This European 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.The term “refrigerating system” used in this European Standard includes heat pumps.This part of EN 378 specifies the classification and selection criteria applicable to refrigerating systems. These classification and selection criteria are used in parts 2, 3 and 4.This standard applies:a)to refrigerating systems, stationary or mobile, of all sizes except to vehicle air conditioning systems covered by a specific product standard e.g. ISO 13043;b)to secondary cooling or heating systems;c)to the location of the refrigerating systems;d)to replaced parts and added components after adoption of this standard if they are not identical in function and in the capacity;Systems using refrigerants other than those listed in Annex E of this European Standard are not covered by this standard.Annex C specifies how to determine the amount of refrigerant permitted in a given space, which when exceeded, requires additional protective measures to reduce the risk.Annex E specifies criteria for safety and environmental considerations of different refrigerants used in refrigeration and air conditioning.This standard is not applicable to refrigerating systems and heat pumps which were manufactured before the date of its publication as a European Standard except for extensions and modifications to the system which were implemented after publication.This standard is applicable to new refrigerating systems, extensions or modifications of already existing systems, and for existing stationary systems, being transferred to and operated on another site.This standard also applies in the case of the conversion of a system to another refrigerant type, in which case conformity to the relevant clauses of parts 1 to 4 of the standard shall be assessed.Product family standards dealing with the safety of refrigerating systems takes precedence over horizontal and generic standards covering the same subject.