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Which? Don't Buy smoke alarms

by Matt Stevens
A Don't Buy smoke alarm may fail to sound when there's smoke in the air - the consequences don't bear thinking about. Here are the alarms to avoid.

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

The smoke alarm video above shows the real-life implications of installing an unreliable smoke alarm. We reveal how our expert lab tests separate the smoke alarms you should avoid from those recommended as Best Buy smoke alarms.

You can unlock our list of Don't Buy smoke alarms on this page by signing up for a £1 Which? trial. Already a member? Log in now.

 Don't Buy smoke alarms

Our tough tests help us find the best and safest smoke alarms on the market, the ones that you can rely on to sound the alarm when there’s a fire and those that do this quickest. But the same tests also ensure we can alert you to the smoke alarms that fail to detect smoke – the one job they exist to do.

Compared to Best Buy smoke alarms, a Don’t Buy smoke alarm could take much, much longer to sound when smoke is in the air. We've also uncovered alarms that are so bad at detecting smoke in our tests, that in some fire scenarios they don't sound at all. In our latest tests, we found one alarm that failed to detect any smoke at all from two of our fires. 

By contrast, our Best Buy smoke alarms detected smoke quickly in all of our tests.

Best Buy vs Don't Buy smoke alarms

Log in now or sign up for a £1 Which? trial to unlock our full list of Don't Buy smoke alarms on this page.

Every time we test smoke alarms we use four different test fires to determine which are best at detecting smoke. We use fast flaming fires fuelled by plastics and solvents, as well as slower smouldering cotton and wood fires.

The models we name and shame as Don't Buys are proven to be the least effective at detecting smoke in our lab tests

  • In the Which? test lab, we put every smoke alarm through the same series of rigorous tests, including four types of house fire, sound output analysis, light visibility in smoke, and ease of use - so you'll know exactly what to expect.
  • We give every smoke alarm a Which? test score so you can immediately see which are the best and worst, plus how each model compares to each other in features and specifications.
  • Our tests cover a range of brands, prices and features; including smoke alarms with lights, hush buttons, 10-year batteries, smart alarms that link to your phone and those that link wirelessly.

A smoke alarm's manufacturer or price won't tell you whether it will fail to make the grade. We've tested smoke alarms from leading brands that have done badly enough in our tests for us to label them Don't Buys. We've also tested expensive and seemingly interesting and innovative alarms which proved to be a worrying let down when we tested them at our lab.

Find out which smoke alarms are Don't Buys and which are Best Buys by taking out a £1 Which? trial.

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