OIML Recommendation R 139:2007 High Priority

Compressed gaseous fuel measuring systems for vehicles

Scope: This International Recommendation specifies the metrological and technical requirements applicable to compressed gaseous fuel measuring systems for vehicles, at type approval, initial verification and subsequent verifications. It also provides requirements for the approval of constituent elements of the measuring systems (meter, etc.). Measuring systems for liquid petroleum gas do not fall within the scope of this Recommendation, but within that of OIML R 117 as the fluid is in a liquid state.