And the type of device to force the door shut itself off and must be turned on at any time. Door or exit to the ladder must not be owner ณ๊ห or barrier edge.
And to install devices that force the doors shut by themselves and must be opened with ease all the time. Have no natural outlet to the stairway door or on or rim.
And have to stick device that forced the door closed, and must be opened conveniently at any time. The door or exit to the ladder must not ธรณ? Or edge.