258 - Public halls.

§ 258. Public halls. 1. Every public hall shall be everywhere at least  three feet in clear width.    2.  Except  as  herein provided, every public hall shall be completely  enclosed with fireproof floor, ceiling and  walls,  and  separated  from  every  stair  by  fireproof partitions or walls, and all doors and their  assemblies  opening  therefrom  shall  be  fireproof,  with  the   doors  self-closing  and  without transoms. In a dwelling three stories or less  in height occupied by not more than four families on each story, or in a  permanently occupied dwelling or any section thereof two stories or less  in height, any such hall which furnishes access to only one  stair  need  not  be separated from such stair by any partition or door and the walls  of a public hall may be fire-retarded and the  floors  may  be  provided  with three inches or more of incombustible materials between the beams.    3. Except in dwellings three stories or less in height and occupied by  two  families  or  less  on every story, every public hall shall have at  least one window opening directly upon a street or upon a lawful yard or  court. There shall be such a window at the end of such hall and at right  angles to its length, with an additional window in each  forty  feet  of  hall  or  fraction  thereof  beyond  the  first sixty feet from such end  window; or the hall shall  have  one  window  opening  directly  upon  a  street, yard or court, in every forty feet of the length of such hall or  fraction thereof measured from one end of the hall. Any part of a public  hall  that  is  shut  off  from any other part of such hall by a door or  doors shall be deemed a separate hall.    4. The foregoing provisions of this section with  regard  to  lighting  and  ventilation  shall  not  apply  to a vestibule or other public hall  which serves as a means of access from one or  more  apartments  opening  thereon  to a fire-stair meeting the requirements of section two hundred  two if such vestibule or  public  hall  is  lighted  and  ventilated  as  required by sections one hundred nine and two hundred seven.