Automobile is an important means of transportation in modern times. Various magnetic materials and devices are used in telephones, radios and televisions in automobiles. In some modern new cars, the application of magnetism is more and more. For example, a new type of modern family car uses 32 small permanent magnet motors, which are respectively applied to clock stepping motors, tape recorders, electronic instrument stepping motors, electronically controlled mirrors and automobiles.
Figure 4 The use of modern new cars
Distribution map of various small permanent magnet motors
High-pitched pump, automatic speed regulating pump, starting motor, telescopic headlight, headlight cleaner, water tank cooling fan, capacitor cooling fan, valve control, neck loss control, headlight wiper, front window cleaner, front wiper, rear wiper, electric window, oil pump, automobile door lock, adjustable shock absorber, air purifier, rear air conditioner, automobile antenna and rear window cleaner. Fig. 4 is a schematic diagram of various small permanent magnet motors used in the automobile.
In addition to the above-mentioned household appliances, many kinds of magnetic materials and devices are needed. Many other household appliances are also applied to magnetism, such as magnetic door seals and motors in refrigerators, motors used in washing machines, air conditioners, vacuum cleaners and record players, magnetrons used in microwave ovens, electromagnetic relays used in electric doorbells, and small micro motors used in electronic clocks. It can be seen that modern life is inseparable from magnetism.
Harmful to human body.
Magnetic field belongs to electromagnetic radiation. Although it has a long wavelength, it also has a certain amount of energy. Nuclear magnetic vibration belongs to an experimental technology that uses electromagnetic radiation in this band to achieve detection purposes. What it can cause is the spin motion of the nucleus. So I always think it should be harmful.
I have consulted several nuclear magnetic experts at home and abroad, especially the foreign professionals in Varian, who always ask questions when they visit each year. The answer they have got for so many years is "no impact".
I care so much because I think it doesn't work, but my family has always been wary of fear, especially when my wife was pregnant a few years ago.
People who do MRI say it's nothing, but it's better for pregnant women to be less exposed to electromagnetic fields. Because the so-called no effect is because the shielding effect of the machine is better, it does not mean that the magnetic field is harmless to the human body. For 300MHz instruments, you can do super shielding inside the magnet; But for high-field instruments, the 5 gauss line is still outside the magnet. Moreover, the super shield is horizontal, so it is inevitable to remove the magnet when changing the probe for tuning.
Changes of blood properties under (1) strong magnetic field and its influence on the body. The orientation behavior of human and animal whole blood under strong magnetic field and the action mechanism of main red blood cells have been studied internationally. Changes of blood rheological characteristics under strong magnetic field: changes of blood fibrin activity under strong magnetic field and its influence on biological metabolism: magnetic force, magnetic levitation and light absorption characteristics of human blood under strong magnetic field.
(2) The characteristics and application of protein polymer under strong magnetic field. The orientation of peptides in phospholipids under strong magnetic field has been studied internationally. Phosphorus metabolism of muscle cell protein in magnetic field: structural changes of neuropeptide amino acids and exchange of protein amide and hydrogen under strong magnetic field.
(3) Medical application. In addition to the development of human imaging system, in recent years, the activity of blood fibrin under 4-8 Tesla strong magnetic field and its influence on intravascular thrombolysis have been studied internationally. The influence of strong magnetic field and magnetic field gradient on cellulose dissolution process: the activity of strong magnetic field on animal blood cells and its influence on myocardial protection characteristics; the influence of external magnetic field on platelet fluidity and its application in medical treatment.
Influence of electromagnetic wave on human body
When the human body is in an electric field, the conductivity of the human body makes the current flow into the earth through the skin, and the magnetic field may affect the iron molecules in the blood when passing through the human body. The electric field passing through the skin may cause skin diseases such as eczema. Some people say that women who often use computers are prone to skin aging. Similarly, people realize that electromagnetic waves are more harmful to tissues with rapid cell proliferation, such as blood cells, genitals and lymph, and to children. Let's take the influence of magnetic field on human body as an example to see the harm of electromagnetic wave. When the human body is in a strong magnetic field, various magnetic substances in the body will be attracted by magnetic force. At the same time, due to magnetic induction (the object forming a magnetic field magnetizes other objects), magnetization occurs, that is, magnetic objects such as iron (Fe) in red blood cells in the body are attracted or magnetized, thus affecting other magnetic substances. Obviously, this will be harmful to health. If there are magnetic substances in blood or cells, magnetic induction will hinder the normal activities of blood and cells. The accumulation of heavy metals in the body and the susceptibility to magnetic induction give a fatal blow to the body. However, it is difficult to find out the influence of electromagnetic waves on human body scientifically and carefully. Because various environmental factors act on people comprehensively, it is difficult to do long-term follow-up investigation. The influence of electromagnetic waves on human body has been confirmed by epidemiological investigation and animal experiments.
