When should you replace a smoke alarm?

changing smoke alarm battery

Alice Piper

Posted April 01, 2022

Smoke alarms save lives. Check that your smoke alarms are all working effectively this weekend for peace of mind.

The Country Fire Authority (CFA) is urging all Victorians to check their smoke alarms when they turn back their clocks this weekend for the end of daylight saving.

Over time, smoke alarms may not operate effectively due to dust build up, insects, airborne contaminants and electrical corrosion. Checking smoke alarms involves pressing the 'test' button to ensure it's in working order, and cleaning it with a duster, vacuum cleaner or gentle wipe.

CFA Chief Officer Jason Heffernan says smoke alarm checks are vital to saving lives should a fire occur in the home. 

“If there is a fire in your home, a working smoke alarm can allow you to evacuate early and survive.”

“We know that many fatal fires start at night and the smell of smoke won’t wake you up – so ensuring your smoke alarms are working is crucial to protecting you and your family,” adds Heffernan. 

When must a smoke alarm be replaced?

The CFA recommends that all smoke alarms in the home be powered by a 10-year lithium battery and be interconnected. This means that should one smoke alarm be activated, the other smoke alarms in the house will also activate, alerting household members in different parts of the home that there could be danger. 

Heading into winter when heaters, fireplaces, and electric blankets will be used more frequently, there is an elevated risk of house fires, something Fire Rescue Commissions Ken Block says is a real concern if smoke alarms aren't working properly. 


Hands installing fire alarm

It takes just a few minutes to clean and test a smoke alarm to ensure it's in working order. Image: Getty

“There’s no point having a smoke alarm installed if it isn’t working – a smoke alarm that is properly maintained can save your life if there is a fire."

“It will only take a few minutes to clean and then test your smoke alarm by pushing the test button. It’s a small step you can take to ensure your smoke alarms will work when you need it most,” he adds. 
“Regardless of the type of smoke alarm you have, all smoke alarms should be replaced every 10 years,” Commissioner Block said.

Guide to installing, maintaining and checking smoke alarms

Install smoke alarms in every room 

Ensure that every bedroom and living area is fitted with a smoke alarm, and that all alarms are interconnected. if you're unsure, leave it to qualified professionals to supply and install smoke alarms in your home.

Regularly clean all smoke alarms

Use a duster, vacuum cleaner or gentle wipe to ensure all smoke alarms are free of dust build up, insects, or any other substance that can prevent them from working. 


Qualified professional changing smoke alarm in a home

Consult a professional if you're unable to install or change a smoke alarm yourself. Image: Supplied.

Be alert to smoke alarm faults and age

If your smoke alarm is turning a yellow colour, it is a sign the unit is ageing and needs replacing. The same applies for smoke alarms that continually make a ‘chirp’ sound, as this is a sign the battery has stopped working and the unit needs replacing. 
Finally, if your smoke alarm keeps activating for no reason, it is time to replace the unit. As smoke alarms age, they become particularly sensitive to dust particles in the air, so as well as regularly cleaning smoke alarms, be mindful of their age as well.  

Test the smoke alarm battery

The CFA recommends testing the battery each month by pressing and holding the smoke alarm's test button until it beeps three times. If there are no solid beeps, or the smoke alarm sounds laboured when testing, it can be a sign the battery needs changing. 

Leave it to qualified professionals if you’re not comfortable changing a smoke alarm battery yourself, or working at height on a ladder.

Replace the smoke alarm or battery

All smoke alarm units need replacing every 10 years with the most advanced model available, which is currently a hard wired, interconnected smoke alarm. 

If you have a 9-volt battery in your smoke alarm, the battery needs replacing every year. 


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