High temperature defense science knowledge

I. Recognize the hot weather

In China's meteorology, temperatures above 35 °C can be referred to as "high temperature weather." If the maximum temperature exceeds 35 °C for several consecutive days , it can be referred to as "high temperature heat wave," which usually refers to a sustained high temperature process. Due to the high temperature for a long time, people, animals and plants cannot adapt and have adverse effects. A kind of meteorological disaster.

"High-temperature heat wave", also known as high-temperature heat, is a meteorological term that usually refers to high-temperature weather above 35 °C for many days . The criteria for high-temperature heat waves are mainly based on the degree to which high temperatures affect or harm the human body.

High temperature is also a relatively common meteorological disaster. In addition to our country and other parts of the Qinghai-Tibet Plateau, the vast majority of places there have been almost hot weather, including the northernmost Mohe (June 2010 has five hot weather). The hot weather in China is mainly concentrated in May - October . From a geographical point of view: Jiangnan, South China, Southwest China and Xinjiang are all hot spots. According 1951--2009 years of statistics, in the provincial cities of our country (excluding Lhasa no hot weather), the maximum number of Chongqing appears, up to 1853 days; Xining, at least, only three days. China's Xinjiang Basin is also a frequent occurrence of high temperatures, and many times in the entire month ( 6 , 7 , and 8 months) like Turpan are high temperatures.

In the summer season, under the control of the subtropical high in the western Pacific, the Changjiang River in the middle and lower reaches of the Yangtze River has a hot and hot weather, which is the hardest hit by the summer heat waves in China. In July and August after the rainy season , high temperatures occur in general years of 20 to 30 days, and the number of high temperature days in the short years of the Meiyu period may exceed 40 days. Nearly 50 years after presenting the national average daily high temperature first decreased and then increased trend, the early 1950s to the 1980s to reduce the high temperature for several days, in the early 1980s began to show a significant increase in the trend. There is a linear increase in the number of high-temperature days in northwest and north China, with the most obvious increase in South China.

High temperatures have a certain influence on people's daily life and health as well as on various sectors of the national economy. High-temperature heat waves make the human body feel uncomfortable, work efficiency is low, and the incidence of diseases such as heat stroke, intestinal diseases, and cardiovascular and cerebrovascular diseases increases. As the demand for hydropower used for heatstroke cooling increases sharply, the supply of water and electricity is strained and frequent failures occur. The high temperature exacerbates the evaporation of soil moisture and the transpiration of crops. When the high temperature and little rain occur at the same time, it causes serious soil loss, accelerates the development of drought, and has a greater impact on agricultural production. Continuous high temperature and low rainfall can also cause fires, and forest fires can cause damage to the ecological environment. In addition, tourism, transportation, construction and other industries will also be affected to varying degrees.

Second, the danger of high temperature

High temperature is a disastrous weather that will have an adverse effect on people's work, life, and body. People will be prone to fatigue, irritability, and anger. Various kinds of accidents will increase, and even the crime rate will increase. At the same time, the high-temperature period is the period of multiple diseases such as cerebrovascular disease, heart disease and respiratory tract, and the mortality rate is correspondingly higher, especially the mortality rate of the elderly is even more pronounced. Therefore, the health care of the high temperature season, especially the health care of the elderly, is even more important.

As we all know, human body temperature is constant, so why is it comfortable to be comfortable in sunny spring or golden winds, and it is very difficult to be in the summer of summer? This is because different temperatures have different effects on human physiology activities. High temperature is unfavorable to the regulation of human body temperature. Under normal circumstances, the body regulates body temperature through conduction, convection, radiation and evaporation of water, making it suitable for external and internal conditions. In the hot weather, the human body is difficult to dissipate heat, the body temperature regulation function is limited, and it is easy to cause heat to accumulate in the human body and cause heat stroke. Therefore, high temperature is a disastrous weather, especially a persistent high temperature, which is harmful to the human body. Big.

Meteorologists have determined that the difference between the average temperature in the hottest month and the average temperature in the coldest month is generally above 20 degrees Celsius . The difference between the northeast and northwest regions can even reach 40 degrees Celsius or more. The difference in extreme temperatures is even greater, reaching 60 to 70 degrees Celsius in the north and 40 to 50 degrees Celsius in the south .

