Light-Duty Greenhouse Gas
 

Questions and Answers

Office of Transportation and Air Quality 

EPA-420-F-12-005 

January 2012 
 

 

 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012 

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

1. Application for Certification

1.1 

Application for 

Certification ­

Listing part 

numbers in the 

Par 2 

Application 

86.1844-01(e)(1) 

Should the following components be listed on the 

emission related parts list (Part 2 application) for future 

MY vehicles due to GHG regulation? 

• A/C system (including all sensors and actuators) 

• Actuator of flexible aerodynamic devices 

• Sensors and actuators of a cyclinder deactivation 

system 

• Components of an engine idle start/stop system 

For 2012 and later model years, part numbers of GHG emission-related components 

and AECDs used to comply with CO2 (CREE), CH4, N2O emission standards are 

required to be listed in the Part 2 application; ref. 86.1844-01(e). For 2009-2011 model 

years, manufacturers may include part numbers of GHG emission-related components 

and AECDs in the early credit report required by 86.1867-12(e), in lieu of including part 

numbers in the 2009-2011 Part 2 applications. Manufacturers may reference the 

service manual of the vehicle in lieu of listing part numbers for sensors and actuators 

for A/C systems, cylinder deactivation systems, stop-start systems, etc. provided the 

system is listed in the applicable Part 2 application or early credit report. Note that the 

service manual is required to be contained in the Part 2 application per 86.1844­

01(e)(5). 

1.2 

Application for 

Certification ­

Listing GHG 

AECDs in the 

Part 1 Application 

86.1803-01 

For criteria pollutants, 

manufacturers are required to list 

AECDs in the Part I application. 

Manufacturers are required to list 

part numbers of emission related 

components in the Part II 

application. Manufacturers are 

required to cover these AECDs 

under the defect warranty. 

What is EPA’s policy regarding AECD classification for 

GHG? 

Auxillary emission control devices (AECDs) are not discussed in the preamble 

to the GHG final rule or the Response to Comments document. Manufacturers 

should use good engineering judgment to determine which design elements for 

greenhouse gas control meet the definition of an AECD outlined in 86.1803. 

See EPA answer to question 1.1, above, for additional information about listing 

part numbers of emission-related components and AECDs in the Part 2 

application. 

2. Credits - A/C Efficiency 

2.1 

A/C Efficiency 

Credits - A/C Idle 

Test 

86.165-12 

The preamble to the final rule (75 FR 

25431) states that "EPA expects to 

continue working with industry, the 

California Air Resources Board, and 

other stakeholders to move toward 

increasingly robust performance tests 

and methods for determining the 

efficiency of mobile A/C systems and the 

related impact on vehicle CO2 

emissions, including a potential adapted 

SC03 test." 

Does EPA intend to modify the idle test procedure for 14MY 

and after certification? 

If EPA will not change during above phase, is the projected 

timing of new test procedure introduction at post 2016MY? 

EPA proposed several changes to the 2014-2016 A/C idle test requirements in the lightduty 2017 and later GHG/CAFE proposed rule; ref. 76 FR 74854, Dec 1, 2011. 

Proposed changes are outlined on pages 76 FR 75006-07 of the preamble to that 

proposed rule, including: 

1) revising the A/C idle test CO2 threshold values which are used to qualify for menubased A/C efficiency credits; 

2) revising ambient temperature and humidity test conditions of the A/C idle test; and 

3) allowing manufacturers to optionally qualify to use menu-based A/C efficiency credits 

by reporting CO2 and other information on a new transient A/C test (the AC17 test) in 

lieu of performing the A/C idle test. The AC17 test is described in the proposed 

regulations at 86.167-14. 

2.2 

A/C Efficiency 

Credits - A/C Idle 

Test 

86.165-12(d)(4) 

Measure and record the continuous CO2 

concentration for 600 seconds. Measure 

the CO2 concentration continuously 

using raw or dilute sampling procedures. 

Multiply this concentration by the 

continuous (raw or dilute) flow rate at 

the emission sampling location to 

determine the CO2 flow rate. Calculate 

the CO2 cumulative flow rate 

continuously over the test interval. This 

cumulative value is the total mass of the 

emitted CO2. 

This requires us to have modal mass 

method. However, our certification 

equipment does not have ability for 

modal mass method. 

Is it acceptable to use CVS method as an alternative to modal 

mass method? 

The AC idle test is discussed in the preamble to the final rule, pages 75 FR 25429-31. 

Yes, it is acceptable to use a CVS system to measure CO2 emissions during the A/C 

idle test. EPA revised the regulations in the 2013 FE Labeling final rule (76 FR 39478, 

July 6, 2011) to clarify this requirement, adding the following sentence to the provisions 

of 40 CFR 86.165-12(d)(4): "Alternatively, CO2 may be measured and recorded using a 

constant velocity sampling system as described in §§ 86.106-96(a)(2) and 86.109-94." 

2.3 

A/C Efficiency 

Credit 

Calculation 

86.1866-12(c)(3) 

AC Efficiency Credit via Idle Test – Credits are provided if 

CO2 increase is less than 21.3 g/min. If a vehicle is not 

equipped with AC at all, can we subtract 21.3 g/min? 

No, the GHG idle test and air conditioning credit provisions are not applicable to 

vehicles not equipped with air conditioning. Please see the provisions of 40 

CFR 86.1866-12(c)(3). Those provisions provide that air conditioning efficiency 

credits generated for an air conditioning system are based on the “Production” 

of vehicles equipped with an air conditioning system where “Production = The 

total number of passenger cars or light trucks, whichever is applicable, 

produced with the air conditioning system to which the efficiency credit value 

from paragraph (c)(2) of this section applies." [Emphasis added.] 

Page 1 
 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

A/C efficiency credit requirements are discussed in the preamble of the final 

rule, pages 75 FR 25424-25 and 25427-31. 

Background: First, for use of A/C efficiency credits, manufacturers are 

sometimes required to submit an engineering analysis to EPA for approval (for 

closed-loop and open-loop systems which default to recirculated air at ambient 

temperatures of 75deg F or higher). Deviations from the 75deg F are allowed if 

accompanied by an engineering analysis. For example, EPA may approve 

2.4 

A/C Efficiency 

Credits which 

require EPA 

approval 

86.1866-12((c)(1)(iii); 

86.1866-12((c)(1)(viii); 

86.1866-12((c)(6)(v) 

How do we demonstrate items for which demonstration is 

required for AC efficiency credits? Does EPA plan to 

publish a guidance letter in the near future on these 

issues? 

credits for A/C systems which default to outside air for 10 seconds every 3 

minutes to reduce cabin CO2 levels. Second, if using A/C efficiency credits for 

1) improved condensers and/or evaporators and 2) oil separators, 

manufacturers are required to submit an engineering analysis to EPA . Please 

see EPA answers to questions 2.7 and 2.8, below. 

Manufacturers should submit any required engineering analyses to EPA in a 

letter to their EPA certification team member prior to or concurrently with the premodel year report. 

EPA has no plans to publish a guidance letter on this issue. 

2.5 

A/C Efficiency 

Credits - A/C 

Idle Test 

86.165-12; 

86.1866-12(c)(5) 

Testing of vehicles that have dual 

AC systems, or front and rear seat 

cooling systems, or cooler box 

options, are not addressed in the 

regulation. 

1. Should the rear A/C system be operational when 

conducting the A/C idle test? 

2. Is 33% optional equipment criteria applicable to A/C 

idle test vehicles? 

