How often should you test smoke alarms? A UK guide for homeowners and landlords

Test your smoke alarms at least once a month by pressing the test button. That is the UK government's Fire Kills advice for every type of smoke alarm, and the British Standard for home fire alarms agrees for most systems. Landlords in England must also check each alarm works on the day a new tenancy begins. Replace alarms about every ten years. Ajax FireProtect 2 alarms on a hub also check themselves and log each test.

How often should you test smoke alarms in the UK?

The Fire Kills campaign says to test smoke alarms at least monthly, whatever kind you have, and that you are around 11 times more likely to die in a fire with no working smoke alarm.

BS 5839-6, the British Standard for fire alarms in homes, points the same way. Scottish Government guidance sums it up as weekly tests for Grade A systems (those with a fire alarm control panel) and at least monthly for the rest, with weekly testing where possible.

What do landlords have to do by law?

In England, regulation 4 of the Smoke and Carbon Monoxide Alarm (England) Regulations 2015, as amended, requires:

• a smoke alarm on each storey with a room used as living accommodation;
• a carbon monoxide alarm in any such room with a fixed combustion appliance, such as a boiler (gas cookers are excluded);
• a check that each alarm works on the day a new tenancy begins;
• repair or replacement of an alarm a tenant reports as faulty, as soon as reasonably practicable.

The GOV.UK guidance sets no testing interval during a tenancy, but suggests showing tenants how to test, and says keeping a record of tests is the landlord's responsibility. Councils enforce the rules and can fine a landlord who ignores a remedial notice up to £5,000. HMO managers must also keep fire alarms in good working order under the Management of Houses in Multiple Occupation (England) Regulations 2006.

Wales: regulation 5 of the Renting Homes (Fitness for Human Habitation) (Wales) Regulations 2022 requires a mains-powered smoke alarm on each storey, linked to the other mains alarms and kept in proper working order, plus a CO alarm in any room with a gas, oil or solid fuel appliance.

Scotland: the Scottish Government says every home, owner-occupied included, needs interlinked smoke alarms in the living room and every hallway and landing and a heat alarm in the kitchen, plus a CO alarm in any room with a carbon-fuelled appliance.

The electrical safety check that GOV.UK says rented homes in England need at least every five years covers the electrics, not the fire alarms. This is a summary, not legal advice; your council can confirm what applies.

How do you test a smoke alarm properly?

1. Press and hold the test button until the alarm sounds.
2. If it stays silent, fit a new battery or, failing that, replace the alarm.
3. A regular chirp means a low battery: Fire Kills says replace the battery straight away, and never take batteries out after a false alarm unless you are replacing them.
4. Landlords: note the date, the alarm and the result.

How does an Ajax FireProtect 2 alarm test itself?

An Ajax wireless fire alarm from the FireProtect 2 range starts a self-test in two ways: hold the centre of the front panel (the Test/Mute button) for about 1.5 seconds, or choose Self-test in the detector's settings in the Ajax app. Ajax says the test starts within 30 seconds, the siren and LEDs show each step, and the app shows the result. If the alarm gives no sound or light, Ajax says it must not be used.

On a hub, the system watches every detector for faults, low battery and end of life all the time. Ajax says hub-connected alarms generally need no routine testing, but still encourages monthly tests so people know the sound.

Without a hub, each alarm still sounds its own 85 dB siren but sends nothing to the app. For alerts and test results, Ajax lists the Ajax Hub 2 (2G) control panel and the Hub (4G) Jeweller as compatible on current firmware.

Can a landlord check alarms without a visit?

Partly. On a hub, Ajax describes:

• self-tests started from the app, or by an engineer in the Ajax PRO app;
• results kept in the event log, visible to the owner, a service company and any monitoring station;
• an automatic maintenance report after testing.

The England regulations do not say how the day-one check must be done, so a dated event-log result can help, though the council decides what evidence it accepts. A remote test still sounds the alarm in the property, so warn tenants first.

When should smoke alarms be replaced?

Fire Kills says replacing alarms every ten years is generally a good idea, sealed ten-year alarms are replaced at ten years, and some need replacing sooner.

• Ajax gives FireProtect 2, CO sensors included, a 10-year life.
• The FireProtect 2 SB (Heat/Smoke) sealed-battery alarm runs for up to 10 years; then you replace the whole alarm.
• The FireProtect 2 RB with replaceable batteries takes two CR123A cells.
• Ajax says a detector keeps working for about a month after its low-battery alert.

Which Ajax fire alarm suits which job?

For kitchens, Fire Kills suggests a heat alarm such as the FireProtect 2 SB (Heat) kitchen heat alarm. The mains-powered FireProtect 2 AC (Heat/Smoke) and the FireProtect 2 AC (Heat/Smoke/CO) combined alarm need a qualified electrician to fit them; in Wales, ask them to confirm the layout meets regulation 5. Prices include VAT, delivery is extra, and prices can change. See our Ajax hubs and wireless alarm range, everything we stock from Ajax and our wider fire alarm range.

Our take

A monthly press of the test button costs nothing, and we would keep to it whatever alarm you fit. Ajax's self-checks and event log do not replace that habit, but for landlords they add a dated record and an alert when an alarm fails between visits. Zenith Security Co. has supplied security equipment since 2012; we supply Ajax fire alarms rather than fit them, and we can recommend a qualified installer depending on the job and area.

Need a list for a property? Call 01902 902251, contact us online, or open a trade account if you buy for several properties. We ship nationally to England, Scotland and Wales.

Testing smoke alarms: quick questions

How often should landlords test smoke alarms?
In England, check on the day each new tenancy begins and repair faults tenants report. Fire Kills advises at least monthly tests in every home.

Do heat and CO alarms need testing too?
Yes. BS 5839-6 covers heat alarms as well as smoke alarms; test CO alarms as the maker says. FireProtect 2 CO versions use the same front button.

Can I test my Ajax alarm from my phone?
Yes, if it is on a hub: run Self-test from the detector's settings in the Ajax app. It sounds where fitted and the app shows the result.

Do the same rules apply to a shop or office?
No. In England and Wales, workplaces fall under the Regulatory Reform (Fire Safety) Order 2005, and GOV.UK says regular checks must confirm fire alarms work, with faults recorded.

Source: Ajax Systems blog, 13 December 2024 and 8 April 2026, with Fire Kills, GOV.UK (electrics, workplaces), legislation.gov.uk (England, HMOs, Wales) and the Scottish Government (BS 5839-6 summary). Device figures are Ajax's own.