University of Colorado 1979 N? Professor wertheimer and E? Professor Ripper made an epidemiological investigation between high-voltage power lines and childhood cancer. The results show that the incidence of leukemia in children under strong electromagnetic field is more than three times higher than that in other children. The so-called epidemiological investigation is a research method to compare the factors that cause cancer with the increase rate of cancer patients. A famous epidemiological study is "smoking and lung cancer", that is, comparing the number of lung cancer patients among a large number of smokers and non-smokers. What is studied here is the relationship between smoking and lung cancer. This method is used to study the relationship between electromagnetic waves and childhood cancer. The report has had a great influence not only on the United States, but also on European countries, making people actively study the influence of extremely low frequency electromagnetic waves on the human body. At present, experts and scholars in the United States, Europe, Japan and other countries believe that strong electromagnetic waves are harmful to human body through various animal experiments. 1995110 In October, research institutions in Sweden and Denmark published the research results in the European Journal of Cancer. According to the research report, the incidence of leukemia in children with magnetic fields above 5 mg is five times higher than that in normal children.
Various animal experiments show that electromagnetic waves (1) change nerve conduction substances (2) change the calcium content in cells and cell surfaces of chickens, pigs and mice, leading to fetal malformation and malignant lymphoma (3) reduce the reaction ability of mice, reduce the weight of testicles, change the chemical composition of the brain and slow down the growth rate of the body. The third point will especially affect the delivery of pregnant women and the growth of children. The influence of electromagnetic wave on human body can be roughly divided into thermal effect, stimulating effect and non-thermal effect.
Whether long-term low-frequency electromagnetic waves affect health has become the focus of debate on the harmful theory of electromagnetic waves. The harm of strong electromagnetic waves to human body has been scientifically verified, so all countries in the world have stipulated the maximum time limit of exposure to electromagnetic fields to protect human health.
1. Thermal action
The thermal effect of electromagnetic waves will cause the temperature of tissues and cells to rise. The research shows that the microwave with the wavelength below 3Cm can penetrate the skin 1Cm, while the microwave with the wavelength of 0.25- 1m can penetrate the skin and reach various organs of the human body. Microwave absorbed by the skin is converted into heat, which raises the temperature of body tissues. The results of animal experiments show that the increase of biological body temperature causes behavioral changes and abnormal behaviors. Moreover, the uterine temperature above 39℃ affects the immune function of the body. According to analysis, the most vulnerable places of life are eyes, lenses and testicles, and there are almost no blood vessels. The most serious harm of electromagnetic wave to eyes is lens cataract. At this time, due to the temperature rise, the endoscope produces opaque parts, which makes people unable to see the object clearly. 1- 10GHZ microwave is easy to cause this cataract. Someone has done this animal experiment and irradiated rabbit eyes with 2450MHZ electromagnetic wave (which belongs to the frequency range of microwave oven) for 10 minute. As a result, cataracts began to appear. The testicular temperature of male germ cell aggregate is relatively low (about 36℃) relative to body temperature, and it is very sensitive to heat. The increase of temperature has a decisive influence on the germ cells undergoing meiosis.
Step 2 stimulate
Induction effect in electromagnetic wave stimulation. Electrical signals regulate all functions of the human body. The observation of nerve cells, muscle cells and other cells with the least function that can be excited in human body shows that when the potential difference between the two ends of such cells reaches a certain level, it sends an exciting signal to the nervous system or contracts muscles. However, the external current flowing to human body makes the excitation conduction system of nerve and the biological circuit system of muscle movement system abnormal, which makes human body change. This external current stimulates nerve cells to feel electric shock, and at the same time stimulates muscles to produce muscle contraction or voluntary movement. Stimulate the myocardium to soften the ventricle, the heart stops beating, and stimulate the respiratory muscles to stop breathing.
