Section 27-930. Existing standpipes

Standpipe systems existing on December
  sixth, nineteen hundred sixty-eight shall not be required to be  altered
  to conform to the provisions of this subchapter, except as follows:
    (a)  The  existing  installation  shall  meet  the  following  minimum
  requirements:
    (1) WATER SUPPLIES. There shall be a reserve of at  least  twenty-five
  hundred gallons of water in a gravity or pressure tank for exclusive use
  of  the  standpipe; or there shall be a direct connection to a city main
  meeting the requirements of section 27-945  of  article  three  of  this
  subchapter.
    (2) GRAVITY TANKS. The gravity tank or tanks shall be filled by direct
  city water connection or by an automatic fill pump at a rate of at least
  forty-five  gpm;  and  the  bottom of the tank shall be located at least
  eleven feet six inches above the highest  hose  outlet  under  the  main
  roof.
    (3)  HOSE  AND  HOSE  VALVES.  Hose  and  hose valves shall be in good
  serviceable condition. Hose valve wheel handles shall be within six feet
  six inches of the floors or stair landings or the wheel  handle  may  be
  within  two  feet  horizontally  from a stair tread and no more than six
  feet six inches vertically above the tread. Such  hose  may  be  omitted
  from  hose  racks  in existing buildings in occupancy group J-2 provided
  that the provisions of paragraph five  of  subdivision  (c)  of  section
  27-942 of article three of this subchapter are complied with.
    (4)  FIRE DEPARTMENT CONNECTIONS. There shall be a three inch by three
  inch siamese hose connection with approved caps, painted red.  The  word
  "Standpipe"  shall  be  cast in the body of the siamese connection or on
  metal plates that are secured to  the  riser  or  to  the  face  of  the
  building behind the siamese connection.
    (5)  NOZZLES.  A  five-eighths  inch  smooth  bore nozzle with two and
  one-half inch hose shall be provided where the hydrostatic  pressure  at
  the hose valve is less than ten psig.
    (6)  PROTECTION  FROM FREEZING. All parts of the standpipe system that
  are exposed to freezing  shall  be  protected  in  accordance  with  the
  requirements  of  subdivision  (a) of section 27-949 of article three of
  this subchapter.
    (7) PRESSURE  REDUCING  VALVES.  Pressure  reducing  valves  shall  be
  provided  as  required  by  section  27-944  of  article  three  of this
  subchapter.
    (8) DRIP VALVES. Drip valves shall be  provided  between  the  siamese
  connection and the check valve.
    (b) When the building requires additional standpipe protection because
  of  extension in height or in area, or the occupancy is changed to a use
  requiring additional protection, the new or altered part of  the  system
  shall comply with this subchapter.