The AC idle test is discussed in the preamble to the final rule, pages 75 FR 

25429-31, and outlined in the regulations at 86.165-12 and 86.1866-12(c)(5). 

1. For dual A/C systems, systems with cooler box options, systems with driveroperated ECO buttons, etc., the A/C idle test should be conducted with the A/C 

system in the default (key-off) mode. For example, if the A/C system normally 

defaults on key-off to front A/C only, the A/C idle test should be conducted with 

the front A/C on (and the rear A/C off). Conversely, if the A/C system does not 

default on key-off to front A/C only, the A/C idle test should be conducted with 

both front and rear A/C on. 

2. For optional A/C equipment, manfacturers should contact their EPA 

certification representative and obtain EPA approval prior to conducting the test. 

The details of A/C idle test procedure for PHEVs, vehicles equipped with stopstart system and new technology systems will be addressed in future guidance. 

2.6 

A/C Efficiency 

Credits - Default 

to Recirculated 

A/C mode 

86.1866-12(c) 

A/C Default to re-circulated air 

mode: 

Per the regulation, AC-CO2 credits 

would not be applicable for a 

system, as described below: 

“When system does not default to 

re-circulated air with closed-loop 

control of the air supply, but 

operators can select more efficient 

Does EPA allow CO2 credit on applications which 

activate a more efficient AC operation mode using recirculated air with closed-loop control of the air supply? 

(For example, ECO type switch.) 

A/C efficiency credit requirements are discussed in the preamble of the final 

rule, pages 75 FR 25424-25 and 25427-31. The provisions of 86.1866-12(c) do 

not allow EPA to approve special A/C efficiency credits (or partial credits) on a 

case-by-case basis for A/C systems which are not listed in 86.1866-12(c) (or for 

variations of A/C systems which are listed in 86.1866-12(c)(1)). Thus, A/C 

systems would receive no credit if the driver-operated ECO button was 

designed not to default to recirculated air upon key-off. Conversely, A/C 

systems would receive full credit if the A/C system were designed to default 

AC operation with re-circulated air 

with closed-loop control of the air 

supply.” 

upon key-off to recirculated air. 

Also see EPA answer to question 2.5, regarding the A/C idle test. 

Page 2 
 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

2.7 

A/C Efficiency 

Credits - 

Improved 

Condensors 

and/or 

Evaporators 

86.1866-12((c)(6)(v) 

Demonstration, certification and 

approval process are unclear and 

2012MY certification timing 

presents a concern because 

2012MY certification is already 

underway. 

1. When and how should manufacturers demonstrate 

COP of the system is improved higher than 10%? 

2. Regarding AC system which achieves 10% or higher 

COP improvement, will EPA consider additional credit 

beyond 1.1g? 

A/C efficiency credit requirements are discussed in the preamble of the final 

rule, pages 75 FR 25424-25 and 25427-31. 

1. See EPA answer to question 2.4 above. To receive the 1.1 g/mile credit for 

improved condensors and/or evaporators, manufacturers should follow the 

procedure outlined in 86.1866-12((c)(6)(v) (which requires the manufacturer to 

submit an engineering analysis each model year for EPA approval). The 

engineering analysis should compare the coefficient of performance (COP) of 

the current model year system to the COP of the previous generation A/C 

system used in that vehicle model or platform (where COP is measured 

according to SAE procedure J2765). For example, if a new generation A/C 

system goes into production in 2012-2014 model years, the 2012-2014 

engineering analyses should compare the COP of the 2012-2014 system to the 

COP of the 2011 system. Similarly, if a new generation A/C system goes into 

production in the 2015 model year, the 2015 engineering analyses should 

compare the COP of the 2015 system to the COP of the 2012-2014 system. 

2. The provisions of 86.1866-12(c)(6)(v) do not allow EPA to approve special 

A/C efficiency credits on a case-by-case basis for A/C systems which have a 

COP improvement greater than 10%. 

2.8 

A/C Efficiency 

Credits for 

Improved Oil 

Separator 

86.1866-12((c)(1)(viii) 

86.1866-12(c)(6)(vi) 

Demonstration, certification and 

approval process are unclear and 

2012MY certification timing 

presents a concern because 

2012MY certification is already 

underway. 

When and how should manufacturers demonstrate Oil 

Separator effectiveness? 

(i.e. At least 50% of the oil entrained in the oil/refrigerant 

mixture exiting the compressor returns it to the 

compressor housing or ......) 

See EPA answer to question 2.4 above. A/C efficiency credit requirements are 

discussed in the preamble of the final rule, pages 75 FR 25424-25 and 25427­

31. To receive the 0.6 g/mile credit for an improved oil separator, 

manufacturers should follow the procedure outlined in 86.1866-12((c)(1)(viii) 

(which requires the manufacturer to submit an engineering analysis each model 

year for EPA approval). 

The engineering analysis should compare the current model year oil control 

system to the to the "baseline" oil control system used on the previous 

generation A/C system used in that vehicle model or platform, as discussed in 

question 2.7 above. For example, a manufacturer could measure the oil 

circulation rate in the baseline configuration, and then compare it to the oil 

circulation rate of the new configuration. As outlined in 86.1866-12(c)(6)(vi), if 

the new configuration eliminates 50% of the oil that was circulating in the 

baseline system, vehicles equipped with the new oil control system would qualify 

for the 0.6 gr/mile "oil separator" credit. 

Page 3 
 

 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

2.9 A/C Efficiency 

Credits - A/C 

Idle Test 

Procedure for 

vehicles 

equipped with 

stop-start 

systems 

86.1866-12(c)(5); 

86.165-12 

1. Starting with MY 2014, A/C efficiency credits can only 

be received if a certain efficiency is proven using a 

special engine idle test procedure described in §86.165­

12. We are wondering how this procedure would work 

with vehicles using an engine Start/Stop system. In this 

case, the engine will not run in the first part of 10 min with 

A/C off but will run in the second 10 min with A/C on, 

which will always result in raising CO2 emissions above 

21.3 g/min which means that no credit will be received. 

Therefore, we think that for vehicles with an engine 

Start/Stop system, the system should be deactivated 

during the whole procedure (10 min idle with A/C off and 

10 min idle with A/C on). Another option could be if the 

approach for compressors driven by electricity is 

transferred to vehicle with Start/Stop systems. In this 

case, the system is deemed to be energy efficient if the 

engine is stopped for a period off at least 2 minutes (p. 

1353). 

2. Regarding BEVs, it is our understanding that the 

efficiency requirement is always met because the traction 

engine is always off during "idle." 

3. What about PHEVs? Must the engine off period of 2 

min be demonstrated in the charge depleting or in the 

charge sustaining mode? 

The AC idle test is discussed in the preamble to the final rule, pages 75 FR 

25429-31. For background information, please see EPA answers to questions 

2.1, 2.2, 2.3 and 2.5 above. Especially see EPA answer 2.1 above regarding 

proposed changes to the 2014-2016 A/C idle test requirements. 

1. Idle test requirements for vehicles equipped with stop-start systems will be 

addressed in future EPA guidance. Our initial thoughts are that EPA approval 

will be required and that each stop-start design will be evaluated on a case-bycase basis (because each stop-start design is likely to have different operation 

characteristics and calibration parameters). 

2. EPA agrees that battery electric vehicles would meet the idle testing 

requirement outlined in 86.1866-12(c)(5)(iv) by design (and thus would not be 

required to conduct the idle A/C test). 

