Wedging a fire door open is the most common fire safety offence in Britain and it happens for a sensible reason: the door is in the way. The answer is not to tell people to stop, which never works, but to fit a device that holds the door open legitimately and releases it when the alarm sounds.
Why wedging is the problem it is
A wedged fire door is a hole in the compartmentation at exactly the point somebody chose it to be, which is usually a busy corridor on an escape route. It also cannot be undone by anyone during a fire, because nobody goes back to kick out a wedge. A door held open by a device releases on alarm without anybody deciding anything, which is the entire difference.
Electromagnetic holders
A magnet on the wall holds the door against a plate on the leaf, powered from the fire alarm system or from a local supply monitored by it. On alarm, or on power failure, the magnet releases and the closer shuts the door. These are the standard solution on doors that genuinely need to stand open, and they are an interface on the cause and effect matrix that must be tested at every service visit.
Acoustic and free swing devices
Acoustic hold open devices fit to the door, listen for the alarm sounder and release on hearing it, so they need no wiring. They are useful for retrofit where cabling is impractical, and they depend on the sounder being audible at the door, which should be verified rather than assumed. Free swing closers achieve a similar outcome differently, letting the door move freely until the alarm engages the closer.
What is not a hold open device
A wedge. A fire extinguisher. A bin. A hook and eye. A doorstop screwed to the floor. None of these releases on alarm, and the last one is worse than a wedge because it looks deliberate. If a door needs to stand open, fit a device that is linked to the alarm; if it does not, remove whatever is holding it and find out why somebody put it there.
Questions people ask about fire door hold open device
Is it legal to hold a fire door open?
Yes, with a device that releases the door on the fire alarm operating or on power failure. Holding it open with a wedge or any other object that does not release is not.
Do hold open devices need wiring?
Electromagnetic holders do, usually from the fire alarm system. Acoustic devices listen for the sounder instead and need no cabling, provided the sounder is genuinely audible at the door.
Do hold open devices need testing?
Yes. They are an output of the fire alarm system and belong in the cause and effect matrix, so releasing them should be part of the periodic service and recorded.