# Improvements for Heavy-Duty Engine and Vehicle Test Procedures, and Other Technical Amendments > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2020-05963 ## Record - **Collection:** Federal Register - **Document type:** Proposed Rule - **Published:** May 12, 2020 - **Citation:** 85 FR 28140 ## Text ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 9, 59, 60, 85, 86, 88, 89, 90, 91, 92, 94, 1027, 1033, 1036, 1037, 1039, 1042, 1043, 1045, 1048, 1051, 1054, 1060, 1065, 1066, and 1068 [EPA-HQ-OAR-2019-0307; FRL-10006-90-OAR] RIN 2060-AU62 Improvements for Heavy-Duty Engine and Vehicle Test Procedures, and Other Technical Amendments AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: The Environmental Protection Agency (EPA) is proposing changes to the test procedures for heavy-duty engines and vehicles to improve accuracy and reduce testing burden. EPA is also proposing other regulatory amendments concerning light-duty vehicles, heavy-duty vehicles, highway motorcycles, locomotives, marine engines, other nonroad engines and vehicles, stationary engines. These would affect the certification procedures for exhaust emission standards, and related requirements. EPA is proposing similar amendments for evaporative emission standards for nonroad equipment and portable fuel containers. These amendments would increase compliance flexibility, harmonize with other requirements, add clarity, correct errors, and streamline the regulations. Given the nature of the proposed changes, they would have neither significant environmental impacts nor significant economic impacts for any sector. DATES: Comments: Comments must be received on or before June 26, 2020. Public Hearing: If anyone contacts us requesting a public hearing on or before May 19, 2020, we will hold a hearing in Ann Arbor, Michigan at 10 a.m. on May 27, 2020. ADDRESSES: Comments. Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2019-0307, at http://www.regulations.gov . Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets . Public hearing. Individuals are invited to notify EPA of interest in a public hearing; see FOR FURTHER INFORMATION CONTACT . Public Participation: Public hearing. If we hold a public hearing, we will announce detailed information about the hearing on our website. Send requests for a hearing and questions about the status of a hearing to the contact identified in FOR FURTHER INFORMATION CONTACT . Comments. Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2019-0307, at http://www.regulations.gov . Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov . The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets . Docket. EPA has established a docket for this action under Docket ID No. EPA-HQ-OAR-2019-0307. All documents in the docket are listed on the www.regulations.gov website. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically in www.regulations.gov or in hard copy at Air and Radiation Docket and Information Center, EPA Docket Center, EPA/DC, EPA WJC West Building, 1301 Constitution Ave. NW, Room 3334, Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air Docket is (202) 566-1742. FOR FURTHER INFORMATION CONTACT: Alan Stout, Office of Transportation and Air Quality, Assessment and Standards Division, Environmental Protection Agency, 2000 Traverwood Drive, Ann Arbor, MI 48105; telephone number: (734) 214-4805; email address: stout.alan@epa.gov . SUPPLEMENTARY INFORMATION: Table of Contents I. General Information II. Heavy-Duty Highway Amendments A. Test Procedures and Compliance Model Changes B. Heavy-Duty Engine GHG Emission Standards and Flexibility C. Heavy-Duty Vehicle GHG Emission Standards and Flexibility D. Requests for Comment on Phase 2 Regulations E. Other Heavy-Duty Highway Amendments III. Other Amendments A. Ethanol-Blend Test Fuels for Nonroad Spark-Ignition Engines and Vehicles, Highway Motorcycles, and Portable Fuel Containers B. Removing Obsolete CFR Content C. Certification Fees (40 CFR part 1027) D. Additional Amendments for Motor Vehicles and Motor Vehicle Engines (40 CFR parts 85 and 86) E. Additional Amendments for Locomotives (40 CFR part 1033) F. Additional Amendments for Land-Based Nonroad Diesel Engines (40 CFR part 1039) G. Additional Amendments for Marine Diesel Engines (40 CFR parts 1042 and 1043) H. Portable Fuel Containers (40 CFR part 59) I. Evaporative Emission Standards for Nonroad Spark-Ignition Engines and Equipment (40 CFR part 1060) J. Additional Amendments for Nonroad Spark-Ignition Engines at or Below 19 kW (40 CFR part 1054) K. Amendments for General Compliance Provisions (40 CFR part 1068) L. Other Requests for Comment IV. Statutory Authority and Executive Order Reviews General Information A. Does this action apply to me? This action relates to companies that manufacture or sell new gasoline fueled light-duty vehicles, light-duty trucks, medium-duty passenger vehicles, or heavy-duty vehicles up to 14,000 pounds GVWR, as defined under EPA's CAA regulations, 1 and passenger automobiles (passenger cars), non-passenger automobiles (light trucks), and heavy-duty pickup trucks and vans as defined under National Highway Traffic Safety Administration's (NHTSA's) Corporate Average Fuel Economy (CAFE) regulations. 2 Additional amendments apply for different manufacturers of various types of nonroad and stationary engines, vehicles, and equipment. 1 “Light-duty vehicle,” “light-duty truck,” “medium-duty passenger vehicle,” and “heavy-duty vehicle” are defined in 40 CFR 86.1803-01. 2 “Passenger automobile” and “non-passenger automobile” are defined in 49 CFR 523.4 and 523.5, respectively. “Heavy-duty pickup trucks and vans” are defined in 49 CFR 523.7. Regulated categories and entities include the following: Category NAICS codes A Examples of potentially regulated entities Industry 333618, 336111, 336112, 336120, 336211, 336212, 336611, 336911, 336999 Motor vehicle manufacturers and engine manufacturers. Industry 811111, 811112, 811198, 423110 Commercial importers of vehicles and vehicle components. Industry 335312, 811198 Alternative fuel vehicle converters. Industry 326199, 332431 Portable fuel container manufacturers. A North American Industry Classification System (NAICS). This list is not intended to be exhaustive, but rather provides a guide for readers regarding entities likely to be regulated by this action. If you have questions regarding the applicability of this action to a particular entity, consult the person listed in the FOR FURTHER INFORMATION CONTACT section. B. What action is the Agency taking? This action proposes to amend the regulations that implement our air pollutant emission standards for engines, vehicles and mobile equipment. The proposed amendments, which are generally technical amendments that include corrections, clarifications, and flexibilities. In other words, this proposal comprises a significant variety of small changes for multiple types of engines and equipment. The majority of amendments being proposed would modify existing test procedures for heavy-duty highway engines and vehicles. These test procedure changes would improve accuracy, and in some cases, reduce test burden. They would apply for measurement of criteria pollutants (such as NO X ), as well as greenhouse gas pollutants (primarily CO 2 ). Other heavy-duty highway amendments would update EPA regulations to enhance implementation of existing emission standards. For example, some changes would reduce the likelihood that manufacturers would need to duplicate certification efforts to comply with EPA, Canadian, and Californian standards. Some amendments would make it easier for manufacturers to more fully account for the emission benefits of advanced emission control technology, which could provide them the opportunity to generate additional emission credits. These heavy-duty highway amendments are described in Section II. This notice also proposes other amendments that are generally administrative or technical in nature and include amendments for nonroad engines and vehicles. These amendments are described in Section III. Perhaps the most visible administrative amendment would be the elimination of hundreds of pages of obsolete regulations, which is described in Section III.B. C. What are the incremental costs and benefits of this action? This action is limited in scope and is not intended to include amendments that would have significant economic or environmental impacts. EPA has not drafted a Regulatory Impact Analysis. Heavy-Duty Highway Amendments A. Test Procedures and Compliance Model Changes Since the promulgation of the Phase 2 regulations, manufacturers have been revising their internal test procedures to ensure they will be able to comply with the new requirements that begin in model year 2021. In doing so, they have identified several areas in which the test procedure regulations could be improved (in terms of overall accuracy, repeatability and clarity) without changing the effective stringency of the standards. Commenters who believe that EPA has included changes that change the stringency of the standards are encouraged to consider the potential impact in the context of the full range of proposed changes to the test procedures, and to suggest ways in which EPA could avoid the impact of such changes on stringency. EPA is proposing numerous changes to the test procedure regulations to address manufacturers' concerns and to address other issues we have identified. These proposed changes are described below. The list includes numerous editorial changes that simply correct typographical/formatting errors or revise the text to improve clarity. Although these amendments are being proposed primarily in the context of heavy-duty engines and vehicles, the proposed amendments to part 1065 will also apply to nonroad engines, and the proposed amendments to part 1066 will also apply to light-duty vehicles. However, since these amendments are mostly editorial or adding flexibility, they will not adversely impact these other sectors. 1. 40 CFR Part 1036 Test Procedures The regulations in 40 CFR part 1036, subpart F, specify how to measure emissions from heavy-duty engines. The test procedure amendments being proposed for part 1036 are primarily for the purposes of adding flexibility and reducing variability in test results. Additional information that led to proposal of many of these changes arose from a test program at Southwest Research Institute (SwRI) that was jointly funded by EPA and the Engine Manufacturers Association (EMA). These amendments are summarized below, and readers are referred to the proposed part 1036, subpart F regulatory text for additional information. Amendments for other subparts of part 1036 ( i.e., amendments not directly related to test procedures) are discussed in Section I.C. • 1036.501(g)—Adding a new paragraph (g) to denote duty cycles for testing MY 2016-2020 engines. • 1036.501(h)—Adding a new paragraph (h)(2) to cross-reference citation of transient test cycle specification for testing MY 2021 and later engines. In paragraph (h)(3)(ii), adding clarification that weighting factors for the Ramped Modal Cycle (RMC) are to be applied to CO 2 to calculate the composite emission result. Note that this proposed rule includes amendments to refer to the steady-state duty cycle as the Ramped Modal Cycle rather than the Supplemental Emission Test. • 1036.503—Migrating 1036.510 to new 1036.503. Updating existing paragraph (c) and adding a new (c)(4) and (d)(4). The new text specifies that the engine manufacturer must provide idle speed and torque to the vehicle manufacturer. Additional direction given on handling data points for a low speed governor where the governor is active. • 1036.505—Adding a new paragraph (b) to give direction on both engine and powertrain testing. Modifying Table 1 to include vehicle speed and grade parameters to facilitate the hybrid powertrain testing option. • 1036.510—Adding a new section regarding transient testing of engines and hybrids to facilitate hybrid certification for both GHG and criteria pollutants. • 1036.525(d)(4)(ii)—Editorial revisions to equation and example calculations. • 1036.527—New section added to provide a means to determine hybrid powertrain systems rated power. This is needed to facilitate the addition of the hybrid powertrain testing option. • 1036.530(b)(1)(i) and (2)—Updating to require test fuel mass-specific energy content to be analyzed by three different labs and the arithmetic mean to be used in the calculation. Updating carbon mass fraction determination to allow analysis by a single lab only to facilitate on-line analysis from pipeline supplied natural gas. Updated to add ASTM method for determination of test fuel mass-specific energy content for natural gas. • 1036.530 Table 1—Updated footnote format in table. • 1036.535—Generally updating to improve the engine fuel mapping test procedures based on the jointly funded EPA-EMA test program. The overall result of these updates is to reduce the variability of the emission test results to improve lab-to-lab variability. • 1036.540—Generally updating to improve the cycle-average fuel mapping test procedure as a result of the jointly funded EPA-EMA test program at SwRI. The overall result of these updates is to reduce the variability of the emission test results to improve lab-to-lab variability. • 1036.543—Adding new section to address carbon balance error verification. This is a result of the jointly funded EPA-EMA test program. The overall result of these updates is to reduce the variability of the emission test results to improve lab-to-lab variability. 2. 