SAE J 2973:2018-12-19

This SAE recommended practice specifies a standard geometry leak channel to set the leak threshold and compare results from a variety of leak test technologies and test conditions. This practice applies to fuel system assemblies and components which have a risk of allowing regulated fuel or fuel vapors to continuously escape to atmosphere. A component or assembly tested to this standard has a zero HC leakage threshold because the selected leak channel (Equivalent Channel) will self-plug and will not emit measurable hydrocarbon liquid or vapors. Therefore this standard eliminates leaks as a source of evaporative emission. This practice was primarily developed for pressurized and non-pressurized fuel systems and components containing liquid hydrocarbon based fuels.