Gaseous fuel
Gaseous fuel includes, but is not limited to, natural gas, process gas, landfill gas, coal derived gas, refinery gas, and biogas. Blast furnace gas and process gases that are regulated under another subpart of this part, or part 60, part 61, or part 65 of this chapter, are exempted from this definition.
Source
40 CFR § 63.7575
Scoping language
Terms used in this subpart are defined in the Clean Air Act, in 63.2 (the General Provisions), and in this section as follows: