Vehicles must meet evaporative and refueling emission standards as specified in this section. These emission standards apply for heavy duty vehicles above 14,000 pounds GVWR as specified in § 86.1801 . These emission standards apply for total hydrocarbon equivalent (THCE) measurements using the test procedures specified in subpart B of this part, as appropriate. Note that § 86.1829 allows you to certify without testing in certain circumstances. These evaporative and refueling emission standards do not apply for electric vehicles, fuel cell vehicles, or diesel-fueled vehicles, except as specified in paragraph (b) of this section. Unless otherwise specified, MDPVs are subject to all the same provisions of this section that apply to LDT4.
(a)Tier 3 evaporative emission standards. Vehicles may not exceed the Tier 3 evaporative emission standards, as follows: (1) Measure emissions using the test procedures of subpart B of this part, as follows: (i) Follow the vehicle preconditioning and exhaust testing procedures as described in subpart B of this part.(ii) Measure diurnal, running loss, and hot soak emissions as shown in § 86.130 . This includes separate measurements for the two-diurnal test sequence and the three-diurnal test sequence; however, gaseous-fueled vehicles are not subject to any evaporative emission standards using the two-diurnal test sequence.(iii) For gasoline-fueled vehicles, use E10 test fuel as required in § 86.113 , except as specified in this section.(iv) Emissions are generally measured with a flame ionization detector (FID). In the case of rig, diurnal, hot soak, and running loss testing with E10 test fuel, multiply measured (unspeciated) FID values by 1.08 to account for the FID's reduced response to ethanol. However, you may instead determine total hydrocarbon equivalent for E10 testing based on speciated measurements as described in § 86.143-96(c) . You may use different methods (with or without speciation) for different test elements for a given test vehicle; however, you must always use the same method for diurnal and hot soak testing. In addition, any later testing with vehicles from that evaporative/refueling family must use the same method that was used for the original testing. Similarly, any evaporative/refueling families certified in later model years using carryover data must use the same method that was used for the original testing. We may do testing with or without speciation, but we will apply the 1.08 correction factor to unspeciated measurements for any of these four categories of evaporative emissions only if you also use it to determine your final test results.(2) Diurnal and hot soak emissions may not exceed the Tier 3 emission standards, as follows: (i) The emission standard for the sum of diurnal and hot soak measurements from the two-diurnal test sequence and the three-diurnal test sequence is based on a fleet average in a given model year. You must specify a family emission limit (FEL) for each evaporative family. The FEL serves as the emission standard for the evaporative family with respect to all required diurnal and hot soak testing. Calculate your fleet average emission level as described in § 86.1860 based on the FEL that applies for low-altitude testing to show that you meet the specified standard. For multi-fueled vehicles, calculate fleet average emission levels based only on emission levels for testing with gasoline. You may generate emission credits for banking and trading, and you may use banked or traded credits for demonstrating compliance with the diurnal plus hot soak emission standard for vehicles required to meet the Tier 3 standards, other than gaseous-fueled or electric vehicles, as described in § 86.1861 starting in model year 2017. You comply with the emission standard for a given model year if you have enough credits to show that your fleet average emission level is at or below the applicable standard. You may exchange credits between or among evaporative families within an averaging set as described in § 86.1861. Separate diurnal plus hot soak emission standards apply for each evaporative/refueling emission family as shown for high-altitude conditions. The sum of diurnal and hot soak measurements may not exceed the following Tier 3 standards: Table 1 of § 86.1813-17 -Tier 3 Diurnal Plus Hot Soak Emission Standards
[grams per test]
Vehicle category | Low-altitude conditions-fleet-average | High-altitude conditions |
LDV, LDT1 | 0.300 | 0.65 |
LDT2 | 0.400 | 0.85 |
HLDT | 0.500 | 1 1.15 |
HDV | 0.600 | 1.75 |
1 1.25 g/test for MDPVs.
(ii) Specify FELs as follows:(A) You may specify the low-altitude FEL in increments of 0.025 g above or below the otherwise applicable Tier 3 diurnal plus hot soak standard, up to the maximum values specified in the following table: Table 2 of § 86.1813-17 -Tier 3 FEL Caps for Low-Altitude Testing
Vehicle category | FEL Caps |
LDV | 0.500 |
LLDT | 0.650 |
HLDT | 0.900 |
MDPV | 1.000 |
HDV | 1.4 |
(B) Calculate the FEL for testing at high-altitude conditions based on the difference between the low-altitude FEL and the standard. For example, if a light-duty vehicle was certified with an FEL of 0.400 g instead of the 0.300 g standard, the FEL for testing under high-altitude conditions would be 0.75 g (0.65 + 0.10).(iii) Hydrocarbon emissions must not exceed 0.020 g for LDV and LDT and 0.030 g for HDV when tested using the Bleed Emission Test Procedure adopted by the California Air Resources Board as part of the LEV III program. This procedure quantifies diurnal emissions using the two-diurnal test sequence without measuring hot soak emissions. For heavy-duty vehicles with a nominal fuel tank capacity at or above 50 gallons, operate the vehicle over a second full FTP cycle before measuring diurnal emissions. The standards in this paragraph (a)(2)(iii) do not apply for testing at high-altitude conditions. For vehicles with non-integrated refueling canisters, the bleed emission test and standard do not apply to the refueling canister. You may perform the Bleed Emission Test Procedure using the analogous test temperatures and the E10 test fuel specified in subpart B of this part.(iv) Vehicles that become light-duty vehicles based on the change in the definition for "light-duty truck" for Tier 4 vehicles may continue to meet the same evaporative emission standards under this paragraph (a) through model year 2031 as long as they qualify for carryover certification as described in § 86.1839.(v) Vehicles that are no longer medium-duty vehicles based on the change in the definition for "medium-duty passenger vehicles" for Tier 4 vehicles may continue to meet the same evaporative emission standards under this paragraph (a) through model year 2031 as long as they qualify for carryover certification as described in § 86.1839.(3) Running losses may not exceed 0.05 g per mile when measured using the test procedures specified in § 86.134 . This standard does not apply for gaseous-fueled vehicles.(4) Fuel systems for vehicles operating on one or more volatile liquid fuels may not exceed an effective leak diameter of 0.02 inches when measured using the procedure specified in 40 CFR 1066.985 . For vehicles with fuel tanks exceeding 25 gallons nominal fuel tank capacity, you may request our approval for a leak standard greater than 0.020 inches, up to a maximum value of 0.040 inches.(5) The Tier 3 evaporative emission standards start to phase in with model year 2017 for vehicles at or below 6,000 pounds GVWR and with model year 2018 for vehicles above 6,000 pounds GVWR. Table 3 of this section specifies the minimum percentage of each manufacturer's sales in each model year that must be certified to the Tier 3 evaporative emission standards. Calculate annual percentages based on actual nationwide sales of all vehicles subject to standards under this paragraph (a) for the applicable model year; however, if all your FELs for Tier 3 evaporative families are at the applicable standard (neither generating nor using emission credits), the phase-in requirements are based on projected sales. Also, if you certify vehicles above 6,000 pounds GVWR to the Tier 3 evaporative emission standards in model year 2017, you may count projected U.S. sales of those vehicles toward your calculation for meeting the 40 percent requirement in 2017 (numerator only). Manufacturers may meet this requirement using the additional alternative phase-in provisions in paragraph (g) of this section. Vehicles from the identified model years not certified to the Tier 3 evaporative emission standards continue to be subject to the evaporative emission standards specified in § 86.1811-09(e) or § 86.1816-08(d) , including the useful life provisions of § 86.1805-12 . Note that this subjects LDV and LDT1 to a 150,000 mile useful life for evaporative emissions if the vehicles are subject to a 150,000 mile useful life for exhaust emissions. Keep records as needed to show that you meet the phase-in requirements specified in this section. See paragraph (g) of this section for additional provisions that apply for model year 2017 and the rest of the phase-in. Table 3 of § 86.1813-17 -Default Phase-In Schedule for Tier 3 Evaporative Emission Standards
