6. 1.2 B fire: refers to liquid fire and fusible solid fire. Such as gasoline, kerosene, crude oil, methanol, ethanol, asphalt, paraffin, etc.
6. 1.3℃ fire: refers to natural gas methane ethane, propane, ammonia fire and other gas fires.
Class D fire: refers to metal fire, such as potassium, sodium, magnesium, titanium, lithium, aluminum, magnesium and alloy fire. 6.2. 1 Material combustion must meet three conditions: combustible, combustion-supporting material and ignition source.
Combustible: it is the main body of combustion, such as charcoal, cotton and gasoline.
(2) Combustion-supporting substances: participate in combustion, react chemically with main substances, and accelerate the combustion process, such as air.
(3) Ignition source: substances or methods that make combustible substances reach the ignition point, such as lightning and fire.
6.2.2 Ignition source type: A naked flame and high-temperature surface B friction impact C electric spark D electrostatic e lightning 6.3. 1 Initial stage: after general solid combustible materials are ignited and burned, the combustion area is not large, the flame is not high, the radiation heat is not strong, and the smoke and flow are slow within 15 minutes. The burning speed is not fast, which is the best time to put out the fire. More than 70% were released by people present.
6.3.2 Development stage: the initial fire was not found and put out in time. With the extension of combustion time, the temperature rises, the surrounding combustible materials are heated rapidly, the gas convection is enhanced, the combustion speed is accelerated, and the area is rapidly expanded, forming a development stage.
This is the key stage of fire fighting, so we must make great efforts and take correct measures to control the development of fire and further put out the fire.
6.3.3 Fierce stage: the fire is not well controlled in the development stage. With the continuous extension of combustion time, the speed is accelerating, and the product expands rapidly, the temperature rises sharply, and the airflow reaches the fastest, which is the most difficult stage in fire extinguishing.
6.3.4 Descending fire extinguishing stage: At the stage when the fire is about to burn out or be extinguished, we should be vigilant to prevent re-ignition. 6.4. 1 is a measure to prevent the ignition of the fire source in advance before the fire occurs, and it is the most fundamental fire prevention measure. This measure is to effectively and properly manage the substances with fire danger and ignition sources with ignition energy so that they will not cause fire.
6.4.2 Three understandings:
(1) understand the post fire risk,
(2) understand the preventive measures,
③ Know how to put out the fire.
6.4.3 Three meetings:
I'll call the police,
(2) can use fire fighting equipment,
(2) Put out the first fire. 6.5. 1 The principle of saving lives first and concentrating strength.
6.5.2 The principle of control before elimination.
6.5.3 The principle of focusing first, then general. 6.6. 1 isolation method: isolate or remove combustible materials at and around the fire source. If there is no combustible substance, the combustion will stop.
6.6.2 Asphyxiation method: it is to prevent air from flowing into the combustion zone or dilute the air with incombustible substances, so that combustible substances can not get enough oxygen and be put out. For example, use carbon dioxide, nitrogen and steam to put out the fire, and directly cover the surface of combustible substances with incombustible or flame-retardant substances to isolate the air and stop the combustion.
6.6.3 Cooling method: Spray the fire extinguishing agent directly on the burning object to make the temperature of the burning object lower than the ignition point and stop burning, or spray the fire extinguishing agent on the object close to the fire source to prevent it from being threatened by the radiant heat of the flame and avoid forming a new ignition point. The main extinguishing agents are water and carbon dioxide.
6.6.4 Suppression method: The extinguishing agent participates in the chain reaction of combustion, so that the free radicals generated in the combustion process disappear and form stable molecules or low-activity free radicals, thus stopping the combustion reaction. This method must have enough extinguishing agent to participate and interrupt the combustion reaction, otherwise it will not play a role in inhibition. 6.7. 1 Common classes:
(1) Fire hydrant, hose, water gun and water.
② Carbon dioxide fire extinguisher.
6.7.2 Composition and principle of fire fighting equipment.
① Composition: It consists of nozzles and pipes.
② Principle: By reducing the oxygen content in the air, it can't reach the concentration supporting combustion. Carbon dioxide in the air reaches more than 15%, which makes people suffocate and die; When it reaches 30%-35%, the combustion of general substances will gradually suffocate; When it reaches 43.6%, it can inhibit the explosion of flammable gases such as gasoline vapor.
6.7.3 Fire extinguishing methods:
(1) in case of fire, open the head valve of the steel cylinder through the manual valve, and stretch out the hose to spray the carbon dioxide fire extinguisher to the ignition point.
③ Other categories: foam, dry powder fire extinguishers, 12 1 1 fire extinguishers, etc.
Smoking is a common hobby of people. In daily life, the fire caused by smoking is quite serious, which is one of the important contents of fire safety work.
(4) Although cigarette butts are a small heat source, they can cause many substances to burn. The surface temperature of cigarette end is 200-300 degrees, the center temperature is 700-800 degrees, and the burning time of cigarette is 4- 15 minutes. If the remaining cigarette butts are 1/4, they can burn for 1-4 minutes. 130 degrees, cloth 200 degrees, loose 250 degrees, under the condition of natural ventilation, cigarette butts are still in wood chips with a depth of 5 cm, smoldering after 15-90 minutes, and if there is a flame, cigarette butts are thrown into wood shavings with a depth of 5- 10 cm, with a 75% chance. 6.8. 1 "invisible killer" in fire: poisonous gas.
The combustion of most substances produces many gases, such as carbon monoxide, carbon dioxide, sulfur dioxide and so on. Many of them are toxic gases. Visible solid or liquid particles suspended in the atmosphere produced by combustion or pyrolysis are always called smoke. According to statistics, about 80% of deaths in fires are caused by inhaling toxic gases. The smoke produced by fire contains a lot of toxic components, which are harmful to human body to varying degrees. For example, carbon dioxide, one of the main combustion products, can reach 15% in some fires.