40 CFR Part 1037 Test Procedures The regulations in 40 CFR part 1037, subpart F, specify how to measure emissions from heavy-duty vehicles. They also specify how to measure certain GEM inputs, such as aerodynamic drag, rolling resistance, and axle efficiency. The test procedure amendments being proposed for part 1037, which are summarized below, are primarily for the purpose of reducing variability in test results and adding optional test procedures. Given the technical nature of these proposed amendments, readers are referred to the regulatory text for additional details. Proposed amendments for other subparts of part 1037 ( i.e., amendments not directly related to test procedures) are discussed in Section I.C. • 1037.105 Table 1—Updated footnote format in table. • 1037.106 Table 1—Updated footnote format in table. • 1037.510(a)(2) and (e)—Edit in (a)(2) introductory paragraph. Updating (a)(2)(ii) and (iii) as result of the jointly funded EPA-Engine Manufacturers Association (EMA) test program at SwRI. The overall result of these updates is to reduce the variability of the emission test results to improve lab-to-lab variability. Update (e) making use of cruise control optional as variability can be high if cruise control is used. • 1037.510 Table 1—Updated footnote format in table. • 1037.515 Table 3—Updated footnote format in table. • 1037.520 Table 1 and (f)—Correcting typo in CdA value for low-roof cabs for Bin III. Updating cross-reference in (f). • 1037.520(g)—Adding some additional vehicle characteristics that need to be reported. Also providing clarification on the application of the 6x4D drive axle configuration. This includes a better description of the application as well as qualifiers that allow for use of this configuration. • 1037.520(i)—Adding torque converter characterization. • 1037.520 Table 1—Updating Table to include additional technologies and GEM input values for automatic engine shutdown systems. • 1037.520(j)(5)—Correcting error that transposed school and coach bus GEM inputs. • 1037.520 Table 6—Updated footnote format in table. • 1037.528(h)(6)(ii)—Adding direction to use good engineering judgment when measuring rolling resistance for equation 11. • 1037.528—Updating equation 14. The “+” is replaced with a “−”, correcting a typo. • 1037.534—Updating equation 6, and corresponding example problem. The update applies italics to “i”. • 1037.540—Updating equations 1, 2, and 3. The update applies italics to “i”. • 1037.540(e) and (f)—Adding section reference for location of standard payload. • 1037.540 Table 1—Updated footnote format in table. • 1037.550—Global updates as a result of the joint EPA-EMA fuel mapping test program at SwRI and general improvements based on experience gained from testing powertrain systems. The overall result of these updates is to reduce the variability of the emission test results to improve lab-to-lab variability. • 1037.551—Updating reference. • 1037.555—Updating equations 1 and 3, edits. The updates apply italics to “i”. • 1037.560—Making it optional to drain gear oil after break in. Providing the option of an alternative temperature range to provide harmonization with EC test procedure. Also, edits pertaining to improve the readability of the Ploss ( i.e., power loss) variable description. • 1037.565—Providing an option to map additional test points. Also, edits pertaining to improve the readability of the Ploss variable description. • 1037.570—Adding new section to determine torque converter capacity factor. This will allow a manufacturer to determine their own torque converter capacity factor instead of using the default value provided in GEM. The option to use the default value still remains. 3. 40 CFR Part 1065 Test Procedures The regulations in 40 CFR part 1065 specify general procedures for measuring emissions from engines—heavy-duty highway engines, as well as nonroad engines. The amendments being proposed for part 1065, which are summarized below, are primarily for the purpose of reducing variability in test results. The regulations in part 1065 rely heavily on acronyms and abbreviations (see 40 CFR 1065.1005 for a complete list). Acronyms used here are summarized in the following table: ASTM American Society for Testing and Materials CVS Constant-Volume Sampler DEF Diesel Exhaust Fluid ECM Electronic Control Module NIST National Institute for Standards and Technology NMC FID Nonmethane Cutter with a Flame Ionization Detector NMHC Nonmethane Hydrocarbon NMNEHC Nonmethane Nonethane Hydrocarbon RMC Ramped Modal Cycle THC FID Flame Ionization Detector for Total Hydrocarbons In addition to the amendments listed below that are being proposed for part 1065, we request comment on the use of ASTM test method D2784 to measure the sulfur content in liquefied petroleum gas test fuels. This method, which is specified as the applicable test method in § 1065.720, has been withdrawn by ASTM without replacement. We request comment on whether we should continue to specify this method or specify an active method. For example, should we specify ASTM D6667 instead and incorporate it by reference into the regulations? • 1065.1(g)—Updated test procedure URL. • 1065.130(e)—Revised language to denote that carbon balance should be performed to verify exhaust system integrity in place of chemical balance. • 1065.140(c)(6)(i)—Corrected typo. Replaced “dew point” with “dewpoint”. • 1065.140(e)(2)—Revised language to add clarification on how to determine minimum dilution ratio for discrete mode testing. • 1065.145(e)(3)(i)—Removed requirement to heat sample pump if it is located upstream of a NO X converter or chiller. Replaced with requirement to design the sample system to prevent aqueous condensation. Given that the concern is loss of NO 2 in the sampling system, the pump itself doesn't necessarily need to be heated as there are a number of ways to prevent condensation. • 1065.170—Revised to allow you to stop sampling during hybrid tests when the engine is off and allow exclusion of the sampling off portions of the test from the proportional sampling verification. Also added provision for hybrid testing to allow supplemental dilution air to be added to the bag in the event that sampled volumes are too low for emission analysis. • 1065.205 Table 1—Revised with edits and the addition of a recommended performance specification for fuel mass scales to reduced fuel flow measurement error. • 1065.220(a) introductory and (a)(3)—Updated the application of fuel flow meter to more correctly reflect how and what they are used for in 1065. • 1065.225(a) introductory and (a)(3)—Updated the application of intake flow meter to more correctly reflect how and what they are used for in 1065. • 1065.247(c)(2)—Edit to apply requirements to DEF dosing unit rather than to the engine. • 1065.260(e)—Add the word “some” as a qualifier for gaseous fueled engines with respect to using the additive method for NMHC determination. • 1065.266—Updated URL. • 1065.275—Deleted URL and replaced with reference to URL in 1065.266. • 1065.280(a)—Updated to reflect that there is no method in 1065.650 for determining oxygen balance and that you should develop a method using good engineering judgment. • 1065.303 Table 1—Updated for formatting. Updated to add Fuel mass scale and DEF mass scale to the linearity verifications in 1065.307. Updated verification in 1065.341 to replace “batch sampler” with “PFD” as PFD is the preferred language. Updated one, and added two, footnotes excluding linearity verification for DEF flow if the ECM is used and for fuel and intake air flow if propane checks or carbon balance is performed. This is not a new exemption, it just relocates it to the footnote area. • 1065.307(d)(4)—Revised to include DEF mass flow rate. The paragraph is also enhanced to include additional requirement to correct or account for buoyancy effects and flow disturbances to improve the flow measurement. • 1065.307(d)(6)(i)—Revised to state that the span gas can only contain one single constituent in balance air (or N 2 if using a gas analyzer) as the reference signal for linearity determination. • 1065.307(d)(7)—Revised to state that the span gas can only contain one single constituent in balance air (or N 2 if using a gas analyzer) as the reference signal for linearity determination. • 1065.307(d)(9)—Expanded paragraph to include fuel and DEF mass scales and provided additional requirements for performing the linearity verification on these scales. • 1065.370(e)(3)(i) and (ii)—Edits to make intent clear. • 1065.307(e)(3)(iii)—Defined m max for a fuel mass scale. • 1065.307(e)(5)—Provided additional information surrounding requirements for using a propane check or carbon balance verification in place of a flow meter linearity verification. • 1065.307(e)(7)(i)(F) and (G)—Added transmission oil and axle gear oil to temperature measurements that require linearity verification. • 1065.307 Table 1—Added DEF flow rate. • 1065.307 Table 2—Added a new Table 2 to provided additional guidance on when optional verifications to the flow meter linearity verifications can be used. • 1065.309(d)(2)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.315(a)(3)—Editorial revisions. • 1065.320(b) and (c)—Deleted the existing paragraph (b) and moved the existing (c) to (b) as this is now adequately covered in 1065.307. • 1065.341 introductory text—Revised to clarify which subparagraphs apply to CVS and which apply to PFD. • 1065.341(g)—Revised to replace “batch sampler” with “PFD” throughout. Also, edited to provide further clarification on the procedure. • 1065.341(h)—New paragraph added to reference Table 2 of 1065.307 regarding when alternate verifications can be used. • 1065.342(d)(2)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.350(d)(2)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.355(d)(2)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.360(a)(4)—Added new requirement to determine methane and ethane THC FID response factors as a function of exhaust molar water content when measuring emissions from a gaseous fueled engine. This is to account for the effect water has on non-methane cutters. • 1065.360(d)(12)—Added process to determine methane and ethane THC FID response factors as a function of exhaust molar water content when measuring emissions from a gaseous fueled engine. This is to account for the effect water has on non-methane cutters. • 1065.365(d)—Added new requirement to determine NMC FID methane penetration fraction and ethane response factor as a function of exhaust molar water content when measuring emissions from a gaseous fueled engine. This is to account for the effect water has on non-methane cutters. • 1065.365(d)(10) and (11)—Added process to determine NMC FID methane penetration fraction and ethane response factors as a function of exhaust molar water content when measuring emissions from a gaseous fueled engine. This is to account for the effect water has on non-methane cutters. • 1065.370(e)(5)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.375(d)(2)—Updated to allow the use of water vapor injection for humidification of gases. • 1065.410(d)—Updated to state that you may repair a test engine if the parts are unrelated to emissions without prior approval. If the part may affect emissions, prior approval is required. • 1065.510(a), (b)(5)(i), and (f)(4)(i)—Removed requirement for engine stabilization during mapping and relocated it to 1065.510(b)(5)(i), which lays out the mapping procedure. Added a recommended stabilization time at each setpoint. Also added allowance to specify CITT as a function of idle speed in cases where an engine has an adjustable warm idle or enhanced idle. • 1065.512(b)(1) and (2)—Added additional procedures on how to operate the engine and validate the duty-cycle when an engine utilized enhanced-idle speed. This also addresses denormalization of the reference torque when enhanced-idle speed is active. • 1065.530(a)(2)(iii)—Added new instruction on how to determine that the engine temperature has stabilized for air cooled engines. Part 1065 is deficient on how to determine this. • 1065.530(g)(5)—New paragraph to cover carbon balance error verification if it is performed as part of the test sequence. • 1065.543—New section on carbon balance error verification procedure. This was added to further reduce measurement variability for the fuel mapping test procedure in part 1036. • 1065.602(b), (c), (d), (e), (g), (h), (j), (k)—Editorial revisions. The updates apply italics to “i”. • 1065.602 Table 2—Corrected an Nref-1 typo for value “22”. It was mistakenly listed as “20”. • 1065.602(f)—Updated footnote format in table. • 1065.610(a)(1)(iv)—Editorial updates applying italics to “i”. • 1065.610(a)(2)—Clarification to denote that the alternate maximum test speed determined is for all duty-cycles. • 1065.610(d)(3)—Added provision to use good engineering judgment to come up with an alternate procedure for adjusting CITT as a function of speed. • 1065.640(a) and (d)(1)—Deleting a comma in (a)(1). Providing a conversion to kg/mol for Mmix in (d)(1). Also correcting an error in the example problem to equation 1065.640-10 where Mmix was used with the wrong units. • 1065.642(b)—Section reference correction. • 1065.642(c)(1)—Defining C f. • 1065.643—New section on carbon balance error verification calculations to support the new section 1065.543. • 1065.650(b)(3)—Added DEF to what is needed for chemical balance. • 1065.650(c)(1)—Relocated transformation time requirement here from 1065.650(c)(2)(i). • 1065.650(c)(3)—Equation edit. The update applies italics to “i”. • 1065.650(d)(7)—Editorial updates applying italics to “i”. • 1065.650(f)(2)—Added DEF to what is needed for chemical balance. • 1065.655 title—Added “DEF”. • 1065.655(c)(3)—Updated x ccombdry variable description to include injected fluid. • 1065.655(e)(1)(i)—Added additional clarity regarding determination of carbon and hydrogen mass fraction of fuel, specifically to S and N content. • 1065.655(e)(4)—Equation and variable edits for format. The updates apply italics to “i”. • 1065.655 Table 1—Updated reference. • 1065.655(f)(3)—Restricted the use of equation 1065.655-25 if the standard setting part requires carbon balance verification. Also, the section contains edits for format. • 1065.655(g)(1)—Updated reference. • 1065.659(c)(2) and (3)—Added DEF to chemical balance. • 1065.660(b)(4)—Variable edit. Corrected chemical formula typo for acetaldehyde. • 1065.660(c)(2)—Included NMC FID as allowable option in NMNEHC calculation. • 1065.665(a)—Deleted the variable and description for C # as it is not used in any calculation in this section. • 1065.667(d)—Added DEF to chemical balance description. • 1065.695(c)(8)(v)—Added carbon balance verification. • 1065.701(b)—Updated title for California gasoline type. • 1065.701 Table 1—Updated footnote format in table. • 1065.703 Table 1—Updated to correct units for kinematic viscosity and updated footnote format in table. • 1065.705 Table 1—Updated to correct units for kinematic viscosity and updated footnote format in table. • 1065.710 Table 1—Edits for format consistency and updated footnote format in table. • 1065.710 Table 2—Edits for format consistency. Added allowance to use ASTM D5769 for total aromatic content determination and ASTM D6550 for olefin determination. These were added because the dye used in the current method, ASTM D1319 is becoming scarce and thus an alternate method is needed. Updated footnote format in table. • 1065.715 Table 1—Updated footnote format in table. • 1065.720 Table 1—Updated footnote format in table. • 1065.750 Table 1—Updated footnote format in table. • 1065.905 Table 1—Updated footnote format in table. • 1065.915 Table 1—Updated footnote format in table. • 1065.1001—Updated definition of test interval to note that the mass of emissions is determined over it. • 1065.1005(a)—Updated footnote format in table. • 1065.1005(a), (c) and (d)—Updated to follow NIST SP-811 format. • 1065.1005(a) and (e)—symbols and subscripts updated to reflect new one added during the above revisions to part 1065. • 1065.1005(f)(2)—molar mass of ethane added. Updated footnote format in table. 