You are viewing an archived code
For the purposes of this chapter, other terms used hereinafter are hereby defined as follows:
“Air compressor.” A device for supplying air under pressure to the pressure tanks of a sprinkler system or the cushion tank of a sprinkler system, or to an inside standpipe system or to a dry pipe sprinkler system.
“Automatic sprinkler.” A sprinkler designed to open and discharge water when heated to a predetermined temperature.
“Capacity of tanks.” The capacity of gravity tanks shall be the number of U.S. gallons available to supply the sprinkler system.
“Concealed sprinkler.” A sprinkler which is recessed into the surrounding surface and provided with a cover plate.
Construction definitions.
“Obstructed construction.” Construction where beams, trusses, or other structural members impede heat flow to or water distribution from automatic sprinklers in a manner that materially affects the ability of sprinklers to control or suppress a fire.
“Unobstructed construction.” Construction where beams, trusses, or other structural members do not impede heat flow to or water distribution from automatic sprinklers in a manner that materially affects the ability of sprinklers to control or suppress a fire. Unobstructed construction may have horizontal structural members that are not solid, with openings that are at least 70 percent of the vertical side area and the depth of the member does not exceed the least dimension of the opening.
“Fire area.” The largest floor area, up to a maximum of 12,000 square feet, enclosed within the exterior walls of a building, if not divided into independent areas by fire walls, or the floor area of any such independent area, if so divided.
“Fire pump.” A device used for supplying water to a sprinkler system at the pressure required by the system.
“Fire pump, automatically controlled.” A fire pump which starts automatically when the pressure in the system drops to a predetermined point and stops automatically when the pressure in the system rises to a predetermined point.
“Gravity tank.” A wooden or metal elevated container holding water to supply a sprinkler system at gravity pressure.
“Hydraulically calculated system.” An automatic sprinkler system in which pipe sizes are selected on a pressure loss basis to provide a prescribed minimum water discharge density in gallons per minute per square foot over a specified area.
“N.F.P.A.” or “NFPA”. The National Fire Protection Association.
“Open sprinkler.” A sprinkler in which the discharge orifice is open at all times.
“Pressure maintenance pump.” A small pump under automatic control used to maintain pressure on the system to avoid frequent operation of the system fire pump.
“Pressure tank.” A tank holding water pressurized with air to supply a sprinkler system at a pressure greater than that due to gravity.
“Siamese connection.” A two or other multiple inlet fitting installed on the outside of a building and connected to the system main of a sprinkler system for the use of the fire department only, to supply water to the system.
“Sprinkler.” The outlet used in a sprinkler system to discharge water onto a fire.
Sprinkler system types:
(1) Wet pipe system – A system employing automatic sprinklers attached to a piping system containing water and connected to a water supply so that water discharges immediately from sprinklers opened by heat from fire.
(2) Dry pipe system – A system employing automatic sprinklers attached to a piping system containing air under pressure, the release of which from the opening of sprinklers permits the water pressure to open a valve known as a “dry pipe valve”. The water then flows into the piping system and out the opened sprinklers.
(3) Pre-action system – A system employing automatic sprinklers attached to a piping system containing air that may or may not be under pressure, with a detection system installed in the same area as the sprinklers. Actuation of the detection system opens a valve known as the pre-action valve which permits water to flow into the sprinkler piping system and to be discharged from any sprinkler that may be open.
(4) Deluge system – A system employing open sprinklers attached to a piping system connected to a water supply through a valve known as a deluge valve which is opened by the operation of a detection system installed in the same areas as the sprinkles. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.
(5) Combination dry pipe and pre-action sprinkler system – A sprinkler system employing automatic sprinklers attached to a piping system containing air under pressure with a detection system installed in the same areas as the sprinklers; operation of the detection system actuates tripping devices which open “dry pipe valves” simultaneously and without loss of air pressure in the system. Operation of the detection system also opens air exhaust valves at the end of the feed main which facilitates the filling of the system with water which usually precedes the opening of sprinklers. The detection system also serves as an automatic fire alarm system.
“Supervised.” When applied to an automatic sprinkler system, shall mean equipped with electrical devices which indicate the position of the valves controlling sources of water for the system to an office located on the premises which is continuously attended or to a listed central station alarm service.
“Tank heater.” A device for heating the water in a gravity tank, pressure tank, or tank riser to prevent the water in these portions of a sprinkler system from freezing.
“Water supply piping in a sprinkler system.” The piping from the sources of supply to the sprinkler heads. The different sections of the water supply piping are:
(1) Branch line. A horizontal pipe which conveys the water to the sprinkler heads.
(2) Cross main. The pipe supplying the branch lines, either directly or through risers.
(3) Feed mains. The pipes supplying risers and cross mains.
(4) Pump suction. A pipe which conveys the water from the city main or other sources of supply to the fire pump.
(5) System riser. A vertical pipe which conveys the water supply to feed mains or cross mains.
(6) Tank riser. The pipe which conveys the water from a gravity or pressure tank to the system main or sprinkler system.
“Water supply, two source.” A two source water supply shall mean two independent supplies of water from a combination of a city water main, gravity tank, or reservoir or two independently controlled city water mains.
(Prior code § 91-2; Amend Coun. J. 10-30-96, p. 31216, § 1; Amend Coun. J. 5-18-16, p. 24131, § 116)