A lift’s main brake and gearbox, 24 Sep 2011. When the lift breaks down, if there are passengers inside then this needs to be clamped shut as it is by default closed. The clamping tool can just about be seen on top of the orange grille. Doing this releases the brake so the lift can descend by gravity until it gets to to the closes floor, where the passengers can be released by manually opening the lift doors.