Aerosol fire fighting by Ankos 66 ltd - Bulgaria
The search of new fire fighting technologies has demanded to use the existing fundamental discoveries and developments in the sphere of volume fire fighting.
The most effective volume fire extinguishing agents are the oxides of alkaline metals in the substance of fines solid aerosols, which have extensive surface and which are produced during the burning of solid fuel and pyrotechnical compounds. These compounds can burn independently without air access. This substance has a very high extinguishing ability for the hydrocarbons flames excelling the extinguishing gases.
The volume aerosol fire extinguishing system is based on the inhibiting of chain reactions which occur in the zone of burning by the fines solid particles which are produced in the result of aerosol producing cartridge. These particles can stay analepsis during 30-40 minutes.
When the extinguishing concentration of aerosol is achieved in the room, the flaming combustion stops, the heat release decreases and the temperature of the gas environment in the room decreases. During 10-15 minutes after termination of generators operation the fire extinguishing concentration of aerosol persists. This makes the repeated ignition impossible.
The aerosol producing agents can be formed in the solid cartridges of different shape. Production of aerosol generators is based on these aerosol producing cartridges.
Aerosol fire extinguishing systems are used for liquidation of fires in different buildings and constructions. The necessity of use and limits are determined by the standards, rules and other official documents.
Also aerosol fire fighting systems can provide the fire safety in conditions which are not acceptable for traditional fire fighting technologies: in the transport, electrical equipment, unheated premises which have wide temperature range, explosive premises, in conditions of lack of water.
The list of buildings and premises which are to be protected with automatic aerosol fire extinguishing systems is given in table A of rules SP5.V130.2009 "Fire protection systems. Automatic fire alarm and fire fighting systems. Norm and rules of design."
In current conditions of legislative control of fire safety, estimation of fire risks and stimulation of fire insurance, the owner of buildings and premises is interested in the choice of effective, reliable and economic fire extinguishing systems.
The most demanded are solid aerosol forming compositions, the extinguishing ability of which exceeds all fire fighting methods which are used for volume fire extinguishing. This is demonstrated in the table given below.
The analysis of the technical and economical characteristics shows that most of substances which are traditionally used for volume fire fighting, have lower extinguishing ability than the aerosol, and fire extinguishing systems which use such substances are bulky, difficult in operation and expensive.
Aerosol fire extinguishing is profitable. The price for all components is lower, and besides the aerosol fire extinguishing does not require additional operational costs. For example, the gaseous fire extinguishing system which has been installed in the cable spaces of Lefortovo road tunnel, costs 5.3 times more expensive than the analogue aerosol system.
Halocarbons which contain chlorine and bromine, are destructive for the ozone layer. Their production and application are suspended. During generator operation the content of oxygen in the atmosphere is practically not reduced. The fire extinguishing aerosol is not toxic, which allows to save humans lives with no harm to their health. Besides aerosol does not have any negative effect to the equipment and other property.
Since aerosol forming compound which is used in generators is solid during storage and maintenance, generators do not require recharge and are always ready for operation. Generators of fire extinguishing aerosol provide fire safety in conditions when other methods cannot be used (water-scarce areas, unheated premises, transport, alive electrical equipment, etc.)
Aerosol fire extinguishing has significant advantage over other fire fighting methods: it's ecologically safe, nontoxic (which reduce the hazard to human's health) and can be easily cleaned.
The use of aerosol fire extinguishing systems allows the owner of the object to protect his property from the fire and make significant savings.
Characteristics of fire extinguishing methods |
Halocarbon |
Nitrogen N2 |
CO2 |
Powder |
AFC |
Extinguishing concentration (for organic inflammable materials), kg/m3 |
0,22-0,37 |
0,6-0,8 |
0,6-0,7 |
0,5-0,7 |
0,04-0,06 |
Operating temperature, С |
-35...+50 |
-50...+50 |
-35...+50 |
-50...+50 |
+-60 |
Volume of hermetic space protected by 1 kg of extinguishing compound, m3 |
2,7-4,5 |
1,25-1,7 |
1,4-1,7 |
1,4-2,0 |
17-25 |
Automatic fire extinguishing
The fire has always been one of the most frightening and dangerous elements. That is why there have been developed a lot of technologies and devices which reduce the possibility of fire to minimum.
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