More than 60% of people killed in the fire died of smoke, experts reminded—
Be alert to the "invisible killer" in the fire
Zhou Xuewen, deputy minister of the Emergency Management Department, said at the press conference of the State Council Office on April 9 that, from the perspective of the spring fire occurrence in the past years, the forest fire risk levels in North China, Northwest China, East China, South China, and Southwest China were relatively high from January to April, entering May. The fire prevention situation in the forest areas of Northeast and Inner Mongolia is the most severe, and the pressure on spring prevention will be further increased. The string of safety must be tightened at all times to resolutely curb the fires and deaths and injuries of large forests and grasslands.
The sudden forest fire in Xichang City, Liangshan Prefecture, Sichuan Province at the end of March caused significant loss of life and property, and the health damage caused by the fire caused people's attention. On the afternoon of March 30, accompanied by a forest fire, a large amount of smoke drifted downwind into the Xichang urban area. The whole city was shrouded in a layer of yellow smoke. Some residents said that the smoke was diffuse and affected normal breathing.
According to foreign media reports, there are research reports showing that in the summer of 2019-2020, forest fires raging in eastern Australia caused 417 deaths, 1,124 hospitalizations for cardiovascular diseases and 2,027 respiratory diseases, and 1,305 emergency reports of asthma .
The fire demon is "fierce and evil", and the "smoke demon" harms people even more "recklessly." Why does fire smoke pose a risk of death? What diseases can be caused by inhalation of fire smoke? How to minimize the damage of smoke to the body in case of fire?
Smoke is the number one killer
In many fire cases, blazing fires are often not the direct weapons of "burning" people. The thick smoke from the fires is the first killer to kill people. Li Qizhi, director of the safety and security department of Sichuan Cancer Hospital, said that more than 60% of people killed in the fire were killed by smoke. The harm of smoke mainly comes from its toxicity and the small particles of smoke in it.
"Fire toxic mist contains carbon monoxide, carbon dioxide, hydrogen cyanide, acrolein, smog, and toxic gases such as hydrogen arsenide, benzene, hydrogen bromide, diphosgene, Louis, and mustard gas." Li Qizhi said that carbon monoxide poisoning is The main deadly toxicity of heavy smoke.
Li Qizhi said that when the carbon monoxide content in the air is 1.3%, a person will be comatose after breathing several times, which can cause death within a few minutes, and the carbon monoxide content produced by the burning of common building materials is as high as 2.5%. In addition, there are some materials, such as polyvinyl chloride, nylon, wool, silk and other fibrous items that can produce highly toxic gases when burned, which poses a greater threat to people.
We often say "fire is fierce", but in fact the spread of smoke far exceeds the spread of fire. "Smoke can be said to be permeable, and its spreading speed is more than 5 times that of fire. The first floor caught fire, and in ten seconds, the smoke spread on the tenth floor, which may cause people to suffocate and die." Li Qizhi said, the direction of smoke flow is the spread of fire The way, the extremely high temperature smoke, can form a fire in 2 minutes, and can also pose a life threat to people who are far away.
The respiratory tract may be damaged if not in the center of the fire
After the Xichang Mountain Fire, a lot of yellow smoke shrouded the urban area. Although the fire was at a certain distance from the urban area, the poisonous gases in the fire had already "stripped up" the health of the people in the city.
Zhuang Xiang, director of the Second Ward Department of Thoracic Surgery of Sichuan Cancer Hospital and director of the Cancer Prevention and Treatment Committee of the Sichuan Anticancer Association, said that after the human body inhales the toxic gas produced by the fire, it may cause bronchitis and asthma. In severe cases, chemical pneumonia and lung Interstitial or alveolar pulmonary edema and other diseases, patients may appear tearing, sore throat, chest pain, shortness of breath, cough, palpitations, foamy sputum, bloody sputum, dyspnea, cyanosis and other symptoms, severe cases may progress to acute respiratory distress syndrome (ARDS), even causing death.
"This is the human inhalation injury caused by smoke and gas in the fire." Zhuang Xiang introduced that inhalation injury refers to the inhalation of certain chemical components of hot air, steam, smoke, harmful gases, volatile chemical substances caused by the human body Damage to the respiratory tract and lung parenchyma, and systemic chemical poisoning caused by inhalation of toxic gases and substances.
Zhuang Xiang said that mild inhalation injuries are mostly limited to the oral cavity, nasal cavity and pharynx. Clinically, sputum containing charcoal particles can be seen. The oral cavity is red, swollen, and sometimes has blisters. The throat often has slight pain and dryness. And the pharynx, larynx, and trachea, often accompanied by hoarseness, redness and edema of the upper respiratory tract; severe inhalation injury often damages the bronchi, bronchiole, and alveoli, causing airway mucosa shedding, pulmonary edema, and atelectasis. Severe breathing difficulties.
"In addition, due to the hypoxia and vasoconstriction caused by smoke, patients with chronic diseases such as chronic bronchitis and pulmonary heart disease that have existing respiratory and cardiovascular systems can induce acute attacks of the original disease, resulting in asthma and difficulty breathing. , Heart failure, and even life-threatening. "Zhuang Xiang said.
When a fire broke out and met such a fierce "smoker" opponent narrowly, we "can't beat but can hide". "Keep calm, don't escape blindly, first distinguish the direction of the fire source and the direction of the toxic smoke flow, avoid the area with high smoke concentration, and shift to the upwind direction of the fire source." Li Qizhi said, covering with a certain thickness of wet towel when transferring Snout, keep your body as close to the ground as possible while still or passing through smoke.
Li Qizhi said that indoors must first be isolated from smoke, immediately close the doors and windows connected to the toxic smoke area, fill the gap with a soft cloth, and at the same time open the channel that communicates with the outside non-smoke area to keep the room full of oxygen . Then send a distress signal to the outside of the window to wait for rescue, or fasten it with a rope to the fixed objects such as window frames, heating pipes, iron railings, etc., and protect your palms with towels, cloth strips, etc., slide down or down to the unfired floor Dangerous situation.