3. Idle test requirements for PHEVs will be addressed in future EPA guidance. 

3. Credits - A/C Leakage 

3.1 

A/C Leakage 

Credits - 

Alternative 

Refrigerants 

86.1866-12(b) 

GHG credit for refrigerant with low 

GWP is defined in the regulation 

and GHG standards were based 

on availability of available 

alternative refrigerants (i.e. HFO1234yf). 

Currently HFO-1234yf is costly and has limited availability. 

What is EPA’s role in ensuring availability of these low 

GWP alternative refrigerants? 

Title IV refrigerant regulations are discussed in the preamble to the final rule 

(pages 75 FR 25431-32) and in the preamble to the 2017 and later light-duty 

GHG/CAFE proposed rule, (pages 76 FR 75002-05, Dec 1, 2011). EPA's 

Stratospheric Protection Division; Office of Air Programs (located in 

Washington, D.C.) is responsible for approving new refrigerants. 

4. Credits - General Questions 

4.1 

Credits - Good 

Faith Effort to 

Purchase 

Credits 

86.1801(k)(3) 

"To be exempted from the 

standards....., the manufacturer 

must submit.....and documentation 

of good-faith effort to purchase 

credits from other manufacturers." 

Obtaining GHG credits. Proof of effort expended to obtain credits – due diligence - what 

is expected of an small volume manufacturers to prove this? 

Conditional exemption from greenhouse gas requirements is discussed in the preamble 

of the final rule, pages 75 FR 25419-21 and 75 FR 25483. This question will be 

addressed on a case-by-case basis for each small volume manufacturer and possibly in 

future EPA guidance. 

4.2 

Credit 

Calculations ­

Vehicle Lifetime 

Miles 

86.1865-12(k)(4); 

86.1866-12(b), (c), Final GHG rule. Credit/debt calculation. 

For credit/debit calculation we believe the 195,264 miles 

assigned lifetime is unrealistic and creates an unnecessary 

burden. Does (we suggest) a small volume manufacturer have 

the opportunity to justify a realistic vehicle lifetime based on 

customer usage profiles? 

The basis for the 195,264 lifetime VMT for cars and 225,865 for trucks is outlined on 

pages 4-76 and 5-35 of the EPA Response to Comments document available at 

http://www.epa.gov/otaq/climate/regulations.htm#1-1. The car and truck lifetime VMT 

mileages are used only to facilitate credit transfers between car and truck credit 

programs. Thus, the important feature of these VMT values is the ratio of the car and 

truck lifetime VMT values, and not the absolute value of the lifetime VMT mileages. The 

absolute values of the car and truck lifetime VMT values, by themselves, do not create 

any additional burden for manufacturers. For this reason, regulations do not provide 

small volume manufacturers with an oportunity to use alternative lifetime VMT values. 

Page 4 
 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

5. Durability Requirements 

5.1 

Durability ­

Alternative DFs 

for N2O, CH4, 

CREE 

86.1823-08(m)(2)(iii)&(3) 

(m)(2)(iii) For the 2012 through 2014 

model years only, manufacturers may 

use alternative deterioration factors. For 

N2O, the alternative DF to be used to 

adjust FTP and HFET emissions is the 

additive or multiplicative DF determined 

for (or derived from, using good 

engineering judgment) NOX emissions 

according to the provisions of this 

section. For CH4, the alternative DF to 

be used to adjust FTP and HFET 

emissions is the additive or 

multiplicative DF determined for (or 

derived from, using good engineering 

judgment) NMOG or NMHC emissions 

according to the provisions of this 

section. 

Because additive deterioration factors 

(DFs) are absolute values of emission 

deterioration for each emission 

constituent, it is difficult to apply an 

additive DF for an emission 

constitutuent as it is to other emission 

constituent, which has a different 

emission standard. 

We think we need compensation when we use an additive DF 

for other emission constituents with different emission 

standards. Is this acceptable? For example of NOx and N2O, 

additive DF for N2O = additive DF for NOx/(NOx std./N2O std.) 

We agree with the comment and revised 86.1823-08(m)(2)(iii) in the 2013 FE Labeling 

final rule (76 FR 39478, July 6, 2011). The regulation changes are shown in redline text 

in column 4. Note that EPA inadvertantly overwrote those changes in the Heavy-duty 

GHG final rule (76 FR 57106, Sept 15, 2011). As a result, the language in column 4 is 

now contained in the light-duty 2017 and later GHG/CAFE proposed rule; ref. 76 FR 

74854, Dec 1, 2011. 

We also revised paragraph 86.1823-08(m)(3) in the Heavy-duty GHG final rule (76 FR 

57106, Sept 15, 2011) to clarify that 1) manufacturers may determine city and highway 

CREE (or OCREE) DFs instead of determining DFs for each individual constituent that 

is contained in CREE (or OCREE); and 2) manufacturers may use the applicable FTP 

(city) DF for the highway test for an emission constituent. Note that the provision to use 

the FTP DFs for highway tests does not apply to the alternative method of determining 

CO2 DFs outlined in the provisions of 86.1823-08(m)(1)(iii). 

For example, paragraph (m)(3) was revised in the Heavy-duty GHG final rule to read in 

part: "....FTP-based deterioration factors shall be determined for carbon-related 

exhaust emissions (CREE), hydrocarbons and CO according to the provisions of 

paragraphs (a) through (l) of this section. The FTP-based deterioration factor shall be 

used to determine full useful life emissions for both the FTP (city) and HFET (highway) 

test cycles. The manufacturer may at its option determine separate deteriorationfactors 

for the FTP and HFET test cycles...." 

5.2 

Durability 

demonstration 

procedures for 

GHG emission 

standards. 

86.1823-08(m) Timeline for demonstration. 

1. Because 2012MY durability has begun, is it acceptable 

to demonstrate by MY report timing (90 days after the end 

of 2012MY)? 

2. Applicability: Is this applicable to AC components and 

system, off-cycle technology and so on during 2009­

2011MY? 

3. Demonstration Procedure: When and how should AC 

durability demonstration be performed? 

4. Will EPA provide standard procedures for eligible AC 

and off-cycle technologies, or will EPA require 

manufacturers to consider original durability procedure 

and get EPA's approval before getting AC credit 

approval? 

1. No, not allowed by current regulations. 

2. Durability requirements for air conditioning systems and components (and 

other credit-generating components) are outlined in the preamble to the final 

rule (page 75 FR 25425) and in 40 CFR 86.1823-08(m)(4) which reads as 

follows: "Manufacturers will attest to the durability of components and systems 

used to meet the CO2 standards. Manufacturers may submit engineering data 

to provide durability demonstration." Thus, deterioration factors are not 

applicable to emission-related components used to obtain A/C leakage or A/C 

efficiency credits . 

3. Durability demonstration for A/C and other credit components should be 

performed prior to certification. The attestation required by 86.1823-08(m)(4) 

should be included in the initial Part 1 application for certification. 

4. EPA will not provide standard durability procedures for eligible AC and offcycle technologies. Durability requirements for CO2 (CREE), N2O, CH4, 

methanol, ethanol, HCHO, and C2H4O emissions are addressed in 86.1823­

08(a) through (m), similar to other criteria pollutants. See parts 2 and 3 of this 

question for durability requirements for credit components such as A/C leakage, 

A/C efficiency and off-cycle components. 

