ISO 6743-3:2003 establishes the detailed classification of lubricants for use in family D, air compressors, gas compressors and refrigeration compressors.

The intention of ISO 6743-3:2003 is to provide a rationalized range of the most commonly used internationally available lubricants for air, gas and refrigeration compressors, without resorting to unnecessary restriction by specifications or products description.

The primary intention of this classification is to describe and promote the use of the type of lubricant which is best suited for the particular application, specifically with stationary air compressors, with the aim of reducing as far as possible the risks of fire and explosion. Relevant safety rules are given in ISO 5388.

ISO 6743-3:2003 should be read in conjunction with ISO 6743-99.