2006 New York Code - Egress From Dwellings.

 
    § 202. Egress from dwellings. 1. Nursing and convalescent homes, homes
  for  the  aged  and  boarding and nursery schools, two stories in height
  erected after July first, nineteen  hundred  fifty-seven,  child  caring
  institutions,  two  stories in height erected after July first, nineteen
  hundred sixty-two, and all dwellings three or  more  stories  in  height
  shall  have  at  least two fire-stairs. Except as otherwise specifically
  provided in subdivision four, such fire-stairs  shall  extend  from  the
  entrance  story  to the roof and be equipped with fireproof self-closing
  doors glazed with wire glass and without transoms. No windows  shall  be
  required  in such stairs, but any openings in exterior walls, except any
  window openings  facing  a  street  or  yard,  shall  be  equipped  with
  fireproof frame and sash and glazed with wire glass.
    2.  Every such fire-stair shall have an entrance on the entrance story
  from a street or an entrance at the side or rear of the dwelling from  a
  yard,  court  or  passageway  having  continuous,  safe and unobstructed
  access to a street. Every required stair and stair-landing shall  be  at
  least three feet eight inches in clear width.
    3.  There  shall be horizontal access from every apartment to at least
  two fire-stairs, at least one of which shall be within one hundred  feet
  horizontally  in the line of travel from a required means of egress from
  such apartment.
    4. A dwelling as a rule transiently or temporarily occupied, in  which
  at  least  eighty  per centum of the living rooms above the second story
  open directly upon a  public  hall  without  any  intervening  foyer  or
  private  hall,  shall  have  at least two fire-stairs accessible at each
  story from each room through a public hall. Such fire-stairs shall be so
  located that at least one fire-stair shall be not more than one  hundred
  twenty-five  feet along the line of travel from the means of egress from
  any living room. Every such fire-stair shall have a clear  width  of  at
  least  three  feet  eight  inches.  Two such fire-stairs shall be deemed
  adequate for seventy living rooms on any story.
    5. Nursing and convalescent homes, homes for the  aged,  and  boarding
  and  nursery  schools,  one  story  in height, erected after July first,
  nineteen hundred fifty-seven, and child caring institutions,  one  story
  in  height,  erected after July first, nineteen hundred sixty-two, shall
  have at least two means of egress from the dwelling accessible to  every
  apartment  providing  free  and unobstructed egress by a door opening to
  the outer air.