Extinguishing a fire is an extremely dangerous and stressful business. However, when fires occur in the cold season, this process also becomes extremely difficult, with increased consumption of both human and technical resources.
The case of fire fighting in the cold season is also complicated by the increasing challenges of combat crews. In winter, the occurrence of fires is associated with a large number of heating devices in houses and apartments, working stoves, which are a source of increased fire hazard. Often faulty are electrical appliances, wiring and sockets. Shorting with a large number of heating elements leads to the appearance of foci of combustion, which must be extinguished in conditions of negative ambient temperature.
Difficulties in fighting fires
Fire extinguishing at low temperatures in accordance with the standards of the Federal Fire Service is considered to be elimination of fire when air is cooled below -10 degrees Celsius. In the work of the fire brigade at temperatures below -10 degrees, methods of eliminating fires are used as when working in the winter. When extinguishing fires at low temperatures, you need to carefully monitor the standards for the use of special fire extinguishing agents, since among them there are those that are not intended for use at low temperatures. They may not work during the liquidation of a fire or impede the operation of fire equipment.
Complications of fire extinguishing
Winter is no less difficult to extinguish a fire than summer. Firefighters may experience the following problems during operation:
- Source of open flame and spark. With wind and low humidity, sparks can be picked up by the wind and cause a fire in nearby buildings.
- Raising the temperature of objects exposed to fire and the surrounding atmosphere. Excessive heat from an open flame significantly complicates the work of the fire brigade, increasing the extinction time.
- Emission of smoke and toxic substances into the air during a fire. Smoke and harmful substances released by heating plastic and other materials reduce visibility in a fire, impede breathing and are poisonous factors. Moreover, most often citizens suffer from combustion products, losing consciousness and not responding to the call of rescuers. This makes the process of saving people in a fire difficult.
- Drop in oxygen level.
- Destruction of building structures. Partial or complete collapse of parts of the building poses a great threat to both the victims of the fire and the team of firefighters.
- Fire extinguishing work at negative temperatures is complicated by delays, malfunctions of the fire equipment or its complete failure. The most frequent breakdowns and malfunctions are the hoses of fire fighting equipment and their branching points. Special clothing fire brigade at low temperatures is covered with ice, freezes, making it difficult for the specialist to move. Such a hardening of the firefighter's suit poses serious health problems due to hypothermia and possible frostbite of the body.
The work of firefighters at low temperatures has increased tension, as there are frequent malfunctions with pump systems, breakouts of fire extinguishing hoses, malfunctions in the water supply system, icing in the process of eliminating the fire.
The main task of extinguishing a fire is to carry out a set of works aimed at saving living things, material objects and eliminating fires.
During the fire extinguishing process, advanced techniques and means are used to eliminate fires. The authors of the methods present the advanced parameters of technical means for extinguishing fires, special schemes for the use of means for eliminating fires, the rules for taking and supplying water for eliminating a fire, methods for pumping it out and delivering water for eliminating combustion through a tank truck.
Fire fighting tactics
Modern sources of literature on extinguishing fires at low temperatures give definitions of the capabilities of fire fighting equipment and the human factor. To optimize the work of fire crews, several types of fire fighting tactics have been developed:
- on the combat deployment of fire equipment;
- on the supply of fire extinguishing means;
- to save citizens;
- opening and demolition of building structures;
- when using personal protective equipment.
Specialists working in the fire brigade use techniques for calculating the forces and equipment of units that may be required during the elimination of fires. Firefighters also plan to extinguish various types of materials, including toxic ones. Calculation workers are developing methods for using new fire extinguishing means, and are conducting combat training exercises.
Extinguishing Extinguishing Water in Cold Weather
The organization of fire extinguishing at low temperatures is hampered by environmental conditions. It is difficult to use water from open nature due to freezing of open water bodies. When used in the process of extinguishing a fire at low temperatures, water from urban water supply systems, the temperature of the incoming water is 1 degree heat. Such indicators in conditions of negative air temperature lead to the appearance of an ice build-up on the water supply hoses. In severe frosts, the water in the arms of the fire fighting equipment may freeze, and the system will stop supplying water to the fire extinguishing object.
