Section 27-944. Pressure reducing valves

(a) When the normal hydrostatic
  pressure at a two and one-half inch hose outlet valve exceeds fifty-five
  psig, each valve shall be equipped  with  an  adjustable  type  pressure
  reducer  so  that  the  pressure  on the downstream side will not exceed
  fifty psig when the discharge is at the rate of two hundred gpm  from  a
  one inch orifice nozzle attached to one hundred feet of two and one-half
  inch unlined hose.
    (b)  At  one  and  one-half  inch hose stations, an adjustable type of
  pressure reducer shall be provided on each hose outlet valve  where  the
  hydrostatic  pressure  exceeds eighty-five psig and shall be so adjusted
  that the pressure on the downstream side will  not  exceed  eighty  psig
  when  seventy  gpm  is  discharged  from  a one-half inch orifice nozzle
  attached to the length of hose to be provided at the hose station.
    (c) The pressure reducing valve shall be permanently marked  with  the
  address  of  the  premises  in  which it is installed and with the floor
  location and the setting for the location at which it is to be used.