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Six key elements to consider when dealing with chemical disaster incidents: With the rapid development of China’s economic construction and society, especially since the beginning of the 21st century, toxic gas incidents and chemical leakage disasters have been occurring frequently around the world. On December 3, 1984, 45 tons of highly toxic methyl isocyanate were released from a pesticide factory in Bhopal, India; the substance spread over an area of about 49 square kilometers carried by the wind, resulting in the death of more than 3,000 people, blindness in over 50,000 people, treatment for more than 100,000 people, and forced displacement of over 200,000 people from their homes. Within China, the massive explosion at the Qingshuihe chemical warehouse in Shenzhen in 1993 caused direct economic losses of over 200 million yuan. On April 16 of this year, an explosion and leak of chlorine gas occurred at the Tianyuan Chemical Factory in Chongqing, resulting in 9 deaths and the evacuation of 150,000 people. The occurrence of these chemical disaster incidents has not only caused severe losses to people’s lives and property but also posed a severe challenge to frontline fire commanders who are responsible for rescue operations. Here, the author discusses the six key elements that must be taken into account when dealing with chemical disaster incidents, in light of the characteristics of such incidents. Chemical disaster accidents refer to situations in which toxic and hazardous chemical substances leak, explode, or catch fire during their production, use, storage, or transportation, resulting in numerous casualties, significant social impacts, and severe environmental pollution. Such accidents are characterized by sudden onset, rapid spread, wide range of impacts, multiple ways in which harm can occur, difficulty in detection, challenges in rescue efforts, environmental contamination, difficulties in cleanup, broad societal implications, and **significant consequences. I. Rescue personnel must be familiar with chemical disaster response units. The duty squad must be familiar with the properties, characteristics, and handling methods of chemical hazards in its jurisdiction, as well as the strategies for combating such hazards. It should also know the prevailing wind directions in that area throughout the year. In addition, training and practical drills related to protection, detection, leak sealing, demolition, rescue, transfer, and decontamination should be carried out in accordance with the established procedures for dealing with chemical hazards, so that the personnel on duty can have a clear understanding of the situation. Only then can they remain calm in emergency situations and make full use of their skills and tactics. II. The warning zone should be designated reasonably. The time and location of chemical disaster incidents are uncertain and random, with a high degree of suddenness; they can lead to the release of large amounts of toxic and harmful substances in a short period of time. Affected by various factors such as climate, geographical conditions, and the causes of the incident, these disasters result in widespread dispersion and pollution ； Furthermore, after a sudden chemical disaster occurs, the toxic gases spread rapidly in the downwind direction, and most of these harmful substances can severely contaminate the air, soil, water sources, as well as industrial and residential facilities. In a short period of time, the area affected can reach dozens or even hundreds of square kilometers, resulting in pollution over a large scale and **increased** damage effects as well as more pathways through which harm can be inflicted. Toxic gases can cause poisoning of various systems in people without protection, such as the respiratory and digestive systems, through various routes including the respiratory tract, eyes, and skin mucosa ； In addition to contaminating the ground, rivers, and other surfaces, toxic liquids can also cause direct poisoning in people. Moreover, the random movement of poisoned victims and vehicles can expand the scope of damage, leading to indirect poisoning and injury in other people as well. Therefore, the on-site commander must establish reasonable security zones based on the actual conditions at the disaster site, dividing these zones into: high-risk areas, low-risk areas, and safe areas ； Isolation zones may be established outside the safe area as appropriate, and strict control is exercised over the entry and exit of people and vehicles in various areas, with registration required. III. It is necessary to obtain clear information through inquiries of those with knowledge of the situation and instrument detections. After rescue personnel arrive at the disaster site, the on-site commander should ask in detail those with knowledge of the situation, and find out information such as the number of people trapped, the substances that have leaked, the time and location of the incident, nearby facilities, residents, the terrain, power supply, and fire sources. When those with knowledge of the situation have been injured, killed, or fled the scene, rescue personnel should make full use of detection instruments and other effective methods to accurately determine technical parameters such as the type and concentration of chemical hazards as well as temperature. Based on their hazard level and the specific conditions at the scene, they should develop scientific and reasonable fire suppression and emergency response plans, and establish appropriate tactical measures for extinguishing the fire and dealing with the emergency. IV. Action must be taken quickly to close valves and stop leaks. Upon the arrival of the rescue personnel, they should locate a water source nearby, lay out main supply lines, establish positions, and carry out their tasks in an organized manner; they should also set up water screens and hoses to create water barriers that will help dilute and reduce the concentration of the leaked substances ； A water curtain is created using spray nozzles to prevent the spread of leaks toward important targets or hazardous areas. If toxins continue to leak, it is necessary to promptly obtain from the person in charge of the facility and relevant technical personnel information regarding the name of the toxic substance, its physical and chemical properties, the type of toxicity, the production process, and the technical requirements associated with it ； After carefully studying the implementation plans for shutting off valves and sealing leaks, it actively cooperated with the relevant technical personnel from the accident-affected unit as well as skilled workers to carry out these tasks under strict safety measures. V. The fire extinguishing agent must be selected correctly. In many chemical hazard accidents, it isn’t a single substance that is burning, but rather a mixture of various chemicals undergoing combustion; this requires us to use the appropriate fire extinguishing agents correctly. For example: Most flammable and combustible liquids can be extinguished using foam ； For water-soluble organic solvents, resistant foam should be used ； Flames caused by combustible gases can be extinguished using extinguishing agents such as CO2, dry powder, and halons; toxic gases and acids or bases can be diluted using spray or misted water flow ； For fires involving water-reactive materials and metals, water should not be used for extinguishing them, nor should fire extinguishing agents such as CO2 or \"1211\" be used; it is advisable to cover the fire with dry powder or sand ； For light metal fires, 7150 light metal fire extinguishing agent can be used. When the burning material is only partially on fire and can be extinguished using water or foam, water guns or foam nozzles should be immediately deployed to contain the fire, cool the containers exposed to the flames, and prevent the packaging containers from breaking and the fire from spreading. If the burning material is a chemical substance that cannot be extinguished with water, appropriate fire extinguishing agents should be used, or the area should be covered with materials such as sand, soil, or asbestos blankets to put out the fire promptly. VI. Decontamination must be carried out promptly. Following a sudden chemical disaster, toxic and harmful substances can contaminate the air and the surfaces of objects. Toxic gases can be present everywhere or remain trapped in any part of the contaminated area without escaping, while toxic liquids can penetrate the surface of the ground, causing severe damage to the ecological environment and the atmosphere. Once a contaminated area is formed, it becomes difficult to carry out thorough decontamination due to the size of the affected area and its geographical characteristics. Therefore, after dealing with chemical disaster incidents, the site must be decontaminated promptly, and the wastewater generated from this decontamination process must also be tested by environmental protection authorities to prevent further damage and secondary accidents. If you see it, you should support it; one should be honest and upright:victory: