Section 55. Egress

1. In every transient dwelling to which this article is
  applicable there shall be from each story at least two independent means
  of egress accessible  to  each  room,  apartment  or  suite,  except  as
  otherwise  provided  in  section  sixty-three  with respect to two story
  transient dwellings.
    2. The first means of egress shall  be  an  enclosed  stair  extending
  directly  to  a  street,  or  to  a  yard, court or passageway affording
  continuous, safe and unobstructed access to a street, or by an  enclosed
  stair  leading  to  the  entrance  story,  which story shall have direct
  access to a street. That area of  the  dwelling  immediately  above  the
  street  level  and commonly known as the main floor, where the occupants
  are registered and the usual business  of  the  dwelling  is  conducted,
  shall  be  considered a part of the entrance story; and a required stair
  terminating at such main floor or  its  mezzanine  shall  be  deemed  to
  terminate  at the entrance story. An elevator or an unenclosed escalator
  shall not be acceptable as a required means of egress.
    3. The second means of egress  shall  be  by  an  additional  enclosed
  stair,  conforming to the provisions of subdivision two of this section,
  a fire-stair or an outside fire-escape. In a non-fireproof dwelling when
  it is necessary to pass through a stair enclosure which may or  may  not
  be  a required means of egress to reach a required means of egress, such
  stair enclosure and that part of the public  hall  or  corridor  leading
  thereto  from  a  room,  apartment  or  suite, shall be fire-retarded as
  provided in section fifty-two or protected by a sprinkler system;  in  a
  fireproof  dwelling  only  that  part of the hall or corridor leading to
  such stair enclosure need be so protected.
    4. Where it is impractical in such  existing  transient  dwellings  to
  provide  a  second means of egress, the department may order, in lieu of
  the second means of egress, additional alteration to the first means  of
  egress  and  to  shafts,  stairs  and  other  vertical  openings  as the
  department  may  deem  necessary  to  safeguard  the  occupants  of  the
  dwelling,  may  require  the  public halls providing access to the first
  means of egress to be equipped on each story with an automatic sprinkler
  system, and, in non-fireproof  dwellings,  may  also  require  automatic
  sprinkler heads in the stair which serves as the only means of egress.
    5. Nothing in this section shall be deemed to require the enclosure of
  a  stair  which  is ornamental provided such stair does not connect more
  than two stories.
    6. A stair, fire-stair or  fire-escape  supplementary  to  the  egress
  requirements  of  subdivisions  two, three and four of this section need
  not lead to the entrance story or to a street, or to a yard or  a  court
  which  leads  to  a  street,  provided  the means of egress therefrom is
  approved by the department.
    7. A fire-detecting system shall not be  acceptable  for  any  of  the
  requirements of this section.
    8.  In lieu of enclosing stairways as required by subdivisions two and
  three of this section, an automatic sprinkler system may be provided  on
  such stairs.
    9.  All  fire-escapes erected on or after July first, nineteen hundred
  fifty-three,  in  compliance  with  this  section,  shall  be  arranged,
  constructed  and maintained in accordance with the provisions of section
  one hundred thirty-three. Such system shall be installed,  arranged  and
  maintained  in a manner satisfactory to the department and in accordance
  with rules adopted by the commission. It shall be unlawful to remove any
  fire-escape without permission from the department.