4. 40 CFR Part 1066 Test Procedures The regulations in 40 CFR part 1066, specify general procedures for measuring emissions from vehicles. The amendments being proposed for part 1066, which are summarized below, are primarily editorial. • 1066.1(g)—Updated to current URL. • 1066.135(a)(1)—Widened the range for verifications of a gas divider derived analyzer calibration curve to 10 to 60%. This is to ease lab burden with respect to the number of gas cylinders they must have on hand. Also, made this midspan check optional as it is no longer needed because part 1066 requires yearly linearity verification of the gas divider. • 1066.210(d)(3)—Changed acceleration of Earth's gravity from calculation under 40 CFR 1065.630 to a default value of 9.80665 m/s 2 . This was changed because the track coastdown doesn't take place in the same location that the dynamometer resides. Therefore, best practice is to use a default value for gravity. • 1066.255(c)—Added clarification that the torque transducer zero and span are mathematically done prior to the start of the procedure. • 1066.270(c)(4)—Corrected units for force in mean force variable description. Corrected example problem solution. • 1066.275—Extended the frequency to an optional 7 days prior to testing if historic data from the test site supports a frequency of more than 1 day. • 1066.405—Updated title to include “maintenance”. • 1066.405(a)-(c)—Moved introductory paragraph to (a). Created new paragraphs (b) and (c) to address test vehicle inspection, maintenance and repair, consistent with 1065.410. • 1066.420 Table 1—Updated footnote format in table. • 1066.605—Edit in paragraph (c)(4), NMHC typo, corrected to NMHCE. Edits to equation 1066.605-10, italics added for format consistency. • 1066.610—Edit to equation 1066.610-4. Italics added for format consistency. • 1066.710(c)(1)(A)—Updated for clarity. • 1066.710(c)(2)—Updated to more clearly reflect how automatic HVAC control operates in vehicles and how it should be operated for the test. • 1066.801 Figure 1—Updated to reflect that the initial vehicle soak, as outlined in the regulations, is a 6-hour minimum and not a range of 6 to 36 hours. • 1066.930—Added a period to the end of the sentence. • 1066.1005(c) and (d)—Updated to follow NIST SP-811 format. • 1066.1005(f)—Updated footnote format in table. 5. Greenhouse Gas Emissions Model (GEM) GEM is a computer application that estimates the greenhouse gas (GHG) emissions and fuel efficiency performance of specific aspects of heavy-duty (HD) vehicles. Under the existing Phase 2 regulations, GEM 3.0 is used to determine compliance with the Phase 2 standards from several vehicle-specific inputs, such as engine fuel maps, aerodynamic drag coefficients, and vehicle weight rating. 3 GEM simulates engine operation over two cruise cycles, one transient cycle, and for vocational vehicles, idle operation. These results are weighted by GEM to provide a composite GEM score that is compared to the standard. 3 Greenhouse gas Emissions Model (GEM) Phase 2, Version 3.0, July 2016. A working version of this software is also available for download at http://www.epa.gov/otaq/climate/gem.htm . This version has been incorporated by reference at 40 CFR 1037.810. EPA is to incorporate by reference into the regulations a revised version of GEM (Version 3.5) for manufacturers to demonstrate compliance with the Phase 2 standards. 4 The following changes have been incorporated in the proposed new version, to allow additional compliance flexibilities and improve the vehicle simulation: 4 Greenhouse gas Emissions Model (GEM) Phase 2, Version 3.5, November 2019. A working version of this software is also available for download at http://www.epa.gov/otaq/climate/gem.htm . • Correcting how idle emission rates are used in the model. • Increasing the allowable weight reduction range to 25,000 pounds. • For powertrain input, adding an input for powertrain rated power to scale default engine power. • Recalibrated driver over speed allowance on cruise cycles from 3 mph to 2.5 mph. • Revised engine cycle generation outputs with corrected engine cycle generation torque output from model based on simulated inertia and rate limited speed target. • Added scaling of powertrain simulation default engine and transmission maps based on new rated power input. • Changed interpolation of fuel map used in post processing to be consistent with one used in simulation. • Powertrain accessory load correction. • Add torque converter k-factor input option. • Cycle average cycles: add flag for points that are to be considered “idle.” • Improved handling of large input tables. Of these, the changes for idling emissions are the most significant. GEM 3.0 included an error where parked idle fuel map was used for ARB transient idle correction, which has been corrected for GEM 3.5 to use the drive idle portion of the map. (Note also that parked fuel map is now only required for vocational vehicles.) GEM 3.5 reads idle speed from the vehicle file and allows manufacturers to use default values that EPA used to develop the standards. Other idle changes include additional adjustments to cycle average fuel for differences between mapped idle and simulated idle using non-moving average speed and load of the ARB transient cycle average map, regression lookup of cycle average map uses only portions with vehicle moving, and post-process adjustment to fuel consumption based on simulated idle speed/load. Preliminary evaluations of GEM 3.5 indicate that there is little difference between GEM 3.0 and GEM 3.5 for cruise cycle operation. However, it is possible some minor differences may be observed for transient and idle operation of some vocational vehicles. We request comment on whether these differences would impact impact the effective stringency of the standards and whether either GEM or the regulations need to be revised to address them. B. Heavy-Duty Engine GHG Emission Standards and Flexibility 1. Vocational Engines and Emission Credits We are proposing to revise how Phase 1 engine credits from vocational engines are treated in the Phase 2 program. As described below, we are proposing to allow more flexibility provided the credits are adjusted to accurately reflect the correct baseline. In developing the baseline emission rates for vocational engines in the final Phase 2 rulemaking, we considered MY 2016 FTP certification data for diesel engines, which showed an unexpected step-change improvement in engine fuel consumption and CO 2 emissions compared to data considered in the proposed rule. The proposed baseline emission rates came from the Phase 1 standards, which in turn were derived from our estimates of emission rates for 2010 engines. The underlying reasons for this shift in the final rule were mostly related to manufacturers optimizing their SCR thermal management strategy over the FTP in ways that we (mistakenly) thought they already had in MY 2010 ( i.e., the Phase 1 baseline). As background, the FTP includes a cold-start, a hot-start and significant time spent at engine idle. During these portions of the FTP, the NO X SCR system can cool down and lose NO X reducing efficiency. To maintain SCR temperature, manufacturers initially used a simplistic strategy of burning extra fuel to heat the exhaust system. However, during the development of Phase 1, EPA believed manufacturers were using more sophisticated and efficient strategies to maintain SCR temperature. EPA's misunderstanding of the baseline technology for Phase 1 provided engine manufacturers the opportunity to generate windfall credits against the FTP standards. For the Phase 2 FRM, EPA revised the baseline emission rate for vocational engines to reflect the actual certified emission levels. The Phase 2 vocational engine final CO 2 baseline emissions are shown in the table below. More detailed analyses on these Phase 2 baseline values of tractor and vocational vehicles can be found in Chapter 2.7.4 of the Phase 2 Final RIA. 5 5 Greenhouse Gas Emissions and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles—Phase 2. Regulatory Impact Analysis, August 2016, EPA-420-R-16-900. See p. 2-76. Phase 2 Vocational Engine CO 2 and Fuel Consumption Baseline Emissions Units HHD MHD LHD g/bhp-hr 525 558 576 gal/100 bhp-hr 5.1572 5.4813 5.6582 EPA did not allow the carryover of Phase 1 vocational engine credits into the Phase 2 program, consistent with these adjustments to the baselines. Since this issue does not apply for RMC emissions, the restriction was applied only for engines certified exclusively to the FTP standards (rather than both FTP and RMC standards). We believed that allowing engine credits generated against the Phase 1 diesel FTP standards to be carried over into the Phase 2 program would have inappropriately diluted the Phase 2 engine program. However, this was in the context of unadjusted credits. After further consideration, we now believe that it would not dilute the program if the credits were appropriately adjusted to more accurately reflect improvement over the true baseline levels. Allowing the portion of the credits that represent actual emission improvements to be carried forward would be consistent with our rationale from Phase 2. Thus, we are proposing in § 1036.701(j) that for Phase 1 vocational engines with emissions below the Phase 2 baseline engine values, manufacturers may recalculate and generate credits relative to the baseline levels. The recalculated vocational engine credits would be allowed into the Phase 2 engine program to the same extent as tractor engine credits. As noted in the Phase 2 FRM, allowing additional flexibility for compliance with engine standards does not cause any increase in emissions because the manufacturers must still comply with the vehicle standards. (See 81 FR 73499). However, this flexibility could allow some manufacturers to find a less expensive compliance path. We request comment on these proposed changes and any potential impact. 2. Confirmatory Testing of Engines and Measurement Variability During the Phase 2 rulemaking, manufacturers raised concern about measurement variability impacting the stringency of the engine GHG standards and fuel map requirements. As noted in the Phase 2 FRM, the final standards were developed to account for this. (81 FR 73571, October 25, 2016). Manufacturers raised particular concern about variability of fuel map measurements because neither they nor EPA had sufficient experience measuring fuel maps (in a regulatory context) to fully understand potential impacts. We estimated the fuel map uncertainty to be equivalent to the uncertainty associated with measuring CO 2 emission and fuel consumption over the FTP and RMC cycles, which we estimated to be about one percent. However, the Phase 2 FRM further noted that we would incorporate test procedure improvements that would futher reduce test result uncertainty. We also noted that: “If we determine in the future . . . that the +1.0 percent we factored into our stringency analysis was inappropriately low or high, we will promulgate technical amendments to the regulations to address any inappropriate impact this +1.0 percent had on the stringency of the engine and vehicle standards.” (81 FR 73571, October 25, 2016) In conjunction with this commitment, EPA agreed to work with engine manufacturers to better understand the variability of measuring fuel maps. Through that work, we identified several sources of variability that could be reduced by making small changes to the test procedures. EPA is proposing these changes, which are listed in Sections I.A.1 through I.A.3 of this NPRM. SwRI performed emission measurements in multiple test cells and identified distributions of error for other test inputs such measured fuel properties and calibration gas concentrations. SwRI then used a Monte Carlo simulation to estimate a distribution of errors in measured fuel maps. 6 After reviewing the results, EPA has three significant observations: 6 “Measurement Variability Assessment of the GHG Phase 2 Fuel Mapping Procedure”, Southwest Research Institute, Final Report, December 2019. 1. The variability of measuring CO 2 and fuel consumption during fuel mapping is greater than the one percent assumed in the Phase 2 FRM. 2. The variability of measuring CO 2 and fuel consumption during the fuel mapping procedure is roughly the same as that of the FTP and RMC cycles. 