Periodic pressure test of the cylinder shell on an interval set by NFPA 10
Used across 3 Anvilfield field guides, most in HVAC.
Also defined as
Datacenter: A pressure test using water (or another liquid), the safe default because water stores little energy and a failure does not let go violently
Plumbing: A pressure test using water, the safe default because water stores almost no energy and a failure weeps instead of bursting