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.