How long will my smoke alarms last?

Question

Do smoke alarms and carbon monoxide alarms last forever? When should I replace them?

Answer

It is recommended that you replace any smoke alarm and carbon monoxide alarm after being in use for 10 years.

As electronic devices, smoke detectors are subject to random failures. In 10 years there is roughly a 30% probability of failure before replacement. After 15 years, the chances are better than 50:50 that your alarm will fail. That is too big of a risk to take.

If your smoke alarm was manufactured in 2011 or before, it must be replaced!

Replacing alarms after 10 years protects against the chance of failure, but monthly testing is still your best means of making sure your alarm will work.

Regular testing of your smoke alarm is vital. To help you never forget, you can subscribe for regular reminders with helpful advice.
In addition, if your smoke alarm is the ionisation type, we strongly recommend it is replaced immediately, no matter how old it is.