3. Measuring CO 2 and fuel consumption at idle is particularly challenging. Given these results, we understand why manufacturers would be concerned about the possibility of EPA changing an official fuel map results as a consequence of EPA confirmatory testing where the measured maps were within the expected range of variability. On the other hand, the similarity between the variability of measuring fuel maps and the variability of measuring CO 2 and fuel consumption over the FTP and RMC cycles (measurements for which EPA has already determined in both Phase 1 and Phase 2 that no such allowances are needed) suggests that manufacturers should ultimately be able to comply without any special provisions. We are also considering this issue in the context of our longstanding policy that emission measurements made at our National Vehicle and Fuel Emissions Laboratory are official emission results. (See for example, § 1036.235.) We are hesitant to change any long-standing policy in a technical amendment rulemaking. Nevertheless, while we believe this issue ultimately will need to be addressed in a broader context, we are proposing a transitional approach to address the issue of engine mapping variability, as discussed below. We are proposing an interim provision in 40 CFR 1036.150, under which EPA will not replace a manufacturer's fuel maps during confirmatory testing if the EPA-measured fuel maps were within 2.0 percent of the manufacturer's maps. We are proposing this as an interim provision but are not including an end date at this time. We would intend to reevaluate this provision as we learn more about the impact of measurement variability during fuel mapping, including the full impact of the proposed test procedure improvements that are intended to reduce measurement variability. Since, this 2.0 percent reflects real testing variability, EPA anticipates that manufacturers could not know how the variability would affect an individual test result, which would preclude them from relying upon this margin for compliance in current engine designs or in any potential engine redesign. Additionally, EPA emphasizes that we are proposing to adopt this as an interim provision, and thus manufacturers should not otherwise rely on this provision as a compliance strategy for engine design, as EPA intends to revisit it based on further data and developments. We are also proposing an algorithm for comparing fuel maps to one another. Because fuel maps are multi-point surfaces instead of single values, it would be a common occurrence that some of EPA's points would be higher than the manufacturer's while others would be lower. We propose that EPA's measured fuel maps would be used with GEM according to § 1036.540 to generate emission duty cycles which simulate several different vehicle configurations, generating emission results for each of the vehicles for each of the duty cycles. Each individual duty cycle result could be weighted using the appropriate vehicle category weighting factors in Table 1 of 40 CFR 1037.510 to determine a composite CO 2 emission value for that vehicle configuration. If the process is repeated for the manufacturer's fuel maps, the average percent difference between fuel maps could be calculated as: EP12MY20.000 Where: i = an indexing variable that represents one individual weighted duty cycle result for a vehicle configuration. N = total number of vehicle configurations. e CO2compEPA = total composite mass of CO 2 emissions in g/ton-mile for the EPA confirmatory test, rounded to the nearest whole number for vocational vehicles and to the first decimal place for tractors. e CO2compManu = total composite mass of CO 2 emissions in g/ton-mile for the manufacturer test, rounded to the nearest whole number for vocational vehicles and to the first decimal place for tractors. We request comment on the interim approach, and whether it appropriately balances the impacts of testing variability for fuel maps. 3. Other Minor Heavy-Duty Engine Amendments EPA is proposing three additional amendments to part 1036: • Correcting the assigned N 2 O deterioration factor in § 1036.150(g). In the Phase 2 NPRM, EPA proposed to lower the N 2 O standard from 0.10 g/hp-hr to 0.05 g/hp-hr for model year 2021 and later diesel engines. In that context, we also proposed to lower the assigned deterioration factor (DF) from 0.020 g/hp-hr to 0.010 g/hp-hr for model year 2021 and later diesel engines. EPA explained in the preamble that we were not finalizing the change to the standard (81 FR 73530), but inadvertently finalized the proposed DF change in the regulations. Today, EPA is proposing to correct the DF back to 0.020 g/hp-hr for all diesel engines, consistent with the continuation of the 0.10 g/hp-hr N 2 O standard. • Clarifying a reference to non-gasoline engine families in § 1036.705(b)(5). The second sentence of § 1036.705(b)(5) is intended to refer to non-gasoline engine families. However, the existing text is not clear. As written, it can be read to mean that gasoline engine families may not generate emission credits. EPA is proposing to add “non-gasoline” to make the intended meaning clearer. • Engine families. Proposing to allow engine families to be divided into subfamilies with respect to CO 2. This allowance would simplify the certification process without changing the overall requirements. • Adding a summary of previously applicable emission standards as Appendix I of part 1036. The proposed new Appendix is needed for reference to previously applicable emission standards and will cover regulatory text being deleted from 40 CFR part 86. C. Heavy-Duty Vehicle GHG Emission Standards and Flexibility 1. Considerations of Aerodynamic Compliance Data The aerodynamic drag of a vehicle is determined by the vehicle's coefficient of drag (C d ), frontal area, air density and speed. The regulations in § 1037.525 allow manufacturers to use a range of techniques, including wind tunnel testing, computational fluid dynamics, and constant speed tests. This broad approach is appropriate given that no single test procedure is superior in all aspects to other approaches. However, we also recognized the need for consistency and a level playing field in evaluating aerodynamic performance. To address the consistency and level playing field concerns, EPA adopted an approach that identified coastdown testing as the reference aerodynamic test method, and specified a procedure to align results from other aerodynamic test procedures with the reference method by applying a correction factor (F alt-aero ) to results from alternative methods (§ 1037.525(b)). With this approach, it is important that F alt-aero be accurate. Thus, the regulations (§ 1037.525(b)) require that manufacturers use good engineering judgement 7 when developing F alt-aero , which would include considering all applicable coastdown data that are available. The applicable test data would be those coastdown results that were collected according to the specified test procedures, whether collected by the manufacturer during certification and SEAs, or by EPA during confirmatory testing. 7 Good engineering judgment means judgments made consistent with generally accepted scientific and engineering principles and all available relevant information. See 40 CFR 1068.5 for additional discussion about applying good engineering judgment. Consider the hypothetical example shown in the figure below, where a manufacturer has coastdown results for eight vehicles. The plot shows the coastdown results corrected to represent wind averaged C d A, plotted against the corresponding wind average wind tunnel results. Applying good engineering judgement to such a dataset would lead a manufacturer to separate the vehicles into two groups, with each having its own F alt-aero value. The manufacturer would then need to work with EPA to determine how to appropriately apply these F alt-aero values to other vehicle configurations. As described in 40 CFR 1037.235, EPA may perform confirmatory testing on the manufacturer's vehicles, including a vehicle tested to establish the F alt-aero value. The regulations also include an interim provision in § 1037.150(s) that states: If we conduct coastdown testing to verify your F alt-aero value for Phase 2 tractors, we will make our determination using a statistical analysis consistent with the principles of SEA testing in § 1037.305. We will calculate confidence intervals using the same equations and will not replace your test results with ours if your result falls within our confidence interval or is greater than our test result. We are proposing to revise the interim allowance in § 1037.150(s) to require EPA to perform a minimum of 100 valid runs before replacing a manufacturer's value. Test conditions for coastdown testing are another important consideration. For our testing, EPA intends to minimize the differences between our test conditions and those of the manufacturer by testing at similar times of the year. However, because of the limited number of coastdown test facilities and the challenges of scheduling time for testing, we cannot commit to testing during the same season as the manufacturer. In addition, even if we could test during the same season, we cannot prevent differences in test conditions. Some manufacturers have expressed concern that this approach leaves too much risk for them because changing an F alt-aero value would impact a large portion of their production and could undermine their compliance plans. These manufacturers suggest that EPA should revise the regulations to provide for larger differences before EPA is allowed to replace their value. Although we understand this concern, we do not believe the manufacturers' suggestion would be the appropriate long-term solution. When multiple measurements provide different values, good engineering judgment would generally call for more data rather than selecting a single value. Keeping with this principle, EPA is requesting comment on a potential allowance for manufacturers to conduct additional coastdown testing in response to a change by EPA to their F alt-aero value through a 40 CFR 1068.5 good engineering judgment request. EPA would attempt to be present to witness the testing, and potentially take our own measurements. EPA would follow the procedures under 40 CFR 1068.5 in responding to the manufacturer to determine an appropriate F alt-aero value, consistent with good engineering judgment. Section 208 of the Act provides EPA broad oversight authority for manufacturer testing. Consistent with that authority, we are proposing to add a provision to our regulations at 40 CFR 1037.525(b)(8) to encourage manufacturers to proactively coordinate with EPA to have compliance staff present when a manufacturer conducts its coastdown testing to establish F alt-aero values. Being present for the testing would give EPA greater confidence that the test was conducted properly, and thus, would make it less likely that EPA would need to conduct aerodynamic confirmatory testing on the vehicle. Additionally, under our current regulations, see 40 CFR 1037.301 and 1037.305, EPA may require, and generally intends to require for the 2021 model year, that manufacturers perform SEA testing of at least one of their reference configurations. We are also proposing to revise the minimum number of runs required for a manufacturer to fail an SEA. Under the current Phase 2 regulations, a manufacturer could fail an SEA after as few as 24 valid runs. However, review of more recently available indicates that false failures may occur if the decision is based on 24 runs. Therefore, we are proposing to require a minimum of 100 valid runs before a vehicle is deemed to have failed the SEA test. While we believe that these changes and clarifications would largely address the manufacturers' concerns, we request comment on other possible improvements to the aerodynamic test procedures and compliance program. 2. Idle Reduction for Tractors The Phase 1 version of GEM gives credit for idle emission reduction technologies that include a tamper-proof automatic engine shutoff system (AESS), with few override provisions. Phase 2 GEM gives credit for a wider variety of idle reduction strategies, recognizing technologies that are available on the market today, such as auxiliary power units (APUs), diesel fired heaters, and battery powered units. For example, a tamper-proof AESS with a diesel APU would be credited with a 4 percent reduction in emissions, while an adjustable AESS with a diesel fired heater would be credited with a 2 percent reduction in emissions (See 81 FR 73601, October 25, 2016). We now realize that the regulations should also recognize combinations of these technologies. It is common for sleeper-cab tractors to include a combination of these technologies to address a broader range of ambient temperatures. For example, a fuel operated heater may be used for heating during the winter months, while a battery APU may be used for air conditioning in the summer. Therefore, we are proposing to add the following combinations of idle reduction technologies to Table 9 of § 1037.520. By adding these values to GEM, it would reduce the compliance burden for manufacturers who would otherwise need to pursue off-cycle credits for these technology combinations. The values of the proposed technology benefits were determined using the same methodology used in the Phase 2 final rule. 8 9 8 U.S. Environmental Protection Agency. Greenhouse Gas Emissions and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles—Phase 2: Regulatory Impact Analysis. EPA 420-R-16-900. August 2016. Section 2.4.8.1.1 Idle Control Technologies. Pages 2-49 through 2-53. 9 Cullen, Angela. Memo to the Docket: Proposed Idle Reduction Technology Package Benefits. August 2019. Combination technology Tamper-resistant Calculated credit (%) GEM input Adjustable Calculated credit (%) GEM input Battery APU & Heater 6.3 6 5.1 5 Diesel APU & Heater 5.0 5 4.0 4 Stop-Start & Heater 4.6 5 3.7 4 3. Manufacturer Testing of Production Vehicles The regulations will require tractor manufacturers to annually chassis test five production vehicles over the GEM cycles to verify that relative reductions simulated in GEM are being achieved in actual production. See 40 CFR 1037.665. We do not expect absolute correlation between GEM results and chassis testing. GEM makes many simplifying assumptions that do not compromise its usefulness for certification but do cause it to produce emission rates different from what would be measured during a chassis dynamometer test. Given the limits of correlation possible between GEM and chassis testing, we would not expect such testing to accurately reflect whether a vehicle was compliant with the GEM standards. Therefore, § 1037.665 does not apply compliance liability to such testing. Rather, this testing will be for informational purposes only. (81 FR 73638, October 25, 2016.) The regulation also allows manufacturers to request approval of alternative testing “that will provide equivalent or better information.” Manufacturers have asked us to clarify this allowance. Therefore, we are proposing to explicitly allow CO 2 data from in-use operation, and CO 2 data from manufacturer-run on-road testing. To qualify, the vehicles would need to be actual production vehicles rather than custom-built prototype vehicles. Such vehicles could be covered by testing or manufacturer owned exemptions but would need to be produced on an assembly line or other normal production practices. Manufacturers would also need to ensure test methods are sufficiently similar from year to year to allow for a meaningful analysis of trends. 