40 CFR § 85.501
General applicability
June 9, 2020
(a) This subpart describes the provisions related to an exemption from the tampering prohibition in Clean Air Act section 203(a) (42 U.S.C. 7522(a)) for light-duty vehicles, light-duty trucks, medium-duty passenger vehicles, heavy-duty vehicles, and heavy-duty engines. This subpart F does not apply for highway motorcycles or for nonroad or stationary engines or equipment.
(b) For purposes of this subpart, the term “you” generally means a clean alternative fuel conversion manufacturer, which may also be called “conversion manufacturer” or “converter”.