Decontamination is the main measure to eliminate the toxic hazards of infected and contaminated areas. Therefore, decontamination of hazardous chemical disasters is a very important and indispensable step.

First, physical decontamination

The main use of natural conditions such as ventilation, sun and rain, so that the poison evaporates itself to lose and be hydrolyzed, so that poisons gradually reduce the toxicity or be gradually destroyed and lose its toxicity, soaked in water boiled boiling, or directly with large amounts of water to flush the infected body. The cotton, gauze, etc. may be impregnated with solvents such as gasoline, kerosene, and alcohol to scrub off toxic substances on the surface of the infected body, and methods for sealing and burying or removing toxic substances may be used for the source of liquid and solid pollution. But burying must add a lot of bleach. The advantage of physical decontamination is that it is easy to handle and easy to implement.

Second, chemical decontamination

Chemical decontamination is the use of decontamination agents to produce chemical reactions with toxic or toxic substances, resulting in non-toxic or very toxic products, it has a thorough disinfection of environmental protection better features, but pay attention to decontamination agents and poisons Whether or not the chemical reaction produces new toxic substances, prevents the recurrence of reactions, and the use of equipment and equipment in the chemical decontamination of poisoning accidents consumes a large amount of decontamination chemicals and has a high cost. In the actual decontamination of chemical and physical methods are generally used at the same time, in order to make the decontamination agent can effectively play a role in chemical emergencies, decontamination agent selection must meet the "decontamination speed, decontamination effect is thorough , Decontaminants are used less, the price is cheaper, and the decontamination agent itself does not have the decontamination principle of the corrosive damage to personnel equipment." Chemical decontamination methods include neutralization, redox, and catalytic methods.

1. Neutralization is the use of acid-base neutralization to eliminate poisons. Strong acid (sulfuric acid H2SO4 , hydrochloric acid HCl , nitric acid HNO3 ) can be used when 5-10% of sodium hydroxide, sodium bicarbonate, calcium hydroxide, etc. are used as neutralizing decontamination agent, ammonia can also be used, but ammonia itself is irritant. Use concentration control when using. Conversely, if a large amount of alkaline substances are leaked (such as ammonia leakage), neutralize with acidic substances, but it is also necessary to control the concentration of the decontaminant solution, otherwise it will cause harm, and after the completion of neutralization decontamination, there is still need for residues. Rinse with plenty of water.

2. Oxidation and reduction method: The redox reaction occurs between the decontaminant and the poison, and the toxic and long-lasting oily liquid poisons are decontaminated. Such decontaminants such as bleaching powder (the active ingredient is calcium hypochlorite), triads Two (its nature is similar to the bleaching powder), but the bleach contains less calcium hypochlorite, many impurities, low chlorine, disinfection performance is not as three in two, but it is easy to manufacture, low prices. If the chlorine cylinder leaks, the leakage cylinder can be placed in a lime water tank. The chlorine gas reacts to generate calcium chloride, which can eliminate chlorine harm to personnel and environmental pollution. Burning can also be used to destroy the toxicity of poisons. This method can be used for facilities or items that are of little value or can be used after fire, but may cause air pollution in the vicinity and downwind direction due to the volatilization of poisons. Therefore, we must pay attention to proper personal protection .

3 , catalytic method: the use of catalysts in the presence of poisons to accelerate the change into non-toxic or low toxic chemical reaction. Some toxic pesticides (including more toxic phosphorus pesticides), the hydrolysate is non-toxic, but the reaction rate is very slow, adding some catalysts can promote its hydrolysis, the use of pesticides plus alkaline substances can be catalytic hydrolysis. Therefore, alkali or alkaline solution can be used to remove pesticide-induced poisons.

Third, common poisons and neutralizers

Fourth, the object of decontamination

After the occurrence of a chemical accident, the most effective way to eliminate the impact of the disaster is decontamination. The scope of decontamination includes the comprehensive decontamination of contaminated objects when the rescue operations permit, and the execution of all rescued personnel from the contaminated areas. Comprehensive decontamination, comprehensive decontamination and decontamination of all vehicles and equipment and equipment out of the contaminated area, and thorough decontamination of the entire accident area. The chemical warfare suits and battle suits and the used anti-virus facilities, testing instruments and equipment of the participating personnel shall be decontaminated.

Intoxication personnel and equipment decontamination

Decontamination must be performed in strict accordance with the decontamination procedures and standards. The test must meet the relevant standards set by the state, and the methods of decontamination include the establishment of a fixed decontamination station and the implementation of motorized decontamination. The fixed decontamination stations are generally set up at non-polluted sites that facilitate the arrival of contaminated objects, and are located as close as possible to the water source. They are mainly used when the number of large-scale decontamination tasks is heavy and the motor decontamination is mainly used for those who need emergency treatment. method.

Collective decontamination system, decontamination station

Such as the use of decontamination tents , to be responsible for the task of extinguishing the fire and be seriously contaminated personnel to carry out timely decontamination, it has the advantage of flexibility and convenience, generally available a lot of clean hot water, commonly used public decontamination tents , personal anti- corruption tents for combatants Professional decontamination equipment such as high pressure washers are used to decontaminate personnel.

Inflatable decontamination spray device decontamination tent

If a serious chemical accident occurs, ordinary clean water cannot achieve the effect of decontamination. Disinfectant can be added for decontamination. If there is no disinfectant, it can be scrubbed with soap. The place for decontamination must be closed. Yes, there are special persons responsible for testing the arrangements for the demolition of personnel in accordance with the order of the wounded, women and children, the elderly and young adults.

The object of decontamination is vehicle equipment for intoxication, including clothing and testing equipment for the combatants. The decontamination of the vehicle can be done with high pressure washers, high pressure water guns and other facilities. We carry out top-down, inside-out, and front-to-back order cleaning.

No professional equipment can also use water or disinfectant scrubbing soaking, scour, sunlight and other methods. Decontamination personnel and equipment must be tested before leaving. Otherwise, the infected object needs to be decontaminated until it passes the test.

Detoxification of sources and contaminated areas

After a hazardous chemical disaster occurs, it is necessary to eliminate dangerous substances in a timely manner. It is necessary not only to promptly organize rescue forces to implement leakage or reversed tank transfer on the leaked sites, but also to implement decontamination of hazardous sources and contaminated areas. Detoxification can be carried out only after the leakage of toxic substances is controlled.

The selection of decontamination methods is based on the nature of the poison and the site conditions. Decontamination of the accident site is sometimes repeated several times, and the decontamination operation can be stopped only when it reaches the disinfection standard.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.