Inspection, Testing, and Maintenance of Sprinkler Systems
NFPA 25 baseline
NFPA 25 is the inspection, testing, and maintenance standard; it is not a design standard. Michigan's adopted fire code references it, so the owner-not the installing contractor-is ultimately responsible for compliance. The contractor often performs the work under contract, but the owner must keep records.
Frequencies and tasks
- Weekly: control valves confirmed open and supervised.
- Monthly: gauges read and recorded.
- Quarterly: waterflow alarm devices and supervisory signal devices tested.
- Annually: main drain test, flow test, dry-pipe valve trip test, antifreeze concentration, and valve inspection.
- Every 5 years: internal pipe inspection and gauge calibration or replacement per NFPA 25.
- Sprinkler spare heads and wrench kept in the cabinet; replacement heads matched to the original.
Worked example
A wet-pipe office system shows 65 psi static on the gauge during the annual main drain test, compared with 72 psi on the baseline record. The residual drop is larger than the baseline. The technician should not simply record the number: investigate for a partially closed valve, an obstructed main drain, or a supply change, then re-test and document the correction. If the supply itself has degraded, the owner may need a hydraulic evaluation, not just a new gauge.
Traps
Treating a monthly gauge reading as a full inspection; skipping the main drain because the system "looks fine"; testing alarms without notifying the monitoring company; replacing sprinklers with a different temperature rating or K-factor without review; and failing to document deficiencies and corrections.
Records
Keep inspection tags, test reports, and repair records on site. The exam rewards knowing who is responsible and what evidence proves the work was done.