2006 New York Code - 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.