When should you replace a smoke alarm?

changing smoke alarm battery


Posted September 25, 2023

Smoke alarms save lives. Check that your smoke alarms are all working effectively when changing your clocks for daylight saving time.

According to the Country Fire Authority (CFA), there are 3,000 house fires in Victoria each year – most of which could be prevented by taking the necessary safety precautions.

The CFA advises that linking the task of changing your clocks for daylight saving time (DST) with checking smoke alarms is the best way for all homeowners, landlords and renters to keep on top of this important safety home maintenance task.

Smoke alarms and fire safety guide

What are the greatest risks that cause house fires?

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

“Fire risk is greatest at night when you are asleep. When we sleep, we lose our sense of smell and the carbon monoxide in smoke can put you into a deeper sleep,” he explains.

“Without a working smoke alarm, you may not wake up if there is a fire. Smoke alarms alert you quickly and give you and your family valuable time to escape.”

As well as the daily operation of electric appliances, those used for changing seasons can also provide a housefire risk, such as a malfunctioning air conditioner

The CFA also urges homeowners to never leave cooking unattended in the kitchen, as this is a leading cause of home fires. Lithium-ion battery-powered devices should also be monitored during charging, as lithium-ion battery fires are on the rise.

When must a smoke alarm be replaced?

Working smoke alarms play are pivotal to saving lives.

The CFA recommends that all smoke alarms in the home should be powered by a 10-year lithium battery, and should all 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.

Regardless of the type of smoke alarm you have, all smoke alarms should be replaced every 10 years.


Hands installing fire alarm

It takes just a few minutes to clean and test a smoke alarm. Image: Getty

How to check and maintain a smoke alarm

Install smoke alarms in every room 

With more than 70 per cent of fatal house fires starting in bedrooms and lounge rooms, the CFA recommends ensuring that every bedroom, living area and hallway is fitted with a smoke alarm, and that all smoke alarms are interconnected.

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 effectively. 


Qualified professional changing smoke alarm in a home

Leave it to a qualified 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 may become particularly sensitive to dust particles in the air. So, as well as regularly cleaning smoke alarms, be mindful of their age too.  

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. 

If you’re unsure how your to install or charge a smoke alarm yourself, you can get a qualified professional to assist. 

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.

Smoke alarms and rental properties

Regular smoke alarm checks should be conducted in rental properties to ensure safety for tenants. Rental property owners must ensure their property meets the legal standards for house safety.

A Smoke Alarm Safety Check can be added to a rental property inspection. The check includes an assessment of all smoke alarm units, their positioning, cleaning and testing to ensure your home is safe and liveable for you and your family. 


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