Ei Professional Smoke Alarms and Smoke Detectors

Q: What is a Smoke Alarm?

A: A smoke alarm is a self-contained electronic device that incorporates a means of detecting smoke (the smoke sensor) and a means of giving an audible alarm (the alarm or sounder or buzzer). By sensing smoke in the early stages of a fire and sounding a loud warning alarm, a smoke alarm gives an early warning of fire and buys you those precious few minutes for you and your family to get out safely.

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Q: What types of Smoke Alarms are there?

A: There are two types of smoke alarm - Ionisation and Optical (also described as Photoelectric).

Ionization smoke alarms are very sensitive to small smoke particles, produced by flaming, fast fires such as from a chip pan. They are marginally less sensitive to slow burning and smouldering fires, which give off larger quantities of smoke before flaming occurs.

Optical smoke alarms are more effective at detecting larger smoke particles produced by slow-burning fires such as smouldering foam-filled upholstery and overheated PVC wiring. They are marginally less sensitive to flaming fires.

Each type looks similar and is powered by a battery or mains electricity or by a combination of both. Some have additional features such as an escape light (can light-up the escape route) and a silencer button (for use where false alarms can be a nuisance e.g. when cooking). Some are interconnectable so that smoke detected by one smoke alarm will cause all the other units to alarm.

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Q: What type of Smoke Alarm should I fit?

A: As one's home is liable to have both types of fire - fast flaming fires from cooking and slow burning smouldering fires from furniture upholstery or wiring, ideally as a minimum level of protection one should fit at least one smoke alarm of each type i.e. one Ionisation and one Optical.

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Q: How many Smoke Alarms should I fit?

A: As a minimum level of protection, one should fit two smoke alarms - one Ionisation and one Optical. If your home has more than one floor, at least one smoke alarm should be fitted on each level. A combination of optical and ionisation, preferably interconnected will give the best protection. For maximum protection a smoke alarm should be fitted in each room of the house (except kitchen, bathroom or garage - heat detectors are recommended for these rooms). Again a mix of optical and ionisation alarms is recommended and ideally should be interconnected.

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Q: Where should I not fit a Smoke Alarm?

A: Do not fit a smoke alarm in the kitchen (cooking fumes may trigger a nuisance alarm) or bathroom (steam may trigger a nuisance alarm) or in a garage (exhaust fumes may set it off). In these cases we would recommend a heat alarm to provide extra protection.

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Q: What rooms should I fit a Smoke Alarm in?

A: All rooms except kitchen, bathroom, garage should have a smoke alarm fitted i.e. living room, bedrooms and hallway and landings also.

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Q: In a room, where exactly do I fit my Smoke Alarms?

A: Smoke alarms should be installed on the ceiling [at least 30 centimetres (12 inches) away from any wall or light fittings] or if fitted on a side wall, not more than 15 to 30 centimetres (6 to 12 inches) below the ceiling. Be sure to follow the manufacturers' directions as set out in the instruction leaflet supplied with the smoke alarm.

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Q: Are Smoke Alarms difficult to install?

A: Absolutely not. In most cases all you need is a screwdriver. Be sure to follow the manufacturers' directions as set out in the instruction leaflet. If you are uncomfortable standing on a ladder, you should get a neighbour or friend to help you install. If one decides to fit mains powered smoke alarms, a qualified electrician should be contracted to install and again it is important to follow the manufacturer's instructions.

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Q: Where can I buy Smoke Alarms?

A: Most DIY stores, hardware and electrical shops, many supermarkets and department stores carry a range of smoke alarms, the majority of which are battery powered and easy to install. Always buy an alarm that conforms to British Standard. This means the alarm has achieved a standard acceptable to the British Standards Institute (BSI). Smoke Alarms should meet BS 5446 Part 1 and carry the well known Kitemark.

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Q: Smoke Alarms with additional features. What are they and should I consider fitting them?

A: In addition to the 2 basic types of smoke alarm, Ionisation and Optical, a mixture of which is recommended, some have additional features:

An Escape Light feature.
An escape light smoke alarm has a built-in light, powered by a separate battery which lights-up in the event of the smoke alarm being activated. Such a smoke alarm can be very useful, in a fire situation where electricity is gone, to help light up the escape route from your house. Suggested locations would be hallways, landings etc. Now available from Ei Electronics with both optical and ionisation sensors.

A Silencer Button feature.
A smoke alarm with a Silencer Button can usefully be fitted near a kitchen area for example where cooking fumes may cause a nuisance alarm. The Silencer Button enables one to temporarily silence the alarm if it is a nuisance alarm. The smoke alarm will however automatically re-alarm if the smoke situation remains. Now available from Ei Electronics with both optical and ionisation sensors.