Its main physiological function is to stimulate people's respiratory center, which leads to shortness of breath and increased smoke inhalation, thus causing headaches, unconsciousness and other symptoms. Carbon monoxide is one of the main combustion products that cause death in fire, and its toxicity lies in its high affinity for hemoglobin in blood, which is 250 times higher than that of oxygen. Therefore, it will hinder the transmission of oxygen in human blood, causing headache, collapse, unconsciousness and muscle adjustment disorder.
When the content of carbon monoxide produced by fire in the air reaches 0. 1%, it can make people feel headache and vomit within 60 minutes; When it reaches 0.5%, there is a danger of death; When it reaches 1%, people will lose consciousness after breathing several times, which can lead to poisoning death within one or two minutes. 199365438+In February, a fire broke out in a wholly Taiwan-funded enterprise in Mawei Town, Fuzhou City, and most of more than 60 working girls were killed by fire after being poisoned. In April of the same year, a fire broke out in Tangshan Linxi Department Store, killing 79 people. After forensic identification, except one person who jumped to his death, all the other victims were suffocated and burned by toxic gases such as carbon monoxide. In May of the same year, a fire broke out in the bath center on the second floor of Miao Ling Hotel in Fengtai District, Beijing, and all seven migrant workers were poisoned by smoke. There are countless such fire cases, which fully shows that poisonous gas is the "invisible killer" in the fire and has swallowed thousands of lives. However, in April 1996, a fire broke out in Swan Hotel in Harbin, Heilongjiang Province, and 10 people were killed. Among the victims were China and North Korea, and six Japanese were also threatened with death in the fire, but they managed to escape with rich escape experience and survived.
Because when they entered the hotel, they had already found out the surrounding environment, and when the fire broke out, they could accurately judge the safety exits and evacuation passages, thus successfully escaping.
In all kinds of modern buildings, whether hotels, restaurants, public places of entertainment, family homes, etc. Most people only pay attention to the luxury of decoration, but ignore that many decorative materials are flammable, such as artificial floor, plastic wallpaper, chemical fiber floor, etc. These chemical decorative materials will produce a lot of toxic gases when burning, so in the event of a fire, people who escape are in danger of being suffocated by toxic gases.
Preventive measures:
① Understand the environment: pay attention to the location of safety exits, shelters, alarms and fire extinguishers.
(2) Articles that can be used as escape equipment form habits.
③ Smoke prevention: Once the fire is confirmed, smoke prevention measures should be taken regardless of whether there is smoke nearby. The common measure is to cover your nose and mouth with dry towels and wet towels.
4 Try to escape: to stabilize emotions, overcome panic, and calmly choose ways to escape. Don't waste time wearing valuables and don't run away from narrow corners. Call the police quickly: people often say that time is life. When a fire is found, you should first call the "1 19" fire alarm telephone to explain the fire location, unit, combustible materials, burning degree, etc. Firefighters will immediately rush to the scene to rescue after receiving the alarm, which can not only minimize the fire loss, but also win more people trapped by the fire to get the help of firefighters and reduce casualties.
Find an exit and use the building's own refuge facilities to save yourself: when a fire breaks out, don't follow others nervously or blindly, but use your brain to remember the direction of the exit carefully. This is a "green passage" to escape from the door of death. In the fire, most people were very scared, at a loss, crowded and trampled on each other, and blindly walked into a "dead end", thus causing many deaths and injuries. Of course, people who have a little sense of escape will pay attention to the specific locations of fire exits, safety exits and emergency exits once they enter the hotel.
So in the event of a fire, you will have a well-thought-out plan and try to escape, not afraid of danger. If the smoke at the fire scene is large, it is difficult to see or judge the exact location of the fire escape, then the fire escape can be found by the direction of the smoke at the fire scene.
Give up money to save your life: among the victims of fire accidents, some people lost the chance to escape because of greed. Some people want to grab more valuable items and then flee the scene. Some people have already fled the scene and come back to get things, but they don't know that even for a minute, sometimes it is only one step away from the door of death. 1999 in a fire in Jiangxi province, two female migrant workers failed to escape just to get their wallets back to their rooms and were left in their rooms forever. Therefore, after the fire, you should leave the scene quickly to avoid greed for money.
Emergency help, using the natural conditions of the building itself and its vicinity to save yourself: if you can't escape through the safety exit and evacuation passage, you can open the window, throw things, wave or shout loudly, knock things, etc. And send out a distress signal, thus attracting the attention of firefighters outside the window and fighting for rescue time.
When you can't break through, move to the bathroom and toilet, crawl forward, drain water, lie on the ground and prevent smoke. Because the fire will produce a lot of toxic gas, and the smoke is lighter than air, and the smoke concentration near the ground is not high, so when you escape from the fire scene, you should wet the towel (mask, napkin cloth, etc.). ), cover your nose and mouth and crawl forward. Especially when crossing the smoke area, try to hold your breath and move forward quickly to reduce the entry of toxic gases into the body.
Self-rescue by tying rope: If there is a life-saving rope at the scene after the fire, one end of the life-saving rope can be fixed on the heating pipe, the foot of the bed or other heavy objects, then the window is opened, and the other end slides vertically along the lower part of the window to escape. If there is no lifeline at the scene, you can tear sheets, curtains, quilts, etc. Block it, twist it into a strong rope, and wet it with water as a lifeline. When using this method to escape, it should be noted that the fixed end of the lifeline must be tied firmly, and carefully check whether the rope is safe to prevent it from loosening or breaking after loading.
Cautiously jump off a building: under the condition of not jumping to death, use some quilts and other things to jump to the carport, grass or tree downstairs to slow down the impact.