3. Non-thermal action
Most epidemiological findings such as childhood leukemia caused by electromagnetic fields of high-voltage transmission lines mentioned above belong to this category. At present, it is difficult to confirm the effect of non-thermal action, so it cannot be explained clearly. The cerebral cortex of chickens and cats was placed in UHF and VHF with low frequency modulation, and calcium ions were found to flow out. Information transmission, immune system function and cell proliferation are inseparable from calcium ions. The experimental results show that the low frequency of 50-60HZ also leads to the outflow of calcium ions. It can be seen that general household appliances (60HZ) are also harmful to human body.
Another study reports that the secretion of animal pineal gland (melatonin) inhibits tumor cells, while low frequency changes the secretion of pineal gland.
Extremely low frequency and extremely low frequency electromagnetic waves not only affect the distribution of calcium in human cell membrane, but also affect the distribution of potassium, sodium and chlorine plasma, thus affecting the secretion of human hormones.
As mentioned above, human cells use weak electrical signals to transmit heat, pain, vision and other senses through nerves, but when this communication between cells is hindered, foreign cells will proliferate and form cancer. The external energy that can cause communication barriers is much weaker than expected. In fact, when electromagnetic waves act on the cells cultured in the experiment, it is found that the movement of chemical substances between cells has changed, the production of genetic factors has been hindered, the production of hormones and chemical substances has changed, and the activity of cancer cells has increased. Experiments on mice show that electromagnetic waves will hinder their appetite, breathing, sleep and so on. And human experiments show that electromagnetic waves will weaken the pulse and make brain waves abnormal.
Third, strengthen protection.
The theory that electromagnetic waves are harmful has been questioned, because at present, human beings cannot explain the causes of leukemia and other diseases. Even though modern medicine and science are quite developed, the research on human body is still far from enough. At the beginning of the 20th century, when some scholars suggested that smoking caused lung cancer, they also met with doubts from many scholars, including doctors. It was not until 30 years later that the medical community admitted that smoking caused lung cancer.
The research on electromagnetic waves is only over 20 years. At the same time, unlike smoking, electromagnetic waves are very complicated in intensity, frequency, contact time and waveform, and it is difficult to prove their relationship with cancer. Like smoking, people should raise their awareness of the harm of electromagnetic waves. Based on the current epidemiological investigation, people can't deny that electromagnetic waves have an impact on the human body. Therefore, it is necessary to avoid independent contact with strong electromagnetic fields; When contact is needed, appropriate measures should be taken.
Harm of electromagnetic radiation and its prevention
Electromagnetic radiation and health
The 20th century is called the electrical age. More and more power stations and transmission lines were built, and various electrical appliances went deep into factories, laboratories, offices and ordinary families. However, whether the electromagnetic field, especially the electromagnetic field with power frequency (50-60 Hz) has an impact on human health has always been a concern.
In the early 1960s, relevant experts began to discuss this issue. At first, experts only paid attention to the role of electric field, but ignored the role of magnetic field. Because at that time, people mistakenly thought that the magnetic field component in this electromagnetic field was very small and could not have a perceptible impact on human health. The health care standards in many countries only stipulate the allowable electric field components in the power frequency electromagnetic field; When manufacturing all kinds of electrical equipment and appliances and erecting transmission lines, only the standards specified by electric field components are considered, but the maximum allowable limit of magnetic field components is not considered. However, a large number of investigations and statistical analysis later showed that magnetic fields can also affect human health. For example, the probability of various tumor lesions in human body is closely related to the received low-frequency electromagnetic radiation. Experts in many countries in Europe and America and some government agencies are convinced that low-frequency magnetic fields will significantly increase the incidence of the following diseases: leukocytosis and leukemia (especially more harmful to children), cancer, physical defects of newborns, breast cancer, brain tumors, malignant lymphoma, nervous system tumors, astrocyte development, chronic myeloid leukemia, chromosome aberration and so on. It has also been reported that the decrease in the secretion of some hormones under the action of electromagnetic fields may also be the cause of breast tumors.
So far, there is no direct evidence of the harm of mobile phones to health, but in general, it is better to make a long story short by using mobile phones.
What do you know about electromagnetic radiation?
A survey report pointed out that people who are often exposed to electromagnetic radiation are at greater risk of breast cancer if they are exposed to high temperature again; People who have been electrical engineers for a long time will increase the risk of acute leukemia if they are exposed to gasoline, pesticides or pesticides again.
