8 

Recently, California adopted new requirements for their gasoline certification test 

fuel for nonroad engines. Over the period from 2013-2020, manufacturers must 

transition from CA RFG 2 to a gasoline certification test fuel that contains 10 percent 

ethanol (E10) and has a seven psi RVP (commonly referred to as California Phase 3 

gasoline or CA RFG 3). This new requirement aligns California test fuels with their 

current in-use gasoline. 

Considering this background and recent developments, EPA is proposing to make 

two changes to its current regulatory provisions. First, EPA believes it is appropriate to 

 

8

See EPA Dear Manufacturer Letter CD-12-17(NRSSI), October 29, 2012. 
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propose to extend its current practice of accepting exhaust emission test results for small 

SI engines to include CA RFG 3. For the 2013-2019 model years (inclusive), EPA would 

accept exhaust emission certification data generated using CA RFG 3 test fuel. 

Harmonization with California on test procedures and test fuel requirements for small 

spark-ignition engines has significant value to the engine and equipment manufacturers 

and users of those products. It allows for development and certification of only one 

engine for a given model or application by the manufacturer and allows for greater model 

availability and lower overall cost due to 50-state production. In addition, E10, which is 

used in CA RFG 3, is common in gasoline sold across the U.S. today. Therefore, 

permitting the use of CA RFG 3 in emissions certification would allow test fuel to more 

closely match the in-use fuel used across the U.S. Accounting for the ethanol in the fuel 

is likely to enhance engine emissions in-use durability, because the presence of oxygen in 

the ethanol in the test fuel would need to be accommodated in the engine calibrations. 

This would reduce engine operating temperatures in-use relative to engines calibrated on 

a test fuel without oxygen. 

While EPA is proposing to accept manufacturer use of CA RFG 3 for the 

purposes of testing, EPA is not prepared to propose to accept use of CA RFG 3 as a fully 

permissible replacement test fuel for Indolene. Test data indicate that NMHC+NOx 

exhaust emissions using CA RFG 3 will be comparable relative to results on Federal 

certification fuel. However, due to the presence of an oxygenate (approximately 3 

percent) caused by the inclusion of E10 in CA RFG 3, tested CO emissions would be 

reduced when an engine is tested using CA RFG 3, compared to Indolene which includes 
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no oxygenates (see 40 CFR 1065.710). EPA’s official test fuel is Indolene and the level 

of the CO emission standards for small SI engines (see 40 CFR 1054.103 and 1054.105) 

is based on the use of that fuel. Therefore, EPA cannot fully accept test results using CA 

RFG 3 as showing compliance with EPA CO standards, because CO test emissions 

showing compliance using CA RFG 3 do not guarantee that an engine will be able to 

comply with EPA’s CO standard using Indolene. 

Therefore, EPA proposes to retain the option to conduct any production line, 

confirmatory, and selective enforcement audit (SEA) testing on EPA test fuel as 

specified in 40 CFR 1065.710.9 However, as an option for the manufacturers, to bring 

some uniformity and certainty to the engine development and calibration, emissions 

testing, and emissions durability assessment processes, EPA proposes to use CA RFG 3 

test fuel for any production line, confirmatory, and SEA testing if a manufacturer(s) agree 

to meet a lower CO emission standard. These values, which substantially address the 

effect of oxygenate content on CO emission rates, are 549 g/kW-hr for Classes I and II 

(non handheld engines) and 536 g/kW-hr for Classes III-V (handheld engines). These 

values are the same as California’s current CO emission standards (based on the use of 

CA RFG 2); they are 10-33 percent lower (depending on Class) than EPA’s CO emission 

standards (see 40 CFR 1054.103 and 1054.105) because they account for oxygenate 

content in that fuel. This would not represent a proposed change in stringency, as the 

engine designs and calibration would not change, but CO emissions would decrease due 

 

9 EPA already requires a ten percent ethanol blend for evaporative emissions testing.
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to the oxygenate content of the California test fuel. This proposed option would be 

available for Class I and II marine generators at a CO emission standard of 4.5 g/kW-hr. 

This value was derived based on the ratio of the California CO emission standards to the 

Federal emission standards for other Class I and II marine generators. This option would 

be available on a family-by-family basis for all Classes of small SI engines. We consider 

these CO emission standards to be interim values for purposes of this option only. EPA 

may revise the level of its CO emission standard in the future if we propose to change the 

Federal test fuel specifications. 

Second, EPA proposes to continue accepting exhaust emissions data on CA RFG 

2 after the 2012 model year (see 40 CFR 1054.145(k)). Manufacturers have provided 

data for both handheld and nonhandheld engines showing equivalent exhaust emission

levels between CA RFG 2 and the gasoline specified in 40 CFR 1065.710 (Indolene). 

