In certain rooms of a building, which are used for evacuation (stairwells, lift shafts), it may be necessary to install an overpressure installation. In case of fire, this system provides overpressure in the room concerned, so that smoke cannot enter this room. In this way, the escape route or attack route for the fire service remains free of smoke.
An overpressure installation can also be used in an escape tunnel. In such a tunnel, usually located next to a road or rail tunnel, an overpressure installation ensures that the tunnel remains free of smoke and heat in case of a fire and thus offers a safe escape route.
These systems are calculated according to the Royal Decree on Basic Standards.