What are the basic fire extinguishing methods in hotel fire protection knowledge?

(1) Cooling to extinguish fire

Once combustibles reach the ignition point, they will burn or continue to burn. Under certain conditions, when the temperature of combustibles is lowered below the ignition point, combustion will stop. For flammable solids, cooling them below their ignition point; for flammable liquids, cooling them below their flash point may cause the combustion reaction to cease. Extinguishing fires caused by general solid materials with water is mainly achieved through cooling. Water has a large specific heat capacity and high heat of vaporization, and has good cooling performance. During the process of extinguishing a fire with water, the water absorbs a large amount of heat, rapidly reducing the temperature of the burning material, extinguishing the flame, controlling the intensity of the fire, and ending the fire. The water mist of the water spray fire extinguishing system has a small droplet diameter, a large specific surface area, and a large contact range with the air. It can easily absorb the heat of the hot air flow and can also quickly reduce the temperature, and the effect is more obvious.

(2) Isolation fire extinguishing

Among the three elements of combustion, combustibles are the main factor in combustion. By isolating combustibles from oxygen and flame, combustion can be stopped and fires extinguished. For example, an automatic water-foam combined system sprays foam while spraying water. The foam covers the surface of the burning liquid or solid. While exerting a cooling effect, it separates the combustibles from the air, thereby extinguishing the fire. For another example, when extinguishing a flammable liquid or combustible gas fire, quickly close the valve of the pipeline transporting flammable liquid or combustible gas, cut off the pipeline of flammable liquid or combustible gas flowing to the fire area, and at the same time open the flammable liquid or combustible gas to the safe area. Valves to transfer flammable liquids and flammable gases in containers that have burned or are about to burn or are threatened by fire.

(3) Suffocation and fire extinguishing

The combustion of combustibles is an oxidation process, which needs to be above the minimum oxygen concentration. If it is below the minimum oxygen concentration, combustion cannot proceed and the fire will be extinguished. . Generally, when the oxygen concentration is lower than 15%, combustion cannot be maintained. In the fire place, non-combustible gases, such as carbon dioxide, nitrogen, steam, etc., can be injected to reduce the oxygen concentration in the space, thereby suffocating the fire. In addition, when the water spray fire extinguishing system is working, the sprayed water droplets absorb the heat of the hot air flow and convert it into steam. When the water vapor concentration in the air reaches 35%, the combustion stops. This is also an application for suffocation fire extinguishing.

(4) Chemical suppression and fire extinguishing

Since flaming combustion proceeds through a chain reaction, if the production of free radicals can be effectively inhibited or the concentration of free radicals in the flame can be reduced, This will stop burning. Common fire extinguishing agents for chemical suppression fire extinguishing include dry powder fire extinguishing agent and heptafluoropropane fire extinguishing agent. Chemical suppression fire extinguishing speed is fast, and when used properly, it can effectively extinguish initial fires and reduce casualties and property losses. This method is effective for flaming fires, but for deep fires due to poor permeability, the fire extinguishing effect is not ideal. When conditions permit, the use of chemical suppression fire extinguishing agents in combination with water, foam and other fire extinguishing agents will achieve significant results.