GIS/V4: Specification for service isolation valves up to 50 mm diameter for use up to 7 bar maximum working pressures
This Gas Industry Standard specifies the requirements for the materials, design, testing, labelling and packaging of non-lubricated service isolation valves, of the spherical plug type, suitable for operation at pressures up to 2 bar and in the temperature range –15 °C to +50 °C. This standard applies to valves capable of operation by means of a special key that is not permanently attached to the body of the valve.