§ 86.099-10 Emission standards for 1999 and later model year Otto-cycle heavy-duty engines and vehicles.

Section 86.099-10 includes text that specifies requirements that differ from § 86.098-10. Where a paragraph in § 86.98-10 is identical and applicable to § 86.099-10, this may be indicated by specifying the corresponding paragraph and the statement “[Reserved]. For guidance see § 86.098-10.”

(a) [Reserved]. For guidance see § 86.098-10.

(b) Evaporative emissions from heavy-duty vehicles shall not exceed the following standards. The standards apply equally to certification and in-use vehicles. The spitback standard also applies to newly assembled vehicles. For certification vehicles only, manufacturers may conduct testing to quantify a level of nonfuel background emissions for an individual test vehicle. Such a demonstration must include a description of the source(s) of emissions and an estimated decay rate. The demonstrated level of nonfuel background emissions may be subtracted from emission test results from certification vehicles if approved in advance by the Administrator.