N.Y. Multiple Dwelling Law § 105: Separation and ventilation of stairs

§ 105. Separation and ventilation of stairs. 1. In a dwelling in which

one or more passenger elevators are maintained and operated opening upon

a public hall at every story, all stairs, fire-stairs and fire-towers

shall be completely separated from one another and from every elevator

shaft by fireproof walls. They shall be constructed of fireproof

material throughout and shall contain no wood or other inflammable

material of any kind, except that handrails of hardwood may be provided.

2. Access to stairs, fire-stairs and fire-tower balconies from any

public vestibule or other public hall shall be through fireproof doors

and assemblies, with the doors self-closing and at least three feet

wide, or through pairs of such doors at least four feet wide, containing

in either case a fixed sash glazed with wire glass at least three

hundred sixty square inches in area.

3. Every stair hall shall be ventilated by a window, or by movable

louvres in the skylight having an opening of at least one hundred

forty-four square inches, or by an opening of at least one hundred

forty-four square inches near the top of the stair shaft and

communicating directly with the outer air. If a window is provided which

does not open upon a street or yard, it shall be fireproof and glazed

with wire glass of good quality and have no pane more than three hundred

sixty square inches in area.