Defines the requirements and tests for the construction, performance, safety and production of class 1,5 diaphragm gas meters (referred to as meters) having co-axial single pipe, or two pipe connections, used to measure volumes of fuel gases of the 1st, 2nd and 3rd families in accordance with EN 437:2003+A1:2009, at maximum working pressures not exceeding 0,5 bar and maximum actual flow rates not exceeding 160 m[3]/h over a minimum ambient and gas temperature range of -10 degree C to +40 degree C.