This standard specifies the safety, constructional and performance requirements for pressure governors, hereafter referred to as governors, intended for use with gas appliances. It also gives the test procedures for evaluating these requirements and information necessary for the purchaser and user. This standard applies to pressure governors for gas-burning appliances of nominal connection size up to and including DN 50 and that may be used and tested independently of thes appliances. Thes governors are suitable for one or more of the fuel gases of the 1sts, 2nd and 3rd families (see Annex A), at inlet pressure up to and including 200 mbar. This standard does not cover: a) governors connected directly to main pipeworks or to a container that maintains a standard distribution pressure; b) governors intended for gas appliances to be installed out-of-doors and exposed to the environment.