4. Canadian Vehicle Standards During the Phase 2 rulemaking, Environment and Climate Change Canada (ECCC) emphasized that the highway weight limitations in Canada are much greater than those in the U.S. Where the U.S. federal highways have limits of 80,000 pounds gross combined weight, Canadian provinces have weight limits up to 140,000 pounds. This difference could potentially limit emission reductions that could be achieved if ECCC were to fully harmonize with the U.S.'s HD Phase 2 standards because a significant portion of the tractors sold in Canada have GCWR (Gross Combined Weight Rating) greater than EPA's 120,000-pound weight criterion for “heavy-haul” tractors. EPA addressed this in Phase 2 by adopting provisions that allow the manufacturers the option for vehicles above 120,000 pounds GCWR to meet the more stringent standards that reflect the ECCC views on appropriate technology improvements, along with the powertrain requirements that go along with higher GCWR (see 81 FR 73582, October 25, 2016). Vehicles in the 120,000 to 140,000 pound GCWR range would normally be treated as simple “heavy haul” tractors in GEM, which eliminates the GEM input for aerodynamics. However, vehicles certified to the optional standards would be classified as “heavy Class 8” tractors in GEM, which then requires an aerodynamic input. Nevertheless, they both use the heavier payload for heavy haul. ECCC has since adopted final standards for these tractors, which differ from the optional standards finalized in Phase 2. 10 Since the purpose of these standards was to facilitate certification of vehicles intended for Canada, we are now proposing to revise our optional standards to be the same as the final ECCC standards. The proposed standards can be found in § 1037.670. Note that these standards are not directly comparable to either the normal Class 8 standards or the heavy haul standards of § 1037.106 because GEM uses different inputs for them. 10 Regulations Amending the Heavy-duty Vehicle and Engine Greenhouse Gas Emission Regulations and Other Regulations Made Under the Canadian Environmental Protection Act, 1999: SOR/2018-98, Canada Gazette, Part II, Volume 152, Number 11, May 16, 2018. ECCC has also adopted new standards for tractors in the 97,000 to 120,000-pound GCWR category. We request comment on the need for special provisions for these vehicles. 5. Vehicle Model Year Definition For Phase 2 tractors and vocational vehicles, the vehicle's regulatory model year is usually the calendar year corresponding to the date of manufacture. However, the Phase 2 regulations allow the vehicle's model year to be designated to be the year before the calendar year corresponding to the date of manufacture if the engine's model year is from an earlier year. After promulgation of the FRM, it became apparent that the Phase 2 vehicle model year definition does not allow starting a vehicle model year before January 1st of the named model year if the engine model year also begins in the earlier year. For example, if a manufacturer would start its 2024 engine model year in December 2023, the definition would not allow vehicles produced in 2023 to be model year 2024. To address this issue, EPA is proposing to add back the option to allow the vehicle's model year to be designated to be the year after the calendar year of manufacture. In other words, we would allow manufacturers to meet standards earlier to ensure that engine and vehicle model years are aligned. Model years would still be constrained to reflect annual (rather than multi-year) production periods and include January 1 of the named year. 6. Compliance Margins for GEM Inputs The regulations at 40 CFR 1037.620(d) allow components manufacturers to conduct testing for vehicle manufacturers, but they do not specify restrictions for the format of the data. Vehicle manufacturers have raised concerns about component manufacturers including compliance margins in GEM inputs—in other words, inputting a value that is significantly worse than the tested result. They state that many component suppliers are providing GEM inputs with compliance margins, rather than raw test results. However, when stacked together, the compliance margins would result in inappropriately high GEM results that would not represent the vehicles being produced. In addressing this concern, it is important to distinguish between engine fuel maps (which are certified separately) and other GEM inputs that are not certified. As is discussed in Section I.B.2, certified engine fuel maps are expected to include compliance margins (albeit small margins). However, EPA did not expect each GEM input to have a significant compliance margin of its own. (Note that the aerodynamic bin structure serves to provide an inherent compliance margin for most vehicles.) Rather, we expected the certifying OEM to include compliance margins in their Family Emission Limits (FELs) relative to the GEM outputs. For vehicle GHG standards, the primary role for FEL compliance margins is to protect against Selective Enforcement Audit (SEA) failures. Without a compliance margin under the Phase 2 regulations, normal production variability would cause some vehicles to fail, which would require the testing of additional vehicles. Even if the family ultimately passed the SEA, it would probably require the manufacturer to test a large number of vehicles. However, because SEAs for particular components would not target GEM inputs for other components, a modest compliance margin for the FEL would be sufficient to cover the full range of components. While we are not proposing explicit changes with respect to compliance margins, we are proposing to revise the procedures for conducting an SEA for an axle or transmission apart from a specific vehicle. These revisions would further obviate a need for component-specific compliance margins. Although we do not believe that suppliers should normally include compliance margins when providing test data to OEMs for GEM inputs, we do believe they should provide to OEMs some characterization of the statistical confidence they have in their data. This would allow the OEM to apply an appropriate overall compliance margin for their FEL. Finally, none of this is intended to discourage suppliers and OEMs from entering into commercial agreements related to the accuracy of test results or SEA performance. 7. SEAs for Axles and Transmissions Under 40 CFR 1037.320, a selective enforcement audit (SEA) for axles or transmissions would consist of performing measurements with a production axle or transmission to determine mean power loss values as declared for GEM simulations, and running GEM over one or more applicable duty cycles based on those measured values. The axle or transmission is considered passing for a given configuration if the new modeled emission result for every applicable duty cycle is at or below the modeled emission result corresponding to the declared GEM inputs. As described below, EPA is proposing to revise the consequences where an axle or transmission does not pass. We believe special provisions are needed for axles and transmissions given their importance as compliance technologies and a market structure in which a single axle or transmission could be used by multiple certifying OEMs. Under the existing SEA regulations, if an axle or transmission family from an independent supplier fails an SEA, vehicle production could be disrupted for multiple OEMs and have serious economic impacts on them. We are proposing new regulatory text that would minimize the disruption to vehicle production. Under the proposal, if the initial axle or transmission passes, then the family would pass, and no further testing would be required. This is the same as under the existing regulations. However, if the initial axle or transmission does not pass, two additional production axles or transmissions, as applicable, would need to be tested. Upon completion of the third test, the results of the three tests would be combined into a single map. This would become the official test result for the family. In other words, this proposed approach would correct the data used by the OEM for their end-of-year report. We request comment on whether there are other components for which this approach would be appropriate. 8. Weight Reduction The regulations in 40 CFR 1037.520 include tables to calculate weight reduction values for using certain lightweight components. The sum of the weight reductions is used as an input to GEM. EPA is proposing two changes to Table 8 of that section. First, we are proposing to allow manufacturers to use the heavy heavy-duty (HHD) values for medium heavy-duty (MHD) vehicles with three axles ( i.e., 6x4 and 6x2 configurations). These MHD vehicles typically share chassis components with HHD vehicles, but are classified as MHD because of the lighter duty engines. Second, we are proposing to add a footnote to the table to clarify that the weight reduction values apply per vehicle (instead of per component) unless otherwise noted. 9. Electric and Hybrid Vehicles in Vocational Applications Manufacturers have expressed concern that the Phase 2 regulations are not specific enough regarding how to classify hybrid vocational vehicles (see 40 CFR 1037.140). This is not an issue for tractors, which are classified based on GVWR. However, vocational vehicles are generally classified by the class of the engines. Obviously, this approach does not work for electric vehicle without engines. This approach could also misrepresent a hybrid vehicle that is able to use an undersized engine. To address these problems, we are proposing to revise 40 CFR 1037.140(g) to clarify that hybrid vehicles are heavy heavy-duty vehicles if they are either propelled by a heavy heavy-duty engine and all other hybrid and electric vehicles are classified by GVWR class. We request comment on alternative approaches, such as specifying the useful life in hours rather than miles for these vocational vehicles, or allowing electric vehicles to step down one weight class, with justification from the manufacturer. 10. Vocational Vehicle Segmentation The Phase 2 regulatory structure applies the primary vocational standards by subcategory based on drive cycles. The three subcategories are Regional, Multi-purpose, and Urban. Manufacturers are generally allowed to certify vocational vehicles in the particular duty-cycle subcategory they believe to be most appropriate, consistent with good engineering judgment. This process for selecting the correct subcategory is often called “segmentation.” Under this structure, EPA expects manufacturers to choose a subcategory for each vehicle configuration that best represents the type of operation that vehicle will actually experience in use. This is important because several technologies provide very different emission reductions depending on the actual in-use drive cycle. For example, stop-start would provide the biggest emission reductions for urban vehicles and much less reduction for vehicles that operate primary on long intercity drives. Manufacturers have raised concerns about the impact of this structure on their ability to plan for and monitor compliance. They have suggested that more objective and quantitative good engineering judgment criteria would be helpful. In response to these concerns, EPA is proposing an interim “safe harbor” provision for vocational vehicle segmentation. Manufacturers meeting the safe harbor criteria described below would be presumed to have applied good engineering judgment. The first principle of this safe harbor would be that any vehicle could be classified as Multi-purpose. The Multi-purpose duty cycle weighting factors include significant weightings for highway operation, lower speed transient operation, and idle. Thus, it would not generally overvalue an individual technology. The second principle of this safe harbor would be that vehicles not classified as Multi-purpose should not be exclusively Regional or Urban. We are proposing a quantitative measure that evaluates the ratio of Regional vehicles to Urban vehicles within an averaging set. Specifically, ratio of Regional vehicles to Urban vehicles must be between 1:5 and 5:1. An equivalent way of saying this is that the number of Regional vehicles divided by the number of Urban vehicles would need to be between 0.20 and 5.0. We believe this safe harbor would be consistent with the intent of the Phase2 program and would not allow manufacturers to reduce the effective stringency the standards. Nevertheless, EPA requests comment on this approach overall and the range of acceptable ratios. We also request comment on how to handle specialty manufacturers that have a less diverse product offerings. Finally, we request comment on the need for the subcategory on the label and whether or not we should allow manufacturers to reassign subcategories for their end-of-year ABT reports. 11. Early Certification for Small Manufacturers Vehicle manufacturers that qualify as small businesses are exempt from the Phase 1 standards, but must meet the Phase 2 standards beginning in 2022. However, some vehicle families have been certified voluntarily to Phase 1 standards by small manufacturers. In an effort to encourage more voluntary early certification to Phase 1 standards, we are proposing to adopt a new interim provision in § 1037.150(y)(4) for small manufacturers that certify their entire U.S.-directed production volume to the Phase 1 standards for calendar year 2021. If the small manufacturers do so, the proposed provision would then allow these manufacturers to certify to the Phase 1 standards for model year 2022 (instead of the otherwise applicable Phase 2 standards). Early compliance with the Phase 1 standards should more than offset any reduction in benefits for model year 2022 (although the magnitude of any impact on air quality would be small because of the small production volumes that would be involved). The proposed provision would also allow the Phase 1 vehicle credits that small manufacturers generate from model year 2018 through 2022 vocational vehicles to be used through model year 2027. Under the existing regulations, all manufacturers that generate credits under the Phase 1 program are allowed to use such Phase 1 vehicle credits in the Phase 2 vehicle averaging, banking, and trading program, but the credits are subject to the five-year credit life. The limit on credit life can be problematic for small manufacturers with limited product lines which allow them less flexibility in averaging. We believe the longer credit life would provide them the flexibility they would need to ensure all of their products are fully compliant by the time the Phase 2 standards are fully phased in for model year 2027. We request comment on these proposed changes and any potential impact. 