Sprinkler system deluge

Deluge sprinkler system open sprinklers and an empty line that is connected to a water supply line through a valve that is opened upon detection of heat or a flammable material. 

A deluge sprinkler system is a sprinkler system designed to NFPA 13 with open sprinkler heads. A water spray system is hydraulically designed with open spray heads to protect a specific hazard. Water spray systems are discussed in Section 7.4.8. 

After 11 30 a.m. Automatic deluge sprinkler system found to be severely damaged by fire/explosions and is now valved into OFF position. Three fixed fire monitors directed on fire at full flow. Two hose streams from hydrants directed on fire also. 

Active fire protection systems (e.g. smoke or heat detectors, deluge sprinkler systems or foam systems). 

There are four basic types of sprinkler systems wet pipes, dry pipes, pre-action, and deluge. These are described in the following sections. 

A fire department connection with check valve should be provided on all sprinkler systems in buildings excluding deluge systems. A hydrant should be located within 50 ft (15 m) of the fire department connection. 

In open process structures or grade level process areas, deluge or water spray nozzles should be of the open type to ensure rapid actuation and to combat the effects of wind. For enclosed structures, closed head sprinkler systems can be used. 

Within 20 to 35 minutes after the heater was fired, a fire-water sprinkler system tripped. A heater flame failure alarm occurred a short time later. Witnesses stated flames were over 50-ft. (15 m) high in approximately five seconds after the tube ruptured. The fire damages were the greatest on the third and fourth levels of the process unit as 10- to 12-mph winds carried flames and destructive heat into the unit. There was an excellent response by the emergency squad with eight hose lines reinforcing the fixed fire-water deluge systems. 

Deluge Foam-Water Sprinkler Systems NFPA 25... 

Deluge systems—are similar to very large sprinkler systems and are used to extinguish fires and suppress toxic releases. Deluge systems are expensive and are used primarily on processes concerned with extremely hazardous chemicals, such hydrofluoric acid. Most are activated automatically. 

The system comprises a series of water mains, usually overhead, to which sprinkler heads are fitted at intervals. As heat from the fire reaches them individual sprinkler heads operate at predetermined temperatures releasing a deluge of water over the fire below. The advantages of sprinkler systems are, that as only the heads in the vicinity of the fire operate, water damage is reduced to a minimum, they are automatic in operation, they are not impaired by smoke or fumes and are not hindered by the blockage of access routes. 

There are numerous types of sprinkler systems. They can be wet pipe, preaction, dry pipe, deluge or antifreeze. 

Like the dry sprinkler system, the deluge system has several disadvantages ... 

The preaction system. In libraries, museums, or other locations where special contents may be housed, the preaction sprinkler system must be used. Any operation of the sprinkler system in the absence of fire would be devastating to the building contents. Most fire safety professionals identify two events that must take place in order to activate the system. First, the heat of a fire will melt the fusible link in the sealed sprinkler heads. Second, a detector must open the deluge valve to admit the water. In the absence of either of these two events, the sprinkler system will not function. The biggest disadvantage of this system is the cost. However, when contents of great value must be protected, the expense of a preaction system may not be restrictive. 

If an ethyl ether fire occurs, carbon dioxide, carbon tetrachloride, and dry chemical fire extinguishers meeting National Eire Prevention Association Code 1 and 2 requirements may be used successhiUy (23). Water may also be effectively appHed (see Plant safety). Hose streams played into open tanks of burning ethyl ether serve only to scatter the Hquid and spread the fire. However, ether fires may be extinguished by a high pressure water spray that cools the burning surface and smothers the fire. Automatic sprinklers and deluge systems are also effective. 

The third line includes fixed fire protection systems (sprinklers, water sprays, or deluge systems, monitor guns, etc.), dikes, designed drainage systems, and other systems that control or iiiitigaic ha. ardous releases. 

National Fire Protection Association (NFPA) NFPA 16, Deluge Foam-Water Sprinkler and Foam-Water Spray Systems. NFPA, Quincy, MA, 1991. 

Materials or containers stacked or placed so that they block the effective discharge of sprinkler or deluge fire protection systems or fire monitor nozzles. 

Measures to reduce the impact of fire include active and passive systems. Active systems include automatic sprinkler, water deluge, water mist, gaseous agent, dry chemical, foam, and standpipe handle systems. Passive protection is provided by fire resistive construction, including spray-applied or cementitious fireproofing of steel, concrete/masonry construction, and water-filled steel columns. Chapter 7 provides details on the design of fire protection systems. 

Containment systems are also used in conjunction with an automatic foam-water sprinkler/deluge system where rapid fire extinguishment is expected. 

Deluge protection can be applied over the entire hazard area with open sprinkler heads located at various floor levels or fixed water spray systems can be applied specifically on the equipment to be protected. Specific water spray application is preferred because it provides better equipment cooling and reduces the water wasted due to wind and fire draft. 

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