Many investigation reports also pointed out that people who are engaged in "electrical appliances", children and people who use household appliances improperly (children who often play video games, women and children who often use electric blankets and other heaters, etc.). ) the risk of being damaged by low-frequency magnetic fields is greater. Some countries also have such regulations for pregnant women: the baby can't go to the computer for 3-6 months before birth.
The intensity and accumulation of low-frequency magnetic field radiation will affect the probability of illness. And some people have an incubation period as long as 10- 15 years. According to international health standards, the upper limit of allowable magnetic induction intensity is 100 microtesla. Electromagnetic radiation is just like the relationship between the sun and ultraviolet rays. If you want to enjoy the sunshine, you will inevitably be exposed to ultraviolet radiation. Electromagnetic radiation is invisible, intangible and difficult to perceive, so its harm is particularly hidden. From electronic alarm clocks, hair dryers, microwave ovens and electric irons to computers, fax machines and telephones, we are constantly exposed to electromagnetic "comfort". Out of the house, power lines and all kinds of motor equipment make us very easy to be in the electromagnetic field. The deterioration of electromagnetic environment in 2 1 century is a foregone conclusion.
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Preventive measures of electromagnetic radiation
As we all know, where there is electricity, there is electromagnetic radiation, which is invisible, intangible and impossible to prevent. Then what kind of preventive measures people take is very important.
First of all, we should widely publicize the basic knowledge of electromagnetic radiation, so that people can know how electromagnetic radiation is produced, what harm it will cause to human body, what kind of places to use and what kind of equipment to use will produce electromagnetic radiation. This is a long-term patient and meticulous work.
Secondly, take some necessary preventive measures to avoid or reduce electromagnetic radiation. For example, there is a kind of radiation-proof clothing, which is woven from a variety of electromagnetic radiation-proof raw materials, and its electromagnetic shielding effect is very obvious. If our merchants produce more such clothes, the harm of electromagnetic radiation to human body will be greatly weakened.
How to prevent the harm caused by electromagnetic radiation
1. Prevent the influence of electromagnetic radiation on human body;
(1) Shielding room: made of metal (sheet, net), which is mostly used to shield the activity field of large machinery groups or control rooms;
(2) Protective clothing, protective helmet and protective glasses: These are personal protective articles, which can effectively reduce the intensity of magnetic radiation to protect the health of workers exposed to electromagnetic radiation;
(3) Shielding cover: This is the main method to shield the activity field of small instruments. The materials used for shielding are usually conductive materials with low resistivity, such as copper and aluminum.
(4) For the electromagnetic radiation generated by mobile phones, you can wear headphones to reduce the electromagnetic radiation. According to the experiment of Thiel Laboratory of Institute of Telecommunication Transmission of Ministry of Information Industry, the radiation received by the head when talking with headphones is between1100 and 1/200.
2. The main methods to prevent electromagnetic radiation from leaking computer secrets are:
(1) Passive mode: electromagnetic shielding to prevent electromagnetic waves from leaking out. The disadvantage of using this mode alone is that if the shielding is not complete, the high-sensitivity electromagnetic receiving equipment can still obtain information;
(2) Active mode: emitting electromagnetic waves, and the electromagnetic receiving equipment used for stealing secrets receives the interfered signals. The disadvantage of using this mode alone is that it is still possible to recover useful information if well-designed software is used to analyze the received interference signal.
Therefore, the best way is to mix the two modes at the same time.
Therefore, passive methods are needed to prevent electromagnetic waves from leaking out from these aspects. Just shielding the display is not enough. When using the computer secretly, all unnecessary cables and peripherals should be removed.
A battery-powered laptop can dispense with this connection. However, if public power supply must be used, passive mode filtering equipment or active mode interference signal injection into the power line is a measure that can be considered.
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The harm of electromagnetic radiation to the quality of living environment can not be ignored.
At present, with people paying more and more attention to health, buyers have begun to pay attention to environmental quality in addition to location, price, apartment type, garden and property when choosing housing. It is understood that in order to let people enjoy a safe and healthy living environment, the Law of the People's Republic of China on Environmental Impact Assessment will come into effect on September 1, which means that mandatory environmental impact assessment must be carried out before the establishment of residential projects in the future.
Electromagnetic radiation surfaced.