6. Early Credits (2009-2011 Model Years) 

6.1 Early A/C Credit 

Provisions 86.1867(b)(2) 

Manufacturers that are required to 

comply with California greenhouse gas 

requirements in model years 2009-2011 

(for California and section 177 states) 

may not generate early air conditioning 

credits for vehicles sold in California and 

the section 177 states as determined in 

paragraph (a)(2)(i) of this section 

As you know, most manufacturers 

have to comply with Pavley1 during 

2009-2011MY. [EPA comment: Small 

& intermediate mfrs don't have to meet 

CARB 2009-2011 GHG requirements.] 

Then, most manufacturers cannot 

obtain in A/C credit if they select 

pathway2, right? And it's strange that 

pathway1 can generate A/C credit, 

which uses Pavley1's standard. 

EPA revised the regulations in the 2013 FE Labeling final rule (76 FR 39478, July 6, 

2011) deleting this requirement. The provisions of 40 CFR 86.1867(b)(2) were revised 

to read: 

"Manufacturers that select Pathway 4 as described in paragraph (a)(4) of this section 

may not generate early air conditioning credits for vehicles sold in California and the 

section 177 states as determined in paragraph (a)(2)(i) of this section. Manufacturers 

not participating in one of the early fleet average credit pathways described in this 

section may generate early air conditioning credits only for vehicles sold in states other 

than in California and the section 177 states as determined in paragraph (a)(2)(i) of this 

section." 

Page 5 
 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

Early credit provisions are outlined in the preamble of the final rule (75 FR 25441-44) 

and in 86.1867-12. Averaging, banking and trading provisions are outlined in the 

preamble of the final rule (75 FR 25412-14) and in 86.1865-12(k). If a manufacturer 

6.2 Early Credit 

Trading 

86.1865-12(k); 86.1867­

12(a)(1)(vi), (a)(2)(ii), 

(a)(3)(viii), (a)(4) 

Final GHG rule. Early Credit Trading 

Are manufacturers allowed to trade early credits (generated 

during 2009-2011MY) to other OEM’s? 

selected pathways 1, 2, or 3, credits earned in 2009 may not be traded to other mfrs 

(including A/C leakage, A/C efficiency, advanced technology, and off-cycle credits), ref. 

75 FR 25442. All other credits may be traded to other mfrs (ref. 86.1865-12(k)(7) and 

75 FR 25414) subject to the limitations of 86.1865-12(k)(9); reporting requirements of 

86.1865-12(l)(2), etc. Note that the provisions of 86.1865(k)(9)(iv) prohibit a 

manufacturer from trading credits which will result in the manufacturer having a debit at 

the end of the model year that the credit was traded. 

Pathway 1 states that "Total U.S. For Pathway 1, we believe total U.S. production should be 

Early credit provisions are outlined in the preamble of the final rule (75 FR 

25441-44) and in 86.1867-12. Currently the introductory text in paragraph of 

86.1867 reads in part "The terms "sales" and "sold" as used in this section shall 

mean vehicles produced and delivered for sale in the states and territories of 

6.3 

Early Credit 

Provisions ­

Production vs. 

Actual Sales Data 

86.1867-12 introductory 

paragraph and 86.1867­

12(a)(1) 

model year sales data will be used, 

instead of production data," as 

well as the preamble stating, 

"...manufacturers using Pathway 1 

or 2 will use year-end car and truck 

also allowed, as this is consistent with the CAFE 

calculation procedure. 

Can we use total U.S. production for early credit 

calculation of pathway 1? 

the United States." This introductory paragraph conflicts with paragraph 

86.1867-12(a)(1)(iii)(A) which reads "Total U.S. model year sales data will be 

used, instead of production data." 

EPA agrees that for Pathways 1, 2, 3 and 4, tracking production data (instead of 

sales in each category.” sales data) is an acceptable method of tracking vehicles delivered to the point of 

first sale (which is the dealer). Therefore, EPA revised the regulations in the 

2013 FE Labeling final rule (76 FR 39478, July 6, 2011) , deleting the 

requirement to use sales data in paragraph 86.1867-12(a)(1)(iii)(A). 

7. High Altitude Requirements 

Our understanding is that CO2, N2O 

High altitude greenhouse gas requirements are discussed in the preamble of the final 

rule on page 75 FR 25484. CO2/CREE, N2O, and CH4 standards are all altitude 

standards, ref 86.1810-09(f). In-use standards for high altitude testing are outlined in 

86.1818(d). 

As background information for this question, EPA compared high & low altitude IUVP 

CO2 data. Out of 102 matching pairs of high and low altitude IUPV vehicles, three high 

alt IUVP vehicles had CO2 levels 10% higher than the matching low altitude IUPV 

vehicle. 

7.1 High Altitude 

Standards 

86.1818(d); 

86.1841(a)(3) 

86.1810-09(f),(2) 

and CH4 must comply with high 

altitude standards similar to other 

emission pollutants. Is our 

However, how should we prove the compliance with CO2 high 

altitude standards because in-use CO2 standard is decided as 

1.1 x {New vehicle CO2}. 

For certification N2O and CH4 compliance, manufacturers have the option to test a 

vehicle at high altitude or submit a compliance statement in the application in lieu of 

understanding correct? testing. However, the compliance statement does not apply to CO2 (CREE) because 

there are no CO2 (CREE) certification standards. See EPA answer to question 7.2 

regarding the requirement to submit an engineering evaluation indicating that for N2O, 

CH4 and CO2 (CREE), common calibration approaches are used at high altitude. 

For in-use, the IUVP vehicle tested at high altitude must pass the in-use CO2 standard, 

which is the city/highway combined CO2 (CREE) for the matching subconfiguration 

represented with test data (or model type CO2 (CREE) if the IUVP configuration does 

not match any tested configuration) multiplied by a factor of 1.1. 

Page 6 
 

 

 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

7.2 High Altitude 

Standards 

1810-09 (f) 

86.1829-01(b)(1)(ii) 

86.1810-09 (f) Altitude 

requirements... 

(2) For vehicles that comply with the 

cold temperature NMHC 

standards... and the CO2, N2O and 

CH4 exhaust emission standards 

described in 86.1818-12, 

manufacturers must submit an 

engineering evaluation indicating 

that common calibration approaches 

are utilized at high altitudes (except 

when there are specific high altitude 

calibration needs to deviate from low 

altitude emission control practices). 

Any deviation from the low altitude 

emission control practices must be 

included in the AECD descriptions 

submitted at certification. Any AECD 

specific to high altitude must require 

engineering emission data for EPA 

evaluation to quantify any emission 

impact and validity of the AECD. 

Our understanding is that CO2, 

N2O and CH4 emissions also have 

to meet compliance with high 

altitude standards, similar to the 

other emission constituents. 

1. Can EPA confirm this understanding? If this 

understanding is correct, can EPA clarify how a 

manufacturer should prove CO2 high altitude compliance 

since the in-use CO2 standard will be determined as 1.1 x 

New vehicle CO2. 

2. EPA answered this on slide 68, bullet3, subbullet 1-­

"Engineering evaluation required in Part 1 for CO2, CH4, 

N2O: Common calibration approaches are used at high 

altitudes." However, since EPA already requires 

compliance with emission standards at altitude, there is 

no need for a further compliance statement that the 

calibration approaches are the same at high altitude as at 

low altitude. Indeed, the opposite may be true to ensure 

compliance with emission standards at high altitude. We 

recommend this subbullet be deleted. 

High altitude greenhouse gas requirements are discussed in the preamble of 

the final rule on page 75 FR 25484 and in 86.1810-09(f). 

