Smoke Alarms

Last year, the New Zealand Fire Service attended over 3,700 house fires. In over 80% of those fires, smoke alarms were either not installed or not working. 


Smoke alarms are the best possible defence you and your family have from dying in a fire!

Where should I put smoke alarms?

Smoke rises and moves along the ceiling. It will move up stairwells and vertical openings. When it can't rise anymore it will build up, working its way down again. It's because of this that it's important to place smoke alarms on the ceiling to get the earliest warning. If you must position it on the wall put it 100mm away from the ceiling to avoid dead air pockets.

For optimum smoke detection, long life photoelectric smoke alarms should be installed in every bedroom, living area and hallway in the house - on every level. However, this is not always practical. That's why we suggest, at an absolute minimum, that a long life photoelectric smoke alarm should be installed in the hallway closest to the bedrooms. This should be supplemented with other alarms as soon as circumstances permit.

Picture of rooms in your house that should have smoke alarms

Where not to put them.


Picture of where not to put smoke alarms

What sort of smoke alarm should I install?


• they provide a minimum of 10 years smoke detection

• they remove the frustration of fixing the 'flat battery beep' at inconvenient times

• the cost of replacement batteries for standard alarms means the long-life one effectively pays for itself over its lifetime

• elderly don't have to scale ladders to replace batteries annually


Alarm Maintenance

Dust and spider webs can affect smoke alarms. Clean with the vacuum cleaner once a month, and while doing so, test the alarm by pushing the test button. Batteries must be changed once a year, time this to recur on a regular date (such as on New Year's day, daylight saving or a family member's birthday). All smoke alarms will sound a short 'beep' every so often indicating that the battery is going flat.

Smoke alarms have a life expectancy of 10 years. A smoke alarm constantly monitors the air 24 hours a day. At the end of 10 years, it has gone through over 3.5 million monitoring cycles. After this much use, components may become less reliable. This means that as the detector gets older, the potential of failing to detect a fire increases. Smoke alarms that are wired into my electrical system (or burglar alarm) also need to replaced every ten years.

If an alarm regularly responds to smoke from cooking, there are several options to handle this problem. One way is to replace the alarm with one that has a button to silence it for a few minutes. You could move the alarm further away, giving the smoke more time to dissipate.

If the detector is the ionization type, another option is to replace it with a photoelectric. This detector is less sensitive to the smaller particles so is less affected by cooking smoke. The other option is to use a heat detector rather than smoke alarm.

To stop an alarm sounding, you need to clear the air in the sensor chamber. Fanning the alarm with a paper or tea towel is the best method and the alarm will stop automatically. Do not try and disable the alarm by removing the battery.