(a) Exhaust emissions. You must show that your engines meet the following exhaust emission standards, except as specified in paragraphs (b) through (d) of this section:

(b) Evaporative emissions. Except as specified in § 1054.20, new equipment using engines that run on a volatile liquid fuel (such as gasoline) must meet the evaporative emission requirements of 40 CFR part 1060. The requirements of 40 CFR part 1060 that apply are considered also to be requirements of this part 1054. Marine vessels using auxiliary marine engines subject to this part must meet the evaporative emission requirements in 40 CFR 1045.112 instead of the evaporative emission requirements in this part. We specify evaporative emission requirements for handheld and nonhandheld equipment separately in §§ 1054.110 and 1054.112.

(c) Wintertime engines. Emission standards regulating HC and NO_X exhaust emissions are optional for wintertime engines. However, if you certify an emission family to such standards, those engines are subject to all the requirements of this part as if these optional standards were mandatory.

(d) Two-stroke snowthrower engines. Two-stroke snowthrower engines may meet exhaust emission standards that apply to handheld engines with the same engine displacement instead of the nonhandheld standards that would otherwise apply.

(e) Relationship between handheld and nonhandheld engines. Any engines certified to the nonhandheld emission standards in § 1054.105 may be used in either handheld or nonhandheld equipment. Engines above 80 cc certified to the handheld emission standards in § 1054.103 may not be used in nonhandheld equipment. 40 CFR 1068.101 prohibits the introduction into commerce or importation of such nonhandheld equipment except as specified in this paragraph (e). For purposes of the requirements of this part, engines at or below 80 cc are considered handheld engines, but may be installed in either handheld or nonhandheld equipment. These engines are subject to handheld exhaust emission standards; the equipment in which they are installed are subject to handheld evaporative emission standards starting with the model years specified in this part 1054. See § 1054.701(c) for special provisions related to emission credits for engine families with displacement at or below 80 cc where those engines are installed in nonhandheld equipment.

(f) Interim provisions. It is important that you read § 1054.145 to determine if there are other interim requirements or interim compliance provisions that apply for a limited time.