In addition to the work of equipment for eliminating combustion, the peculiarities of extinguishing fires at low temperatures include its effect on the crew of the team. Such weather conditions create the possibility of frostbite on the skin of firefighters. Frostbite of the extremities leads to delayed actions, which affects the efficiency of the elimination of burning. This applies to extinguishing fires at temperatures below -30 degrees Celsius.
Features of the elimination of fires in winter
To optimize fire fighting methods at low temperatures, standards have been developed. They are approved by the Ministry of Civil Defense and Emergencies. The rules for extinguishing fires at low temperatures include the following:
- If necessary, water intake in open reservoirs at negative air temperatures should be carried out pumping water from low depths of water sources. This is due to the temperature of the water at the bottom: the farther from the surface, the higher the temperature.
- Before attaching the fire fighting hose, before starting the pump, open the valve of the pump nozzle and put the pump on the spout. This will make sure that the pump system is working properly. Then it is necessary to increase the speed of the pump and, if the operation goes smoothly, close the valve of the nozzle without a hose line and open the valve in the pump line with the hose attached.
- In the pipeline of fire fighting equipment, completely drain the water and suck out the water remaining in the vacuum line.
- If the fire engine is not used for some time, then its engine should be warmed up to prevent the system from freezing.
- If windy weather is observed during extinguishing a fire, then the connecting parts of the hoses should be sprinkled with snow, since with a strong wind the possibility of glaciation increases, and the snow provides additional protection from the cold wind.
Rules for laying hose lines
If when extinguishing fires at low temperatures, laying of lines from hoses is used, then the following conditions must be observed:
- When laying in work, use sleeves with rubber in the composition and large diameter.
- In case of street fires, if possible, do not place branches on the sleeves. This can lead to stagnation and freezing of water at branch points.
- Lay the lines straight, avoiding creases and bends, in order to avoid stagnation of water and its freezing in these places.
- If breakdown and leakage are detected in the hose line, it should be immediately sealed with a hose clip.
- If the hose line or water supply pump is allowed to glaze, warming should be done by pouring hot water into the tank of a working car.
- If branching of sleeves is used to extinguish a fire, then the branching divergence should be established inside buildings. If this is not possible, then they should be insulated, since this place is a weak link in establishing negative temperatures. It is there that the occurrence of leakage or the freezing of water to extinguish is most likely.
- At low temperatures, it is recommended that additional dry hose lines be laid to ensure the smooth operation of the fire fighting team.
Fire extinguishing tactics at low temperatures are aimed at preventing freezing of fire extinguishing hoses, ensuring a sufficient amount of water. In this regard, the fire brigade uses hoses and barrels with a large flow of water when leaving for a fire in the open air at low temperature. At the same time, they carefully monitor that the trunks are not blocked, the water flows evenly and in full.
According to the rules of extinguishing fires at low temperatures, the fire brigade must prepare a place for heating members of the fire brigade and rescued citizens. This is done to prevent frostbite of the limbs. When extinguishing a fire at low temperatures, according to the instructions, the fire brigade should carry an additional supply of combat clothing in order to eliminate the fire in case of wetting of the main set, in order to prevent overcooling of firefighters.
To ensure uninterrupted water supply at low temperatures, firefighters and equipment should not be shut down to avoid freezing of the supply system.
A feature of extinguishing a fire at low temperatures is considered to include the ban on the placement of hose lines on the fire escape. This is due to the possibility of icing up the stairs, which can become the main means of saving people in case of fire. To avoid water entering the fire escape, it is forbidden by the rules to place equipment hoses directly on them, as well as in the vicinity of them.
