SUGGESTED PROJECTS AND ACTIVITIES
Complex fire-fighting systems.
1) Gas fire-fighting systems
The operating principle of inert gas fire-fighting systems lies in oxygen reduction in the flash point. It is safe to use such gas systems even in crowded places. The extinguishing agent is gas that does not conduct electricity or leave any traces after its application. This makes it possible to apply such gas systems for fire safety of expensive electronic systems, computers, unique objects, etc.
Argon fire-fighting system
Fire-fighting effect of argon gas consists in lowering the percentage of oxygen in the air in the combustion area and adjacent space from 20.9% to below 15% when the medium becomes uninflammable and the fire goes out.
Argon in a fire-fighting system is stored in modules (cylinders) in compressed state. Operating pressure is 200 bar in modules. There is a pressure relief system from 200 to 60 bar by a reducer.
This system can provide reliable protection of various objects:
- Book depositories, archives;
- Bank vaults;
- Technological rooms with high-intelligent equipment (automatic telephone exchanges, server, hardware, GSM connection rooms, television and radio broadcasting objects, etc.);
- Unique objects;
- Objects where other extinguishing substances can not be used for fire-fighting.
Moreover the advantage of this system lies in the possibility to fill cylinders on site. This is possible without dismounting any system components and at minimal downtown. As a high pressure pipeline (200-230 bar) is to be used for filling cylinders and also taking into account the fact that filling time is not so important as its efficiency back-up filling system can have a small diameter pipeline and connection point with the filling vehicle may be at the distance of 50-150 m from the cylinder storage room.
Carbon dioxide (CO2) fire-fighting system.
Carbon dioxide is used as the extinguishing agent, which reduces the percentage of oxygen in the combustion area to the level below which combustion is impossible. In addition carbon dioxide has a cooling effect on the combustion area.
Automatic CO2 fire-fighting systems are first and foremost used to protect confined spaces with high leak tightness. CO2 is also used in the open air in local fire-fighting systems providing that necessary precautions are observed. Presence of people is not allowed at the CO2 concentration, which is required for fire-fighting.
Automatic CO2 fire-fighting systems are used to fight fires of various classes and materials, including wood, fabric, paper (as a rule large CO2 amount and long presence of gas in the room are needed in these cases), inflammable gases (in this case it is necessary to make sure that explosive materials are not accumulated in the atmosphere due to the noncombustible gas discharge as a result of fire extinguishing), energized devices and electric equipment.
Gas fire-fighting system using freons
Gases NAF S-125 and HFC-227 ea (FM200) are used as extinguishing agents in fire-fighting systems. Their action is directed at decreasing oxygen concentration in the combustion area to the level below which combustion is impossible.
NAF S-125 and HFC-227 ea (FM200) can be used for extinguishing:
- Electric equipment
- Inflammable liquids and gases (equipment and pumping rooms)
- Fires in rooms where expensive devices and equipment are located (CED, operating rooms, etc)
- Fires in depositaries of works of art (museums, libraries, etc)
2) Foam fire-fighting systems
Foam fire-fighting systems suppress fire by isolating combustibles from the air (oxygen). Depending on the system type and the used foam (foam generator) it happens in several ways:
- Foam covers the burning surface of fuel suppressing fire;
- Fuel is cooled down due to water which is contained in the foam;
- Foam cover prevents the release of inflammable vapors which may mix with the air.
Low expansion water foam fire-fighting systems
The systems used for protection of inflammable liquids use synthetic low expansion foams that act very quickly spreading over the surface of the liquid on fire. Unlike ordinary foams aqueous filming foam not only forms a consistent layer of foam but also generates an aqueous film that excludes the surface of inflammable liquid from coming into contact with the air and so prevents the releasing of vapors. In the event of breakage at some point in the continuity of the film it is able to autoregenerate itself.
The basic application is sprinkler or drencher fire-fighting systems of inflammable liquids.
Medium and high expansion water foam fire-fighting systems.
High expansion foam is used to extinguish various fires inside confined spaces. Medium expansion foam is applied for fighting fires in the open air and windy spaces.
Medium expansion foam systems can be used to protect liquid and solid combustibles where an extensive coverage of spaces to protect is required, for example, the total flooding of small rooms such as cabins with engines and transformers. Medium expansion foams are also used to protect inflammable or toxic liquids where rapid saturation with the extinguishing agent is vital to prevent the propagation of vapors both for indoor and outdoor applications.
High expansion foams are also used to protect inflammable liquids and guarantee an even more coverage of the spaces to protect. They are recommended to prevent fire risks in multilevel facilities such as rack-type stores.
3) Water fire-fighting system
Due to the use of water as fire-fighting agent supplied under high pressure and obtaining of droplets of less than 100 micron in size the system offers the following advantages:
- reduction of expenses on buying reservoirs and tanks for water storage;
- lack of need to section objects to protect unlike total flooding systems;
- minimal damage caused by water fire-fighting agent, including damage caused by water as during operation of ordinary spray sprinklers and drenchers with drops of 0.4 – 2 mm in size.
Sprinklers and drenchers of water fire-fighting systems create fine mist that quickly saturates the space to be protected reducing oxygen concentration in this case and significantly increasing efficiency of water fire-fighting using minimal water quantity. When using these fire-fighting systems to fight fires the quantity of the used water is dozens of times less than in systems with ordinary sprinklers and drenchers, which makes it possible to reduce fire water stock and as a result maximally decrease damage caused by water fire-fighting.
Water mist having high heat capacity and big total active area of drops drastically decreases temperature in the combustion area putting an end to the chemical burning reaction during sprinkler and drencher operation. Quick dispersion and good cooling effect of water mist make it possible to evacuate people from the room and create conditions for special staff to work with portable water fire-fighting facilities.
Water fire-fighting systems do not use chemical additives. In this connection the system is absolutely environmentally sound.
Water fire-fighting system application:
Automatic water mist fire-fighting systems are used to extinguish solid combustibles, inflammable liquids, inflammable gases and electric installations with the voltage of up to 1000 V in various buildings, installations and rooms. It is allowed to use sprinkler and drencher system for extinguishing cables with the voltage of up to 30 000 V.
This fire-fighting system complies with international standards IMO A 800, A 913 and NFPA 75.
Standard application of the water fire-fighting system has been approved by test laboratories and numerous units have been sold as the most effective ones to protect cable tunnels of telecommunication companies, petrochemical enterprises and rail transport facilities acc. to the standard NFPA 750.
The system is applied for high efficiency protection of:
- sea vessels (engine rooms, cabins, corridors, etc.);
- storage facilities, offices, selector and server rooms, telecommunication centers;
- gas turbines, etc.
Drencher system in operation.
The offered system contains the following basic units:
- High pressure pumping unit complete with electric pumps and motor pumps as standby installed on a single support platform;
- Demineralized water reservoir of various capacities according to the required volume;
- Stainless steel AISI 316 distributing devices with the manual and electric drives to supply water to nozzles in various areas (open by AWS signal);
- Special sprinklers (the number is determined according to the project);
- Pipelines and special connectors made of stainless steel AISI 304 with the max. diameter of up to 38 mm.
Water sprinkler system to protect a petrochemical platform.