A door closer is defined as any mechanical device that closes a door in a controlled manner, preventing it from slamming, in general after someone opens it,[1] or after it was automatically opened. The force used to open the door is stored in some type of spring and when released this energy is then utilised to return the door to a closed position. Door closers can be linked to a building’s fire alarm system. Where doors need to be held open for the majority of the time they are held back with an electromagnetic device.