1. EPA agrees with your understanding that CO2/CREE, N2O, and CH4 

standards are all altitude standards, ref 86.1810-09(f). The second part of this 

question is answered in question 7.1, above. 

2. EPA believes that it is appropriate to require in the Part 1 application the high 

altitude compliance statement required by 86.1829-01(b)(1)(ii) and an 

engineering evaluation that common calibration approaches are used at high 

altitude required by 86.1810-09(f). However EPA agrees with the comment that 

sometimes different high altitude calibration approaches may be needed. 

Therefore, EPA intends to clarify the provisions of 86.1810-09(f) (as shown in 

the redline text in column 4 at the next opportunity.

 In those cases where common calibration approaches are different at high and 

low altitude, the high-altitude calibration approach should be included in the 

AECD description in the Part 1 application as required by 86.1844-01(d)(11). 

EPA would consider the requirement to use common calibration approaches at 

high altitude to be satisfied in cases were a vehicle used similar calibrations, 

software and elements of design at low and high altitudes during hot/cold starts, 

hot/cold ambient conditions, hot/cold engine operation, etc. Calibration 

approaches, for example, would include (but are not limited to) idle speeds, 

spark advance, air/fuel ratio, valve timing, transmission shift and lock-up 

schedules and EGR calibration strategy. For hybrid vehicles, calibration 

approaches would also include the electric operation strategy of the vehicle. 

8. In-Use Requirements 

8.1 

In-Use 

Requirements ­

Emission 

Related Defect 

Definition 

85.1902(b)(2) 

"A defect in the design, materials, or 

workmanship in one or more 

emissions control or emissionrelated parts, components, systems, 

software or elements of design which 

must function properly to assure 

continued compliance with vehicle 

emission requirements, including 

compliance with CO2, CH4, N2O, 

and carbon-related exhaust 

emission standards." 

The preamble describes this 

regulatory change (that is, the 

adding of paragraph 2) as: (1) A 

minor clarification, (2) Effective 

beginning with the 2012 model 

year and (3) Requiring the 

reporting of defects related to GHG 

emissions. 

Do you interpret this change as 1) preserving the existing 

definition from the 1977 rule that defines an emissionrelated defect and 2) expanding the definition also to 

include defects that affect GHG emissions? I am 

concerned that some may misinterpret this new regulation 

to suddenly require the reporting of defects that do not 

affect emissions (Appendix VIII is not mentioned, and the 

"assured continued compliance" phrase only adds words 

to describe the part, not what the defect could upset), and 

to create a new definition of a defect related to non-GHG 

emissions (that is, believing the original definition in 

paragraph 1 is obsolete via a broader definition in 

paragraph 2). We are happy to offer several ways to 

improve the clarity, either by tweaking very few words, or 

re-writing the section. Whatever the outcome, I believe it 

would be helpful if the regulatory text in paragraph 2: 

EPA intended to preserve the existing definition from the 1977 rule that defines 

an emission-related defect and expand the definition also to include defects that 

affect GHG emissions. EPA revised the regulations in the 2013 FE Labeling 

final rule (76 FR 39478, July 6, 2011) to amend the definition contained in 40 

CFR 85.1902 (b) (2) as follows: 

"A defect in the design, materials, or workmanship in one or more emissions 

control or emission-related parts, components, systems, software or elements of 

design which must function properly to assure continued compliance with 

greenhouse gas emission standards." 

Required reporting for defects that affect compliance 

Related specifically to 2012 and later GHG emission 

defects (preserving paragraph 1 for non-GHG related 

defects). 

8.2 

In-use 

Standards for 

PHEV/EV 

vehicles 

86.1866-12(a)(2) 

How will the 1.1 in-use standard be applied to EVs and 

PHEVs? We assume it won’t affect EVs up to the 

200K/300K 0 g/m cap...but, how about after the cap? 

How about PHEVs? 

The 1.1 in-use standard will apply to all of your product line subject to GHG--­

please read the regulations and preamble for the details of what in-use standard 

applies to what vehicles. Of course, EVs, fuel cell vehicles and the electric 

portion of PHEVs are entitled to use zero CREE emissions---so there won't be 

much point in EPA performing confirmatory testing of EVs and fuel cell vehicles-­

or the electric portion of PHEVs. After a manufacturer exceeds the production 

volume limits in 86.1866-12(a)(2), the 1.1 standard will be determined/applied to 

EVs, PHEVs and fuel cell vehicles similar to the way it is determined/applied to 

conventional vehicles. 

Page 7 
 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

8.3 

In Use 

Requirements ­

Emission 85.1902 

Emission Related Defect Definition: 

“A defect in the design, materials, or workmanship in one 

or more emissions control or emission‐related parts, 

components, systems, software or elements of design 

which must function properly to assure continued 

compliance with vehicle emission requirements, including 

compliance with CO2, CH4, N2O, and carbon‐related 

exhaust emission standards;” 

See answer 8.1 above regarding the Emission Related Defect Definition. 

1. Manufacturers should treat each claim or failure separately, except for system 

failures (e.g. when three components in the cylinder deactivation system fail and 

all have more than 25 failures). 

Related Defect 

Definition 1. Would EPA require to count each claim or failure of a 

system or part which is in the vehicle to reduce CO2 as 

an emission related defect? 

2. Even if the system results in small CO2 benefit (less 

than 10%) and the CO2 standard will not be failed? 

2. As is the case with current defect reporting requirements, manufacturers are 

required to report defects in emission-related parts, components, systems, 

software or elements of design; regardless of whether the defect causes the 

vehicle to exceed applicable emission standards. 

8.4 In-Use CO2 

(CREE) 

Standards ­

Based on Data 

Substitution & 

Analytical Data 

86.1818-12(d) When establishing/calculating inuse CO2 standards, EPA says that 

the value should be based on the 

subconfiguration value and if no 

subconfiguration value is available, 

the value should be based on 

model type. 

When determining whether data exists for the 

subconfiguration, are we only to consider actual test data 

or do we also include data substitutions and/or analyticallyderived data? 

In-use standards are discussed in the preamble to the final rule, page 75 FR 

25476-77 and in the provisions of 86.1818-12(d). As discussed in those 

provisions, the GHG data used to determine in-use standards include all 

carline/subconfiguration data used to demonstrate compliance with the CO2 

(CREE) fleet average emission standards, including data substitution data, 

engine code equivalency data, analytically derived CREE data, etc. 

9. Miscellaneous Questions 

9.1 Miscellaneous ­

CAFE 600.512-08(c)(8) CAFE Model year report CAFE footprint standards calculator. 

Where does the EPA reformed CAFE calculator fit into this 

ruling? 

The reformed CAFE footprint Calculator (Excel spreadsheet) is currently used to 

determine the CAFE standards for 2008-2016 reformed CAFEs. EPA supplied this 

calculator (entitled EPA 2008-2016 Reformed CAFE STD Calculator.9-30-10.xls) to the 

Industry in October, 2010. EPA anticipates that the Excel spreadsheet calculator will be 

replaced by EPA's Verify data base system for 2012 model year CAFEs (and 2012 

CAFE/greenhouse gas calculations). 

9.2 

Miscellaneous ­

CREE 

(Intermingling of 

CO2 and CREE 

terms) 

86.1803-01 and 600.002­

08 - Definition of Carbonrelated exhaust 

emissions 

Why are CO2 equivalents mentioned sometimes and 

sometimes CREE? 

