416.2.5 Relief valve.
FGC § 416.2.5
Where a pressure relief valve is used to meet the requirements of Section 416, it shall have a flow capacity such that the pressure in the protected system is maintained at or below the limits specified in Section 416.2.1 under all of the following conditions: 1. The line pressure regulator for which the relief valve is providing overpressure protection has failed wide open.
2.The gas pressure at the inlet of the line pressure regulator for which the relief valve is providing overpressure protection is not less than the regulator's normal operating inlet pressure.
