Equipment
Equipment means one of the following things:
(1) Any vehicle, vessel, or other type of equipment that is subject to the requirements of this part or that uses an engine that is subject to the requirements of this part. An installed engine is part of the equipment. Motor vehicle trailers are a type of equipment that is subject to the requirements of this part.
(2) Fuel-system components that are subject to an equipment-based standard under this chapter. Installed fuel-system components are also considered part of the engine/equipment to which they are attached.
Source
40 CFR § 1068.30
Scoping language
The following definitions apply to this part. The definitions apply to all subparts unless we note otherwise. All undefined terms have the meaning the Clean Air Act gives to them. The definitions follow: