Recent studies show photoelectric smoke alarms could be the best choice for a home.
However, state regulations only specify whether your alarm should be mains or battery-powered. They don’t specify the type of alarm you should install; any Australian Standards-approved ionisation or photoelectric alarm will comply.
Toxic smoke and fumes are a major risk. In a house fire, it’s the flames that do the structural damage, but smoke is the main danger to people. The majority of deaths in fires come from smoke inhalation/poisoning. Modern homes contain a lot of materials — such as wood, wool, nylon and plastics — which, when burning, give out heavy smoke and toxic fumes such as carbon monoxide and cyanide gas. These materials can smoulder for a long time, putting out a lot of smoke and fumes before they burst into actual flames.
If you’re asleep when the fire starts, you could suffer from smoke inhalation before you wake up; in fact, the combination of toxic smoke and reduced oxygen in the air can make waking up more difficult. So it’s important to have an alarm that rapidly detects smoke.
Why choose photoelectric alarms?
Photoelectric smoke alarms are much faster at detecting this dangerous situation than ionisation alarms. Studies have shown that photoelectric alarms typically respond to smoky fires within about three to five minutes — when the level of smoke is still fairly low and escape is relatively easy. Most ionisation alarms take much longer — up to 20 minutes or more — by which time there’s enough smoke to significantly reduce visibility, making escape much more difficult.
The fast-flaming, relatively smokeless fires that ionisation alarms detect quickly are not as common in most domestic situations. When such a fire starts, it’s usually in the kitchen while someone is there and can do something about it. Even if no one’s there, other nearby material usually catches fire quickly and starts giving out smoke. Photoelectric alarms therefore usually detect fast-flaming fires quickly enough.
Fire industry experts agree
Photoelectric smoke alarms are required by Australian standards and the Building Code of Australia for all sleeping areas and exit paths in commercial buildings such as hotels. Industry experts also generally agree that photoelectric smoke alarms should be the first choice for homes — install at least one. Some fire authorities, and most major smoke alarm manufacturers and distributors, recommend having at least one of each type of smoke alarm to cover different fire situations.