This International Standard specifies the requirements for the safety of persons and property, provides guidance for the protection of the environment, and establishes procedures for the operation, maintenance, and repair of refrigerating systems and the recovery of refrigerants.This part of ISO 5149 specifies the classification and selection criteria applicable to the refrigerating systems and heat pumps. These classification and selection criteria are used in ISO 5149-2, ISO 5149-3, and ISO 5149-4.This part of ISO 5149 applies to:a) refrigerating systems, stationary or mobile, of all sizes including heat pumps;b) secondary cooling or heating systems;c) the location of the refrigerating systems;d) replaced parts and added components after adoption of this part of ISO 5149 if they are not identical in function and in the capacity.This part of ISO 5149 applies to fixed or mobile systems, except to vehicle air conditioning systems covered by a specific product standard, e.g. ISO 13043 and SAE J 639.This part of ISO 5149 is applicable to new refrigerating systems, extensions or modifications of already existing systems, and for used systems, being transferred to and operated on another site.This part of ISO 5149 also applies in the case of the conversion of a system to another refrigerant.Annex A specifies the limits for the quantity of refrigerant charge permitted in systems in various locations and occupancy classes.Annex B specifies the criteria for safety and environmental considerations of different refrigerants used in refrigeration and air conditioning.Systems containing refrigerants which are not listed in ISO 817 are not covered in this part of ISO 5149.

Originated in Australia as part of AS CB3—1933.Final Australian edition AS 1677—1986.Originated in New Zealand as NZSS 1653:1962.Final New Zealand editions NZS 5235.1:1991 and NZS 5235.2:1988.AS 1677—1986, NZS 5235.1:1991 and NZS 5235.2:1998 jointly revised, amalgamated and redesignated in part as AS/NZS 1677.2:1998.Revised and redesignated in part as AS/NZS 5149.1:2016. Originated in Australia as part of AS CB3-1933. Final Australian edition AS 1677-1986. Originated in New Zealand as NZSS 1653:1962. Final New Zealand editions NZS 5235.1:1991 and NZS 5235.2:1988. AS 1677-1986, NZS 5235.1:1991 and NZS 5235.2:1998 jointly revised, amalgamated and redesignated in part as AS/NZS 1677.2:1998. Revised and redesignated in part as AS/NZS 5149.1:2016. Reissued incorporating Amendment No. 1 (March 2018). Reissued incorporating Amendment No. 2 (July 2018).