What is a self-closing device?
A self-closing device is the closer fitted to a fire door that returns it fully into its frame after use. Without one working, a fire door provides no protection while it stands open.
Use this diagram
Free to use on your own site, in training material or in a handout, as long as the credit link stays on it. Paste this where you want the diagram to appear.
<figure>
<img src="https://fireoptix.co.uk/glossary/self-closing-device/diagram.svg" alt="self-closing device — diagram from FireOptix" width="880" height="620" loading="lazy">
<figcaption>
<a href="https://fireoptix.co.uk/glossary/self-closing-device">What is a self-closing device?</a> — diagram by
<a href="https://fireoptix.co.uk">FireOptix</a>
</figcaption>
</figure>The device has to close the door completely, including engaging the latch where one is fitted. A door that closes to within an inch of the frame has failed, because the gap it leaves is exactly the route smoke takes.
Closers are frequently adjusted or disconnected because a door is heavy or slams, and both are understandable responses to a real problem that leave the door non-compliant.
Where a door genuinely needs to stand open for access, hold-open devices linked to the alarm exist for that purpose. A wedge does not.
In practice
A door that closes fully and does not latch.
It swings shut from any position and stops a few millimetres short, resting against the keep.
A door that has not engaged its latch is a door a draught will open, and in a fire the pressure difference is considerably more than a draught.
It is recorded as closing properly by anybody who watches it swing and does not watch it finish.
What goes wrong in practice
- Closers disconnected or wound off so far the door no longer latches.
- Doors held open with wedges or extinguishers, which also removes the extinguisher from its point.