Basic countermeasures for extinguishing fires invo

Basic countermeasures for extinguishing fires caused by wet inflammables

wet inflammables can react with moisture and water to produce combustible gases and heat. Sometimes even if there is no open fire that will affect the service life of the driver, it can automatically catch fire or explode, such as metal potassium, sodium and triethyl aluminum (liquid), etc. Therefore, it is absolutely forbidden to use water, foam, acid-base fire extinguishers and other wet extinguishing agents to put out the fire when there is a certain amount of such items. This particularity of this kind of goods has brought great difficulties to its fire fighting

generally, inflammables in case of moisture are required to be stored separately in separate warehouses or in separate stacks due to the special fire-fighting measures in case of fire, but it is sometimes difficult to do so in practice, especially in the production and transportation process of cooperative partners. For example, aluminum powder is often accumulated everywhere in aluminum products factories. For the inflammables with solid package, tight seal and small quantity in case of moisture, it is allowed to store them in the same room or in the same cabinet. This has brought greater difficulties to its fire fighting work, and firefighters should be careful in the fire fighting. The following basic countermeasures are generally taken for fires involving wet inflammables

(1) first of all, it is necessary to understand the name and quantity of flammable materials when wet, whether they are mixed with other materials, the combustion range, and the way of fire spread

(2) if only a small amount (generally within 50g) meets wet inflammables, a large amount of water or foam can still be used to put out the fire, regardless of whether it is mixed with other items. When water or foam just contacts the ignition point, the fire may increase in a short time, but after a small amount of wet inflammables are burnt out, the fire will soon be extinguished or reduced

(3) if there are a large number of wet inflammables and they are not mixed with other items, it is absolutely forbidden to put out the fire with water or foam, and the wet extinguishing agents such as acid and alkali assembled by tepex and Durethan of LANXESS. Dry powder, carbon dioxide and halogenated alkanes should be used to fight against wet inflammables, and carbon dioxide and halogenated alkanes are invalid only for individual items such as metal potassium, sodium, aluminum and magnesium. Solid inflammables when wet shall be covered with cement, dry sand, dry powder, diatomite and vermiculite. Cement is a kind of fire extinguishing agent that can be easily obtained to put out the fire of solid when encountering wet inflammables. For dust in wet inflammables such as magnesium powder and aluminum powder, it is forbidden to spray pressurized extinguishing agent to prevent dust from blowing up and forming explosive mixture with air, resulting in explosion

(4) if there are many wet inflammables mixed with other goods, you should first find out which kind of goods are on fire and whether the package of wet inflammables is damaged. A small amount of water can be sprayed to the ignition point with a water switch gun to test. If there is no obvious increase in the fire, it proves that the wet goods have not caught fire and the package has not been damaged. A large amount of water or foam should be used immediately to put out the fire. After putting out the fire, immediately organize forces to evacuate the wet inflammables that have been drenched or are still in the wet area to a safe area to disperse. If the fire increases significantly after water jetting test, it proves that the inflammables have caught fire or the package has been damaged when they are wet. It is forbidden to use water, foam and acid-base fire extinguishers to put out the fire. If it is liquid, use dry powder and other extinguishing agents to put out the fire; If it is solid, it should be covered with cement, dry sand, etc; In case of fire in light metals such as potassium, sodium, aluminum and magnesium, it is best to use graphite powder, sodium chloride and special light metal extinguishing agents to put out the fire

(5) if the fire of other objects threatens more adjacent wet inflammables, cover the wet inflammables with tarpaulin or plastic film and other waterproof cloth first, and then cover it with a quilt and water. If the place where inflammables are stacked is not too high when wet, a waterproof dike can be built around it with soil. When using water or foam to put out a fire, a certain amount of strength should be reserved for the adjacent inflammables when they are wet

due to the special performance of flammable materials when wet, and the common water and foam extinguishing agent cannot be used for fire fighting, personnel engaged in the production, operation, storage, transportation and use of such materials and firefighters should know and be familiar with their product names and main hazard characteristics at ordinary times