Furthermore, the move to CA RFG 3 sets in motion a process to eliminate CA RFG 2 

certifications in the future as would have been required under 40 CFR 1054.145(k). 

Thus, to help enable an orderly and cost effective transition, EPA believes it is 

appropriate for us to continue to accept exhaust emission test data using CA RFG 2 for 

certification through the 2019 model year. We would expect engine families certified 

using CA RFG 2 carryover exhaust emission data to meet emissions standards on both 

CA RFG 2 and EPA certification test fuel as specified in 40 CFR 1065.710 for any 

production line, SEA, or confirmatory testing. 

Both of these proposed actions would apply for certification for model years 2013 

to 2019, inclusive. EPA expects to revisit these provisions before 2020 to determine if 
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they should be extended or otherwise modified. The primary EPA program using 

Indolene test fuel and meeting the current EPA emission standards remains in place for 

Federal certification for 2013 and beyond unless and until these provisions are otherwise 

modified.

We are also taking the opportunity to propose to revise the regulatory provision in 

§ 1054.145(c) describing requirements related to altitude kits for handheld engines. We 

adopted those specifications based on the expectation that the Phase 3 exhaust standards 

were unchanged from the Phase 2 exhaust standards. As such, the emission standards do 

not apply at altitudes for which the manufacturer would need to rely on an altitude kit. 

The regulation should therefore be revised to no longer refer to the manufacturer relying 

on an altitude kit “to meet emission standards.” This proposed change in the regulations 

is not intended to change current requirements, but rather simply clarifies the proper 

relationship of the altitude kit to the certified configuration.

V. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review 

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this action is a 

‘significant regulatory action’ because it raises issues that may have a potential effect on 

actions taken or planned by another agency. Accordingly, EPA submitted this action to 

the Office of Management and Budget (OMB) for review under Executive Orders 12866 

and 13563 (76 FR 3821, January 21, 2011) and any changes made in response to OMB 

recommendations have been documented in the docket for this action.

This proposal merely clarifies and corrects existing regulatory language. EPA 
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does not believe there will be costs associated with this rule because the costs in this 

program were previously accounted for under the existing rules (69 FR 38958, June 29, 

2004; 73 FR 59034, October 8, 2008; and 76 FR 57106, September 15, 2011). This 

proposed rule is not anticipated to create additional burdens to the existing requirements. 

As such, a regulatory impact evaluation or analysis is unnecessary.EPA also does not 

expect this rule to have substantial Congressional or public interest.

B. Paperwork Reduction Act

This proposed action does not impose an information collection burden under the 

provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. Burden is defined at 5 

CFR 1320.3(b). The information collection requirements to ensure compliance with the 

provisions in these rules were covered under ICR (2394.02).

The Office of Management and Budget (OMB) has previously approved the 

information collection requirements contained in the existing heavy-duty greenhouse gas 

emissions regulations under the provisions of the Paperwork Reduction Act, 44 U.S.C. 

3501 et seq. and has assigned OMB Control Number 2060–0678. The OMB control 

numbers for EPA’s regulations in title 40 of the Code of Federal Regulations are listed in 

40 CFR part 9.

C. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) as amended by the Small Business 

Regulatory Enforcement Fairness Act of 1996 (Pub. L. 104–121, 110 Stat. 857), 

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 
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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 this rule on small entities, small entity is 

defined as: (1) a small business as defined by Small Business Administration 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.

After considering the economic impacts of this proposed rule on small entities, we 

conclude that this proposed action would not have a significant economic impact on a 

substantial number of small entities. 

This proposal would merely correct and clarify regulatory provisions. In 

particular, as already adopted in the heavy-duty vehicle GHG and fuel efficiency rules, 

EPA is deferring standards for manufacturers meeting the Small Business 

Administration’s definition of small business as described in 13 CFR 121.201. 

There would be no costs and therefore no regulatory burden associated with this 

proposed rule. We have therefore concluded that this proposed rule would not increase 

regulatory burden for affected small entities. We continue to be interested in the 

potential impacts of the proposed rule on small entities and welcome comments on issues 

related to such impacts.

D. Unfunded Mandates Reform Act

This proposed action contains no Federal mandates under the provisions of Title 

II of the Unfunded Mandates Reform Act of 1995 (UMRA), 2 U.S.C. 1531-1538 for 
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State, local, or tribal governments or the private sector. The proposed action would 

impose no enforceable duty on any State, local or tribal governments or the private 

sector. Therefore, this proposed action is not subject to the requirements of sections 202 

or 205 of the UMRA.

