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Smoke Alarms

Every year in the UK, Fire and Rescue Services are called to more than 600,000 fires, which cause over 800 deaths and 17,000 injuries. Around 10% of these fires, 140 a day, are domestic house fires, which kill nearly 500 people and cause over 11,000 injuries.

Many of these deaths and injuries could be prevented if a smoke alarm had been installed, as they provide an early warning allowing people to escape in time. In fact, you are more than twice as likely to die in a house fire if you do not have a working smoke alarm installed in your home than if you do.

How many alarms should you install?

Simple: the more you have, the safer you’ll be. Ideally you should install an alarm in every room apart from the bathroom and garage, but as a minimum you should have at least one alarm on each floor, where you will hear it when you are asleep.

Choosing a smoke alarm

There are three types of smoke alarm available:

Ionisation alarms: these alarms are sensitive to fast flaming fires, such as chip-pan fires, and are the most commonly found alarms. They are also the cheapest. Best installed in bedrooms.

Optical alarms: these alarms are more sensitive to slow burning fires, such as over-heated wiring or smouldering furniture. They are also less prone to nuisance tripping. Best installed in hallways, landings, living & dining rooms.

Heat alarms: these alarms are best installed in kitchens, where the other alarms are more likely to be activated accidentally by cooking fumes and steam.

Installing and testing

  • Always choose a smoke alarm that carries the British Standard Kitemark.
  • In one storey homes, fit the alarm between the bedrooms and living area.
  • In multi-level homes, fit alarms on each level, at the bottom of the stairs and on each landing at least.
  • Alarms should be fitted on the ceiling, near to the middle of the room or hallway.  They should be at least 30cm (12”) from any light fitting.
  • Alarms should be tested every week, so make sure they are installed where you can reach them.
  • Gently vacuum your alarm every six months to remove dust from the sensor.
  • Once a year, change the battery (unless it has a 10 year battery)
  • When the battery is getting low, an intermittent beep will sound.
  • All smoke alarms should be replaced every 10 years.


Many people forget to test their alarms regularly, so the safest option is to install an alarm with the longest life.

Battery alarms 

These are the most basic, and most common, smoke alarms: an ionisation alarm with a 9-volt battery. Optical alarms are also available with batteries, as are alarms with a light: these are suitable for someone with hearing difficulties and can also help to light an escape route.

Alarms with 10 year batteries are more expensive, but you save on the cost of replacing batteries.

Mains alarms 

These alarms are installed directly onto your mains electricity supply, and need to be installed by a fully qualified electrician. If there is a power cut, they have a battery backup.

Interconnecting mains alarms are also available, suitable for larger properties or people with hearing difficulties. These alarms are linked together so that when one alarm is activated, all the alarms will sound. 

Alarms for people with hearing difficulties 

Smoke alarms are available for deaf people or those with hearing difficulties. They can have a strobe light, and often a vibrating pad to place beneath your pillow.

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