Chemicals added to fuel in very small quantities to improve and maintain fuel quality.  Detergents, corrosion inhibitors and lubricants are examples of fuel additives.

Broad term that applies to any change after the original purchase, such as adding equipment. When applied to AFVs, it refers to conversion devices or kits for conventional fuel vehicles.

Toxic air pollutants defined under Title II of the CAA, including benzene, formaldehyde, acetaldehyde, 1-3 butadiene, and polycyclic organic matter (POM). Benzene is a constituent of motor vehicle exhaust, evaporative, and fueling emissions. The other compounds are exhaust pollutants.

Methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; non-alcohol fuels (such as biodiesel) derived from biological material; and electricity. 'P-Series' fuels were added to this list since the original definition in EPAct.

A fuel provider (or any affiliate or business unit under its control) is an alternative fuel provider if its principal business is producing, storing, refining, processing, transporting, distributing, importing, or selling (at wholesale or retail) any alternative fuel (other than electricity); or generating, transmitting, importing, or selling (at wholesale and retail) electricity; or if that fuel provider produces, imports, or produces and imports (in combination), an average of 50,000 barrels per day of petroleum and 30% (a substantial portion) or more of its gross annual revenues are derived from producing alternative fuels.

As defined by the Energy Policy Act, any dedicated, flexible-fuel, or dual-fuel vehicle designed to operate on at least one alternative fuel.

A program sponsored by DOE and managed by the National Renewable Energy Laboratory to collect data and information on all types of Alternative Fuels and AFVs across the country.

A program managed by DOE with the goals of improving national energy security by displacing imported oil, improving air quality by development and widespread use of alternative fuels for transportation, and increasing the production of AFVs.

Public Law 100-494. Encourages the development, production and demonstration of alternative motor fuels and AFVs.

A nonprofit organization that provides a management system to develop published technical information. ASTM standards, test methods, specifications, and procedures are recognized as definitive guidelines for motor fuel quality as well as a broad range of other products and procedures.

Describes a compound that does not contain any water. Ethanol produced for fuel use is often referred to as anhydrous ethanol, as it has had almost all water removed.

Hydrocarbons based on the ringed six-carbon benzene series or related organic groups. Benzene, toluene and xylene are the principal aromatics, commonly referred to as the BTX group. They represent one of the heaviest fractions in gasoline.