This standard applies to the methods of testing for rating the thermodynamic performance of positive displacement refrigerant compressors and compressor units that are operated at discharge pressures greater than the critical pressure of the refrigerant which either (a) do not have intermediate cooling or refrigerant injection or (b) incorporate intermediate cooling means or refrigerant injection that is achieved by compressor power and controlled by a steady-flow-rate method. PURPOSE The purpose of this standard is to provide methods of test for rating the thermodynamic performance of positive displacement refrigerant compressors and compressor units that operate at supercritical pressures of the refrigerant.