API 570 (2024) introduced new, formalized clauses specifically addressing the As-Received Condition, Testing, and Actions for relief valves. When a Pressure Relief Device (PRD) is pulled for its scheduled interval, the shop must now strictly document its “as-received” condition and perform an initial POP test before any cleaning, disassembly, or maintenance occurs.
If a valve is stuck shut or pops at 150% of its set pressure due to process fouling, that is a critical mechanical integrity failure. Previously, some repair shops would clean a valve before testing it, which masked in-service failures and compromised the historical reliability data used to justify inspection intervals. If the as-received POP test fails (e.g., opens too early due to weakened springs, or fails to open due to fouling), the failure must be recorded, the valve must be fully dismantled for a root-cause inspection, and the testing interval for that PRD must be re-evaluated and likely shortened.