Fire fighting methods in winter
When extinguishing fires at low temperatures, it is believed that one of several working methods should be followed to minimize production costs and optimize the work of the fire fighting team. They are developed and approved by a special commission. Fire extinguishing methods at low temperatures mean the following:
- If icing occurs on the hose of fire equipment or hose fittings, water is heated into the system, heated to a temperature of over +120 degrees Celsius. In this case, additional heating of the water is required based on the need to eliminate icing of the fire extinguishing system, without losing temperature indicators.
- To extinguish a fire at low temperatures, the water is heated no lower than up to +170 degrees Celsius. Water of this temperature, when it enters the main stream, is distributed along the entire length of the sleeve, thereby increasing the temperature in the entire system, allowing the equipment not to freeze and to extinguish a fire at least +120 degrees.
- When extinguishing a fire in the conditions of steady negative temperatures, a chemical reagent in the form of foam can also be used. This product is similar to a glacier compound used on roads to eliminate glaze and reduce the possibility of ice formation. The basis of such a foam is a solution of magnesium chloride in high concentration, a foaming agent that can withstand temperatures up to -30 degrees Celsius, and a foam stabilizer.
During fire extinguishing at low temperatures, the authors of special techniques recommend that in severe frosts and winds, in order to prevent freezing of the hose for water supply, do not reduce the pressure even when it is temporarily not needed directly on their extinguishing territory. When reducing the source of ignition at the position occupied by the firefighter responsible for holding the barrel for water supply, the flow of the supply fluid must be directed into the window or doorway. However, this should be done in such a way that the water flowing during the withdrawal of the trunk through the opening does not fall on the hoses of the fire system, roads near the fire extinguishing site, nearby houses and buildings, and fire escapes.
Idle water conditions for fire extinguishing
When extinguishing a fire at low temperatures, it is believed that one of the main difficulties is the correct direction of the idle water flow. When spilling the hose without the need to eliminate the fire, the fireman in charge of the barrel should pay special attention, as it is necessary to choose a direction of water supply that does not lead to damage.
Damage possible when extinguishing a fire at a low temperature, if the direction of water supply is incorrectly selected, this may be:
- When extinguishing the barrel to stationary and mobile ladders, there is a breakdown of equipment for raising and lowering them, as well as bruises and serious damage resulting from the fall of fire brigade employees.
- When directed to firefighting workers, it is getting wet and icing on working clothes, getting frostbite on skin areas, hypothermia of the body and, as a result, serious diseases that affect the health status of the brigade workers.
- If the direction of the trunk is the roof, the coating will freeze. With the growth of the ice layer on the roof of the building, cases of sliding of fire brigade employees on its surface become more frequent and, as a result, this ends with a fall from the roof and injury.
The main rule when working on extinguishing fires at low temperatures is the continuous supply of water in the fire extinguishing system and the hoses of fire equipment. When increasing its length or replacing a sleeve that has failed, it is necessary to reduce water pressure in order to avoid freezing, but not to stop its flow.
Correct shutdown of the fire brigade
When the fire is localized, and new fires are not observed, the working team must collect the equipment used in the fire. For the correct completion of the work of the brigade in the fire extinguishing equipment, do not stop the water supply, but lower the pressure. During a decrease in water pressure, workers disconnect the sleeve and, starting from the trunk, pour out the water remaining after the fire. After draining all the water from the hose, the firefighter quickly rolls up the equipment until it is iced and frozen. If you hesitate, the sleeve will freeze and become not flexible, which will not only complicate the work of laying equipment, but can also cause its breakdown.
Actions of the commander in the brigade
To ensure the efficiency of equipment cleaning, the commander of the fire department during fire extinguishing at low temperatures can provide an additional number of firefighters. This is aimed at increasing the speed of winding hose lines. With insufficient collection or discharge of not all water from the hoses and branches, icing of part of the fire equipment, creases and scraps can occur, which leads to poor condition of the hoses and often makes them unsuitable for further use.