1, radio and television transmitting equipment, the main sectors of radio and television broadcasting stations and relay stations around the world.
2, communications radar and navigation transmitting equipment communications, including short-wave transmitters, microwave communication stations, terrestrial satellite communication stations, mobile communication stations.
3, industrial, scientific research, medical high-frequency equipment
These types of equipment to convert electrical energy into heat or other energy to be utilized, but accompanied by electromagnetic radiation generated and leaked out, causing environmental pollution in the workplace. Industrial electromagnetic radiation equipment: mainly for the high-frequency furnace, plastic heating machine, high-frequency media heating machine. Medical electromagnetic radiation equipment: mainly for high-frequency physiotherapy machine, ultra-short-wave physiotherapy machine, ultraviolet radiation physiotherapy machine. Scientific research electromagnetic radiation equipment: mainly for the electronic gas pedal and a variety of ultrasonic devices, electromagnetic cooker and so on.
4, electromagnetic radiation interference in the transportation system, including: electrified railroads, light rail and electrified railways, rail trams, trackless trams and so on.
5, electromagnetic radiation in the power system, high-voltage transmission lines, including overhead transmission lines and underground cables, substations, including power plants and transformer power stations.
6, household appliances electromagnetic radiation, including computers, monitors, televisions, microwave ovens, wireless phones. Electromagnetic radiation harms the human body mechanism. Electromagnetic radiation harms the human body mechanism is mainly thermal effect, non-thermal effect and cumulative effect, etc. 1, thermal effect: more than 70% of the human body is water, water molecules are friction with each other by electromagnetic radiation, caused by the body temperature, thus affecting the normal work of the organs in the body. Generate thermal effect on the corresponding electromagnetic wave power density in 10mW/cm2; microscopic thermal effect 1 mW - mW/cm2; shallow thermal effect in 10mW/cm2 below. Thermal effect can cause irreversible damage to human tissues or organs, such as: eye cataracts, male infertility: when the power of 1000W microwave direct irradiation of people, can cause death in a few seconds.
2, non-thermal effects: human organs and tissues are weak electromagnetic fields, they are stable and orderly, once the interference of the external electromagnetic fields, weak electromagnetic fields in equilibrium is about to be reflected in the following aspects of the non-thermal effect on the human body:
Nervous system: the human body is repeatedly subjected to electromagnetic radiation, the central nervous system and other aspects of the function of the changes. Such as conditioned reflex activity is inhibited, bradycardia and so on.
Sensory system: low-intensity electromagnetic radiation, can make people's olfactory function decline, when the human head by low-frequency low-power acoustic pulse irradiation, it will make people hear as if the machine ringing, insects or birds chirping sound.
Immune system: China has a preliminary observation, long-term exposure to low-intensity microwave people and normal people of the same age, compared with its body fluids and cellular immunity indicators in the immunoglobulin 1gG decreased, T-cell wreaths and lymphocyte conversion rate of the product of the decrease, so that the human body's ability to reduce the body fluids and cellular immunity.
Endocrine system: low-intensity microwave radiation can make human thalamus - pituitary - adrenal dysfunction; CRT, ACTH activity increases, endocrine function is significantly affected.
Genetic effects: microwave can damage chromosomes. Animal experiments have been found; with 195MHz, 2.45GHz and 96Hz microwave irradiation of rats, will form chromosome defects in 4-12% of spermatogonial cell bone, rats can inherit such defects, chromosome defects can cause mental retardation, shorten the average life expectancy of the injured.
3, cumulative effect: thermal and non-thermal effects on the human body, the human body has not yet had time to repair itself before the injury, again subjected to electromagnetic radiation, the degree of damage will occur cumulatively, and in the long term, will become permanently sick, life-threatening. For long-term exposure to electromagnetic radiation group, even if the power is very small, low frequency, may also induce unexpected lesions, it causes vigilance. The harm of electromagnetic radiation pollution mainly includes interference with electrical equipment and the negative impact on human health two major aspects.