12. Other Minor Heavy-Duty Vehicle Amendments EPA is proposing four additional amendments to part 1037: • Self-contained air conditioning units. We are proposing to revise § 1037.115(e) to clarify that it is intended to address air conditioning systems for which the primary purpose is to cool the driver compartment. This would generally include all complete pickups and vans, but not self-contained air conditioning or refrigeration units on vocational vehicles. • Warranty. We are proposing to revise § 1037.120(b) to correct the text with respect to tires and Heavy Heavy-Duty vehicles. • Drayage tractors. We are proposing to revise § 1037.140(aa) to clarify the production limit for drayage tractors under the custom chassis allowance. • Neutral idle. We are proposing to revise § 1037.660(a)(2) to specify the permissible delay before engaging neutral idle when the vehicle is stopped. D. Requests for Comment on Phase 2 Regulations EPA is soliciting comments on other potential amendments, including those described in this Section II.D. We also welcome comments on the need for other technical corrections and clarifications. Readers are reminded to review public comments placed in the docket, which may contain requests for other corrections and clarifications. 1. Vocational Engines and Credits In 40 CFR 1036.150(p), EPA provides special flexibility for engine manufacturers that certify all their model year 2020 engines within an averaging set to the model year 2021 FTP and SET standards and requirements. GHG emission credits those manufacturers generate with model year 2018 through 2024 engines may be used through model year 2030, instead of being limited to a five-year credit life as specified in § 1036.740(d). They will also be allowed to certify model year 2024 through 2026 tractor engines to alternative standards that are slightly higher than the otherwise applicable standards. The choice would be made when certifying MY 2020 engines. Instead of certifying engines to the final year of the Phase 1 engine standards, manufacturers electing the alternative would indicate that they are instead certifying to the MY 2021 Phase 2 engine standard. Because these engine manufacturers would be reducing emissions of engines otherwise subject to the MY 2020 Phase 1 engine standards (and because engine reductions were not reflected in the Phase 1 vehicle program), there would be a net benefit to the environment. These engines would not generate credits relative to the Phase 1 standards (that is, MY 2020 engines would only use or generate credits relative to the pulled ahead MY 2021 Phase 2 engines standards). Because the vehicle standards themselves are unaffected, these voluntary standards would not reduce the GHG reductions or fuel savings of the program. Vehicle manufacturers using the alternative MYs 2024-2026 engines would need to adopt additional vehicle technology ( i.e., technology beyond that projected to be needed to meet the engine standard) to meet the applicable vehicle GHG standards. This means the vehicles would still achieve the same fuel efficiency in use. EPA did not adopt a similar provision for alternative MY 2024-2026 standards for vocational engines due to concerns about windfall credits. However, given our proposed amendment to address these windfall credits (Section I.B.1), we are asking for comment on the possibility of a similar set of alternative standards for vocational engines, as shown in the following table: Model years Medium heavy-duty vocational Heavy heavy-duty vocational 2020-2023 545 g/hp-hr 513 g/hp-hr. 2024-2026 542 g/hp-hr 510 g/hp-hr. As noted in the Phase 2 FRM, EPA views this type of alternative as being positive from the environmental and energy conservation perspectives, while providing significant flexibility for manufacturers that may reduce their compliance costs. (81 FR 73499, October 25, 2016) 2. Stop-Start Overrides Stop-start systems are an important technology to reduce unnecessary idling, such as when a vehicle is stopped at a traffic light. In 40 CFR 1037.660, we specify how these systems must operate in order to qualify for GEM credit. Included among those provisions are allowances for overriding the automatic engine shutdown where it would otherwise create a potential system damage or safety issue for the engine or driver. Manufacturers have asked us to include additional overrides needed to ensure safe and effective vehicle operation. Specifically, they have asked us to consider overrides for the following conditions, which we are requesting comment on: • Driveline engaged (to prevent driveline and/or starter damage) • Automatic transmission not in D (to reduce engine and transmission loading) • Automatic transmission in P or N (to prevent depleting the battery) • Turn signal activated (to prevent engine stop with the vehicle in intersection) • Hazard warning signal activated (to prevent engine stop during limp-home mode) • SCR thawing (to allow thawing of frozen DEF) • High steering angle (to avoid steering wheel kickback during engine start) • ABS wheel speed sensor failure (to ensure detection of vehicle speed) • Hard braking event (to avoid startling the driver after an event) • Road grade greater than 7% (to prevent vehicle rollback) 3. Delegated Assembly In 40 CFR 1037.621, EPA specifies provisions to allow manufacturers to ship incomplete vehicles and delegate the final assembly to another entity. Manufacturers have expressed the concern that these “delegated assembly” requirements are too burdensome in some cases, particularly in cases such as auxiliary power units and natural gas fuel tanks. EPA requests comment on this issue. 4. Certification Reporting Requirements EPA requests comment on whether and how to revise the text to simplify or clarify the provisions in 40 CFR 1037.205 that require the inclusion of GEM results and credit projections in applications for certification. 5. Mild Hybrid Certification Under the Phase 2 regulations, manufacturers must conduct powertrain testing if they wish to take credit for hybrid systems, including mild hybrid systems. However, manufacturers have expressed concerns about the cost of powertrain testing and that the existing procedure may not measure improvements from certain mild hybrid systems. EPA requests comment on alternative means of evaluating mild hybrids. Manufacturers have asked EPA to consider the following options: • Allow manufacturers to test a powertrain and apply analytically-derived scaling factors to others ( e.g., scale by fraction of battery capacity or motor capacity) under 40 CFR 1037.235(h). • Allow manufacturers to use international test procedures for battery capacity, motor power, and motor efficiency. • Provide smaller credit (potentially with a volume limit and/or only for limited time) in exchange for less testing ( e.g., reduced benefit when using the simplified model spreadsheet that is available under docket no. EPA-HQ-OAR-2014-0827-2109). 6. Transmission Calibrations Manufacturers with advanced transmission calibrations may use the powertrain test option in § 1037.550 to demonstrate the performance of their transmissions. We adopted this option to provide an incentive for the development of advanced transmissions with sophisticated calibrations. Transmission manufacturers have developed some new efficient calibrations, but must also maintain less efficient calibrations to address special types of operation. Due to concerns about resale value, most customers want to retain the ability to select the correct calibration for their operation. For transmissions with such selectable calibrations, § 1037.235(a) requires that they test using the worst-case calibration, which can undermine the incentive to continue improving the calibrations. Therefore, we are requesting comment on allowing manufacturers to measure both the best- and worst-case calibrations and weight them based on survey data, or other appropriate means. Commenters are encouraged to address whether such an allowance would change the effective stringency of the standards. 7. Data Requirements for Hydrogen-Fueled Vehicles We request comment on whether special provisions are needed for hydrogen-fueled vehicles. Currently GEM simulation is required for these vehicles, although by using a non-carbon fuel, simulating the vehicle with GEM would result in zero CO 2 emissions. We request comment on whether or not to change our current approach. E. Other Heavy-Duty Highway Amendments This proposed rule includes other amendments related to heavy-duty highway engines. For example, we are updating the regulations for certification fees as described in Section III.C. We are also proposing or soliciting comment on additional amendments as described in the following sections. 1. Onboard Diagnostics (OBD) EPA's OBD regulations for heavy-duty engines are contained in 40 CFR 86.010-18, which was promulgated February 24, 2009 (74 FR 8310). Although these regulations were originally harmonized with CARB's OBD program, CARB has made changes to their regulations which EPA has not adopted. In several cases, CARB has added flexibility to its regulations. We are requesting comment generally on the differences between EPA and CARB regulations, in addition to the specific issues identified below. More recently CARB has proposed additional revisions and is expected to finalize them this year. 11 We also request comment on these more recent CARB changes. 11 Information is available at https://ww2.arb.ca.gov/rulemaking/2018/heavy-duty-board-diagnostic-system-requirements-2018 . We request comment on the new definitions proposed by CARB at 13 CCR 1971.1(c), including the definitions for “alternate phase-in”, “diagnostic or emission critical electronic control unit”, and “smart device”. EPA is requesting comment on California's approach to approving deficiencies during a model year. In § 1971.1(k)(6.1.1) of their regulations, CARB states: The manufacturer may request a retroactive deficiency until either of the following dates, whichever is later: (A) When the last affected engine or vehicle is produced, or on December 31 of the calendar year for which the model year is named, whichever is sooner; or (B) 6 months after commencement of the start of engine production or vehicle production, whichever is later. Our current regulations do not allow for retroactive deficiencies. EPA is requesting comment on whether to adopt CARB's approach. We are proposing to adopt the CARB 5% threshold for misfire in § 86.010-18(g)(2), and to adopt the additional flexibility provided by CARB for misfires in 13 CCR 1971.1(e)(2.3.3). This would allow manufacturers to not detect misfires under certain conditions, such as during aftertreatment regeneration and some low temperature operation. We are proposing to revise our in-use compliance standards in § 86.010-18(p) to reflect the CARB approach for minimum ratios for representative samples. Under the proposed text, an OBD system would not be considered noncompliant unless a representative sample indicates the in-use ratio is below 0.088. CARB has developed reporting templates for its OBD requirements. EPA is proposing to allow manufacturers to use these templates for reporting to EPA, and we are requesting comment on whether regulatory changes are needed. See CARB Mail-Out #MSC 09-22 as amended on 18-Apr-2019. Our OBD regulations rely on several standard procedures developed by SAE International, as specified in § 86.010-18(k). The regulations also reference a standard of the International Organization for Standardization (ISO). We request comment on the need to update these procedures to more recent versions as summarized below. SAE procedure Version currently cited Latest version SAE J1930 2002 2017 SAE J1939 2007 2017 SAE J1939-13 2004 2016 SAE J1939-73 2006 2017 SAE J1962 2002 2016 SAE J1978 2002 2002 SAE J1979 2007 2017 SAE J2012 2002 2016 SAE J 2403 2007 2014 ISO 15765-4:2005(E) 2005 2011 In § 86.010-18(l), EPA specifies testing requirements for demonstrating the performance of monitoring systems. The amount of testing required depends on the number of engine families a manufacturer certifies in a given model year. CARB regulations include equivalent requirements, and our intent is to allow the use of test data generated for CARB. We are proposing to revise our regulations to state that CARB-certified configurations do not count as separate engine families for the purposes of this provision. EPA is proposing to revise § 86.010-18(a) and (m) to allow a simplified carryover OBD certification path intended for special engine families, such as those certified for export to Canada. This proposed provision is similar to the allowance to show compliance with § 86.010-18 based on CARB certification. To make use of either alternative, the manufacturer must demonstrate to the Administrator how the OBD system they intend to certify meets the intent behind all the requirements of § 86.010-18. These amendments address heavy-duty engines used in vehicles with GVWR above 14,000 pounds. We request comment on the need for similar changes for engine-certified heavy-duty engine families subject to 40 CFR 86.007-17 and 86.1806-17. 2. Smoke Standards and Smoke Measurement Procedures Diesel heavy-duty highway engines have been subject to smoke standards in addition to brake-specific emission standards for many years. The current exhaust emission standards for particulate matter (PM) cause manufacturers to apply calibrations and emission control strategies that reduce PM from the exhaust to very low levels. There is some relationship between brake-specific PM emissions and smoke, but they are not inherently linked. Nevertheless, modern engines with very low PM emissions have very low smoke levels when properly maintained. Thus, we do not believe smoke standards achieve any emission reductions beyond those that result from DPF-forcing PM standards. Manufacturers submit smoke data with certification, but smoke testing is not required for selective enforcement audits with production engines. Some state programs continue to rely on smoke measurement to screen for high-emitting trucks. However, these state testing programs are separate from EPA certification, so we do not expect the state programs to depend on EPA certification for smoke standards. We therefore request comment on removing the smoke standard as a certification requirement for heavy-duty highway engines. We particularly request comment on the EPA smoke standard and its relationship to state testing programs. There are also questions about the smoke test procedures. The smoke test procedures are specified in 40 CFR part 86, subpart I. These procedures were first adopted almost 50 years ago and have remained largely unchanged since that time. They currently apply for locomotives (40 CFR part 1033) and some land-based nonroad diesel engines (40 CFR part 1039). To the extent these procedures continue to apply, we may undertake a future rulemaking to update these procedures and include them in 40 CFR part 1065 along with the other test procedures for measuring exhaust emissions from test engines. We request comment on appropriate changes to ensure that these measurement procedures reflect currently available instruments and practices, without causing the measured values to redefine the stringency of existing standards. 