40 CFR § 79.2 - Definitions.
As used in this part, all terms not defined herein shall have the meaning given them in the Act:
(b) Administrator means the Administrator of the Environmental Protection Agency.
(c) Fuel means any material which is capable of releasing energy or power by combustion or other chemical or physical reaction.
(d) Fuel manufacturer means any person who, for sale or introduction into commerce, produces, manufactures, or imports a fuel or causes or directs the alteration of the chemical composition of a bulk fuel, or the mixture of chemical compounds in a bulk fuel, by adding to it an additive, except:
(1) A party (other than a fuel refiner or importer) who adds a quantity of additive(s) amounting to less than 1.0 percent by volume of the resultant additive(s)/fuel mixture is not thereby considered a fuel manufacturer.
(e) Additive means any substance, other than one composed solely of carbon and/or hydrogen, that is intentionally added to a fuel named in the designation (including any added to a motor vehicle's fuel system) and that is not intentionally removed prior to sale or use.
(i) Chemical structure means the molecular structure of a compound in an additive.