Model year | Minimum percentage of vehicles subject to the Tier 3 standards |
2017 | 401 2 |
2018 | 60 |
2019 | 60 |
2020 | 80 |
2021 | 80 |
2022 | 100 |
1 The phase-in percentage for model year 2017 applies only for vehicles at or below 6,000 pounds GVWR.
2 The leak standard specified in paragraph (a)(4) of this section does not apply for model year 2017.
(6) For model year 2017, exclude vehicle sales from California and section 177 states from the calculation to demonstrate compliance with the phase-in schedule in paragraph (a)(5) or (g) of this section, and from the credit calculation in § 86.1860 .(b)Refueling emissions. Light-duty vehicles, light-duty trucks, and heavy-duty vehicles must meet the refueling emission standards in this paragraph (b) as follows when measured over the procedure specified in § 86.150 : (1) The following implementation dates apply for incomplete heavy-duty vehicles:(i) Refueling standards apply starting with model year 2027 for incomplete heavy-duty vehicles certified under 40 CFR part 1037 and in model year 2030 for incomplete heavy-duty vehicles certified under this subpart, unless the manufacturer complies with the alternate phase-in specified in paragraph (b)(1)(iii) of this section. If you do not meet the alternative phase-in requirement for model year 2026, you must certify all your incomplete heavy-duty vehicles above 14,000 pounds GVWR to the refueling standard in model year 2027.(ii) Refueling standards are optional for incomplete heavy-duty vehicles at or below 14,000 pounds GVWR through model year 2029, unless the manufacturer uses the alternate phase-in specified in paragraph (b)(1)(iii) of this section to meet standards together for heavy-duty vehicles above and below 14,000 pounds GVWR.(iii) Manufacturers may comply with an alternate phase-in of the refueling standard for incomplete heavy-duty vehicles as described in this paragraph (b)(1)(iii). Manufacturers must meet the refueling standard during the phase-in based on their projected nationwide production volume of all incomplete heavy-duty vehicles subject to standards under this subpart and under 40 CFR part 1037 as described in Table 4 of this section. Keep records as needed to show that you meet phase-in requirements. Table 4 of § 86.1813-17 -Alternative Phase-In Schedule for Refueling Emission Standards for Incomplete Heavy-Duty Vehicles
Model year | Minimum percentage of heavy-duty vehicles subject to the refueling standard |
2026 | 40 |
2027 | 40 |
2028 | 80 |
2029 | 80 |
2030 | 100 |
(2) The following refueling standards apply: (i) 0.20 g THCE per gallon of fuel dispensed for vehicles using volatile liquid fuels. This standard also applies for diesel-fueled LDV.(ii) 0.15 g THC per gallon of fuel dispensed for liquefied petroleum gas-fueled vehicles and natural gas-fueled vehicles.(c)Fuel spitback. For vehicles fueled by volatile liquid fuels, fuel spitback emissions may not exceed 1.0 g THCE when measured using the test procedures specified in § 86.146 . The fuel spitback standard applies only to newly assembled vehicles.(e)Auxiliary engines and separate fuel systems. The provisions of 40 CFR 1037.103(g) apply for vehicles with auxiliary engines. This includes any engines installed in the final vehicle configuration that contribute no motive power through the vehicle's transmission.(f)Refueling provisions for gaseous-fueled vehicles. The following provisions apply specifically for gaseous-fueled vehicles: (1) Compressed natural gas vehicles must meet the requirements for fueling connection devices as specified in ANSI NGV1-2006 or CSA IR-1-15 (incorporated by reference in § 86.1 ).(3) With our advance approval, liquefied petroleum gas-fueled vehicles with gauges or valves that can be opened to release fuel or fuel vapor during refueling (such as fixed liquid level gauges) may be tested for refueling emissions without opening such gauges or valves, as outlined in § 86.157-98(d)(2) . We will approve your request if you can show that such gauges or valves will not be open during in-use refueling due to inaccessibility or other design features that would prevent them from opening or make this very unlikely.(g)Alternative phase-in options for Tier 3 evaporative emission standards. You may use any of the following alternative methods to transition to the Tier 3 evaporative emission standards: (1) Starting in model year 2015, you may earn an "allowance" for each vehicle that you certify early under this paragraph (g)(1). For each allowance you earn, you may count it as one compliant vehicle in a later model year during the phase-in period. Calculate the total phase-in percentage in each model year by adding the allowances to the number of compliant vehicles (in the numerator), without increasing total sales (in the denominator). For each allowance you earn, you may alternatively count it as one compliant vehicle under the phase-in schedule described in paragraph (g)(5) of this section, except that you may not use those allowances to increase the value of the phase-in index from any model year by more than 10 percentage points. Vehicles earning allowances under this paragraph (g)(1) may not have an FEL above the applicable Tier 3 standard, and may not generate emission credits for banking or trading. Allowances may not be traded to another company. You may earn allowances under this paragraph (g)(1) for early-compliant vehicles as follows:(i) Model year 2015 and 2016 vehicles at or below 6,000 pounds GVWR meeting the Tier 3 standards in paragraph (a) of this section or the equivalent California standards as specified in paragraph (g)(4) of this section earn allowances, as long as the vehicles are not sold in California or any of the section 177 states.