Fire extinguishing systems

Fire-detection devices such as flame-sensing or ioni2ation-interference types operate much more rapidly than sprinkler heads and are used extensively both as alarms and to activate fixed fire-extinguishing systems. 

Halon 1301 Fire Extinguishing Systems, NFPA 12A, paragraph 1-5.3, National Fire Protection Association, Boston, Mass., 1992. 

Table 6.13 General requirements for fixed fire-extinguishing systems (Activation may be automatic by a detection system, or manual)...

Table 12.15 General requirements for fixed fire extinguishing system...

Gaseous fire extinguishing systems precautions for toxic and asphyxiating hazards (withdrawn) General fire precautions aboard ships being fitted out or under repair Eire precautions m pressurized workings Access to road tankers... 

Fire extinguishing systems can include foam, carbon dioxide and dry chemical. Wetting agents and high e.xpansion foam have been used in some plant protection systems. All fire extinguishing systems should be evaluated for the potential health risks as well as overall effectiveness before incorporation into a plant. 

Some alloys are softer than the component metals. The presence of big bismuth atoms helps to soften a metal and lower its melting point, much as melons would destabilize a stack of oranges because they just do not fit together well. A low-melting-point alloy of lead, tin, and bismuth is employed to control water sprinklers used in certain fire-extinguishing systems. The heat of the fire melts the alloy, which activates the sprinklers before the fire can spread. 

GS16 Gaseous fire extinguishing systems precautions for toxic and asphyxiating hazards. 

Sprinklers and fire protection systems are required by NFPA Codes, but are often dependent on the overall size of the facility and quantity of stored flammable/combustible material. The wisest course of action is to provide heat and smoke detectors in each laboratory and provide a sprinkler system at least in the hallways. Each laboratory should have at least one ABC portable fire extinguisher. Computers have become more important to laboratories than ever. Halon fire extinguishing systems are available which are nondestructive to both electronic equipment and human life. These should be employed for fire protection. 

Activate fixed fire extinguishing systems or vapor dispersion mechanisms (i.e., water sprays). 

Clean agent systems can also be used for explosion prevention and suppression where flammable materials are confined. Clean agent fire extinguishing systems are used primarily to protect hazards that are in enclosures or equipment enclosures. Some typical hazards that could be protected by clean agents are ... 

Where a detection system is part of an automatic, fixed fire extinguishing system, complete compatibility between the systems is essential. 

It is important to select detection devices that are appropriate for the type of fire most likely to occur. Failure to do so will result in either a very slow response or the possibility of a large number of spurious alarms. The latter should be particularly avoided where the detection system is used to activate a fixed fire extinguishing system. 

Clean agent fire extinguishing systems are used primarily to protect enclosures. Clean agents can be used to protect enclosures containing ... 

NFPA 750—Standard on Water Mist Fire Protection System NFPA 2001 —Standard on Clean Agent Fire Extinguishing Systems... 

An automatic carbon dioxide fire-extinguishing system. 

The facility where the computer equipment resides must be equipped with the appropriate fire-extinguishing systems or equipment. 

Halons are used in automatic fire-extinguishing systems, such as those located in flammable solvent storage areas, and in specialty fire extinguishers, such as those on aircraft. It has proven difficult to find substitutes for halons that have the same excellent performance characteristics. 

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