N.Y. Multiple Residence Law § 28: Stairs and entrance halls

§ 28. Stairs and entrance halls. In every such dwelling three stories

or more in height the wood wainscoting and other combustible materials

on the wall and ceiling surfaces in all halls shall be removed and

replaced with incombustible or other fire-resistive materials. In lieu

of such removal, a sprinkler system may be installed in such halls or

such wainscoting and the combustible surfaces may be treated or covered

in a manner satisfactory to the department with a surface fire-retardant

approved by the department. In such a dwelling, however, any entrance

door and every door opening into any entrance hall, stair hall, or other

public hall connected therewith, shall be self-closing. Every interior

sash, or opening other than a door, in the walls or partitions of such

halls and every window therein not opening to the outer air shall be

sealed with fire-resistive materials.