Residents urged to replace old smoke alarms

Cheshire Fire and Rescue Service is urging residents living in homes built between 1992 and 2008 to have their hard-wired smoke alarms replaced.

Research into their longevity has concluded that hard-wired as well as battery-operated devices should be replaced every 10 years, or sooner if they do not respond properly when tested.

The manufacturing industry also recommends that smoke alarm detector heads should be replaced every decade.

Nick Evans, Head of Prevention at Cheshire Fire and Rescue Service

Yet Nick Evans, Head of Prevention at Cheshire Fire and Rescue Service, says countless Cheshire homes are being protected by smoke alarms that are more than 10 years old, with misguided faith in hard-wired alarms being a particular concern.

He said: “Smoke alarms save lives – they detect fires in their early stages and give a loud audible warning and they help you to save your home and the lives of your family.

“But simply having smoke alarms in your home is not enough – you have to be sure that they are working.

“People are generally aware that battery-operated smoke alarms need to be replaced every 10 years, but they seem to think that mains-wired alarms will last forever.

“Everything has a shelf life, and with mains-wired alarms using the same technology as battery-powered ones their detector heads should also be replaced every 10 years.”

In 1992 the Building Regulations were amended requiring every new build to have mains-wired interconnected smoke alarms installed.

So all homes built in Cheshire between 1992 and 2008 have smoke alarms that need replacing, unless the homeowners have already replaced them over the past decade.

Nick added: “Some of these homes have smoke alarms that are now nearly 30 years old and desperately need replacing.

“With contaminants such as dust, insects, grease and nicotine, over time the smoke alarm chamber is susceptible to becoming excessively sensitive or insensitive. This may lead to either an increase in nuisance false alarms, or to it eventually becoming unable to detect smoke.

“Similarly, as smoke alarms get older faults are more likely to occur.

“Corrosion of electrical circuitry and disconnected power supply is another possible problem with hard-wired alarms.

“Smoke alarms should be tested regularly, but the tests may not be reliable with old alarms. You may get a bleep when you press the test button but this may give a false impression of the alarm being okay.

“The only way to be sure that a smoke alarm over 10 years old will work properly when you need it to is to have its smoke detector head replacing. This needs to be done by a qualified electrician with mains-wired alarms, but the cost is a small price to pay for knowing that the alarm will alert you should a potentially life-threatening fire start in your home.”

There are currently two types of smoke alarms on the market, ionisation and optical (also described as photoelectric or photoelectronic).

• Ionisation alarms: Costing from under £5, these are by far the cheapest smoke alarms you can buy, but this does not mean they are in any way less effective. They are marginally less sensitive to slow burning and smouldering fires that give off larger quantities of smoke before flaming but will detect flaming fires such as chip pans quickly before the smoke gets too thick.
• Optical alarms: These are more expensive but more effective at detecting larger particles of smoke that are given off by slow burning fires, such as smouldering foam filled upholstery and overheated PVC wiring.

The two types look similar and are powered by battery, mains electricity or both.

When deciding on which type of smoke alarms to buy, you should consider which type of fire is more likely to occur in your home. However, the best protection would be to fit both and make sure that they have a continuous power supply, such as mains power with a back-up battery.

Any smoke alarm that you buy should meet British Standard BS EN 14604:2005 and carry the well-known Kitemark.

Heat detectors are recommended to detect fires in kitchens.