This standard applies to diaphragm gas meters, that are gas volume meters in which the gas flow is measured by means of measuring chambers with deformable walls, including gas meters with a built-in temperature conversion device. With regard to the gas volume meters defined above, this standard complements GSO standard to be approved (1) “General provisions for gas volume meters” the provisions of which apply jointly with the following requirements. NOTE: In this standard, diaphragm gas meters are designated “gas meters” or “meters”.