The provisions of this document apply to Single-Stage and economised refrigerant compressors of the positive displacement type. Selected test methods are described for the determination of the refrigerating capacity, the power, the isentropic efficiency and the coefficient of performance. These test methods provide results of sufficient accuracy to permit consideration of the suitability of a refrigerant compressor to operate satisfactorily under any set of basic test conditions required for a given refrigeration installation. Attention is drawn in particular to a number of special precautions necessary to reduce testing losses to a minimum. This document applies only to tests carried out at the manufacturer’s works, or wherever the necessary equipment for testing to the accuracy required can be made available. The accuracy of measurement are specified in Clause 4. NOTE - Tests on complete refrigeration installations are dealt with in ISO 916. Annexes B and C, which provide additional information, do not form integral parts of this document.