primary reference fuel


primary reference fuel

[′prī‚mer·ē ′ref·rəns ‚fyül] (materials) Gasoline; isooctane, n-heptane, or mixtures thereof used in the American Society for Testing and Materials-Cooperative Fuel Research gasoline test engine to determine the octane rating of commercial gasoline. Diesel fuel; cetane, α-methylnaphthalene, or mixtures thereof used in ASTM-CFR diesel test engines to rate the cetane number of commercial diesel fuels.