(ii) Model year 2015 through 2017 LDV and LDT above 6,000 pounds GVWR meeting the Tier 3 standards in paragraph (a) of this section or the equivalent California standards as specified in paragraph (g)(4) of this section earn allowances, as long as the vehicles are not sold in California or any of the section 177 states.(iii) Model year 2015 through 2017 MDPV and HDV meeting the Tier 3 standards in paragraph (a) of this section or the equivalent California standards as specified in paragraph (g)(4) of this section earn allowances for vehicles sold in any state.(iv) To the extent that you over-comply with the 40-percent phase-in requirement in model year 2017, you may count your actual U.S. sales exceeding the required number of Tier 3 vehicles as allowances toward meeting the phase-in requirement in 2018 and later model years.(v) For HDV above 10,000 pounds GVWR and at or below 14,000 pounds GVWR that you certify to the refueling emission standards in paragraph (b) of this section in model years 2015 through 2017 and sell outside of California and the section 177 states, a single vehicle may produce two allowances if it is certified to the Tier 3 diurnal plus hot soak standard. Allowances earned under this paragraph (g)(1)(v) may alternatively be used in model years 2018 through 2022 to phase in the refueling standard, except that a single early-compliant vehicle produces only a single allowance.(vi) Complete HDV above 14,000 pounds GVWR and all sizes of incomplete HDV earn allowances as described in paragraph (g)(1)(v) of this section if they are certified to the refueling emission standards in paragraph (b) of this section in model years 2015 through 2021.(2) The following alternative phase-in options apply for model year 2017: (i) You may disregard the percentage phase-in specified in paragraph (a)(5) of this section for 2017 if you choose 50-state certification for all your vehicles meeting the LEV III PZEV evaporative standards in 2017. Under this option, you may not produce a higher-emitting version of those vehicle models for sale outside of California or the section 177 states. Such vehicles may be certified using carryover data under the California program, but they may not generate or use emission credits. LDV and LDT1 that comply under this paragraph (g)(2)(i) may not generate allowances under paragraph (g)(1) of this section, regardless of the calculated percentage of compliant vehicles in model year 2017.(ii) You may comply with the phase-in requirement for model year 2017 by meeting the Tier 3 emission standards for diurnal plus hot soak, running loss, and bleed emissions (or the equivalent set of California standards as allowed in this section) with 20 percent of vehicles at or below 6,000 pounds GVWR, and by meeting the leak standard in paragraph (a)(2)(iii) of this section with 20 percent of vehicles at or below 6,000 pounds GVWR. You may optionally include vehicles above 6,000 pounds GVWR under this paragraph (g)(2)(ii) to calculate the percentage (numerator only) if they meet the leak and/or evaporative emission standards in model year 2017. Vehicles complying with Tier 3 evaporative emission standards may generate or use emission credits relative to the diurnal plus hot soak standard as specified in this section, but they may not generate allowances. You may apply this option and use the alternative phase-in calculation in paragraph (g)(4) of this section, subject to the following conditions: (A) You must meet or exceed the 20 percent threshold for both evaporative emissions and the leak standard.(B) All the vehicles meeting the leak standard must also meet the Tier 3 evaporative emission standards. Through model year 2026, all vehicles meeting the leak standard must also meet the OBD requirements in § 86.1806-17(b)(1) . (C) Determine the appropriate percentage for calculating compliance under paragraph (g)(4) of this section by adding 20 to the percentage of vehicles meeting the Tier 3 evaporative emission standards to account for vehicles meeting the leak standard. Do not increase the percentage based on meeting the leak standard with more than 20 percent of your vehicles in model year 2017.