Engine/equipment and engines/equipment mean engine and/or equipment depending on the context. Specifically these terms mean the following:
(1) Engine(s) when only engine-based standards apply.
(2) Engine(s) for testing issues when engine-based testing applies.
(3) Engine(s) and equipment when both engine-based and equipment-based standards apply.
(4) Equipment when only equipment-based standards apply.
(5) Equipment for testing issues when equipment-based testing applies.
40 CFR § 1068.30
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: