A fire door looks like any other solid door. What makes it different is that it has been tested in a furnace, and it only keeps that result if it’s built, installed and looked after exactly as tested. This guide explains what a fire door is, what the numbers on its tag mean, and what “compliant” means in practice.
A fire door is a system, not a door
The Australian Standard for fire doors is AS 1905.1. It calls them fire-resistant doorsets, and the word “set” matters. A fire door is the whole assembly: the door leaf, the frame and how it’s fixed to the wall, the hinges, the latch, the closer, any seals or glass, and every fitting on it.
A manufacturer builds a sample doorset and a testing laboratory puts it in a furnace. If it passes, that exact combination of parts, fitted that exact way, is what we mean by a tested system. A door in your building is a fire door because it matches that tested system.
So you can’t make a fire door by choosing a heavy door, and you can’t keep one by replacing parts with whatever fits. Swap the closer, add a lock, or refit the frame differently, and the test result may no longer apply. The standard does allow some changes, but many of them need a written assessment from a registered testing laboratory first.
Where fire doors are required
The National Construction Code (NCC) says where a building needs fire doors. In NSW the 2022 edition still applies, and the 2025 edition starts on 1 May 2027. The usual places are:
- doors into fire stairs and other fire-isolated exits
- doors in fire walls, which divide a building into separate fire compartments
- doors into service shafts in larger buildings
- in apartment buildings three or more storeys high, the front door of each apartment where it opens onto a shared corridor or lobby
In lower apartment buildings, the front door usually needs to be self-closing, tight-fitting and solid-core, at least 35 mm thick. That’s not a fire door. It has no fire rating and no tag, and it’s checked against different rules.
A smoke door isn’t a fire door either. It’s built to stop smoke passing through a doorway, not to hold back fire.
Your building’s fire safety schedule lists which doors are fire doors and which standard they have to meet. If you’re not sure what a door is meant to be, start there.
What -/60/30 means
Every fire door has a fire resistance level (FRL). It’s three numbers, in minutes, from the furnace test:
| Part | Example | What it measures |
|---|---|---|
| Structural adequacy | – | Whether it keeps carrying a load. Doors don’t carry loads, so this is always a dash |
| Integrity | 60 | How long it stops flames and hot gases getting through |
| Insulation | 30 | How long the side away from the fire stays cool enough not to set things alight |
So -/60/30, the most common rating, means 60 minutes of integrity and 30 minutes of insulation in the test. It’s a grading from a controlled test, not a promise of exactly an hour in a real fire. Other ratings exist, such as -/120/30 for some fire walls.
Reading the tag
A fire door carries two small metal tags, one on the edge of the door leaf and one on the frame. On an ordinary hinged door they’re on the hinge side, at about shoulder height. They’re riveted or nailed on, and the details are stamped into the metal.
Under the current standard, the tags show:
- the standard the door was tested to, and its year
- the FRL
- who made the door leaf, or the frame
- who certified the doorset
- the year it was made
- on the door leaf, a unique door number that matches the building’s door records
The tag is the door’s proof of identity. If it’s painted over, pulled off or unreadable, nobody can show the door is what it’s meant to be, even if it’s in good condition. A missing or unreadable tag is recorded as a finding at inspection.
A tag can’t simply be added to a door that’s already in a building. Tagging a door certifies how it was made and installed, and on an existing door that usually can’t be proven. Specialist laboratory testing of an existing door is possible, but it usually costs more than a replacement and still can’t show when or how the door was installed. Where a tag is missing, the usual answer is a new, tagged doorset.
What “compliant” means
A fire door is compliant when all of these are true:
- It matches its tested system, or any differences have been assessed and allowed.
- It closes itself from any position. Let go of the door at any angle and it should swing shut. The closer should slow the door near the end of a hard push open, so it doesn’t slam into the wall.
- It latches itself. Once it’s closed, the latch should hold it shut without anyone turning a key or handle. Anything that could stop it latching, such as a deadbolt, a swing bar or a latch that can be left open, isn’t allowed.
- The gaps are right. Around the top and sides, the average gap between the door and the frame should be no more than 3 mm. Underneath, there should be 3 to 10 mm above the floor covering, or no more than 25 mm above a concrete or other non-combustible threshold.
- It’s only held open by an approved device. Some fire doors stay open during the day on a magnetic hold-open linked to the fire alarm or a smoke detector. If the alarm goes off or the power fails, the door has to release and close. Wedges, hooks and door stops aren’t approved devices.
- It’s tagged, and the paperwork exists. When fire doors are installed, the owner should get a numbered certificate and a door manual listing every fire door in the building, its rating and its parts. A paper copy of the manual is kept on site.
- It’s maintained. Under AS 1851-2012, fire doors are inspected every six months. The front doors of individual apartments or tenancies, known as sole-occupancy units (SOUs), can be extended to once every 12 months.
What usually breaks compliance
Most non-compliant fire doors were compliant once. Something changed afterwards, usually with good intentions:
- a new handle, lock or deadbolt that isn’t part of the tested system
- a peephole, letterbox slot or pet door cut through the leaf
- a closer disconnected because the door was “too heavy”
- a wedge or hook to keep the door open
- seals painted over or torn off
- new carpet or tiles that change the gap under the door
- a door planed down to stop it sticking, until the gaps are too wide
- the tag painted over during a repaint
If you’re planning any change to a fire door, ask before you make it. Plenty of changes are possible with the right parts. Putting a change right afterwards costs more.
Older doors
AS 1905.1 has had several editions, and the tag on an older door may name 1990, 1997 or 2005. Each edition set its own list of what goes on the tag, so an older tag may show different details from a new one. A door isn’t non-compliant just because its tag shows an older edition. It’s generally assessed against what applied when it was approved and installed, and it has to be maintained so it still performs to that standard. For doors prior to 1986, check if the fire door is constructed using asbestos. Asbestos fire doors are classed as “Friable” and cannot be worked on, and can only be removed by a Class A licensed asbestos removal company.
When an older fire door is replaced, the new doorset is made and tagged to the current edition.