The intermingling of CO2 and CREE terms are discussed in the Response to 

comments document page 5-460. The GHG regulations refer to CO2 standards 

(although CREE emissions are measured and compared to the CO2 standards) 

because CO2 standards are easier for the general public to understand. In 

addition, the definition of carbon-related exhaust emissions (CREE) outlined in 

600.002-08 provides some clarification as follows: "For example, carbonrelated exhaust emissions (weighted 55 percent city and 45 percent highway) 

are used to demonstrate compliance with fleet average CO2 emission 

standards outlined in 86.1818(c) of this chapter." 

9.3 

Miscellaneous ­

Footprint 

Tolerances 

86.1803-01 and 600.002­

08 - Definition of 

Footprint 

When does EPA or NHTSA plan to publish acceptable or 

default tolerances for the footprint values? Is this 

something EPA can answer on its own or does this have 

to come from NHTSA? 

EPA is concerned about the design tolerances of footprint measurements and 

will work with NHTSA to address this issue in the future. NHTSA published a 

recommended laboratory test procedure to measure footprints, ref. TP-537-01, 

Mar 30, 2009 available at 

http://www.nhtsa.gov/DOT/NHTSA/Vehicle%20Safety/Test%20Procedures/Asso 

ciated%20Files/TP-537-01.pdf. EPA would consider it to be a violation of the 

terms of the certificate if a manufacturer's production footprint measurements 

were noteably different (e.g. resulting in smaller production footprints) than the 

footprint measurements submitted in the model year report. 

Page 8 
 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

9.4 

Miscellaneous ­

EPA Verify data 

base revisions for 

GHG 

requirements 

Is EPA implementing a fleet-average CREE calculation 

program into Verify? 

How would EPA inform manufacturers as to what inputs 

to the system will be required (i.e. meetings, workshop). 

Yes, EPA will be working with manufacturers throughout 2010, 2011 and 2012 

to implement GHG changes into EPA's Verify data base system. EPA has been 

working with the Verify contractor over the past year. A brief outline of planned 

Verify changes was provided at the September 23, 2010 EPA/Industry GHG 

workshop--see slide 83 of the presentation. EPA held the first webinar meeting 

on November 17, 2010. EPA deployed some GHG data base changes on May 

13, October 14 and December 16, 2011. The next deployment is scheduled for 

May or June of 2012. 

Additional information about upcoming Verify changes and upcoming meetings 

will be provided via the EPA list server. 

9.5 

Miscellaneous ­

Regulatory Text 

Correction/Typo 

86.1818-12(d) 

600.113-12(g)(4) 

1. 86.1818-12(d) In-use CO2 

exhaust emission standards., there 

is an incorrect reference to 

“600.113-08(g)(4)”, should be 

“600.113-12(g)(4)”. 

2. In 600.113-12(g)(4), there is an 

incorrect reference to “600.113(a) 

and (b)”, 600.113(a) and (b) deal 

with calculating FTP and HWFE 

fuel economy not CREE. 

EPA typos, as noted in the Reference column. 

1. EPA revised the regulations in the 2013 FE Labeling final rule (76 FR 39478, 

July 6, 2011), revising the incorrect reference from 600.113-08(g)(4) to 600.113­

12(g)(4). 

2. EPA agrees with the comment regarding the provisions of 600.113-12(g)(4) 

which incorrectly reference 600.113-12(a) and(b). EPA revised the regulations 

in the 2013 FE Labeling final rule (76 FR 39478, July 6, 2011), revising the 

incorrect reference from 600.113-12(a) and (b) to 600.113-12(h) through (n). 

9.6 

Miscellaneous ­

Regulatory Text 

Correction/Typo 

86.135-12(d) 

Previously, the provisions of 86.135­

00(d) read as follows: 

Practice runs over the prescribed 

driving schedule may be performed 

at test point, provided an emission 

sample is not taken, for the purpose 

of finding the appropriate throttle 

action to maintain the proper speedtime relationship, or to permit 

sampling system adjustment. Both 

smoothing of speed variations and 

excessive accelerator pedal 

perturbations are to be avoided. 

When using two-roll dynamometers 

a truer speed-time trace may be 

obtained by minimizing the rocking of 

the vehicle in the rolls; the rocking of 

the vehicle changes the tire rolling 

radius on each roll. This rocking may 

be minimized by restraining the 

vehicle horizontally (or nearly so) by 

using a cable and winch. 

The description in 40CFR 

86.135(d) of the GHG final rule 

reverts to the description from the 

1990 MY version. We believe this 

was an oversight. Details of text 

below: 

Current 86.135-12(d) reads as 

follows: 

Practice runs over the prescribed 

driving schedule may be 

performed at test point, provided 

an emission sample is not taken, 

for the purpose of finding the 

minimum throttle action to maintain 

the proper speed-time relationship, 

or to permit sampling system 

adjustment. Note: When using tworoll dynamometers a truer speedtime trace may be obtained by 

minimizing the rocking of the 

vehicle in the rolls; the rocking of 

the vehicle changes the tire rolling 

radius on each roll. This rocking 

may be minimized by restraining 

the vehicle horizontally (or nearly 

so) by using a cable and winch. 

Request that EPA amend the regulatory text to reflect the 

previous/correct language contained in 86.135-00(d). 

EPA agrees with the comment and will revise the regulations at the next 

opportunity. 

10. Penalties 

10.1 Penalties 

preamble to the final rule 

section III.E.4 and 6 

(pages 75 FR 25473-77 

and 25482 

In case model type CREE emissions go over the in-use 

standard level, re-calculation of the fleet average or/and a 

recall is possible, correct? 

If CO2 improvement measures are available/feasible, 

certain models can be recalled and appropriate fixes will 

be applied...what if there is no fix/remedy available? 

Please read the preamble to the final rule section III.E.4 and 6 (pages 75 FR 

25473-77 and 25482). Also, those subjects are addressed in the EPA 

Response to comments document pages 5-359 to 5-362 and on slide 67 of the 

presentation given at the Sept 23, 2010 EPA/Industry greenhouse workshop. 

EPA typically doesn't place any up-front restrictions on EPA enforcement 

actions---because each enforcement action has special needs, conditions, etc, 

and is handled on a case-by-case basis. 

Page 9 
 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

11. Reporting and Recordkeeping Requirements 

11.1 

Reporting and 

Recordkeeping 

Requirements ­

Reporting 

Requirements 

for Exempt 

86.1801(j) and (k) Final GHG rule. Reporting requirements. 

Are Pre-MY and final MY reports required for small volume 

manufacturer with an exemption? 

Can this be handled as part of Certification Preview or is a 

VERIFY module roll out planned? 

Exemptions from greenhouse gas requirements are discussed in the preamble of the 

final rule, pages 75 FR 25419-21, 75 FR 25424, and 75 FR 25483. Manufacturers 

qualifying for a Small Business Administration (SBA) exemption under 86.1801-12(j) are 

"exempt from the greenhouse gas emission standards specified in 86.1818-12 and in 

associated provisions in this part and in part 600 of this chapter;" ref. 86.1801-12(j). 

