The characteristics of the initial fire: the initial fire stage is called the initial fire within a few minutes after the object catches fire, and has the characteristics of smaller burning area, slower flue gas flow speed, less flame radiant heat, and slower temperature rise of surrounding objects and building structures. In the initial stage of fire, it is easy to control or extinguish the fire. In general, fire extinguishers and indoor hydrants can be used to extinguish initial fires.
The principle of early fire fighting is:
(1) control first, then put out the fire;
(2) focus first, then general;
(3) preventing poisoning and suffocation;
(4) listen to the command, don't panic;
According to the principle of material combustion, there are four methods to put out the initial fire: isolation method, suffocation method, cooling method and resistance method.
First, cooling method: according to the burning of combustible objects, certain temperature conditions must be reached, and fire extinguishers are used to spray directly on the burning objects to reduce the temperature of the burning substances to below the ignition point, when the objects stop burning; Water can be used for cooling and extinguishing fires, which is a common method for extinguishing fires. When a common substance catches fire, water can be used to cool and extinguish the fire. Water can also be used to cool building components, production devices or containers to prevent them from being deformed or exploded by heat.
II. Asphyxiation Method: According to the condition that sufficient air (oxygen) is needed when combustible objects are burned, air can be prevented from flowing into the combustion area, or non-combustible substances can be used to dilute the oxygen content in the air, so that the combustion substances can be extinguished due to cutting off the combustion support of oxygen. The so-called smothering method is to cut off the air supply of combustion products. It is suitable for fighting fires in enclosed spaces, production equipment and containers.
Three, isolation method: according to the conditions of burning must have combustible objects, the burning objects and nearby combustible materials will be isolated or scattered, so that the burning objects will stop burning. It is a common fire extinguishing method. Fire extinguisher is used to isolate combustible from air and heat, foam produced by foam extinguisher fire extinguishing is used to cover the surface of burning liquid or solid, while cooling, combustible is separated from flame and air, etc., all belong to isolated fire extinguishing method. If combustible materials are isolated from ignition sources or air, the combustion reaction will automatically stop.
Four, suppression method: use fire extinguisher to interfere with and inhibit the chain reaction of combustion, so that free radicals generated in the combustion process disappear to form stable molecules or low-activity free radicals, thus achieving the effect of extinguishing fire.
You can put out the fire at the initial stage and avoid causing great disaster.
1. When a fire is found, you should shout for help and seek help from the people around you. At the same time, you should call fire alarm quickly.
2. Before firefighters arrive at the scene, they should try to put out the fire and save themselves. Local materials can be used to extinguish the fire. It is best to have a fire extinguisher, and sand, blankets, quilts and other items can also be used to cover the fire.
Fire 3. Don't open doors and windows casually when the fire is on, so as not to spread the fire due to air convection.
4. When someone is under siege, first save people.
5. When the oil pan catches fire, cover the pan cover quickly to extinguish the fire. Never use water to put out the fire. If the oil fire is spilled on the stove or the ground, portable fire extinguisher can be used to extinguish the fire, or wet quilt, wet blanket, etc. can be used to cover the fire and extinguish the fire immediately.
6. When the gas cooker is on fire, if liquefied gas is used, cover the cylinder guardrail with towels, rags, etc. quickly, cover the cover with clothes, quilts, etc. after soaking in water to extinguish the fire, and quickly close the main valve. If pipeline gas is used, the two keys of closing the valve and extinguishing the fire should also be grasped to prevent the fire from spreading.
7. When household appliances catch fire, cut off the power supply before putting out the fire.