It is determined that when the temperature is 35 to 39 . At 9 degrees Celsius , people feel strangely hot; when the temperature is higher than 40 degrees Celsius , people feel hot and hard. The normal temperature of the human body is 36 to 37 degrees Celsius. If the hot weather lasts for a long time, it will bring serious harm to the normal activities of the body. Special attention should be paid to the cooling of the heatstroke.

Continuous hot weather can also cause high-temperature heat damage in agricultural production. The early rice in the late grain filling stage will be subjected to “high temperature ripening”, resulting in a lack of grain and a decrease in grain weight. It will also cause the fruit of navel oranges, citrus fruits, etc. to fall off seriously, and agricultural production will be greatly affected.

The main effects of high temperature on human health are the occurrence of heat stroke and the induction of death from heart and cerebrovascular diseases. Under the influence of high ambient temperature, body temperature regulation mechanism is temporarily impeded, and heat accumulation occurs in the body, resulting in heat stroke. According to the onset of symptoms and degree of heat stroke, it can be divided into: heat collapse, is the mildest manifestation of heat stroke, but also the most common; heat radiation, is a long-term work in high temperature environment, resulting in lower extremity vasodilation, blood deposition, and fainting; sunstroke is Due to prolonged exposure, it caused sweating dysfunction. For people suffering from high blood pressure, cardiovascular and cerebrovascular diseases, in the environment of high temperature, humid, windless and low pressure, the perspiration of the human body is suppressed, the accumulated heat in the body is increased, the oxygen consumption of the myocardium is increased, and the cardiovascular state is in a state of tension. Causes the human blood vessels to dilate, blood viscosity increases, prone to cerebral hemorrhage, cerebral infarction, myocardial infarction and other symptoms, which may lead to serious death. According to a survey of cardiovascular and cerebrovascular diseases in Beijing, high-temperature hot weather is a dangerous weather that causes ischemic stroke. In the hot summer months, hot winds (cold summer), diarrhea, and skin allergies are also common. The reason is that due to the high temperature environment, the body is metabolically prosperous, and the energy consumption is large, and the stuffiness often leads to insufficient sleep, loss of appetite, and a decrease in human immunity. At this time, air conditioners or fans are used without restraint to relieve summer heat. Time is too low temperature environment, the body's adaptability decreases, resistance decreases, germs, viruses will take advantage of, easy to cause upper respiratory tract infections (cold); In addition, high temperature and humidity environment, bacteria, viruses and other microorganisms breeding , Food can be easily spoiled and deteriorated. After eating, it can cause indigestion, acute gastroenteritis, dysentery, diarrhea and other diseases; and people return home from the high temperature environment outside, and they are used to immediately turn on the air conditioner or use electric fans to blow and eat. Some cold foods, this cold and hot, immediately effective, immediately began to diarrhea; sultry weather, poor perspiration of the human body, but also easily lead to skin allergies, especially children under the age of 10 , mainly for pimples like urticaria, eczema , contact dermatitis, etc., due to children's poor adaptability to high temperature and humidity, mosquito bites, pollen, and dust And so it caused. In addition, indigestion, food products, parasites can also cause illness.

Third, high temperature precautions

1, during the day to avoid or reduce outdoor activities, especially 10-16 Do not go for sports and labor in the hot sun.

2 , should not sleep on the balcony, under the tree or open air, get up early to get up early, noon should be a nap.

3 , outdoor work should wear a straw hat, wear light-colored clothing, and should be equipped with drinking water and sunstroke drugs, such as feeling dizzy feel uncomfortable should immediately stop working, rest in the shade.

4 , when sweating, should not immediately take a bath with cold water, should first wipe sweat, take a short break and then shower with warm water.

5 , air conditioning temperature should be controlled at 26 ~ 28 °C , indoor and outdoor temperature difference should not exceed 8 °C . When air-conditioning is in operation, try to avoid blowing cold air directly from the air outlet or blowing it to a certain part of the body for a long time. Open doors and windows at regular intervals for ventilation.

6 , to avoid the skin was bitten by mosquitoes, boiling water burns, etc., to prevent the infection caused by high temperatures and bacterial growth.

7 , pay attention to food hygiene. To drink more water, add more than 2000 ml of water daily to warm salt water or tea, eat fresh fruits and vegetables.

