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.[2] When the fire alarm is triggered it cuts power to the electromagnetic hold-open device allowing the doors to close. These hold-open devices can be separate from the door closer or part of its design.door closer is designed to assist a person using a doorway allowing them to smoothly and effectively open and shut a door without the need to physically return the door to the framed opening themselves. When properly adjusted, there will be a slight "back-pressure", giving the user some feedback as to the weight of the door, followed by a smooth transition as the door glides easily open in front of the user. Upon reaching the maximum set opening of the door, the closer takes full control dampening the opening forces, quietly and gently closing the door until the door is back in the frame, latched and ready for the next user.