Thus, manufacturers qualifying for a SBA exemption are not required to submit premodel year report or a GHG model year report to EPA (but may be required to submit a 

CAFE model year report to EPA). For SBA exemptions, manufacturers are not required 

to submit a declaration to EPA outlining how they qualify for the exemption, but are 

required to provide in the Part 1 application "the applicable intermediate and full useful 

life emission standards to which the test group is to be certified;" ref. 40 CFR 86.1844­

01(d)(7). Note that current EPA regulations do not provide SBA-exempt manufacturers 

with the option to certify to GHG standards (or to earn GHG credits). However, in the 

light-duty 2017 and later GHG/CAFE proposed rule, EPA proposed that beginning with 

model year 2014, SBA-exempt manufacturers may optionally meet applicable GHG 

standards and thus, may earn CO2 credits under the primary GHG program); ref. 76 FR 

74994, Dec 1, 2011. Manufacturers 

Manufacturers qualifying for a conditional exemption under 86.1801-12(k) "may request 

a conditional exemption from compliance with the emission standards described in 

86.1818-12, paragraphs (c) through (e) and associated provisions in this part and in part 

600 of this chapter." ref. 40 CFR 86.1801-12(k). Note that this exemption does not 

exempt manufacturers from meeting N2O and CH4 emission standards. As outlined in 

paragraph 86.1801(k)(3), manufacturers requesting a conditional exemption are 

required to submit a declaration to EPA at least 30 days prior to the introduction of 

vehicles into commerce. If EPA subsequently approves the mfr's request for exemption, 

the mfr is not required to submit a pre-model year report or a GHG model year report to 

EPA (but will likely be required to submit a CAFE report to EPA). 

TLAAS requirements are discussed in the preamble to the final rule, pages 75 

FR 25414-19. Manufacturers using TLAAS provisions are not required to 

submit a TLAAS declaration to EPA, however they should outline in the premodel year report the details of how they qualify for TLAAS program, including 

11.2 

Reporting and 

Recordkeeping 

Requirements ­

TLAAS 

Reporting 

Requirements 

86.1818-12(e); 

86.1865-12(k)(7)(iii); 

86.1865-12(l); 

600.512-12; 

600.514-12 

What does EPA require in the TLAAS application (other 

than documentation that the manufacturer's does not 

comply with GHG standards without using the TLAAS 

program)? 

how they comply with the provisions of 86.1818-12(e)(3) and 86.1865­

12(k)(7)(iii). There is no specific "TLAAS application," however, TLAAS-related 

information should be included in the application for for certification, the premodel year report and the final model year report. The final model year report 

should provide the TLAAS standards, compliance level, qualifications, credit 

use, etc, ref. 86.1865-12(l)(2) and 600.512-12. 

In addition, EPA intends to incorporate TLAAS greenhouse gas data reporting 

requirements into the GHG/CAFE module of EPA's Verify data base system. 

We will schedule several meetings and testing sessions with manufacturers 

prior to and during the initial start-up of the new Verify GHG/CAFE module. 

Page 10 
 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

11.3 

Reporting and 

Recordkeeping 

Requirements ­

Maintenance of 

Records 

86.1865-12 (l), (1), (ii) 

§ 86.1865–12 (l) Maintenance of 

records and submittal of information 

relevant to compliance with fleet 

average CO2 standards 

(1)(ii) Manufacturers producing any 

passenger cars or light trucks 

subject to the provisions in this 

subpart must establish, maintain and 

retain all the following information in 

adequately organized records for 

each passenger car or light truck 

subject to this subpart: 

(A) Model year. 

(B) Applicable fleet average CO2 

standard. 

(C) EPA test group. 

Which specific vehicles do we need to maintain records 

for under § 86.1865–12 (l)(1)(ii)? Is this required for all 

vehicles produced beginning in MY 2012 or only for IUVP 

tested vehicles? We believe this requirement will be very 

difficult and burdensome to maintain for all vehicles and 

we believe it should only be required for IUVP vehicles. 

Many other manufacturers may have the same concern in 

maintaining records for all vehicles. Please clarify if this 

These requirements are intended for all production vehicles. As outlined in the 

provisions of 86.1865(l)(iii), "Records may be stored in any format and on any 

media, as long as manufacturers can promptly send EPA organized written 

records in English if requested by the Administrator." These requirements are 

very similar to current recordkeeping requirements outlined in 86.1862-04(a). 

(D) Assembly plant. 

(E) Vehicle identification number. 

(F) Carbon-related exhaust emission 

standard to which the passenger car 

or light truck is certified. 

(G) In-use carbon-related exhaust 

emission standard. 

(H) Information on the point of first 

sale, including the purchaser, city, 

and state. 

requirement is only for IUVP vehicles and when this 

requirement takes effect. 

11.4 

Reporting and 

Recordkeeping 

Requirements ­

Reporting 

Requirements

 §86.1865 (l) 

According to §86.1865 (l), reporting of MYs 2009-2011 

must be done the first time with the MY 2012 report, e.g. 

by 05/01/2013. 

According to §86.1867(e), reporting of MYs 2009-2011 

must be done at latest 90 days after the end of the 2011 

model year. 

According to §600.512 (a), the MY report must be 

submitted at latest 90 days after the end of the model 

year. 

Does §86.1865 (l) contain an error? 

No. There is not an error, but there are two separate things going on. 86.1865 

deals with the annual model year report, which are requirements that don't start 

until the close of the 2012 model year. 86.1865-12(l) is simply saying that when 

you submit your annual report for the first model year of the program (2012), 

you need to include certain elements relating to your early credits (if any). But 

86.1867 requires a single summary report for all early credits that includes data 

from all model years 2009-2011. Note that the content from the 2009-2011 

early model year report (which is due in early 2012) will be included in the final 

2012 model year report - due in early 2013. 

12. Testing 

12.1 

Testing ­

Analytically 

Derived 

CO2/CREE 

86.1835-01(b)(1)(vi) 

When the following condition is met, 

manufacturers have to conduct mfr 

confirmatory test: 

"The exhaust carbon-related exhaust 

emissions of the test as measured in 

accordance with the procedures in 40 

CFR Part 600 are lower than expected 

based on procedures approved by the 

Administrator." 

Do we have to obtain EPA approval for each model's 

analytically derived CREE estimation procedure? By when? 

The use of analytically derived CREE data is discussed in the preamble to the final rule, 

page 75 FR 25470. EPA will clarify in a future guidance letter the policy for 1) the use of 

analytically derived CREE and fuel economy data and 2) CREE cut points policy, ref. 

CISD-09-18 and CCD-04-06. Preliminary thoughts for the cut points guidance letter are 

that additional CREE cutpoints will not be needed (and the fuel economy cutpoints 

outlined in CISD-09-18 will be used for both fuel economy and CREE retesting). 

12.2 

Testing ­

Manufacturer 

Confirmatory 

Testing 

86.1835-01(b)(3) 

The manufacturer shall conduct a retest 

of the FTP or highway test if the 

difference between the fuel economy of 

the confirmatory test and the original 

manufacturer's test equals or exceeds 

three percent." 

If the fuel economy difference between both tests are within 

three percent, how should we calculate official CREE? 

For official CREE data, mfrs should use the same data as determined to be the official 

data for FE testing. In this case, EPA policy is outlined in the flow chart in EPA 

guidance letter VPCD-99-06 (page 14)---and the mfr's confirmatory test would be the 

"official" test for FE and CREE. 

Page 11 
 

 

 

 

 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

12.3 

Testing ­

Upstream 

Emission 

Calculations 

600.111-08(f) 

600.113-12(m) 

When calculating upstream emissions 

for ATV credits, there is no clear 

calculation of EC(for EV), ECF, 

CREE_CDED, CREE_CDGAS, 

CREE_CS(for PHV), CREE_up(for 

FCV) in S600.111-08(f). 

When calculating PHEV upstream 

emissions (=CREEcd+CREEcs), the 

UF(Utiliy Factor) is not applied. 

Will EPA clarify these regulations in the future? 

