Inspection, Testing, and Maintenance
Domain 4 is NFPA 25 territory: who is responsible, what is inspected and how often, how tests are performed, and what a deficiency obliges you to do. The exam favours frequency questions and procedure questions - what you record, in what order, and what triggers follow-up.
Responsibility and records
The property owner is responsible for ITM; the contractor typically performs it and provides reports. Records must be maintained and made available to the authority having jurisdiction. Frequencies are maximum intervals, and an impairment does not pause them.
Frequencies worth memorising
Gauges on wet systems are inspected quarterly, and more often on dry systems. Control valves are checked for open position on a short cycle, with monthly permitted where the valve is electrically supervised and locked or sealed. The main drain test is annual and also after any shutdown or impairment. Waterflow alarm devices are tested quarterly. Dry-pipe valve trip tests are annual, and internal pipe inspection is required at multi-year intervals, with dry systems on a five-year cycle.
How the main drain test works
Record the static pressure, open the main drain fully, let the flow stabilise, record the residual pressure, then close slowly to avoid water hammer. The value of the test is the comparison with the baseline, not the absolute numbers.
Worked example
Baseline main drain test at commissioning: static 72 psi, residual 62 psi. Today: static 78 psi, residual 48 psi. Step 1: the residual drop is 62 − 48 = 14 psi. Step 2: as a percentage, 14 ÷ 62 = 22.6 percent. Step 3: a drop of roughly 10 percent or more from the baseline points to a partially closed valve, an obstruction, or a supply change, so an investigation is required before the system is considered reliable - not a note for next year's test.
Traps that cost marks
Reporting a deficiency without escalating an impairment; slamming the main drain shut; confusing the annual main drain test with the quarterly alarm test; forgetting to drain low points after a dry-pipe trip test; and recording only the residual pressure, which makes comparison impossible.