1, there are three kinds of interference with electrical equipment:
One is the rapid development of wireless communications, but the transmitter, the station's construction lack of reasonable planning and layout, so that aviation communications received interference, such as August 13, 1997, Shenzhen Airport due to the dozens of wireless paging stations on the nearby hills emitting electromagnetic radiation on the airport command tower of the radio communication system caused serious interference, make the ground-to-air command failure, the airport was forced to close for two hours.
The second is that the high-frequency industrial equipment used by some enterprises caused interference with radio and television signals, making it impossible for the surrounding residents to watch television normally and leading to serious mass disputes. For example, the stationery factory in Beijing's Dongcheng district had its factory's high-frequency heat-laminating machine interfered with a television station's broadcast of a sports match, and the factory's glass was smashed by an angry crowd.
Third, some of the original radio stations located in the outskirts of the city, and later with the development of the city is surrounded by urban areas, the surrounding environment has changed from sparsely populated to densely populated, the radio station emits electromagnetic radiation interference with the local hundreds of television viewing.
2, on human health has five major effects:
One, electromagnetic radiation is the main cause of cardiovascular disease, diabetes, cancer mutation. The United States, a cancer treatment foundation for some of the electromagnetic radiation damage to a sample of patients, the results show that people working near high-voltage lines 24 times faster.
Two, electromagnetic radiation on the human reproductive system, the nervous system and the immune system caused direct harm. Damage to the central nervous system, the head of the long-term impact of electromagnetic radiation, light cause insomnia, headache, dizziness, fatigue, memory loss, irritability, depression and other neurasthenia, heavy cerebral cortex cells weakened activity, and cause brain damage.
Three, electromagnetic radiation is caused by pregnant women miscarriage, infertility, teratology and other pathologies predisposing factors.
Electromagnetic radiation is harmful to the human body in many ways, women and the fetus is particularly vulnerable, the survey showed that: 1 to 3 months for the embryonic period, by the strong electromagnetic radiation may cause limb defects or deformities; 4 to 5 months for the fetus to grow up, by the electromagnetic radiation can lead to immunity function is low, the body is weak after birth, poor resistance.
Four, excessive electromagnetic radiation directly affects children's tissue development, bone development, vision loss; liver hematopoietic function decline, serious can lead to retinal detachment.
Injury to the eye power density and the formation of cataracts in the time of the threshold curve is not a straight line, irradiation of the rabbit's eye at each frequency seems to require a microwave power density threshold, below which the curve, even if continuous irradiation does not produce eye damage. Above 500 MHz, the minimum power density for cataract formation is about 150 mW/cm2, and the possibility of eye damage caused by frequencies below 500 MHz cannot be completely excluded.
V. Electromagnetic radiation can make men's sexual function decline, women's internal disorders, menstrual disorders.
In 1998, the World Health Organization (WHO) on the computer screen and workers' health issues in the latest revision of the opinion that: in the computer screen work environment, some factors may affect the outcome of pregnancy. The first affected is the male, long-term exposure to electromagnetic wave irradiation, it is possible to make male sperm reduction, so that sperm genetic deformities and may become sterile or teratogenic; secondly, pregnant women, it has been reported that in front of the computer 1 week of work for more than 20 hours of pregnant women to give birth to deformities of probability than the average pregnant woman 2-3 times higher than the probability of having a large number of girls. Finance: due to the widespread use of computer networks, modern office facilities, operators are directly exposed to electromagnetic radiation.
Broadcasting: radio and television transmission systems, radio transmission systems, editing machine rooms, studios all emit large amounts of electromagnetic waves to the outside.
IT: computer systems and networks emit large amounts of electromagnetic waves at any time.
Electric power: high-voltage transmission, substation, power generation facilities generate high-intensity electromagnetic waves.
Telecommunications: mobile communication base stations and other wireless communication systems electromagnetic wave intensity is very large, especially the harm of cell phones on the human body has aroused widespread concern.
Civil aviation: civil aviation command tower and the aircraft itself are sent out a lot of electromagnetic waves, this industry should pay particular attention to the protection of personnel.
Railway: electrified railroad power lines and variable distribution system emits a large number of electromagnetic waves to the outside.
Medical: high-frequency physiotherapy, ultra-short-wave physiotherapy and various types of spectrum instruments, are emitting a large number of electromagnetic waves.