Consumer NZ is calling for retailers to stop selling ionisation-type of smoke alarms, after testing found they performed poorly.
The organisation tested fire alarms and found while both ionisation and photoelectric alarms picked up fires, the ionisation-type gave much less warning of smouldering fires, such as those caused by faulty electrical wiring, curtains draped over a heater, or a hot ember igniting upholstery foam.
Smouldering fires were the most deadly, Consumer NZ head of testing Dr Paul Smith said.
"They're more likely to happen overnight when you're asleep. The fast flaming ones are things like cooking fires and you're likely to be actually up and awake when those are on."
Consumer NZ advised people to check which type of smoke alarm they have in their homes and rental properties.
"You can identify an ionisation alarm from a radioactive symbol somewhere on the alarm body - it may be underneath, so you might need to remove it to check."
Consumer NZ and the Fire and Emergency recommended people buy photoelectric alarms, with a long-life battery.
All alarms would respond to a fire eventually, he said, but ionisation alarms were not as effective at picking up smoke.
"The difference is whether they respond to visible smoke. A smouldering fire can fill a home with deadly smoke long before it bursts into flames," he said.
Some distributors had told Consumer NZ they were phasing out the alarms, and last year the Warehouse had stopped selling them, Dr Smith said.
"We are struggling to find any reason why they're still being sold, other than that they're a cheaper version [of alarm]."
The alarms were still available at hardware stores such as Mitre 10, Placemakers, and Bunnings.
Some territories in Australia and some countries had banned ionisation alarms, but in those cases working alarms could be kept, but when being replaced they had to be replaced with photoelectric alarms.
Advice on smoke alarms:
- Not to remove working ionisation alarms - any alarm is better than no alarm
- If only ionisation alarms are fitted, you should also fit photoelectric models at least in hallways and escape routes
- Landlords have to ensure working smoke alarms are installed at the start of a tenancy. Existing ionisation alarms can stay where they are, but all new smoke alarms must be photoelectric models with a long-life battery
- Tenants must not remove smoke alarms, and are responsible for replacing dead batteries