The recent 60 Minutes story on smoke detectors has prompted a number of clients to ask us about the safety and effectiveness of their existing smoke alarms.
The story featured fire safety expert David Isaac, who expressed concern that some smoke detectors were too slow to react and would not allow the occupants of a home enough time to safely escape in the event of a fire.
There are two types of smoke detector available, Ionisation and Photoelectric, and they both detect fires differently.
The ionisation type is better at detecting fast developing fires with lots of flames, while the photoelectric type is better at detecting the slow, smouldering type of fire which can produce a lot of smoke before there are any flames.
Ionisation types are also more susceptible to false alarms from burnt toast and even bathroom steam. Unfortunately this often leads to people disabling them, with sometimes tragic consequences.
While both types of smoke alarm will detect a fire, David Isaac believes the photoelectric type provides better protection.
By the time a smouldering fire progresses to the flaming stage it may have produced quite a lot of smoke, already incapacitating the sleeping occupants of a home, or making it very difficult for them to escape the burning building.
Both types of smoke alarm comply with Australian Standard AS3876, so why do over 90% of Australian homes have an ionisation type detector?
Until quite recently, photoelectric smoke alarms were three or four times the price of an ionisation type detector. When faced with spending either $29 or $89 per detector most consumers have selected the cheaper option.
So, why don’t they make a smoke alarm that combines both methods of detection?
Actually there are dual mode smoke alarms available, however at the moment they are all 9 volt battery models. We have not yet seen a 240 volt version of the dual sensor smoke alarm.
It is important to note, that these 9v battery operated dual mode alarms do not comply with current Tasmanian regulations for smoke detectors in rental properties and new homes. In these properties your smoke detector, (ionisation or photoelectric) must be 240 volt hard wired or have a 10 year lithium battery.
If you have a smoke detector in your home it’s most likely the ionisation type, so what should you do?
No matter what type of smoke alarm you have it only provides protection if it’s in working order so you should change the batteries and test your alarms regularly, as per the manufacturer’s instructions.
Photoelectric smoke alarms are now much cheaper than they used to be so if you are considering replacing your old ionisation models please give us a call to obtain an obligation free quotation.
Phone Mance Electrical on 6331 4711.
