Prevention and disposal of hazardous chemical accidents

Release time:2023-03-29

Attention should be paid to the way and method of fire treatment of inflammable and explosive dangerous goods, and the rescue treatment policy of "saving people first, scientific rescue" should be implemented. Correct command decisions should be made according to the characteristics of the fire site, and appropriate fire extinguishing agents should be selected for fighting and rescuing.

Diagram of command and Decision procedure for fire fighting of Inflammable and explosive dangerous Goods

Flammable gas

The fire treatment of flammable gas should first try to close the valve to cut off the air source, and at the same time grab out the dangerous goods without fire and put them in a safe area; If it is not possible to transfer, the gas cylinder threatened by the fire must be sprayed with mist water to cool it down and prevent it from exploding due to rising temperature. At the same time, CO2 or dry powder can be used to extinguish the fire. If toxic flammable gas leakage occurs when the flame is extinguished in the process of disposal, attention should be paid to anti-gas and anti-gas diffusion during disposal. At this time, the gas cylinder can be immersed in cold water to reduce the concentration of toxic gas spilled into the air.

Flammable liquid

On the fire site, the container containing flammable liquid should be cooled and evacuated in time to prevent the container from bursting due to the increase of internal pressure caused by heat. When there is a flowing fire, should first try to stop the flowing liquid to prevent its spread; We should not only take corresponding fire fighting and rescue measures according to the characteristics of liquid, but also do a good job of anti-corrosion and anti-gas work. For flammable liquid fires with a relative density less than water and insoluble in water, water should not be used to put out the fire. Foam, inert gas or dry powder should be used to put out the fire. For alcohols, ketones, ethers dissolved in water flammable liquid fire, disposal can not use water to fight, should use anti-soluble or saponified foam to fight. For flammable liquid fires with a relative density higher than water and insoluble in water, water can be used as fire extinguishing agent during disposal.

Flammable solids, substances prone to spontaneous combustion and flammable gas discharge in contact with water

The fire fighting of flammable solid should be controlled quickly, and the flame in the fire area should be extinguished as soon as possible to prevent the expansion of the fire area due to heat transfer. For the fire of flammable solid in bundle state, the external surface flame should be extinguished with water before disposal. In order to prevent its reignition, the bundle must be disassembled to extinguish and cool the internal heat source. Fire of substances prone to spontaneous combustion, such as phosphorus fire, a small amount can be used to clamp it into the water; When the amount of wet sand, wet soil can be used to bury it, can not use high pressure water impact to prevent the melting state of phosphorus splash and expand the scope of the disaster accident. Substances that give off flammable gas in contact with water, such as flammable metal powder fire, can be covered with dry sand, talc or asbestos, and can not use water, CO2 and dry powder fire extinguishing agents that will react with it.

Oxidizing substances and organic peroxides

According to the physical and chemical properties of oxidizing substances and organic peroxides, dry sand, dry soil and dry powder extinguishing agents can be used to extinguish such dangerous goods in case of fire. Water, foam and CO2 are strictly prohibited to extinguish such dangerous goods.

Precautions for Fire Disposal of Inflammable and Explosive Dangerous Goods

1. Fire fighting and rescue personnel should enter the scene in the windward or lateral windward direction. Rescue vehicles should stop in the windward or lateral windward direction and avoid low-lying areas with the front facing the retreat direction. Do a good job of personnel evacuation, irrelevant personnel and vehicles are strictly prohibited to linger in the inflammable, explosive and dangerous goods fire area.

2. Safety personnel shall be set up to observe the fire scene in the whole process. When there are signs of explosion danger that will threaten the life safety of the on-site disposal personnel, the safety personnel shall immediately inform the disposal personnel to evacuate to a safe area.

3. Front-line disposal personnel should be few but precise. When handling inflammable and explosive dangerous goods fire accidents with technological measures, accident units, professional engineering and technical personnel and fire fighting personnel should cooperate with each other and jointly implement.

4. Take ESD measures such as grounding wires when tipping cans of inflammable and explosive dangerous goods. High heat and high energy facilities at the fire site should stop operation, and fire source, power source, static power source, mechanical spark and other ignition sources should be prohibited. Avoid collision and friction of dangerous goods; Avoid vibration and dust on site.

5. Flammable and explosive dangerous goods should be prevented from entering sewers, flood drains and other narrow Spaces during fire treatment. Waste water should be treated under the guidance of the environmental protection department.

The severity of the consequence of fire accident is determined by the fire risk of combustion medium. Relevant personnel should be fully aware of the fire risk of inflammable and explosive dangerous goods and their universality, which is the premise of fire prevention and treatment. Flammable and explosive dangerous goods due to their different physical and chemical properties, different production technology, use, storage and transportation characteristics, the cause of fire is not the same.

keyword: Prevention and disposal of hazardous chemical accidents