What interval is specified for relief valve testing by hand lift and pressure lift?

• A. 2 years
• B. 5 years
• C. 12 years
• D. 20 years

Answer: (A)

Regular testing of relief valves is done to ensure they will open at the correct pressure and reseat properly, keeping systems safe from overpressure. The hand lift test checks that the valve can be manually actuated, confirming the spring tension and seating mechanism aren’t sticking and that the valve can be forced to lift without obstruction. The pressure lift test then applies actual system pressure until the valve pops open, verifying that it opens at the intended set pressure and that it clears the seat when lifting.

The interval of two years is chosen to balance safety with maintenance workload: it’s long enough to cover typical wear and drift in springs and seats but short enough to catch issues before they become dangerous in service. If a valve operates in more demanding conditions or experiences frequent cycling, more frequent testing might be needed. The longer intervals (five, twelve, or twenty years) would risk undetected drift or failure, which is why they aren’t used for routine relief valve verification.