Section 51. Construction of public buildings

1.  (a) In addition to any
  other requirements respecting the construction of a public building  and
  facilities    thereof,    the    new    construction,    reconstruction,
  rehabilitation, alteration or improvement  of  all  such  buildings  and
  facilities  shall  conform  to  the  requirements  of the state building
  construction code relating to facilities for the physically handicapped,
  except work already completed, work  in  progress,  or  work  for  which
  schematic  designs have been approved by the effective date of this act.
  This section shall not be effective if its provisions  will  impair  the
  structural stability of the public building or its facilities.
    *   (b)   This   section   shall  not  apply  to  the  reconstruction,
  rehabilitation, alteration or improvement of rapid transit terminals  or
  stations in New York city, which shall be governed by subdivision two of
  this section.
    * 2. With respect to the reconstruction, rehabilitation, alteration or
  improvement  of  any  rapid  transit terminal or station of the New York
  city transit authority or of the Staten Island rapid  transit  operating
  authority,  the  obligations  of such authorities for complying with the
  requirements  of  the  state  building  construction  code  relating  to
  facilities  for  individuals  with  disabilities shall be limited to its
  compliance  with  the  requirements  of  subdivision  three  of  section
  fifteen-b of the transportation law.
    *  NB  The  provisions  of par (b) of sub. 1 and sub. 2 are subject to
  expiration on July 26, 2020 if the Metropolitan Transportation Authority
  does not comply with the provisions of  sub.  3  of  sec.  15-b  of  the
  transportation law.