3. Migration From 40 CFR Part 86, Subpart A EPA created 40 CFR part 86 in 1976 to reorganize emission standards and certification requirements for light-duty and heavy-duty highway vehicles and engines. In 1985, EPA adopted new standards for heavy-duty highway engines, codifying the standards in 40 CFR part 86, subpart A, along with the standards and certification procedures for light-duty vehicles and light-duty trucks. 12 Since then, EPA has adopted several rules to set new and more stringent standards for both light-duty and heavy-duty emission control programs and to add or revise certification procedures. However, the original regulatory structure was not well-suited to handle the number of revisions that occurred over time. 12 Emission standards for heavy-duty highway engines were first adopted by the Department of Health, Education, and Welfare in the 1960s. These standards and the corresponding certification and testing procedures were codified at 45 CFR part 1201. In 1972, shortly after EPA was created as a federal agency, EPA published new standards and updated procedures while migrating the regulations to 40 CFR part 85 as part of the effort to consolidate all EPA regulations in a single location. To improve clarity for regulated parties, EPA has been planning to migrate the highway heavy-duty engine standards and certification requirements to 40 CFR part 1036. 13 We expect to propose that migration in a separate rulemaking. The general approach will be to keep the essential regulatory elements in 40 CFR part 86, subpart A, but to streamline and update the regulatory provisions to align with best practices and other current provisions that apply for nonroad engines (such as 40 CFR parts 1033, 1039, and 1042). We believe this technical amendment rulemaking is a good opportunity to solicit input on principles and opportunities for eventually adopting those updated regulations in 40 CFR part 1036. 13 40 CFR part 1036 was created in 2011 as part of the Phase 1 GHG rulemaking (76 FR 57381, September 15, 2011). The migration of regulatory provisions to 40 CFR part 1036 is planned for a future rulemaking because it necessitates a thorough investigation of the provisions that currently apply to heavy-duty engines under 40 CFR part 86. A memo in the docket for this proposal describes a range of possible regulatory amendments we could eventually adopt to reorganize the provisions within 40 CFR part 86, subpart A, eliminate obsolete content, and improve the readability of the remaining provisions. 14 We request comment on those regulatory changes, and on the value of making these changes in this rulemaking, considering that these changes will apply only for the limited time that 40 CFR part 86, subpart A, continues to apply. 14 “Draft Regulatory Text to Update and Reorganize 40 CFR part 86, subpart A”, EPA memorandum from Alan Stout to Docket EPA-HQ-OAR-2019-0307, January 23, 2020. III. Other Amendments A. Ethanol-Blend Test Fuels for Nonroad Spark-Ignition Engines and Vehicles, Highway Motorcycles, and Portable Fuel Containers EPA adopted exhaust and evaporative emission standards for gasoline-fueled nonroad engines, vehicles, and equipment before there was a federal gasoline test fuel with 10 percent ethanol (E10). Most of those programs therefore relied on testing with neat gasoline (E0) or with a splash-blended mix of neat gasoline and ethanol to make E10. In the meantime, EPA adopted a federal gasoline test fuel with 10 percent ethanol for testing motor vehicles (79 FR 23414, April 28, 2014). California ARB adopted its own specification for an E10 test fuel for testing motor vehicles, referred to as “LEV III E10.” California ARB revised its nonroad emission control programs to require manufacturers to start using LEV III E10 test fuel for certification starting in model year 2020, without allowing for carryover of previous data from testing with neat gasoline. California ARB's move to require use of LEV III E10 test fuel for certification has led manufacturers to express a concern about the test burden associated with separate testing to demonstrate compliance with EPA and California ARB emission standards. The concern for aligning test requirements related to test fuel applies for marine spark-ignition engines (40 CFR part 1045), nonroad spark-ignition engines above 19 kW (40 CFR part 1048), and recreational vehicles (40 CFR part 1051). 15 We expect a similar situation to apply for highway motorcycles in the 2022-2025 time frame based on California ARB's plans for further rulemaking activity. In addition, we believe it is best to update evaporative emission test procedures for equipment using nonroad spark-ignition engines (40 CFR part 1060) to allow for using EPA' specified E10 test fuel instead of relying on splash-blending ethanol with EPA's specified E0 gasoline test fuel (known as indolene). 15 EPA adopted amendments to address these concerns for nonroad spark-ignition engines at or below 19 kW in an earlier rulemaking (80 FR 9114, February 19, 2015). We have issued guidance for marine spark-ignition engines (40 CFR part 1045) 16 and for recreational vehicles (40 CFR part 1051) 17 describing how we may approve certification based on emission measurements with an E10 test fuel. We are proposing to revise 40 CFR parts 1045, 1048, and 1051, consistent with the recently issued guidance documents, to allow for certification based on emission measurements with EPA's E10 test fuel without requiring EPA approval, and without adjusting emission standards to account for fuel effects. For marine spark-ignition engines (40 CFR part 1045), this merely replaces the existing provision allowing for the alternative of using a splash-blended E10 test fuel. For recreational vehicles (40 CFR part 1051) and Large SI engines (40 CFR part 1048), naming EPA's E10 specification as the alternative test fuel is a new provision. As originally adopted for Marine SI engines, EPA would always be able to do confirmatory testing with either the original E0 test fuel, or the manufacturer's selected alternative fuel. 16 “Marine Spark Ignition Engine Certification Testing with California ARB E10 Test Fuel,” EPA guidance document CD-18-15, December 24, 2018. 17 “Off-Highway Recreational Vehicle Certification Testing with California ARB E10 Test Fuel,” EPA guidance document CD-19-03, April 22, 2019. We are also proposing to allow the same approach for certification based on emission measurements with EPA's E10 test fuel for highway motorcycles (including EPA confirmatory testing with either E0 or E10). Manufacturers may want to test with California ARB's LEV III E10 test fuel instead of EPA's E10 test fuel. The two sets of fuel specifications are nearly identical, except that the EPA E10 test fuel has a higher volatility. For testing hot-stabilized engines, volatility has a very small effect on exhaust emissions. As a result, we would expect to approve a manufacturer's request to use LEV III E10 test fuel instead of EPA's E10 test fuel under 40 CFR 1065.701(b). This provision allows EPA to approve a different test fuel if it does not affect a manufacturer's ability to show that its engines will comply with all applicable emission standards using the fuel specificed in the subpart. This would apply if fuel's effect on emissions is small enough to allow for using the test results to show that engines would meet applicable emission standards with the specified fuel. Since there are no appreciable fuel effects on exhaust emissions between EPA's E10 test fuel and LEV III E10 test fuel, we would expect this approval process to be straightforward. We expect this approach of allowing E10 as an alternative test fuel to adequately address concerns for the identified sectors. Many of these engines have closed-loop fuel controls that reduce the effect of fuel variables on exhaust emissions. Many also have relatively large compliance margins relative to the standards that apply. These factors help manufacturers confidently test with E10 as an alternative fuel, knowing that they continue to be liable for meeting emission standards on the specified E0 test fuel. EPA has an interest in transitioning all emission measurements for gasoline-fueled engines to an E10 test fuel. However, modifying the emission control program by allowing (or requiring) a complete compliance demonstration based on an E10 test fuel would require a more careful assessment of the fuel effects from the ethanol added to the test fuel. Since the ethanol in some cases has significant effects on HC, NO X , and CO emissions, we would need to evaluate the resulting effects on the stringency of the standards. We would generally expect to adopt adjusted standards with the objective of maintaining equivalent stringency. Developing such alternative standards for an E10 test fuel would require a large body of data to adequately capture the fuel effects on emissions for all the different classes of highway motorcycles, for all the different types of nonroad engines and vehicles, and for different kinds of engine technology within the various sectors. We took this approach for nonroad spark-ignition engines below 19 kW by adopting alternative CO standards that apply for testing with LEV III E10 test fuel (78 FR 36397, June 17, 2013). Toward that end, we have prepared a memorandum with a collection of available emission data from nonroad engines and highway motorcycles tested with E0 and E10 test fuels. 18 The data include results from programs conducted by industry associations, EPA efforts with Canadian labs, and other U.S. laboratory data. We solicit additional emission data to further help establish the comparison between the test fuels for different engine types, applications, and technologies. We also request comment on the benefits or concerns with adopting alternative standards that correspond with a change to require E10 test fuel for all testing (both for manufacturers and EPA). Available information suggests that the fuel-related emission effects for technologies across these sectors are much more complex and varied than we observed for Small SI engines. Some technology differences, such as two-stroke vs. four-stroke and naturally aspirated vs. turbocharged, have relatively consistent and predictable fuel-related emission effects. However, some technologies will have fuel-related emission effects that depend on specific design strategies. For example, manufacturers can use electronic controls to optimize for power, fuel economy, low-speed torque, or some other measure of performance. Partial use of closed-loop control of air-fuel ratios is one clear example of this, with the potential to adjust the air-fuel ratio to different setpoints, or to limit closed-loop control only to certain operating conditions. We request comment on how best to account for these design-specific engine technologies in evaluating fuel-related emission effects for each type of engine. 18 “Collection of E0/E10 Emission Data for Current Certified Nonroad Sector Engines and On Highway Motorcycles” EPA memorandum from Cheryl Caffrey to Docket EPA-HQ-OAR-2016-0604, December 6, 2019. The emission effects are most pronounced for CO emissions, but we are also interested in HC and NO X emissions. To the extent that NO X emissions (or HC + NO X emissions) increase to a degree that affects the stringency of the standards, we would consider increasing the numerical level of the standard to maintain equivalent stringency. EPA also specifies test fuels for evaporative emission testing. The gasoline test fuel for measuring permeation emissions from nonroad fuel tanks and fuel lines is a splash-blended E10. The is an E0 test fuel that is blended to reach a 10 percent concentration of ethanol. The splash-blended E10 test fuel is nearly identical to EPA's specified E10 test fuel except for the volatility. EPA's Tier 3 E10 test fuel has a nominal volatility of 9 psi RVP and the splash-blended E10 has a volatility of about 10 psi RVP. 19 We request comment on amending the regulation to allow testing with the pre-mixed E10 test fuel with 9 psi RVP instead of the splash-blended E10 test fuel with 10 psi. In particular, we encourage commenters to share any available data describing how gasoline volatility affects permeation rates. We would not want manufacturers to test with lower fuel volatility if it decreases permeation rates and allows manufacturers to use a less effective control technology. We also request comment on the level of interest that manufacturers or testing organizations would have to be able to use EPA's pre-mixed E10 test fuel in the near term, or at any point in the future. We are concerned about issues related to test burden for manufacturers needing to meet standards, but we invite commenters to share their insights on these questions of permeation chemistry. If the final rule includes an amendment to allow permeation testing with EPA's pre-mixed E10 test fuel, we would also expect to specify that California ARB's LEVIII E10 test fuel is also acceptable for demonstrating compliance with permeation standards (see § 1060.505(c)(2)). 