Safety Valves and Rupture Disk Notes

Safety Valves and Rupture Disk Notes 1. Any safety valve, piping, valve, or appurtenance exposed to freezing temperatures shall be properly positioned against collecting moisture and properly drained to prevent freeze-up. 2. Safety valves on Dowtherm and similar vaporizers shall be removed annually for cleaning and testing, at time of certificate inspection. Safety valves for compressed-air tanks shall not exceed three inches in diameter and shall be proportioned for the maximum number of cubic feet of free air that can be applied per minute. 3. Rupture disks or heads may be used as the pressure safety device on vessels containing non-toxic gases provided they are designed to fail at not more than the design pressure of the vessel.