(3) If you certify model year 2021 or earlier vehicles to the LEV III evaporative emission standards in California, you may certify those as Tier 3 vehicles that count toward meeting the phase-in requirements of this section. Such vehicles must still be certified to the high-altitude standards in paragraph (a)(2) of this section and the leak standard specified in paragraph (a)(4) of this section. You may not certify vehicles under this paragraph (g)(3) after model year 2021. Vehicles meeting the LEV III standards may also generate allowances under paragraph (g)(1) of this section; however, these vehicles may generate or use emission credits under this subpart only if they are not used to generate allowances and if they are certified using the Option 2 procedures under the LEV III program (including the bleed emission test). Vehicles may be certified under this paragraph (g)(3) based on the rig test ("Option 1") if they are certified to LEV III standards based on the rig test before model year 2017; this certification option applies through model year 2021. Include these Option 1 vehicles in the calculation of fleet average emissions by using the appropriate Tier 3 emission standard as the FEL. Note that the rig test is considered a diurnal test with respect to the provisions to account for ethanol emissions as described in paragraph (a)(1)(iv) of this section.(4) If you fall short of the phase-in percentage specifications in paragraph (a)(5) of this section, you may designate the requisite number of Tier 2 vehicles as Tier 3 vehicles for purposes of demonstrating compliance with the Tier 3 standards in this section. To do this, factor those Tier 2 vehicles into the Tier 3 fleet-average emission calculation using an FEL that is equal to the applicable diurnal plus hot soak standard from the two-day test sequence. The Tier 3 emission standards do not apply to these Tier 2 vehicles. In addition, you may disregard the phase-in percentages specified in paragraph (a)(5) of this section if you instead comply based on one of the following alternative measures: (i) You may comply with an alternate phase-in schedule described in this paragraph (g)(4)(i). To do this, you must give us a detailed plan for describing how you will meet the alternate phase-in schedule. You comply with the alternate phase-in schedule by calculating an evaporative phase-in index using the following equation that is at or above 1,280 for model years 2017 through 2022 (or 1,040 for model years 2018 through 2022 if you use the provisions of paragraph (g)(2)(i) of this section): Evaporative phase-in index = 6·APP2017 + 5·APP2018 + 4·APP2019 + 3·APP2020 + 2·APP2021 + APP2022
Where:
APP = The phase-in percentage of vehicles meeting the Tier 3 evaporative emission standards for the indicated model year, based on actual sales, as described in paragraph (a)(5) of this section.
(ii) You may comply with an alternate phase-in schedule described in this paragraph (g)(4)(ii). To do this, you must give us a detailed plan for describing how you will meet the alternate phase-in schedule. You comply with the alternate phase-in schedule by calculating an evaporative phase-in index using the following equation that is at or above 420 for model years 2017 through 2022 (or 380 for model years 2018 through 2022 if you use the provisions of paragraph (g)(2)(i) of this section): Evaporative phase-in index = APP2017 + APP2018 + APP2019 + APP2020 + APP2021 + APP2022
Where:
APP = The phase-in percentage of vehicles meeting the Tier 3 evaporative emission standards for the indicated model year, based on actual sales, as described in paragraph (a)(5) of this section.
(5) This paragraph (g)(5) describes an alternative approach to phasing in the evaporative and refueling emission standards for gaseous-fueled vehicles above 8,500 pounds GVWR. Under this alternative phase-in, you may disregard the requirements of this section related to evaporative emission standards that apply for these vehicles before model year 2019. Similarly, you may disregard the refueling emission standards of this section before model year 2019 for vehicles above 10,000 pounds GVWR. For model year 2019, you may exclude from the phase-in calculation any evaporative families with vehicles that have a Job 1 date on or before March 3, 2018 (see 40 CFR 85.2304 ). Any vehicles not subject to Tier 3 evaporative emission standards during this phase-in period must continue to comply with the evaporative emission standards in § 86.1816-08(d) ; such vehicles are subject to the useful life provisions in § 86.1805-12 relative to evaporative emission standards. Each vehicle counting toward the phase-in percentage under this paragraph (g)(5) must meet all the standards that apply throughout the useful life as specified in § 86.1805-17 .(h)Small-volume manufacturers. Small-volume manufacturers meeting the eligibility requirements in § 86.1838 may delay complying with the requirements in this section until model year 2022. If meeting the Tier 3 standards would cause severe economic hardship, such manufacturers may ask us to approve an extended compliance deadline under the provisions of 40 CFR 1068.250 , except that the solvency criterion does not apply and there is no maximum duration of the hardship relief. 79 FR 23718 , Apr. 28, 2014, as amended at 80 FR 9107 , Feb. 19, 2015; 81 FR 73984 , Oct. 25, 2016; 86 FR 34371 , June 29, 2021; 88 FR 4478 , Jan. 24, 2023 81 FR 73984 , 12/27/2016; 86 FR 34371 , 7/29/2021; 88 FR 4478 , 3/27/2023; 89 FR 28166 , 6/17/2024