This proposed action is also not subject to the requirements of section 203 of 

UMRA because it contains no regulatory requirements that might significantly or 

uniquely affect small governments. 

E. Executive Order 13132: Federalism

This proposed action does not have federalism implications. It would 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. This notice of 

proposed rulemaking merely corrects and clarifies regulatory provisions. Thus, 

Executive Order 13132 does not apply to this proposed action. 

F. Executive Order 13175: Consultation and Coordination with Indian Tribal 

Governments

This proposed action does not have tribal implications, as specified in Executive 

Order 13175 (65 FR 67249, November 9, 2000). This notice of proposed rulemaking

merely corrects and clarifies regulatory provisions. Tribal governments would be 

affected only to the extent they purchase and use regulated vehicles. Thus, Executive 

Order 13175 does not apply to this action. EPA specifically solicits additional comment 

on this proposed action from tribal officials.
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G. Executive Order 13045: Protection of Children from Environmental Health and 

Safety Risks

This proposed action is not subject to Executive Order 13045 (62 FR 19885, April 

23, 1997) because it is not economically significant as defined in Executive Order 12866, 

and because EPA does not believe the environmental health or safety risks addressed by 

this proposed action present a disproportionate risk to children. This notice of proposed 

rulemaking merely corrects and clarifies regulatory provisions. 

H. Executive Order 13211: Actions that Significantly Affect Energy Supply, 

Distribution, or Use

This proposed action is not subject to Executive Order 13211 (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. This notice of proposed rulemaking merely corrects and 

clarifies regulatory provisions. 

I. National Technology Transfer Advancement Act

Section 12(d) of the National Technology Transfer and Advancement Act of 1995 

(“NTTAA”), Public Law No. 104-113, 12(d) (15 U.S.C. 272 note) directs EPA 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 agencies to provide Congress, through OMB, explanations when 

the Agency decides not to use available and applicable voluntary consensus standards. 

This proposed action would slightly expand the use of voluntary consensus 
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standards by adding a reference standard under 40 CFR 1048.105. Other amendments in 

this proposed rule do not involve application of new technical standards. However, the 

underlying regulations in many cases rely on voluntary consensus standards. For 

example, EPA included several voluntary consensus standards in the development of the 

Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and 

Heavy-Duty Engines and Vehicles (76 FR 57106, September 15, 2011).

J. 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. 

EPA has determined that this proposed rule would not have disproportionately 

high and adverse human health or environmental effects on minority or low-income 

populations because it merely would correct provisions for manufacturers to use to 

demonstrate compliance of heavy-duty engines and vehicles. 

VI. Statutory Authority

Statutory authority for the vehicle controls is found in Clean Air Act section 

202(a) (which authorizes standards for emissions of pollutants from new motor vehicles 

which emissions cause or contribute to air pollution which may reasonably be anticipated 
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to endanger public health or welfare), sections 202(d), 203-209, 216, and 301 (42 U.S.C. 

7521 (a), 7521 (d), 7522, 7523, 7524, 7525, 7541, 7542, 7543, 7550, and 7601).

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, Labeling, 

Motor vehicle pollution, Reporting and recordkeeping requirements.

40 CFR Part 1036

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 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
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Environmental protection, Administrative practice and procedure, Air pollution control, 

Confidential business information, Imports, Labeling, Penalties, Reporting and 

recordkeeping requirements, Warranties.

40 CFR Part 1042

Environmental protection, Administrative practice and procedure, Air pollution control, 

Confidential business information, Imports, Labeling, Penalties, Vessels, Reporting and 

recordkeeping requirements, Warranties. 

40 CFR Part 1048

Environmental protection, Administrative practice and procedure, Air pollution control, 

Confidential business information, Imports, Incorporation by reference, Labeling, 

Penalties, Reporting and recordkeeping requirements, Warranties.

40 CFR Part 1054

Environmental protection, Administrative practice and procedure, Air pollution control, 

Confidential business information, Imports, Labeling, Penalties, Reporting and 

recordkeeping requirements, Warranties.

40 CFR Part 1065 and 1066

Administrative practice and procedure, Air pollution control, Reporting and 

recordkeeping requirements, Research.
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40 CFR Part 1068

Environmental protection, Administrative practice and procedure, Confidential business 

information, Imports, Motor vehicle pollution, Penalties, Reporting and recordkeeping 

requirements, Warranties.
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Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments

Dated: _______________________

_____________________________________________________

Bob Perciasepe, 

Acting Administrator