Mobile phone radiation and protective measures
1. The source of electromagnetic radiation Electromagnetic radiation refers to the phenomenon in which energy is emitted from the source into space in the form of electromagnetic waves. The electromagnetic environment is the sum of all electromagnetic phenomena existing in a given place. Due to the development of human society, the advancement of science and technology, and the expansion of the size of cities, the electromagnetic radiation environment in cities is deteriorating.
There are many reasons for electromagnetic pollution: the expansion of the urban area has made the high-power electromagnetic launching stations in the suburbs gradually surrounded by new residential areas; the development of satellite communications has caused many satellite ground stations in the suburbs of the city, and some areas transmit antennas More than 20 mobile communication technologies have developed rapidly. Mobile communication base station antennas are lined up in high-rise buildings in urban areas. Some unreasonable antennas have caused pollution to the electromagnetic environment of high-rise residential buildings. The electromagnetic noise formed by urban transportation systems has increased.
There is also a development trend of electromagnetic pollution in the small family environment. Electronic equipment such as computers, microwave ovens, electromagnetic stoves, mobile phones, electric blankets, refrigerators, etc. are increasingly entering the home. Household electronic equipment greatly facilitates our lives, but if used improperly, it will also cause deterioration of the electromagnetic environment.
Mobile communication is a rapidly developing radio communication method in cities in recent years. Electromagnetic wave signals are transmitted in a straight line, and it is necessary to construct multiple base stations on urban high-rise buildings. According to survey statistics, there are more than 3,000 paging stations, "Big Brother" stations, and dedicated cluster network base transmitting stations in the Beijing area, and there are about 6 base stations per square kilometer in the built-up area (in terms of 488 km2). Most of these base stations are located in densely populated areas.
In fact, the radiation of the base station to the surrounding environment is determined by a variety of conditions such as orientation, direction, and height difference. If the layout is reasonable, there will be no impact on the surrounding environment. If there are buildings with low height around the base station, the radiation has attenuated in the air. If there are high-rise buildings around the base station, but because the building is not in the main radiation direction of the antenna, electromagnetic radiation will basically not affect the environment.
Not long ago, some people in a county in Jiangsu discovered that their lights did not need to be turned on and turned on every day. When the telephone receiver in the house was picked up, there was music. This strange phenomenon terrified people and thought that there was a disaster. After checking by the local environmental monitoring department, it turned out that the radio antenna of the radio station was too close to the resident ’s house, which caused the electric light of the resident ’s house to be electrified. , The phone is also affected by this interference. This is an example of the serious pollution caused by electromagnetic radiation to the surrounding environment.
Second, when it comes to health hazards, people will think of the lethality of atomic bombs. You have been seriously injured before you feel pain. Electromagnetic radiation is certainly not as terrible as nuclear radiation, but it is also very dangerous and everywhere. Household appliances such as microwave ovens, computers and mobile phones all have electromagnetic radiation, which is the electromagnetic waves of various wavelengths and frequencies generated when the household appliances are working. According to observations by medical scientists, headaches, insomnia, forgetfulness and other "sub-health" performances are associated with increased heart rate, respiratory disturbances and electromagnetic radiation. It also "helps" the growth of cancer cells and increases the incidence of cancer.
The bad news from home and abroad is consistent: Although the health standards for short-range radiation in different countries are different, experiments have shown that the electromagnetic radiation of many mobile phones exceeds some health standards, which will cause people to suffer from neurological and mental disorders. Such as nervousness, insomnia, bloating, headache, general weakness, etc. People who use mobile phones for more than one hour a day often experience facial tingling, ear fever, dizziness, and fatigue. A survey of people who use mobile phones and those who do not use mobile phones conducted by China Environmental Health Monitoring found that people who often use mobile phones are more prone to neurasthenia, headaches, insomnia and sleeplessness than those who do not. Some people have proposed "electromagnetic radiation sensitivity syndrome", that is, some people are particularly uncomfortable with electromagnetic radiation like pollen allergy.
When using a mobile phone, the local environment has strong electromagnetic waves that exceed the standard. Although the transmission power of the handheld phone has been reduced, because the phone antenna is too close to the brain (5-10 cm) during the call, long-term calls will be exposed to electromagnetic waves for a long time. However, how long the call is considered to be "excessive use" is currently inconclusive. There is an accumulation process of electromagnetic radiation. It is certain that the use of mobile phones will cause certain functional hazards, but it should be said that the impact on the human body is not too serious.
