What are the typical inspection/testing requirements of the safety circuit (rupture disks / relief devices)?

An annual inspection of safety devices is recommended. Testing requirements will be based on the type of device and a quantified risk analysis. Typical replacement or function testing of relief valves is between 5 and 10 years depending on the application within the industrial gas industry. Rupture discs are not tested but are frequently replaced on an interval based on manufacturer recommendations and a mechanical integrity program established by the operator. For transportation applications, rupture discs are usually replaced at vessel requalification at either 5 or 10 years depending on test method.