Knowledge article
Fire Alarm Periodic Servicing
BS 5839 recommends a competent person services a fire alarm system at least every six months, testing detectors, sounders, panel, batteries and interfaces.
Beyond the weekly user test, BS 5839 recommends periodic servicing by a competent person at least every six months. This is the thorough, professional inspection that keeps the whole system reliable.
What servicing covers
Over the service visits, a competent engineer will:
- Test a sample of detectors for correct response (working through all detectors across visits);
- check sounders and any visual alarm devices;
- verify the control panel, indications and fault monitoring;
- test standby batteries and power supplies; and
- confirm interfaces to other systems (door releases, plant shutdown, monitoring) operate correctly.
Frequency
Six-monthly is the baseline. Larger or higher-risk systems, or those with a history of faults, may be serviced more often as set by the risk assessment and designer.
Records and follow-up
The engineer records the service, notes any defects, and issues a report. Defects should be remedied promptly and logged in the fire logbook. Servicing complements the on-site weekly user tests — together they form the maintenance regime BS 5839 expects.
Frequently asked questions
How often should a fire alarm be professionally serviced?
BS 5839 recommends servicing by a competent person at least every six months. Larger or higher-risk systems, and those with a history of faults, may be serviced more frequently as determined by the risk assessment and system designer.
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Learn moreThis article provides general guidance and distinguishes legislation, British Standards and good practice. It is not legal advice. Always confirm the specific duties applying to your property and tenure.