Section 27-963. Direct connection of sprinklers to the public water system

Direct connection of sprinklers to a city water main shall be acceptable
  as  an  automatic  water  supply,  provided  the  main  is  capable   of
  maintaining  a  pressure  of  at  least  fifteen  psig at the top of the
  highest sprinkler riser, with five hundred gpm of water flowing  from  a
  two  and one-half inch hydrant outlet located at the street level within
  two hundred fifty feet of the building. The hydrant test shall  be  made
  between  the  hours of eight a.m. and five p.m. on a working day. If the
  pressure found in this test is insufficient to  comply  with  the  above
  requirement,  a  minimum  of  twelve  psig  at  the  top  of the highest
  sprinkler riser shall be acceptable, provided that  all  piping  in  the
  affected area and supply piping thereto that is four inches and under is
  increased one pipe size above those sizes required by reference standard
  RS 17-2, RS 17-2A or RS 17-2B, as applicable. In addition to the fifteen
  psig  or  twelve  psig requirements, the following requirements shall be
  met.
    (a) The size of each connection shall be as large as that of the  main
  riser  and,  except in sprinkler systems in multiple dwellings, shall be
  at least three inches and shall be controlled by an  accessible  shutoff
  valve.
    (b) The service pipe shall be flushed out thoroughly before connecting
  to  the  sprinkler system. A flow sufficient to produce a water velocity
  of at least five fps shall be used.
    (c) Each service shall be equipped, under the sidewalk, with a control
  valve in a flush sidewalk box located within two feet of the front  wall
  of  the  building  or  street  line  as  required  by  the department of
  environmental protection. The location of the  control  valve  shall  be
  indicated  by  a  sign  placed  on  the  structure directly opposite the
  sidewalk flush box, and such sign shall have a white background with one
  inch red letters  reading:  "Automatic  Sprinkler  Shutoff  Valve...Feet
  Opposite  This  Sign." Alternatively, brass, bronze, or other metal sign
  with one inch letters, raised or counter-sunk one-eighth of an inch  may
  be used.
    (d)  The  plans  submitted  in  connection with the permit application
  shall be accompanied by a statement from the bureau of water  supply  of
  the  department  of environmental protection, stating the size of street
  main or mains, distance to and size of mains from which it or  they  are
  fed,  the location of control valves, the static pressure on the hydrant
  nearest the premises, and the residual pressure in the street main taken
  on a hydrant near the premises when the flow from the nearest hydrant is
  equal to the flow required to meet the requirements of this  section.  A
  letter   from   the   bureau  of  water  supply  of  the  department  of
  environmental protection estimating available flow and residual pressure
  shall be acceptable to the borough superintendent when  a  hydrant  test
  cannot be conducted.