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Fire extinguishing of the vulnerable or valuable equipments, live (electrical) equipments and special hazard equipments require special attention. Gas fire extinguishing equipments are the best choice for the protection of computer halls, servers, telecommunication equipments, control centres, electric switch-boards as well as for protection of the varnishing chambers, turbines, archives, museums, etc. By the fire in its initial phase of propagation detection and by extinguishing agent discharge in a couple of seconds the damage incurred is minimal one. Imperative condition of the effective solution of the protection is the correct selection of system, its liable design and implementation, it means the optimum gas selection, reaching of the correct extinguishing gas concentration and it’s keeping during the requested period of time.
Chemical gases
Chemical gases utilization in comparison with natural gases represents the minimum spatial demand for hardware device and it does not require the implementation of overpressure shutters in the building constructions of protected space. FM-200® (also known under the name HFC-227ea) colourless gas with no malodour and it is not conductive one. Extinguishing effect is based on the chemical interaction and physical heat absorption. It is there suitable for spatial fire extinguishing where Halon 1301 was applied in the past. FM-200 extinguishes the fire fast and clean, it enters the space within 10 seconds since the fire extinguishing process initiation. By the correct extinguishing concentration utilizing even the health of persons present in protected space is not endangered. NAF S125® (HFC-125) has the similar properties and utilization possibilities like
FM-200.
Natural gases
Natural gases are commonly present in the atmosphere and therefore they have no impact on the global warming and ozone layer. They are of versatile utilization for all types of fire, including the deep smouldering fire. Their fire extinguishing effect is based on the oxygen concentration reduction in protected space below the level which enables no burning anymore (less than 15%). Installing of the overpressure shutter in the protected space building construction is necessary.
IG01 – argon is chemically inert, not electrically conductive and colourless, with no taste and odour gas. It is suitable for the protection of spaces where are people present and for the rooms with electric and electronic equipments
IG55 is a 50% / 50% mixture of argon and nitrogen.
IG100 – nitrogen is gas commonly present in the atmosphere and it has the most universal utilization – from the protection of manned spaces over the electric equipments securing up to extinguishing of the flammable liquids.
CO2 is the colourless gas with no odour, it is not electrically conductive. It extinguishes the fire in space by the means of oxygen concentration in space decreasing and as a side effect it cools the space down. Inhaling of this gas even with low concentration can cause an asphyxia carbonica (oxygen in blood deficiency). This must be taken into the account by design. CO2 is effectively utilized for over 50 years and it is first of all suitable for unmanned spaces such as transformer stations, electric equipments, backup centres, archives, etc. It is heavier than air, it creates thick aerosol cloud and therefore it can be used for the local fire extinguishing too.
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