8 , to calm down in summer, avoid anger and avoid anger, peace of mind nursed back to health, contented.

9. To increase awareness of stroke prevention. Eat small meals and avoid eating too tired to prevent the gastrointestinal tract from competing with the brain when digesting food to increase the chance of cerebral ischemic stroke. Any person with cardiovascular and cerebrovascular diseases and diabetes should adhere to the medication. Once symptoms such as flustered, shortness of breath, dizziness, confusion, unsteady walking, and listlessness appear, they should seek medical attention promptly.

Fourth, high temperature heatstroke weather forecast

In view of the continuing impact of the warm air mass of the continent, at 17:24 on June 2009, the National Meteorological Center of the Central Meteorological Observatory issued a flood in 2009 the first phase of "heat stroke weather forecast" and drew attention to the relevant departments and the public to take measures to prevent heatstroke.

In 2007 , under the guidance of the China Meteorological Administration, the National Meteorological Center and the Chinese Center for Disease Control and Prevention of the Ministry of Health jointly conducted a research project on the “High-Temperature Heatstroke Meteorological Grade Forecasting Techniques” project. Based on the research results of the project, the National Meteorological Center applied meteorological office. in July 2007, initially established a level of heat stroke weather forecast business processes, and on August 1 that year launched a test run business. At present, the National Meteorological Center's Applied Meteorological Office closely monitors high-temperature weather and promptly releases service products for high-temperature weather conditions in Beijing, Tianjin, Hebei, Henan, and Shandong Provinces.

Fifth, high temperature subsidies

The high-temperature subsidy is to guarantee the normal economic construction and production and business activities under high-temperature conditions during the summer season, and to ensure the safety and health of the employees in the labor production process, and decides to appropriately raise the standard for the payment of summer cool drinks for employees. According to state regulations, employers should arrange laborers to pay high-temperature subsidies to workers in high-temperature weather (days with a maximum temperature of 35 °C or higher), work in the open air, and fail to take effective measures to reduce the temperature of workplaces to below 33 °C .

High-temperature weather may not only damage the body of outdoor workers, but also easily lead to safety accidents. Statistical data show that the safety accidents in the three months of July , August and September accounted for more than 30% of accidents in the whole year. Life poses a serious threat.

When high temperatures have surpassed simple natural phenomena and become more and more complicated social issues, it is not only the public that “bakes” it, but also tests the crisis response capabilities of the government and the public administration. It can be seen that high-temperature labor protection and high-temperature subsidies should receive legal care and institutional guarantees. National and all levels of local legislatures should quickly determine certain conditions of high-temperature weather as a natural disaster, using laws to protect citizens under hot weather. The right to health, to specify the competent department of high-temperature labor protection, and to provide specific regulations on how to perform labor protection for workers under high temperature conditions, and to provide specific regulations for the protection of workers under conditions of field, outdoor, high altitude, high heat, etc. Protection subsidies are also made clear to ensure the health and safety of workers.

In the summer, high temperatures occur in various parts of China. The hardest part is the workers' friends who work under the hot weather. Therefore, it is necessary to give certain care to the operators under high temperature.

Sixth, foreign high temperature standards

The World Meteorological Organization recommends that the standard for high-temperature heat waves be: The daily maximum temperature is higher than 32 °C and it lasts for more than 3 days. According to the Royal Netherlands Meteorological Institute, the daily maximum temperature is above 25 °C and lasts for more than 5 days, of which the maximum temperature is higher than 30 °C for at least 3 days . The meteorological departments of the United States, Canada, Israel, and other countries issued high-temperature warnings on the basis of a comprehensive consideration of the influence of temperature and relative humidity on the heat index ( also known as sensible temperature ) . For example, the United States issued a standard for high-temperature warning: when the daytime heat index exceeds 40.5 °C for three consecutive hours or the predicted thermal index exceeds 46.5 °C at any time , a high-temperature alarm is issued.

German scientists developed a human body temperature index based on the human body heat balance model. For example, when the body's physiological equivalent temperature ( PET ) exceeds 41 °C , the death rate of heat rises significantly. Therefore, the human body physiological equivalent temperature ( PET ) is greater than 41 °C for the high temperature heat wave warning standard.

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