Hold-open mechanisms single leaf
A hold-open mechanism is part of a hold-open system. The interplay of a trigger mechanism, a fire alarm system and a power supply makes the hold-open system.
In the event of a fire, fire and smoke doors that are being held open are closed automatically. In Germany, hold-open systems on fire and smoke doors require a general construction permit from the Deutsche Institut für Bautechnik (DIBt), Berlin.