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Helping Protect Your Home Against The Risk Of A Fire

Helping Protect Your Home Against The Risk Of A Fire

The general rule is that any type of early detection is better than none, and will provide valuable seconds to allow safe escape from a house when needed

Smoke and heat alarms are generally devices that are self-contained, incorporating the means of detection as well often a visual indication and a loud audible alarm. They vary in size according to type i.e. battery only powered, or mains powered with a battery backup. Some ultra modern devices are deliberately made smaller so as to be more aesthetically pleasing, but they all do the same important job.

Detectors are normally fitted to ceilings, although there are some makes that will work as efficiently mounted vertically on walls. Please be sure to check any fitting instructions carefully to ensure that optimum performance is ensured.

What types of detection is available?

There are mainly four common types of detection installed in homes.

Ionisation, optical (also referred to as photoelectric), heat and combination devices, which are often smoke and heat but can also be smoke and carbon monoxide.

Our guidance would be to have a separate carbon monoxide detector that can be fitted in accordance with its specific requirements


These are generally the least expensive. They are more sensitive to small particles of smoke that is associated with fast flaming fires, such as paper and wood, and will detect this type of fire before the smoke gets too thick. They are less sensitive to slower burning and smouldering fires which give off larger quantities of smoke before flaming occurs. They are the main culprits for false alarms, being over-sensitive when fitted in close proximity to kitchens.


These tend to be more expensive, but are more effective in detecting larger particles of smoke produced by slow-burning fires, such as smouldering foam-filled upholstery and overheated PVC wiring, which are the sources of many fires especially in the homes of the elderly.  They tend to be less sensitive to fast flaming fires. Optical alarms can be installed near (not in) kitchens, as they are less likely than ionisation alarms to go off when toast is burned.  They can provide an early warning of fire which is why they are ideally located in halls, on landings, in stairwells, and main living areas in a house.

Heat Alarms

They detect the presence of an increase in temperature from a fire and are insensitive to smoke. They are therefore the detector to be installed in kitchens or areas such as a boiler room. They cover a relatively small area of a room, so potentially several heat alarms need to be installed in a large kitchen.

Combined Detection

Combination detectors can have advantages where you want to increase the possible speed of detection and also helo reduce false alarms.

Each type of detector looks very similar and they are either powered exclusively by battery, or according to current building regulation standards for new properties, to be mains powered with a battery back up. They should also have the ability to be interlinked, so if one goes off, they all go off. The back up battery type may be a normal alkaline cell or in more expensive units a lithium battery. Make sure to check the warranty on lithium battery devices, as although the battery is expected to last 10 years, the actual warranty on the detector may only be 5 years. This is very common with all major manufacturers.

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