For outdoor environmental quality, noise, air index and electromagnetic radiation are the three issues that people are most concerned about, especially electromagnetic radiation. Because electromagnetic radiation is invisible, people don't know much about it, and many residents living around high-voltage lines, substations, radio stations, TV stations and radar stations have an inexplicable fear. However, experts from the State Environmental Protection Administration pointed out that although electromagnetic radiation is harmful to some extent, on the one hand, electromagnetic radiation is not harmful at any time and any place; On the one hand, electromagnetic radiation can be shielded, and residents don't have to be nervous about electromagnetic radiation.
Correct understanding of electromagnetic radiation
With the development and progress of society, a large number of equipment and activities with electromagnetic radiation, such as TV towers, radio stations, radars, satellite communications and microwaves, are also increasing. These devices have played an important role in the improvement of human living standards and the progress of social development, and the electromagnetic waves generated at the same time are also an environmental pollution factor. The more social progress, the more serious electromagnetic pollution. Therefore, electromagnetic wave is not only an information carrier and energy flow carrier beneficial to social development, but also a pollution factor harmful to human life, and its harm has been highly valued by the international environmental protection field. Therefore, we should take electromagnetic energy as a resource and make full use of it. It is also necessary to strengthen management and control the negative effects of electromagnetic radiation to a minimum.
According to experts from the State Environmental Protection Administration, from a professional point of view, electromagnetic radiation generally refers to electromagnetic waves with frequencies above 100KHZ. The sources of electromagnetic field are natural and artificial. First of all, the earth itself is a big magnetic field. Sunlight itself is also a frequency band of electromagnetic waves, as well as lightning and electromagnetic waves generated by other planets, which are naturally generated. Human beings have evolved in this environment and formed a harmonious relationship with nature. Therefore, natural electromagnetic radiation does no harm to human body. But since the19th century, with the development of science, people have invented many facilities that use electromagnetic energy to work. These facilities emit a large number of electromagnetic radiation or generate electromagnetic fields to the environment, which makes the electromagnetic radiation problem in the environment more and more serious, thus creating the problem of electromagnetic environmental protection. Facilities that generate electromagnetic radiation can be roughly divided into five categories:
1, radio and television transmission systems, such as TV transmission towers and radio relay stations;
2. Wireless communication transmission systems, such as mobile phone base stations;
3. High-voltage power transmission and transformation systems, such as high-voltage lines and substations;
4. Electrified railways, such as maglev trains;
5, industrial, scientific and medical electromagnetic energy facilities, such as high frequency melting furnace;
Harm of electromagnetic radiation
Humans themselves live in a huge electromagnetic field, and electromagnetic radiation is everywhere, so electromagnetic radiation is not as terrible as imagined. Only when the electromagnetic radiation exceeds a certain value will it have a negative impact on people's health. According to the electromagnetic radiation protection regulations issued by the State Environmental Protection Bureau, the electric field intensity is lower than 40 volts per meter, which should be safe. Even if it exceeds this value, it will not necessarily cause injury, which depends on the individual's resistance and the time and distance of contact. In addition, experts also pointed out that electromagnetic waves are everywhere, bringing infinite convenience to our lives. We should treat them correctly and make rational use of them. There is absolutely no need to worry too much. As long as proper shielding and protection are carried out, the radiation impact can be greatly reduced.
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How terrible is electromagnetic radiation?
In recent years, domestic and foreign media have reported that electromagnetic radiation is harmful: more than 400 children in Italy suffer from leukemia every year, and experts believe that the cause is serious electromagnetic pollution; A cancer medical foundation in the United States sampled some patients injured by electromagnetic radiation. The results show that the growth rate of cancer cells in people working near high-voltage lines is 24 times faster than that of ordinary people. Of the 20 million children born every year in China, 350,000 are disabled children, of whom 250,000 are mentally retarded. Some experts believe that electromagnetic radiation is one of the influencing factors.
Is the harm of electromagnetic radiation really so sensational?
In fact, human beings have been living in an electromagnetic environment. The earth itself is a large magnetic field, and both thermal radiation and lightning on its surface can produce electromagnetic radiation. In addition, the sun and other planets constantly produce electromagnetic radiation from outer space. However, naturally generated electromagnetic radiation is harmless to human body, while artificially generated electromagnetic radiation poses a threat to human body and pollutes the environment.
