§ 86.1813-17 Evaporative and refueling emission standards.

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]

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