N.Y. Multiple Dwelling Law § 54: Cellar entrance

§ 54. Cellar entrance. There shall be a direct entrance to the cellar,

or to the lowest story if there be no cellar, from the outside of every

multiple dwelling erected after April eighteenth, nineteen hundred

twenty-nine, except that in non-fireproof multiple dwellings erected

after such date which are three stories or less in height and occupied

by not more than two families on any story, any stair leading to such

cellar or lowest story may be located inside the dwelling provided it is

enclosed in fireproof walls and fireproof doors and assemblies with the

doors self-closing, at both the level of such cellar or lowest story and

that of the story above. No such outside entrance existing in any

multiple dwelling on April eighteenth, nineteen hundred twenty-nine,

shall be obstructed.