As early as 168 years ago, Faraday, an Englishman, discovered a wonderful phenomenon: electric field and magnetic field can be generated when current passes through a medium, which is later called electromagnetic induction. In 1980s, people built the first power station in the world by using the principle of electromagnetic induction. Since then, mankind has entered the application era of electromagnetic radiation.
From the first global communication of 190 1 to the large-scale use of mobile communication, as well as the necessary color TV sets and refrigerators, the application of electromagnetic radiation has penetrated into all aspects of human life. While people fully enjoy the convenience and comfort brought by electromagnetic radiation, they also feel its negative effects more and more. For example, electromagnetic radiation in electromagnetic compatibility has caused the navigation system, medical information system, industrial process control and information transmission system to be out of control, which has interfered with people's listening to radio and television. ...
It is said that as long as household appliances, electronic equipment, mobile communication equipment and other electrical equipment are in operation and use, there will be electromagnetic radiation around them. It is also heard that electromagnetic radiation can penetrate many substances, including the human body. So some people compare the pollution caused by electromagnetic radiation of products to "invisible killer", so how much harm will electromagnetic radiation do to human health?
The reporter interviewed Zhao Yufeng, a professor at Beijing Institute of Labor Protection Science.
Professor Zhao said: "Electromagnetic radiation and electromagnetic pollution are two concepts. Although electromagnetic radiation is everywhere, electromagnetic pollution will have a negative impact on the human body only after the electromagnetic radiation exceeds a certain intensity (that is, the limit of safety and health standards), leading to headache, insomnia, memory loss, blood pressure rising or falling, and critical abnormalities in the heart. If you work in an environment with excessive electromagnetic radiation for a long time, it may seriously lead to abortion, cataracts and even cancer in some people ... "
Zhao Yufeng said frankly that the influence of electromagnetic radiation on people is universal, but not terrible. Different people or the same person have different abilities to withstand electromagnetic radiation at different ages. Even in an environment that exceeds the standard, it does not mean that everyone will get sick, so there is no need to be "scared" about electromagnetic radiation. Of course, preventive measures should also be taken for the elderly, children, pregnant women or patients with pacemakers, people who are sensitive to electromagnetic radiation, and people who work in an environment where electromagnetic radiation exceeds the standard for a long time.
In view of the fact that the electromagnetic radiation generated by contact with electrical products in daily life may be harmful to health, the China Consumers Association issued a warning on August 6 that electromagnetic radiation must be prevented in life.
"In fact, whether electromagnetic radiation has an impact on human health is not a new problem." Li Tianlin, a researcher at the Chinese Academy of Preventive Medicine, told the reporter, "For half a century, experts and scholars at home and abroad have been studying and commenting on electromagnetic radiation. However, due to the inconsistency of research objectives, methods and conditions (the distance, time and biological model of exposure to electromagnetic radiation sources are different), the research results and opinions of relevant experts and scholars around the world on the biological effects of electromagnetic radiation are not consistent at present. Therefore, what impact and harm electromagnetic radiation has on the human body needs further discussion. "
However, Li Tianlin believes that China, as a big country, the relevant authorities should formulate a unified national mandatory national standard for electromagnetic radiation safety and health as soon as possible. So that manufacturers can follow this standard to develop ultra-low electromagnetic radiation electrical equipment and ensure the safety of consumers. At the same time, the management of electromagnetic radiation will be included in the normal social environmental protection scope, and the legitimate rights and interests of consumers and workers will be effectively protected.
The reporter interviewed a number of relevant departments on the formulation of electromagnetic radiation standards, and learned that in the past, the Ministry of Health, the Ministry of Electronics Industry (now merged into the Ministry of Information Industry), the State Environmental Protection Administration, the military and other departments all formulated their own electromagnetic radiation safety standards, but there was no unified compulsory national standard for electromagnetic radiation safety. It is reported that at present, China is working on the formulation of mandatory national standards for electromagnetic radiation, which is expected to be introduced before the end of this year.
According to experts from the State Environmental Protection Administration, the electromagnetic radiation environment in China is relatively good at present, which is equivalent to the water pollution and air pollution faced by China in the 1950s and 1960s. There are signs of emergence, far from serious. But from now on, we must strictly manage and plan ahead. Because social and economic development is inseparable from the application of electromagnetic radiation. If the environment cannot withstand electromagnetic pollution, it will be difficult for the economy to develop further.