19 Fuel volatility is based on Reid Vapor Pressure (RVP), which generally quantifies a fuel's equilibrium vapor pressure at 100 °F. A fuel with volatility of 9 psi would therefore have an equilibrium vapor pressure of about 9 psi at 100 °F. A different dynamic applies for diurnal testing. This measurement procedure applies for Marine SI fuel tanks and for some Large SI equipment. We currently specify an E0 test fuel with a nominal volatility of 9 psi RVP for diurnal testing in 40 CFR 1060.525. The volume of vapor venting during a diurnal test depends on the volatility of the test fuel. Changing the ethanol content of the fuel without changing the volatility should cause no significant change in the volume of vapor venting during the diurnal test. The specified EPA E10 test fuel has the same volatility as the E0 test fuel, but it has the added ethanol. We request comment on amending the regulation to allow testing with the specified EPA E10 test fuel instead of the E0 test fuel. As described for permeation testing above, we would not want manufacturers to use a test fuel that would decrease vapor pressures and allow manufacturers to use a less effective control technology. We also request comment on the level of interest that manufacturers or testing organizations would have to be able to use EPA's specified E10 test fuel in the near term, or at any point in the future. We specify emission standards and test procedures for portable fuel containers in 40 CFR part 59, subpart F. The test relies on a splash-blended E10 test fuel. California ARB specifies their LEV III gasoline test fuel for the analogous procedures in California, but they allow manufacturers to submit data instead using EPA's specified test fuel. Accordingly, we believe manufacturers do not face the same burden of needing to perform duplicate measurements for the two agencies. We are therefore not proposing to change the EPA test fuel for portable fuel containers. However, we request comment on allowing manufacturers the option of using EPA's specified E10 test fuel to demonstrate compliance with the combined test for diurnal and permeation emissions. B. Removing Obsolete CFR Content EPA first adopted emission standards for light-duty motor vehicles and heavy-duty highway engines in the 1970s. Emission standards for the first categories of nonroad engines started to apply in the 1990s. Each of these programs include emission standards that apply by model year. For most of these programs over time, engines and vehicles were subject to increasingly stringent standards and improved certification and testing requirements. All these standards and regulatory provisions are codified in the Code of Federal Regulations. As time passes, the regulations for past model years become obsolete, but it remains in print until there is a rulemaking change to remove it from print. We are proposing in this rule to remove large portions of this regulatory content that no longer applies. The following sections describe these changes for different sectors. Note that Section III.D describes several amendments to emission control programs for motor vehicles in 40 CFR parts 85 and 86. These amendments include several provisions that also remove obsolete regulatory content. 1. Clean Fuel Fleet Standards (40 CFR Part 88) The Clean Air Act Amendments of 1990 included numerical standards for the Clean Fuel Fleet program that were intended to encourage innovation and reduce emissions for fleets of motor vehicles in certain nonattainment areas as compared to conventionally fueled vehicles available at the time. As originally adopted, those Clean Fuel Fleet standards were substantially more stringent than the standards that applied to vehicles and engines generally. Now that we have begun implementing Tier 3 standards in 40 CFR part 86, subpart S, the Clean Fuel Fleet standards are either less stringent than or equivalent to the standards that apply to vehicles and engines generally. Because the statute continues to require Clean Fuel Fleet standards for state clean-fuel vehicle programs, we cannot simply remove the Clean Fuel Fleet program from the regulations. Rather, we are proposing to implement the Clean Fuel Fleet standards in 40 CFR part 88 with a compliance option where vehicles and engines certified to current standards under 40 CFR part 86 and part 1036 would be deemed to comply with the Clean Fuel Fleet standards as Ultra Low-Emission Vehicles. Further, the Clean Fuel Fleet program as adopted included labeling requirements for engine and vehicle manufacturers to identify compliant engines and vehicles, and a restriction against including such engines or vehicles when calculating emission credits. Both provisions would also no longer be applicable because of the earlier mentioned increased stringency of standards for engines and vehicles, and under the compliance option we are proposing. Therefore, we are also proposing to remove these regulations. This will give clear instructions to vehicle and engine manufacturers as well as states that continue to have Clean Fuel Fleet provisions in their State Implementation Plans or become subject to these requirements in the future under CAA sections 182(c)(4)(A) and 246(a). For states with areas that become subject to the clean-fuel vehicle program requirements in the future based on a new designation as an ozone nonattainment area, the required state implementation plan submission for the program or for a substitute measure is due within 42 months after the effective date of an area's nonattainment designation. The clean-fuel vehicle program requirements apply for ozone nonattainment areas with an initial designation as Serious, Severe, or Extreme. For marginal and moderate ozone nonattainment areas that are reclassified as Serious, Severe, or Extreme, the required state implementation plan submission for the program or for a substitute measure is due on the date specified in the EPA rulemaking finalizing the area's reclassification. The Clean Fuel Fleet program also depends on vehicle classifications that include Zero Emission Vehicles and Inherently Low-Emission Vehicles. We are therefore preserving these defined terms in 40 CFR part 88. We are proposing to consider as Zero Emission Vehicles all electric vehicles and any vehicle that does not emit NO X , PM, HC, CO, or formaldehyde (including evaporative emissions). We are proposing to simplify the definition of Inherently Low-Emission Vehicles to mean any certified vehicle that is designed to not vent fuel vapors to the atmosphere. 2. Legacy Nonroad Standards (40 CFR Parts 89 Through 94) The 1990 amendments to the Clean Air Act authorized EPA to set emission standards for nonroad engines. This led to a series of rulemakings to adopt emission control programs for different nonroad sectors. From 1994 through 1999, EPA adopted these emission control programs in 40 CFR parts 89, 90, 91, 92, and 94 (all part of Subchapter C). Starting in 2002, EPA adopted emission standards for additional nonroad emission control programs in a new subchapter, which allowed for improved organization and harmonization across sectors. We codified these new standards and related provisions in 40 CFR parts 1048, 1051, 1065, and 1068 (all part of Subchapter U). Since then, we have migrated the “legacy” emission control programs from Subchapter C to Subchapter U. In each case, the migration corresponded to new emission standards and substantially updated compliance and testing provisions. This applies for the following sectors: Sector Legacy regulation Current regulation Land-based nonroad diesel engines 40 CFR part 89 40 CFR part 1039. Nonroad spark-ignition engines at or below 19 kW 40 CFR part 90 40 CFR part 1054. Marine spark-ignition engines 40 CFR part 91 40 CFR part 1045. Locomotives and locomotive engines 40 CFR part 92 40 CFR part 1033. Marine diesel engines 40 CFR part 94 40 CFR part 1042. As a result of this migration, engine manufacturers have not certified engines under the legacy parts for the last 5-10 years. Removing these legacy parts reduces the cost to the Agency and prevents confusion for readers who think that the provisions still apply. While EPA's engine certification programs don't rely on these obsolete provisions, the new programs refer to the legacy parts for some specific provisions. For example, the new standard-setting part for each type of engine/equipment allows manufacturers to continue to certify carryover engine families based on test data from procedures specified in the legacy parts. We are not proposing to discontinue further use of carryover data from engines originally certified under the legacy parts. On the other hand, this provision will gradually sunset itself as manufacturers update engine designs and perform new testing for their engine families to meet current standards. Considering California's initiative to disallow carryover for nonroad spark-ignition engines starting in model year 2021, we request comment on taking a more direct approach that would sunset carryover based on testing performed according to the legacy parts. Another example of relying on the legacy parts in the new regulations is emission credits generated under the legacy parts. In most cases, current programs either disallow using those credits for certification, or they allow it without keeping separate accounts for credits generated under the legacy parts. We are proposing no changes where credits from legacy parts are either unavailable or indistinguishable from currently generated credits. One exception is for land-based nonroad diesel engines certified under 40 CFR parts 89 and 1039. Current provisions in § 1039.740 allow for limited use of Tier 2 and Tier 3 credits from part 89 for certifying Tier 4 engines. However, these constraints are not time-limited. Now that the Tier 4 standards have been in place for several years, we would be interested in simplifying the credit accounting by sunsetting these provisions. We therefore request comment on the extent to which any manufacturers might rely on continued use of Tier 2 or Tier 3 emission credits for certifying their land-based nonroad diesel Tier 4 engines. We are also aware that other federal and state regulations and compliance programs include numerous references to 40 CFR parts 89 through 94. To address this, we are proposing to replace the full text of regulations in the legacy parts with a paragraph describing the historical scope and purpose for each part. The remaining paragraph also directs readers to the new regulations that apply in Subchapter U, and clarifies how the regulatory requirements transition to the new content. As an example, the statute and regulations prohibit tampering with certified engines throughout an engine's lifetime, even if the original text describing that prohibition no longer resides in its original location in the Code of Federal Regulations. We are also proposing to capture the emission standards from the legacy parts as reference material in an appendix in the appropriate CFR parts. This allows for readily citing the historical standards in our own emission control programs, and in any other federal or state regulations or compliance materials that depend on citing emission standards that are no longer current for purposes of gaining EPA certification as part of our nonroad emission control program. In addition to removing references to the legacy parts, we are taking the opportunity to remove additional obsolete content from the newer regulations. Most of these changes were adopted to address temporary concerns as part of transitioning to new standards or other new requirements. We adopted these changes in isolated regulatory sections as “interim provisions.” Most of these interim provisions have been obsolete for several years. 20 20 A docket memo includes redline text to highlight all the changes to the regulations in the proposed rule. This is especially helpful for reviewing provisions that we are removing from the CFR. See “Redline Document Showing Proposed Changes to Regulatory Text in the Heavy-Duty Greenhouse Gas Amendments”, EPA memorandum from Alan Stout to Docket EPA-HQ-OAR-2019-0307. For obsolete provisions we are removing, see especially 40 CFR 1027.105, 1033.150, 1042.145, 1045.145, 1048.145, 1051.145, 1054.145, and 1054.625. References to the legacy parts are especially common for stationary engines EPA regulates under 40 CFR part 60, subpart IIII and subpart JJJJ. The emission standards for stationary engines in many cases rely on current or past nonroad emission standards in 40 CFR parts 89, 90, and 94. Including all the iterations of these emission standards as reference material allows us to preserve the existing set of standards and requirements for stationary engines. The proposed regulations include numerous amendments to 40 CFR part 60 to change regulatory cites from the legacy parts to the new regulatory parts in Subchapter U. Most of the changes for stationary engines in 40 CFR part 60 are intended to update references without changing standards or other provisions. We are proposing two more substantive changes. First, we are proposing to allow manufacturers of emergency stationary compression-ignition internal combustion engines and stationary emergency spark-ignition engines to certify using assigned deterioration factors. Since these emergency engines generally serve in standby status in anticipation of emergency situations, they often have lifetime operation that is much less extensive than non-emergency engines. Assigned deterioration factors would allow manufacturers to demonstrate the durability of emission controls without performing testing that might otherwise exceed the operating life of the engines being certified. Second, stationary spark-ignition engines are currently subject to emission standards and certification procedures adopted under 40 CFR part 90 for Phase 1 engines. Revising the requirements for these engines to instead rely on the certification procedures in 40 CFR part 1054 requires that we identify the Phase 1 standards as not including the following provisions that apply for Phase 3 engines (as noted in the proposed regulatory text for Appendix I of part 1054): • The useful life and corresponding deterioration factors. • Evaporative emission standards. • Altitude adjustments. • Warranty assurance provisions in § 1054.120(f). • Emission-related installation instructions. • Bonding. C. Certification Fees (40 CFR Part 1027) EPA is making several minor changes in 40 CFR part 1027 to update the procedures and align the instructions with current practices. None of these changes involve change or reconsideration of fee policies. We are proposing the following changes: • Correcting the name of the compliance program. • Replacing the schedule of fees from 2005 with the fees that apply for applications submitted in 2020. • Revising the timeline for announcing adjusted fees for the upcoming year from a January 31 deadline to a March 31 deadline. This will allow for a more orderly process of calculating the new fees using the information from the previous year. • Correcting the equation for non-evaporative certificates to no longer apply the inflation adjustment to operating costs. This corrects a publishing error that mistakenly introduced parentheses in the equation. • Correcting the internet address for the consumer price index used for inflation adjustments. • Removing the sample calculation for determining fees for 2006. • Revising submission and payment instructions to refer only to ele [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2020-05963. Public record. Not legal advice.