Inspection, Testing, and Maintenance
Frequency logic
NFPA 72 Chapter 14 sets inspection, testing, and maintenance (ITM) frequencies. The default rhythm most exam questions rely on: annual testing of initiating devices, notification appliances, the control panel, and most other system components; annual functional testing of duct detectors and waterflow/valve tamper devices; and annual battery inspection with periodic load testing. Smoke detector sensitivity must be verified within one year of installation and at defined intervals afterward - commonly every alternate year under the standard, though the manufacturer's published instructions or a specific code edition may require annual. Where a documented performance-based test program is approved, extended intervals may apply, but the burden of proof is on the written program.
The process
ITM means more than pushing a test button. It includes a written test plan, recording results device-by-device, documenting deficiencies, notifying the owner in writing, and following impairment procedures (notification of the AHJ and fire department, fire watch, or system shutdown scheduling). Records of inspection and testing must be retained - at minimum until the next test and for a period set by the code and AHJ, commonly one year - and made available on request.
Worked example
An annual test of a 400-device addressable system. Devices are tested from the SLC in groups, each device's address is confirmed at the panel, its response is observed at the correct zone/annunciator, and notification appliances are verified for audibility and synchronization in each area. Duct detectors are tested with listed aerosol or manufacturer method, not by tapping. Results go on a device-by-device report; any failure is written up as a deficiency with a corrective action date.
Traps
Assuming "annual" covers everything (some items are quarterly, some semiannual, some performance-based); testing only the devices that were serviced; failing to document deficiencies and owner notification; skipping notification appliance testing because the horns "obviously work."