Smoke and Detectors
Smoke Alarm and Detectors Services in London
The Fire and Rescue Service is called out to over 600,000 times a year for fires which end in over 800 deaths and 17,000 injuries.
An estimated 50,000 of these are house fires that kill nearly 500 and injure over 11,000. Many of these injuries could have been prevented if people had early warnings and were able to escape earlier.
It is a proven fact that you are twice as likely to die in a house fire that has no smoke alarm than one which does. So buying smoke alarms could save the lives of your family and your home.
Smoke alarms are self-contained units that detect smoke in your home (in the early stages of a fire) and set off an alarm to warn you of this usually with a loud beeping sound. Standard smoke detectors are usually about the size of your hand and are fitted in hallways/kitchens to cover most of the house.
Because they detect the smoke in the early stages of the fire it gives you and your family time to evacuate the property in safety.
Types of Smoke Alarms
There are four main types of smoke alarms, Optical, Heat, Ionisation and combined. They are all meant for slightly different uses/areas. Below we go into more detail on each type:
Optical (Photoelectronic):
These are one of the more expensive choices, but much more efficient at detecting larger smoke particles from slow-burning fires, smoldering furniture, and electrical fires. This type of alarm is a little less sensitive to fast flaming fires, these are usually installed near (not in) kitchens because they are less likely than ionisation alarms to go off whenever toast is burned.
Ionisation:
This is the cheapest and most cost-effective type of smoke detector. Ionisation smoke detectors are very sensitive to smaller smoke particles from fast flaming fires like wood and paper. They will detect this type of fire before the smoke thickens giving people more time to escape the house. They are not as sensitive as the optical type for slow-burning fires which give of larger quantities of smoke before flaming occurs. They can also be over-sensitive near kitchens going off when toast is burnt.
Heat Alarms:
Heat alarms are usually used in kitchens, Instead of detecting smoke they detect the increase in temperature from a fire. This type of detector will only cover a small area of a room so we would generally fit a few in larger kitchens.
Combined Optical Smoke and Heat alarms:
This is a combination of a heat alarm and an optical detector in one unit. These units reduce false alarms whilst increasing the speed of which a fire is detected.
Combined smoke and Carbon dioxide alarms:
This type of alarm combines both a smoke detector and a carbon dioxide detector in one ceiling-mounted unit. These units take up less space and reduce the costs involved in making your home safer.
All of these smoke alarms look very similar and are powered either by a battery or mains power (Or both with the battery as a backup power supply). Some smoke detectors can be interlinked so if any smoke detector’s alarm goes off every detector in the house will raise the alarm. This can be done by hard wiring or with radio-interlinked smoke alarms.
The majority of modern smoke alarms have hush buttons for when a false alarm is raised. False alarms can be a nuisance when you are cooking if the alarm goes off you can simply press the hush button and it will silence the alarm. Often after using the hush button there will be a red light flashing or a chirping noise to make the user aware that the alarm has been silenced.
Most standard battery-powered smoke detectors will need the battery replacing once every 12 months. There are alarms on the market with sealed 10-year batteries already in, giving the advantage of not having to replace the batteries annually.
New buildings have to have mains powered alarms fitted as well as any major refurbs. You should make sure that any mains powered alarms have battery back up’s in case the mains power is interrupted. These can be standard alkaline batteries that need replacing yearly or built in rechargeable lithium batteries which will last for the lifetime of the alarm. These must be fitted by qualified electricians.
It is common for false alarms to be set off when cooking or if the toast is burnt. An alarm installed in a kitchen must be a heat alarm rather than a smoke detector to stop this from happening. If installing an alarm just outside of the kitchen an optical smoke alarm or even a combined smoke and heat detector would be ideal, these are less likely to raise a false alarm. Some alarms also come with escape lights, to light the way out of the building and also to alert people that may not hear the alarm.
As well as the lights, there are smoke alarm systems for the deaf and hard of hearing with vibration pads to go under pillows and strobe lights which go off if alarms are raised to alert them whilst asleep.
Which smoke alarms should I choose and where should they be fitted?
There is a general rule for smoke alarm positioning please see below:
Bedrooms:
Optical smoke detectors OR combined optical smoke and heat detector.
Landings:
Ionisation smoke alarms OR Combined optical smoke and heat detector.
Kitchen and Garage:
Heat alarms
It is recommended that you always buy smoke alarms that have been certified to the British or European standard
The number of smoke alarms you should fit in your home varies depending on the size of the property. It is good practice to have an alarm fitted in every room other than the bathroom, and pick the alarm type most suited to each room. Alternatively, if your house is all on one floor one alarm preferably of the optical type may be enough to warn you early of a fire, or if it is a 2 storey house then one alarm on each floor would be fine, a combination of ionisation and optical would be good.
Where should smoke alarms be fitted?
The general rule of practice for fitting smoke alarms is for them to be fitted as close to the center of the room as possible but at least 30 centimeters (12 inches) away from the walls and light fittings. Make sure that it can be heard throughout the home (Especially when sleeping)
If your home is on one level it should be fitted in the hallway between the living and sleeping areas. If you are in a two storey home it should be somewhere where it can be heard when you are asleep (e.g at the top of the stairs near the bedroom).
Smoke alarm maintenance
Smoke alarms require very little maintenance. You should follow the manufacturer’s instructions but generally, these can be used as a guideline:
- Test your smoke alarms when the clocks are changed and vacuum it gently to remove any dust from the sensor
- Change the battery annually (unless it has a sealed ten year battery)
- Replace the alarm after ten years.
Fitting smoke alarms in your home and ensuring they are correctly maintained could give you those few extra minutes that you need to escape safely in case of a fire.
Make sure you plan escape routes from your home for you and your family. If a fire occurs at night you may need to evacuate the house in the dark so it’s a good idea to make sure you have a clear escape route with no tripping hazards to ensure a safe escape.
Make sure you regularly check the battery in your smoke detector replace it as soon as required.