Extinguishing systems fixed

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. 

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...

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

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. 

Fixed installations, such as water spray systems, halon systems, sprinkler systems, carbon dioxide extinguishing systems, explosion suppression systems, and other fire protection installations are often provided with flow and trouble detection switches connected to transmitters. A signal indicating the condition of the system should be sent to the attended location(s). 

NFPA 11—Standard for Low-Fxpansion Foam NFPA 11A—Standard for Medium- and High-Expansion Foam Systems NFPA 12—Standard on Carbon Dioxide Extinguishing Systems NFPA 12A—Standard on Halon 1301 Eire Extinguishing Systems NFPA 13—Standard for the Installation of Sprinkler Systems NFPA 15—Standard for Water Spray fixed Systems for Fire Protection NFPA 25—Standard for the Inspection, Testingand Maintenance of Water-Based Fire Protection Systems... 

Fundamental to the use of fixed water-spray systems and other water-based extinguishing systems is a water supply that is adequate in terms of capacity, pressurization, and reliability. The capacity available may come from bodies of water, domestic supplies, and/or tank storage. A system s adequacy must be judged on the basis of its projected maximum flows, the duration of its flows, and the volumes necessary to meet industrial needs. The latter is relevant in cases where there is no dedicated supply. 

The active methods of fire extinguishing use the forced delivery of extinguishing media and materials to the area of fire origin. In some cases, for the small cells nitrogen delivery is envisaged. In the cells with non-radioactive sodium transportable fire-extinguishers are used. Also, fixed powder fire extinguishing systems are provided. 

When a fixed system is activated, a major portion of the rapidly expanding gas wiU become carbon dioxide vapor, while the remainder will become very fine particles of dry ice. There will also be condensed water vapor due to the cooling action of the expanding gas. As a result, visibility may be limited and individuals trapped in an area may have difficulty finding their way out. An area equipped with an automatic carbon dioxide extinguishing system should be posted with warning signs, such as ... 

For a fixed extinguishing system, is a sign posted warning of... 

Fires in or on offshore wind turbines and substations 33 CER Chapter 1, Subchapter N, Part 145, Fire-Fighting Equipment NEPA, Codes and Standards (e.g., NFPA 12—Standard on Carbon Dioxide Extinguishing Systems) NFPA 850 RP for Fire Protection for Electric Generating Plants DNV-OS-J201(2009)—Offshore Substations for Wind Farms (Section 6) Safety of Life at Sea Provisions GL Wind Technical Note Certification of Fire Protection Systems for Wind Turbines, Rev. 2,2009 ed. BS EN 13565-2 2009—Fixed Firefighting Systems... 

Category Fixed Extinguishing Systems - General (1910.160) The system... 

Who Train employees who will inspect, maintain, operate, or repair fixed extinguishing systems... 

Special Hazards. There are many tools and materials used in a facility. Where they can increase the frequency or severity of a loss, they are known as special hazards. In an HPR facility, these hazards require fixed local protection. This can be in the form of additional sprinklers, segregation, or a fixed automatic extinguishing system. These devices can catch a fire in its incipient stage and prevent the involvement of the building protection. 

Smoke detectors are not designed for the hostile atmosphere of a wet station where they are needed. The construction of conventional smoke and heat detectors will not stand up. A Southern California company developed a photoelectric detector that is mounted outside the plemun and searches for flame through a plastic window. These units did not have a stand-alone listing or approval but are Factory Mutual approved as part of a fixed extinguishing system. These are no longer manufactured. 

Sheltered Combustible Areas. Many tools will have sheltered areas of combustible construction handling flammable and combustible liquids. These areas should be protected with automatic sprinklers or a fixed extinguishing system. 

Fixed extinguishing systems are seeing increased service. Halon systems previously used for protection of wet benches are no longer available. These systems could protect either the face or the sump of the wet bench. Another common use of Halon was below the raised floor in older fabs. The Halon systems are replaced with FM-200 watermist and CO2... 

The fire scenario selected to be analyzed deals with the fire fighting means designated to be applied in a reference NPP once a fire occurs for any reason. One major assumption is the failure of the automatic actuation of the fixed fire extinguishing system in the compartment where the fire is supposed to start. This implies that fire fighting mainly depends on the operability of the fire detection and darm system, the performance of human actions as well as on the operability of active fire barrier elements (e.g. fire dampers and fire doors) and of the fire extinguishing systems which can be manually actuated. 

If equipment and procedures work as intended, fire fighting is a rather short process, because the compartment where the fire is assumed to occur is equipped with a fixed fire extinguishing system which suppresses the fire with a sufficiently large amount of water after actuation by the fire detection and alarm system. However, one major assumption of the andysis presented here was the failure of the automatic actuation of the fixed fire extinguishing system. This implies that the fire has to be extinguished by manual fire fighting means performed by the plant personnel in charge. 

Are fixed extinguishing systems used on specific fire hazards ... 

Are fixed extinguishing systems inspected annually by a qualified person ... 

Fixed extinguishing systems, water spray and foam... 

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