Normal heart function is inseparable from the potential balance generated by potassium, sodium, calcium, and magnesium ions. External electromagnetic waves can seriously interfere with the physiological process of the myocardium. Tests have shown that electromagnetic waves from cell phones can cause abnormal ECG. Those who are equipped with a heart monitor can affect the monitoring results with their hands, leading to misdiagnosis. There are data to prove that severe electromagnetic radiation has teratogenic effects. Therefore, pregnant women should not use mobile phones. Mobile phones can also cause internal secretion disorders and affect lactation. Breastfeeding women should also avoid using them.
3. Radiation protection Earphones can effectively reduce the influence of mobile phone radiation. The use of mobile phone personal hands-free device can effectively reduce electromagnetic radiation. Compared with directly answering the mobile phone to the ear, the hands-free device has a significant reduction in SAR (Specific Absorption Rate). By using hands-free devices, mobile phone users can reduce the radiation they receive when using mobile phones. The so-called hands-free device refers to a light-weight earphone, which is composed of a small earpiece and a microphone, and is connected to a mobile phone through a wire.
The headphones output audio signals, which are separate from the RF signal. Moreover, the length of the headphone cable is very short compared to the audio length, and there is no possibility of resonance around the headphone cable. Therefore, the headset cannot function as an antenna to concentrate electromagnetic waves.
2. Microwave radiation is strong, and children use cell phones with caution. Researchers observed a strange result from nematodes exposed to microwave radiation: microwave radiation has a similar thermal shock effect on proteins, that is, similar to slight cooking. The long-term release of powerful electromagnetic waves on the side of the brain will affect the brain development of children, and severe cases will induce brain tumors. For safety reasons, it is recommended to limit the time children use mobile phones.
3. The moment when the mobile phone is turned on, the farther from the head, the better. The moment when the mobile phone is turned on is the "most dangerous moment", which is the most harmful to the human body. This is because the microwave radiation energy released when the mobile phone is turned on will be greatly increased, thereby damaging human organs and even causing cancer. The microwave radiation energy emitted by the mobile phone is the largest, and it can be reduced to the normal level after a few seconds of release. This is called "instantaneous phenomenon". The user of the mobile phone has the organs of his body, especially the brain, the farther away from the mobile phone, the better.
4. Precautions for playing mobile phones From the above, the following precautions for using mobile phones can be summarized: Do not use mobile phones for long periods of time; Try to reduce the time of each call; When using mobile phones to talk, one side of the head or face feels hot When the phenomenon occurs, you should stop the call immediately; the electromagnetic wave is strongest when the phone rings, it is best to take the phone away from your body to connect it, and then put it in your ear to talk; it is best to use separate headphones and a separate microphone; the signal is not Pull out the antenna in a good place; avoid using your mobile phone while driving.
The electromagnetic radiation problem of mobile communication is getting more and more attention. The World Health Organization calls on the general public and government authorities to act spontaneously to urge mobile phone manufacturers to reduce the electromagnetic radiation intensity of their products. In order to alleviate some people's nervous attitude about mobile phone radiation, the American Telecommunications Industry Association stipulates that mobile phone manufacturers should explain the radiation information of mobile phones on the packaging.
The number of mobile phone users in China has surpassed Japan, ranking second in the world. While improving the coverage of cellular networks and improving service levels, mobile communication operators are taking measures to solve the electromagnetic radiation problem of mobile communication. For example, the Beijing area has made regulations and relevant standards on the management of electromagnetic radiation: units building wireless paging communication, trunking communication and cellular communication mobile communication stations (stations) in residential buildings. Resident's opinion; within 50m of the main radiation direction of the transmitting antenna and within 30m of the non-primary radiation direction, there should generally be no hospitals, kindergartens, schools, residences and other buildings higher than the antenna; the construction unit should install electromagnetic radiation warning brand.
In response to the current problems of electromagnetic radiation in mobile communications, some local environmental protection departments have also formulated countermeasures. The existing base stations should be re-examined. If they are qualified, a report can be issued and they can continue to be used; if they are not qualified, they must be rebuilt or relocated. The newly built base station shall be approved by the environmental protection department to assist in site selection, and shall not be put into use until it is qualified by the environmental protection department after completion.
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