Smoke alarms and fire safety at home: types, placement, rules and fire doors

What you'll notice

Most smoke alarm problems are easy to miss until they matter. These are the signs worth acting on.

Types of alarm and how they are powered

There are two main sensing types. Photoelectric alarms detect visible smoke particles and respond earlier to slow, smouldering fires, which are common in homes; ionisation alarms respond to the small particles of fast, flaming fires. Victorian fire services and the Queensland Fire Department recommend photoelectric alarms that meet AS 3786:2014. Queensland's rules now require them and prohibit alarms with an ionisation sensor.

Victoria's fire services note that in Fire and Rescue NSW tests where a fire started in a bedroom with the door closed, the hallway alarms did not activate at all. That is why interconnected alarms in bedrooms matter.

Where alarms should go

As a minimum, most states require an alarm on every storey, between sleeping areas and the rest of the home, in the path people would use to escape. Fire services recommend going further: interconnected alarms in every bedroom, hallway and living area. Alarms go on the ceiling, kept clear of the corner where wall meets ceiling; Boroondara Council gives at least 30 cm from the wall. Avoid spots near kitchens, bathrooms and air-conditioning vents that cause false alarms.

The rules in Queensland and Victoria

Landlords have extra obligations in every state, and when a home is renovated or extended, newer requirements can apply to the new work. The dated milestones table shows when mains-powered and interconnected alarms began for new homes nationally.

Testing, cleaning and replacing

These intervals follow Fire Rescue Victoria and Victorian council guidance. Hardwired alarms must be replaced by a licensed electrician; sealed 10-year battery alarms can usually be fitted by the owner. Never disconnect an alarm because of false alarms; move it or replace it with the right type.

Apartments: fire doors and shared safety systems

In many apartment buildings, each unit's entry door is part of the building's fire safety system: a fire-rated or solid-core door that must close and latch by itself. A fire door usually carries a metal tag on its hinge edge. A door that no longer self-closes, a removed closer, a painted-over tag, an unapproved lock change or a security screen fitted to the door can all compromise it, as strata fire safety specialists explain.

Shared systems, such as fire doors, alarms, extinguishers, exit signs and emergency lighting, are maintained by the owners corporation under state rules, such as Victoria's essential safety measures and NSW's annual fire safety statement. Ask before altering your entry door, and report one that will not close. See strata risks for owners.

Beyond alarms: the rest of home fire safety

Alarms give warning; the house still needs a way out and fewer ways for fire to start. Agree a home escape plan with everyone in the household, keep keys near deadlocked doors, and keep exits clear. Old wiring, overloaded power boards and faulty heaters are common causes of house fires, so read the switchboards and wiring guide, and have gas heaters serviced, as set out in heating, cooling and gas safety. In bushfire-prone areas, see preparing your home for extreme weather.

Common misreads

Worked example: a 1990s house with two hardwired alarms

Illustrative reasoning example, not an inspected property. A 1998 Victorian house has two hardwired alarms in the hallways, dated 2009. The bedrooms have none, and pressing one alarm's test button does not set off the other.

The house meets the requirement it was built to, but the alarms are past 10 years and are not interconnected. The practical upgrade is a licensed electrician replacing them with photoelectric alarms, adding interconnected alarms in each bedroom and the living area. The electrician's certificate goes in the home record.