The Life Savers: Smoke Alarms

By 26th November 2016News

By now, everyone knows the valuable life-saving asset that rests above your head; a smoke alarm.

We have all seen the campaigns to test your smoke alarms each month just to make sure the battery is still operational. We know it’s essential yet there is still a lot of confusion as to the different types of smoke and heat alarm, ionisation and optical, etc. This post will carefully explain each type of fire alarm and where it is recommended to be installed. We will also cover other fire safety and prevention tips.


Have you ever burnt a piece of toast and set off  the fire alarm first thing in the morning? Chances are that this is an Ionisation alarm. These are your most common type of smoke alarm. They typically detect ‘fast flaming’ fires meaning that they can detect small particles of smoke quickly, something given off by the flames of a fire. These are the cheapest type of smoke alarm available.


In broad terms (although not entirely accurate) Ionisation is for fast flaming fires, Optical is for slow burning fires. Optical alarms detect larger smoke particles given off by smouldering and although both Optical and Ionisation alarms can detect these slow burning fires, optical wins in the speed of detection. These are slightly more expensive than ionisation alarms but they are also very common on the market.

Heat Alarms

Heat alarms do pretty much what it says on the tin. They detect heat, not smoke. These make it perfect for kitchens as they are immune to smoke and so your morning toast won’t set it off but the heat of a chip pan fire will. Word of caution; these have a small operating range so if you have a large kitchen then you may need to install more than one.

Combined Optical Smoke and Heat Alarms

Through the use of Thermoptek technology, these alarms have the best of both worlds. They are becoming an increasingly popular choice to put in households and businesses for good reason. They cut down the possibility of false alarms and increase the speed of detecting fires.

Carbon Monoxide Alarms

CO or Carbon Monoxide is known as the silent killer to many. You can’t smell it, it’s invisible, and it is deadly. These alarms are a must and are now required by law in a rented property where there is a solid fuel appliance. It is highly recommended that you place CO alarms near any solid fuel source but also next to; Sleeping Areas, Stoves, Fires and Boilers, Water Heaters, Paraffin Heaters, General Gas Wall Heaters, and LPG Gas Appliances in Caravans & Boats.[1]

Combined Smoke and Carbon Monoxide Alarms

These have become popular for the obvious reason that they take up less space and are easier to install than two separate alarms. These are commonly fitted in bedrooms but are useful throughout the house.

Where to install them?

Remember the burnt toast situation? You probably have the wrong type of alarm in your kitchen. For kitchens it is recommended to use heat alarms as this will stop false alarms and will still keep you safe. Optical alarms or optical and heat alarms are recommended to be placed just outside the kitchen area such as hallways, living rooms, and bedrooms. Ionisation alarms should be placed on landings or combined optical smoke/heat alarms.

As we have stated before (although you can never say this enough with safety) Carbon monoxide alarms should be placed in or near Sleeping Areas, Stoves, Fires and Boilers, Water Heaters, Paraffin Heaters, General Gas Wall Heaters, and LPG Gas Appliances in Caravans & Boats.

Now a big question; How many do I need? This varies from person to person and building to building. The short answer is there is no real upper limit. Most fire brigades recommend 1 in each bedroom, 1 on each floor of the building and at least one (depending on size) in your living room, kitchen, and garage. The only place that you shouldn’t put a smoke alarm is in your bathroom. This is because the regularity of steam generated in this room can damage the alarm but also keep setting it off.

Apart from where to install them, you should also have a qualified electrician install any and all mains powered or mains & battery powered alarms. Even so, test these out once a month to ensure they are still working properly. There are also Interlink alarms that can be installed that use radio frequencies so that when one alarm sounds, all of them sound so that the whole household is alerted.

Different needs for a business

Business premises have different needs to residential properties; however, the advice still stands. Your business will need a central unit that can alert you. The two most common types of business alarm are conventional and addressable. Both have their distinct advantages so please talk to an approved installer (like us) to come in and asses your business and its needs. The installation should be accredited by a professional body and compliant with the latest regulations.

Obviously the standards are much stricter for businesses however; with proper installation and equipment you can ensure that your place of work is safer than ever.

Extra tips

  • Test your smoke alarms at least once a month to ensure they are working properly.
  • Make sure you have a fire evacuation plan and that you have practiced the drill to ensure that should the worst happen you know what to do.
  • After 10 years it is best to get a whole new alarm
  • Clean and vacuum gently to remove dust particles from blocking the alarm.

After all this I hope that you have a clearer understanding of what each type of smoke alarm does within the household and where you can put them for the best fire safety possible.

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