This Gas Industry Standard (GIS) specifies the requirements for plastics bodied polyethylene valves of sizes up to and including 180 mm for use at operating pressures not exceeding 5.5 bar and operating temperatures in the range -20 °C to 40 °C, capable of connection to the polyethylene pipe system by electrofusion jointing over a temperature range of -5 °C to 30 °C. It is applicable to valves that are to be buried.