Emergency treatment of chemical leakage accidents

1.Alarm

It is necessary and mandatory that all leaks must be reported immediately. Timely transmission of accident information and notification of accident status are key links to reduce accident losses to the lowest level. Whenever a leak is discovered - whether it is a large or small leak, it must be reported. When a sudden release of hazardous chemicals causes serious injury, fire or explosion, call the fire department first. Let a professional spill team or fire department contain and clean up. If an incident requires emergency evacuation, the alarm must be sounded and the building must be vacated. Just waiting for emergency services or outside assistance can turn a minor incident into a catastrophe, so everyone on scene should take the correct actions according to the emergency plan.

2. Emergency evacuation

Establish a warning area After an accident occurs, a warning area should be established according to the spread of chemical leakage or the scope of flame radiation heat, and traffic control should be implemented on the main roads leading to the accident site. Warning signs should be set up at the boundaries of the warning area and there should be special personnel on guard. Except for firefighting and emergency response personnel, other personnel are prohibited from entering the warning area. When the leaked chemicals are flammable, fire should be strictly prohibited in the area. Quickly evacuate personnel in the warning area who are not related to the emergency response of the accident to reduce unnecessary casualties. Attention should be paid to emergency evacuation: If the accident substance is toxic, personal protective equipment needs to be worn and corresponding monitoring measures should be taken; it should be moved upwind; a special person should be designated to guide and escort the evacuated personnel to a safe area, and a sentry post should be set up on the evacuation or evacuation route to indicate the direction; do not stay in low-lying areas; check whether anyone is left in the contaminated area and the fire area. In order to ensure the smooth progress of evacuation, each workshop should have at least two unobstructed emergency exits with obvious signs.

3. First aid on site

In any emergency, saving lives is the highest priority. At the scene of the accident, chemicals may cause harm to the human body: poisoning, suffocation, frostbite, chemical burns, burns, etc. When performing first aid, both the patient and the rescuer need to take appropriate protection. When someone is injured by chemicals at the scene, the following treatment should be carried out immediately: quickly remove the patient from the scene to a place with fresh air; give oxygen when breathing is difficult; immediately perform artificial respiration when breathing stops; immediately perform cardiac massage in case of cardiac arrest; when the skin is contaminated, take off the contaminated clothes and rinse with running water. The rinse should be timely, thorough, and repeated many times; when the head and face are burned, pay attention to the cleaning of the eyes, ears, nose, and mouth; when people are frostbitten, they should be rewarmed quickly. The rewarming method is to soak in 40°C-42°C constant temperature hot water to raise the temperature to near normal; when gently massaging the frostbitten area, be careful not to scratch the skin of the injured area to prevent infection; when a person is burned, the patient's clothes should be taken off quickly, rinsed with water to cool down, and the wound surface should be covered with a clean cloth to avoid contamination of the wound surface; do not break the blisters at will. When the patient is thirsty, he can drink water or salty drinks in moderation; for those who take it orally, symptomatic treatment can be given according to the nature of the material; after on-site treatment, he should be escorted to the hospital for treatment quickly.

4. Leakage handling and control

If the leakage of flammable chemicals is not handled properly, it may turn into a fire or explosion accident at any time, and fire and explosion accidents are often expanded due to the spread of leakage accidents. Therefore, to successfully control chemical leaks, it is necessary to plan in advance and have a full understanding of the chemical properties and reaction characteristics of the chemicals.

Leakage treatment precautions:

When entering the leakage site for treatment, the following points should be noted: personnel entering the site must be equipped with necessary personal protective equipment; if the leaked chemical is flammable and explosive, fire should be strictly prohibited; it is strictly forbidden to act alone during emergency treatment, and there must be a guardian, and water guns and water cannons should be used for cover when necessary; the sewers and rainwater outlets and all possible escape routes should be closed. If possible, the rainwater outlets or sewers can be blocked and capped, and the leakage of hazardous substances can be confined to a specific area (confinement) through limited measures. These measures are basically defensive (defensive), and generally speaking, most of them are implemented far away from the leakage.

This can be done by the following methods:

Covering and dilutionTo reduce the evaporation rate of volatile liquid chemicals in the atmosphere, foam can be covered on the surface of the leak to form a covering layer, or coolant can be spread on the entire surface of the leak to fix the leak, thereby reducing the evaporation of the leak, reducing its harm to the atmosphere and preventing the combustion of combustible leaks.

Usually, foam covering is only applicable to land leaks, and appropriate foam is selected according to the characteristics of the leak. Generally, foam should be covered every 30-60 minutes to effectively control the volatilization of the leak. In addition, foam covering must be used in conjunction with other containment measures such as dike building and trench digging. Commonly used coolants include carbon dioxide, liquid nitrogen and ice. The coolant should be selected based on the cooling effect of the coolant on the leak. Environmental factors at the accident site and the impact of cooling on other subsequent treatment measures. Usually, a water gun or fire hose is used to spray mist water at the harmful vapor cloud to accelerate the diffusion of the gas to high altitudes so that it can diffuse in a safe area.

When using this technology, a large amount of contaminated water will be generated, so the sewage discharge system must be unblocked (it is best to treat the contaminated water to reduce its toxicity and avoid direct discharge into the sewage system, especially the rainwater system. If the water contains high concentrations of dangerous toxic substances, it will inevitably cause corresponding pollution). For combustible materials, a large amount of water vapor or nitrogen can also be released on site to destroy combustion conditions.