Fire alarm testing is two separate jobs that get talked about as one. There is the short routine test somebody on site does every week, and there is the periodic service and inspection a competent engineer does a few times a year. The law names the duty rather than the interval, and the interval comes from the British Standard the system was designed to, which is why a landlord and a factory can both be compliant on very different schedules.
What the law actually requires
In England and Wales the Regulatory Reform (Fire Safety) Order 2005 makes the responsible person keep fire safety equipment in efficient working order and in good repair, and requires the premises to be equipped with appropriate fire detectors and alarms where the risk assessment shows they are needed. Neither article prints a testing interval. That is deliberate: a building with sleeping occupants and one with a single open workshop do not need the same regime, and the Order asks for a regime that suits the risk you assessed.
Where the intervals come from
The intervals people quote come from BS 5839-1 for non-domestic systems and BS 5839-6 for dwellings. Those standards recommend a short user test each week, rotating the call point used so every device is proved over time, and a periodic inspection and servicing visit by a competent person during the year. The standards are published by BSI and are not free to read, so a contractor who tells you the interval should be able to tell you which clause of which part they are working to.
Who may do which test
The weekly test is a user task. Somebody on site operates one call point with the test key, confirms the sounders work everywhere they are meant to be heard, resets the panel and writes it down. The periodic service is not a user task: it involves every detector, the standby supply, the cause and effect programming and any connection to a monitoring centre. Third party certification schemes exist precisely so a duty holder can check the firm before letting them near the panel.
What a good record looks like
Whoever inspects your building after an incident will read the log book, not your memory. A useful entry names the date, the device tested, who tested it, whether the sounders were audible in the places that matter, and what was done about anything that failed. A run of ticks with no faults ever recorded is a warning sign rather than a good sign, because real systems develop faults and a book that never records one is a book nobody is filling in.
Questions people ask about fire alarm testing
Is weekly fire alarm testing a legal requirement?
The Fire Safety Order requires the system to be maintained in efficient working order; it does not name a weekly interval. The weekly user test is the recommendation in BS 5839-1, and it is the regime most risk assessments adopt because it is the one inspectors expect to see recorded.
Do I have to warn people before testing the alarm?
Yes, if you do not want the building evacuated. A test at a fixed, advertised time is normal practice. If the test is unannounced, people are entitled to treat it as a real alarm and leave, which is a good reason to keep the announced slot consistent.
What happens if a weekly test is missed?
Record the gap and the reason rather than backfilling the book. A missing week that is explained reads as a system somebody manages; an unexplained gap, or an entry written later, is what turns a routine inspection into a difficult conversation.