Interconnect feature.
Interconnection is a very useful feature enabling you to interconnect all your smoke alarms using twin core wire. When smoke alarms are interconnected, if one smoke alarm senses smoke at one point in the home, all smoke alarms will simultaneously alarm. Thus a developing fire situation in the living room will trigger the smoke alarms in the bedroom for example - a very desirable feature as many fire situations develop during the night when the family is asleep.

10 Year Battery Powered Smoke Alarm.
Normally the 9 volt battery must be replaced every year but this chore is often forgotten and with tragic consequences. It is now possible to buy a battery powered smoke alarm that is powered for the life of the smoke alarm i.e. 10 years. This can be especially useful feature for elderly people. Now available from Ei Electronics with both optical and ionisation sensors.

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Q: Any tips in taking care of my Smoke Alarm?

A: Smoke alarms are very easy to take care of. There are three steps to remember.

1. Once a month, check the alarm by pressing the test button.

2. Replace the batteries once a year or when the alarm starts making a 'chirping' noise. A smoke alarm will start to make a 'chirping' noise when the battery needs to be replaced.Alternatively you may prefer to replace once a year - pick a holiday or your birthday for example and replace the batteries each year on that date. Long Life smoke alarms with a 10 year life battery are now on the market - these alarms are designed to be replaced as a whole unit, thus avoiding the need for battery replacement.

3. Keep it clean. Dust, debris and cobwebs can interfere with its operation, so vacuum over and around the smoke alarm regularly

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Q: How long will my Smoke Alarm last?

A: About 8 to 10 years, after which it should be replaced. Many smoke alarms carry a label with the recommended 'Replace-by date' - if not, you may write the purchase date on the side of the unit and replace in 10 years from that date. Always follow the manufacturers' instructions for replacement.

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Q: What should I do if my Smoke Alarm 'chirps'?

A: Smoke alarms are designed to make an intermittent 'chirp' to indicate that the battery needs to be replaced. So once your smoke alarm begins to 'chirp', replace the battery at once.

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Q: What if my Smoke Alarm goes off while I'm cooking?

A: Then its doing it's job! Do not disable your smoke alarm if it alarms due to cooking or other non-fire causes, because you may not remember to put the battery back in the alarm after cooking. Instead, clear the air by waving a towel near the alarm, leaving the batteries in place. If such 'nuisance' alarms from cooking fumes persist, you may consider re-locating the smoke alarm or you may consider fitting a smoke alarm with a 'silencer' feature - this feature allows you to temporarily silence the smoke alarm but it is not disabled and will re-alarm if the smoke situation persists.

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Q: Will cigarette smoke cause my Smoke Alarm to alarm?

A: Normally cigarette smoke should not activate a smoke alarm. One should not refrain from fitting a smoke alarm in a room where there is likely to be smoking - in fact the opposite is true, because cigarette smoking material is a major cause of fires and deaths from fire in the home.

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Q: Have Smoke Alarms got limitations?

A: Smoke alarms have significantly helped to reduce the number of fire fatalities in countries where they are widely installed.

However independent authorities have stated that they may be ineffective in up to 35% of all fires. There are a number of reasons for this:

Smoke alarms will not work if the batteries are depleted or are not properly connected or if the wrong type of battery is used. Test regularly and replace batteries at least yearly or when depleted.

Smoke alarms will not detect fire if sufficient smoke does not reach the alarm. Smoke may be prevented from reaching the Alarm if the fire is too far away, for example, if the fire is on another floor, behind a closed door, in a chimney, in a wall cavity or if the prevailing air drafts carry the smoke away. Installing smoke alarms on both sides of closed doors and installing more than one smoke alarm as recommended, very significantly improve the probability of early detection.

The smoke alarm may not be heard.

A smoke alarm may not wake a person who has taken drugs or alcohol.

Smoke alarms may not detect every type of fire to give sufficient early warning. They may be ineffective with: fires caused by smoking in bed, escaping gas, violent explosions, poor storage of flammable rags and/or liquids, (for example petrol, paint, spirits etc), overloaded electrical circuits, arson, children playing with matches. This is because a person can be rapidly overcome/injured by fumes or flames from adjacent fires. A smoke alarm will provide protection by giving warning to people remote from the fire, but for people too near the fire the warning could come too late.

Smoke alarms don't last indefinitely. The manufacturer recommends replacement after 10 years as a precaution.

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Q: Are there Smoke Alarms for people with hearing impairment?

A: Many people whose hearing is not severely impaired are still able to hear a conventional smoke alarm. It is a good idea to interconnect two or more alarms - in this way, smoke detected in the living room will set off another alarm in the bedroom. Smoke alarms can be interconnected using twin core wire.

For people who would not be able to hear a conventional smoke alarm there are special Smoke Alarms for the Deaf or Hard of Hearing available which make use of a vibrating pad and/or a flashing light in addition to the audible warning.

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