Will EPA decide/modify calculations in GHG label rulemaking 

this summer? 

CREE calculations for EVs, PHEVs, & fuel cell vehicles are outlined in the preamble to 

the final rule, pages 75 FR 25434-38. Upstream emission requirements for EVs, 

PHEVs, and fuel cell vehicles are outlined in the provisions of 40 CFR 600.113-12(m). 

For EVs and PHEVs, the provisions of 600.113-12(m)(1) and (m)(2) were revised in the 

2013 FE Labeling final rule (76 FR 39478, July 6, 2011). 

12.4 

Testing ­

Vehicles 

Equipped with 

Daytime 

Running Lights 

(DRLs) 

EPA guidance letter 

CD-94-02, February 9, 

1994 

Apparently the issue of daytime 

running lights came up in the GHG 

rule. The current procedure is to 

allow DRLs to be disconnected 

during the test. As I recall EPA didn't 

incorporate any change in the final 

GHG rule but said it would consider 

this an make changes if appropriate 

in the future. 

Background: EPA implemented 

the policy of not using daytime 

running lights (DRL) on the test 

based upon NHTSA's decision to 

ignore CAFE effect of DRL, thus 

providing an incentive to 

encourage DRLs for safety 

reasons. 

So has EPA considered this and is any change in the 

works? What is the earliet model year that might be 

affected if you make a change? 

Daytime running lights are not discussed in the final GHG rule, nor did EPA 

receive any comments related to EPA's daytime running light policy. At this 

time, EPA has no plans to revise the testing policy for vehicles equipped with 

daytime running lights outlined in EPA guidance letter CD-94-02, February 9, 

1994. If EPA decides to revise that policy, EPA will provide adequate lead time 

to affected manufacturers. 

12.5 Testing - N2O 

Measurement 

86.111-94; 

86.1065.275 

The complexity of N20 testing 

requirements raise significant 

concerns, for example: 

(i) Facilities – require significant 

upgrades specific to analyzers and 

software, and 

(ii) Lab Efficiency – collection of DF 

and cert data will constrain lab 

throughput due to potential void 

and maintenance issues. 

Will EPA accept extended use of N2O compliance 

statement beyond 2014 MY? 

N2O and N2O analyzer requirements are discussed in the preamble of the final 

rule (pages 75 FR 25421-24) and in the preamble to the light-duty 2017 and 

later GHG/CAFE proposed rule; ref. 76 FR 74993-94, Dec 1, 2011. 

In the 2017 and later light-duty GHG/CAFE proposed rule, EPA proposed to 

extend the use of an N2O compliance statement for two additional years 

(through model year 2016). Thus, as proposed, manufacturers will be required 

to measure N2O emissions beginning with the 2017 model year in order to 

demonstrate compliance with the N2O emission standard. 

13. Warranty 

13.1 

Warranty - A/C 

Credit 

Components 

Sections 207(a) and 207(i) 

of the CAA 

Does EPA require the inclusion of A/C system into warranty 

parts list of 2yr/2.4k, which was proposed in the preamble of 

NPRM? 

EPA warranty requirements for light-duty vehicles and trucks are discussed in the 

preamble of the final rule, pages 75 FR 25486-87. EPA warranty requirements for 

MDPVs are outlined in the provisions of 40 CFR 86.004-2. The defect warranty is 

required to cover emission-related components necessary to meet CO2 (CREE), CH4, 

N2O emission standards and emission-related components used to obtain optional 

GHG credits (including credits for reduction of air-conditioning refrigerant leakage 

and/or improving air conditioning system efficiency). The duration of the defect 

warranty depends on the applicable class of vehicles (e.g. for 2-year/24,000 miles for 

light-duty vehicles/trucks or 5 years/50,000 miles for MDPVs). 

13.2 

Warranty - A/C 

Credit 

Components 

Sections 207(a) and 207(i) 

of the CAA 

There was no modification in the 

section of warranty parts list, on the 

other hand, EPA requires the A/C 

warranty of 2yr/24k in the preamble. 

Will EPA modify the warranty parts lists? 

If so, will EPA add only the A/C system to 2yr/24k parts lists? 

Will EPA add other systems? Will EPA add any new systems to 

the 8yr/80,000 mile warranty requirements? 

A/C warranty requirements are manufacturer and model year specific (depending on the 

A/C systems which generate A/C leakage and efficiency credits). Therefore, EPA has 

no plans to modify the warranty parts list provided on the web at 

http://www.epa.gov/otaq/consumer/warr95fs.txt. Also, please see the EPA answer to 

question 13.1, above. 

13.3 

Warranty - A/C 

Credit 

Components 

Sections 207(a) and 207(i) 

of the CAA 

From 2012MY, AC systems 

generating GHG credit must 

provide 2yr./24K mile defect 

warranty.

 Does this mean mfrs. must offer 15yrs/150K mile 

warranty to such AC systems for PZEVs in California? 

Does this mean mfrs. have to offer 7 years/70K mile 

warranty to applicable AC systems if it is high-priced 

warranted parts in California? 

For Federal A/C warranty requirements, please see the EPA answer to question 13.1, 

above. For California warranty requirements, please consult with CARB. 

Page 12 
 

 

DRAFT Light-duty Greenhouse Gas - Manufacturer Questions and EPA Answers - January 2012

Issue 

No. Subject Regulation Reference Regulation Issue Manufacturer Questions EPA Answers 

Purpose and Scope of this Guidance Document 

 This document was prepared by EPA's Office of Transportation and Air Quality (OTAQ). It contains a record of EPA positions with respect to implementation of EPA requirements in the light-duty greenhouse gas rule (75 FR 25324, May 7, 2010 and any 

subsequent revisions to that rule which became effective on or before December 12, 2011). This document contains a record of the answers to the technical questions which EPA received from the light-duty automobile industry before and after EPA's September 23, 

2010 light-duty greenhouse gas workshop. Regulated parties may use this document to aid in achieving compliance with the regulations for light-duty vehicles (40 CFR Parts 85, 86 and 600).

 This document does not in any way alter the requirements in EPA regulations. Although the answers provided in this document interpret the regulations and indicate general plans for implementation of the regulations at this time, some of the responses may 

change as additional information becomes available, or as the agency further considers certain issues. The questions and answers contained in this document do not establish or change the legal rights or obligations of manufacturers in complying with EPA 

regulations. Further, this document does not establish binding rules or requirements and is not fully determinative of the issues addressed. Moreover, EPA decisions in any particular case will be made applying the law and regulations on the basis of specific facts. 

13.4 

Warranty 

Requirements for 

GHG AECDs 

86.1803-01 

Devices listed as auxilliary 

emission control devices (AECDs) 

in part I application require listing 

of part numbers of emission 

related components and these 

AECDs in part II and also them to 

be covered by the defect warranty. 

Can EPA comment on whether or not manufacturers 

must offer defect warranties on GHG AECDs, even 

though certification application requirements have not 

been changed in the GHG rule making? 

Please see EPA answers to questions 1.1 and 13.1 above, for information 

about listing part numbers in the Part 2 application and for information about the 

defect warranty requirements for GHG AECDs. Warranty requirements for lightduty vehicles and trucks are discussed in the preamble of the final rule, pages 

75 FR 25486-87. The defect warranty and EPA defect reporting requirements 

apply to AECDs and emission-related components necessary to meet CO2 

(CREE), CH4, N2O emission standards and to AECDs and emission-related 

components used to obtain optional CO2 (CREE) credits. 

Page 13