An allegedly “dangerous” type of smoke alarm is installed in more than half of Australian homes despite fire authorities advising against it, according to fire safety experts.
There are two main kinds of smoke detectors – ionisation and photoelectric. Ionisation alarms are good at detecting flaming fires, whereas photoelectric are more effective at detecting smouldering fires (slow-burning, smokey fires).
While both types are legal by Australian standards, there has been a global shift in recent years away from ionisation alarms towards use of photoelectric alarms, with critics claiming ionisation detectors are “actually quite dangerous”.
But many consumers opt for an ionisation alarm simply because they are generally cheaper.
David Isaac, a leading fire protection engineer with almost 50 years of experience in the industry, said ionisation alarms often give people a false sense of security.
“People tend to assume that because these detectors can often be a nuisance – going off all the time when you burn toast – that they must be quite sensitive,” he told The New Daily.
“But they don’t detect visible smoke.
“Smouldering fires can be lethal. If the alarm doesn’t detect it until something bursts into flames, it could be too late and you’d be lucky to get out alive.”
Mr Isaac said that more than 30 per cent of Australians remove their ionisation detector within two years due to nuisance alarms, leaving them with no alarm at all.
“The photoelectric alarms won’t go off unless you cause visible smoke,” he said.
“Some people argue that ionisation alarms are better than photoelectric devices in detecting a flame, but we are talking a matter of seconds –compared to the 30-minute-plus delay in the ionisation alarm detecting the beginnings of a fire.”
How to tell what kind of alarm you have
Mr Isaac advised consumers with ionisation alarms to immediately replace them with photoelectric, ideally with one detector in each room of the house.
He said a consumer can differentiate between the two different types of alarms because an ionisation alarm is required to have a radioactive symbol on the back due to its materials. If your alarm has this symbol, you should replace it, Mr Isaac said.
Another indication is if your alarm is often set off due to cooking fumes or burnt toast, he added.
The Australasian Fire and Emergency Service Authorities Council recommends photoelectric smoke alarms when installing or replacing existing smoke alarms, according to Melbourne’s Metropolitan Fire Brigade.
They are also the alarms used for commercial purposes, such as in hotels and hospitals.
Backlash from retailers
The allegedly inferior ionisation smoke alarms are being phased out in Queensland and the Northern Territory, and have been outlawed in some United States jurisdictions and in Europe.
Major retailers in New Zealand, including Mitre 10 and Bunnings, have begun removing these alarms from store shelves after a report by the country’s consumer watchdog found the devices performed poorly.
But Australian retailers have been less responsive.
When asked whether it had any plans to pull ionisation devices from shelves, Officeworks told The New Daily that all of its products “meet relevant state-specific safety regulations”.
The New Daily also contacted Bunnings, Harvey Norman and Mitre 10 but received no response by deadline.
CSIRO targeted for controversial data
The federal government’s chief scientific research body, CSIRO, runs a smoke alarm testing facility. It is being taken to the Administrative Appeals Tribunal after refusing to reveal certain testing data under freedom of information, the ABC reported.
Mr Isaac alleged that the data will show that ionisation smoke alarms do not activate until the obscuration – or the thickness of smoke – is more than four times the threshold permitted for photoelectric smoke alarms.
He said the release of this data could have serious ramifications for smoke alarm manufacturers.
A CSIRO spokesman said the data in question came as a result of tests that are “commercial-in-confidence”.
“We do not release customer test data that we hold to any other party,” he said.
“We provide testing in accordance with the current Australian Standard, which permits both photoelectric and ionisation technologies.”