How a Reduced Pressure (RP) assembly is tested. Using a calibrated differential-pressure (PSID) gauge, a certified tester verifies four things:
- Check Valve #1 — static pressure drop: the baseline differential across the first check. Minimum 5.0 psid.
- Relief valve — opening point: the differential at which the relief first opens. Minimum 2.0 psid.
- Check Valve #2 — tightness: must hold tight against backpressure (above 1.0 psid).
- Buffer (safety margin): Check #1 minus the relief opening must be at least 3.0 psid.
All readings and line pressure are recorded, the device is tagged, and the result is certified pass or fail.