Electromagnetic Door Holders

An electromagnetic door holder keeps a door open on a magnet and lets it go when its power is cut, usually by the fire alarm, so the door closer can shut it. It is how fire and smoke doors in corridors and stairwells can stand open in daily use and still close in a fire.

Holders mount on the wall or the floor behind the open door, and come in several voltages, so match the holder to the fire alarm system's supply. The door needs its own closer: see surface door closers. ANSI/BHMA A156.15 is the standard for closer holder release devices; each product page carries its own listing.