Fire escapes — Commercial buildings; access to escapes; hallway and stairway lights

It shall be the duty of the owner entitled to the beneficial use, rental, or control of any building already erected, or which may hereafter be erected, in which 10 or more persons are employed at the same time in any of the stories above the 2nd story, except 3-story buildings used exclusively as stores or for office purposes, and having at least 2 stairways from the ground floor each 3 or more feet wide and separated from each other by a distance of at least 30 feet, from 1 of which stairways shall be easy access to the roof, to provide and cause to be erected and affixed thereto a sufficient number of the aforesaid fire escapes, the location and number of the same to be determined by the Mayor of the District of Columbia, and to keep the hallways and stairways in every such building as is used and occupied at night properly lighted, to the satisfaction of the Mayor, from sunset to sunrise.