Electrical Inspection and Testing

Smoke Alarms

You are more than twice as likely to die in a fire at home if you haven't got a smoke alarm. A smoke alarm is the easiest way to alert you to the danger of fire, giving you precious time to escape.

XS Engineering will be able to help you select the correct type of smoke alarms for your premises, install the smoke alarms and thereafter commission them.

How many smoke alarms do you need?

The more alarms you have, the safer you'll be. At minimum you should have one on each floor. However, if you have only one alarm and two floors, put it somewhere you’ll be able to hear it when you're asleep. If you have a TV or other large electrical appliance (such as a computer) in any of the bedrooms, you should fit a smoke alarm there too.

Installing a smoke alarm

Have your smoke alarm professionally installed and commissioned. XS Engineering will be able to assist you with this.
The best place for the smoke alarm is on the ceiling, near or at the middle of the room or hall. The alarm should be at least 30cm (one foot) away from a wall or light.

Types of smoke alarms

There are two types of smoke alarm:

Ionisation alarms
These are the cheapest and most readily available and are very sensitive to flaming fires (ones that burn fiercely such as chip-pan fires). Ionisation alarms will detect flaming fires before the smoke gets too thick.

Optical alarms
These are more expensive and more effective at detecting slow-burning fires (such as smouldering foam-filled furniture or overheated wiring). Optical alarms are less likely to go off accidentally and so are best for ground-floor hallways and for homes on one level.

For the best protection, you should install one of each. However, if you can’t have both, it’s still safer to have either one, rather than none at all.

British Standard Kitemark

Whichever model you choose, you should make sure that it meets British Standard 5446, Part 1 (BS 5446-1) and ideally also carries the British Standard Kitemark. XS Engineering can help you decide which is best for your circumstances.

The different models available

A lot of people forget to check their smoke alarms, so the best choice of power supply is usually the one that lasts longest.

Standard-battery alarms
An ‘ionisation battery alarm’ is the cheapest and most basic smoke alarm available. An ‘optical battery alarm’ is a little more expensive. Both run off 9-volt batteries.

Battery alarms with an emergency light
These come fitted with an emergency light which comes on when the alarm is triggered. They are particularly suitable if someone in your house has hearing difficulties.

Alarms with 10-year batteries
These are slightly more expensive, but you save on the cost of replacing batteries. They are available as ionisation or optical alarms and are fitted with a long-life lithium battery or a sealed power pack that lasts for 10 years.

Models with a ‘hush’ or ‘silence’ button
Some models are available with a 'hush' button which will silence the alarm for a short time. This can be used when cooking, for example. If there is a real fire, giving off lots of smoke, the hush system is overridden and the alarm sounds. These models will continue to remind you they have been silenced by 'chirping' or by displaying a red light.

Mains-powered alarms
These are powered by your home’s electricity supply and need to be installed by qualified electricians. There’s no battery to check, although they are available with battery back-up in case of a power cut.

Interconnecting or linked alarms
Some alarms can be connected to each other so that when one senses smoke, all the alarms in the property sound. They are useful for people with hearing difficulties and also in larger homes.

Mains-powered alarm with strobe light and vibrating pad
These are designed for people who are deaf or have hearing difficulties. If there’s a fire, the alarm alerts you with a flashing light and vibrating pad (which is placed beneath your pillow).

Mains-powered alarm which plugs into a light socket
This type of alarm uses a rechargeable battery that charges up when the light is switched on. It lasts for 10 years and can be silenced or tested by the light switch.

Maintaining your smoke alarm

To keep your smoke alarm in good working order, you should:

test it once a week, by pressing the test button until the alarm sounds

change the battery once a year (unless it’s a ten-year alarm)

replace the whole unit every ten years

For further information on Smoke Alarms, please contact XS Engineering.

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