Possible effects of irradiation doses to the whole body
No significant damage at 0-0.25 sieverts
Changes in the blood can be caused at 0.25-0.50 sieverts, but there is no serious damage
Changes in the blood cells at 0.50-1.0 sieverts, with some damage, but no fatigue
Fatigue at 1.0-2.0 sieverts, with damage and possible weakness of the whole body
At 1.0-2.0 sieverts, there is no fatigue. damage and may feel general weakness
2.0-4.0 sieverts with damage and general weakness, and the frail may die
4.0 sieverts 50% fatal injuries
6.0 sieverts or more may die as a result
Radiation around us
When it comes to radiation, people are a little afraid because it cannot be seen or touched, but can cause harm to the human body. but it can cause harm to the human body. In fact, radiation is not a rare thing, there is radiation everywhere around us. In our daily life, we sunbathe, watch TV, wear a luminous watch, airplanes, X-rays, etc., will be subject to a certain amount of irradiation. It's just that the irradiation in our life is in trace amounts and does not cause harm to the human body, so people don't feel its presence. But a large amount of radiation is very harmful to the human body, so we should prevent and reduce the damage of radiation on our body by taking some corresponding protective measures.
Natural background irradiation
Radiation exists everywhere in nature, and we have been receiving natural background irradiation. There are two sources of natural radiation "background": radiation in the form of energetic particles, which come from outer space and are collectively known as cosmic rays; and natural radioactivity, which occurs naturally in ordinary materials (such as air, water, dirt and rocks, and even food). In addition, people in modern society are also exposed to a variety of man-made radiation, such as X-rays, watching television, using microwave ovens, and so on. The following table lists the various types of background radiation according to their magnitude. From this, we can see that human beings eat, use, live and travel will receive trace amounts of radioactive irradiation.
Source exposure
Living around a nuclear power plant is about 0.0002 mSv per year
Flying in an airplane is about 0.005 mSv per hour
Watching TV for one hour a day is about 0.001 mSv per year
Eating food is about 0.02 mSv per year
Cosmic rays are about 0.03 mSv per year
Earth and housing about 0.05 mSv per year
Smoking 20 cigarettes a day about 0.038-0.075 mSv per year
One X-ray about 0.50-2.0 mSv
Natural irradiation of our high background areas 3.70 mSv per year
Occupational dose limits for radiation workers 50 mSv per year
The world's highest background area of natural irradiation 120 mSv per year
Radiation in the living environment
Chinese Interior Decorators Association Indoor Environment Monitoring Center not long ago issued a warning of the environment: the purchase of housing must pay attention to the community's electromagnetic radiation contamination exceeds the standard. At present, many people have reflected their own new neighborhood electromagnetic radiation pollution is very serious, not only the home of electrical appliances by too much interference can not be used normally, and many people have different degrees of discomfort. With large-scale urban renewal and real estate development, some of the original built in the city around the transmission center and high-voltage lines and other facilities around the development and construction also began, the community environment and the indoor environment in the electromagnetic radiation pollution problems also came. These electromagnetic radiation on the human body harm mainly has 6 aspects. 1, it is very likely to be caused by children suffering from leukemia is one of the reasons. Medical research has proved that prolonged exposure to high electromagnetic radiation can cause changes in blood, lymph fluid and cellular protoplasm. Italian experts believe that more than 400 children in the country suffer from leukemia every year, the main reason is that the distance from the high-voltage power lines is too close, and thus subjected to serious electromagnetic pollution. 2, can induce cancer and accelerate the proliferation of cancer cells in the human body. Electromagnetic radiation pollution will affect the human body's circulatory system, immunity, reproduction and metabolic functions, and seriously induce cancer and accelerate the proliferation of cancer cells in the human body. Swiss research data pointed out that there are high-voltage lines around the household residents, the probability of suffering from breast cancer is 7.4 times higher than ordinary people. Cancer Medical Foundation of Texas, the United States, for some patients who suffered electromagnetic radiation damage to do the sampling laboratory results show that in the high-voltage lines near the work of the workers, the growth rate of cancer cells than the general population to be 24 times faster. 3, affecting the reproductive system, mainly manifested in the reduction of the quality of men's sperm, pregnant women spontaneous abortions and fetal malformations, etc. 4, can lead to children's intellectual disability. According to the latest survey, China's annual birth of 20 million children, 350,000 for defective children, of which 250,000 for intellectual disability, some experts believe that electromagnetic radiation is also one of the factors affecting. The World Health Organization believes that computers, televisions, cell phones electromagnetic radiation on the fetus has an adverse effect. 5, affecting people's cardiovascular system, manifested as palpitations, insomnia, some women's menstrual disorders, bradycardia, decreased blood flow, sinus irregularities, leukocyte reduction, decreased immune function, etc.. If patients with pacemakers are in the environment of high electromagnetic radiation, it will affect the normal use of pacemakers.6. Adverse effects on people's visual system. As the eyes belong to the human body to electromagnetic radiation sensitive organs, too high electromagnetic radiation pollution will cause vision loss, cataracts and so on. High doses of electromagnetic radiation will also affect and destroy the body's original bioelectricity and bio-magnetic field, so that the original electromagnetic field in the body abnormal. It is worth noting that different people or the same person at different ages on the ability to withstand electromagnetic radiation is not the same, the elderly, children, pregnant women belong to the sensitive population of electromagnetic radiation.
Radiation knowledge and radiation around us
Radiation is a kind of energy that spreads in the form of energy beams of waves, particles or photons. Nuclear radiation is the radiation that comes from the nucleus of an atom. There are three main types of nuclear radiation that affect humans, namely alpha, beta and gamma rays. alpha rays are a stream of particles made up of the nucleus of a helium atom. It has a large mass and carries a lot of charge, but its ability to penetrate matter is weak and its range is short, so it can be blocked simply by using an ordinary piece of paper. However, if it enters the human body, it can cause very harmful internal irradiation, so it is important to protect against alpha emitters in particular.Beta rays are composed of high-speed electrons. Compared with α-rays it has greater penetrating power and can penetrate the cuticle of the skin and cause damage to living tissue, but it is easily shielded by materials such as plexiglass, plastic or aluminum plates. The harm of its internal irradiation is also smaller than that of α-rays. γ-rays are similar to X-rays and are also composed of invisible photons. Its penetrating power is the strongest, can penetrate more than one meter thick cement wall, a 1MeV energy of γ-ray is enough to penetrate the human body. Therefore, the protection of γ-rays is the most important in the protection of external irradiation. But because γ rays are not charged photons, it can not be directly caused by ionization, so it is irradiated in the human body harm than α, β rays are small.
Radioactivity is the inherent property of atomic energy to spontaneously emit particles or electromagnetic waves. Nuclides with the ability to spontaneously emit particles or electromagnetic waves are called radionuclides. So far, mankind has discovered 109 elements and about 1,800 kinds of nuclides. 92 of the 109 elements exist in nature, and 17 are artificially created. 270 of the 1,800 kinds of nuclides are stable, and the remaining 1,500 are unstable and are radionuclides. It is easy to understand why our environment is filled with a wide variety of radiation.
Radiation prevention
There are five kinds of people who should pay special attention to electromagnetic radiation pollution: people living and working near high-voltage lines, substations, radio stations, television stations, radar stations, electromagnetic wave transmission towers; people who often use computers, television electronic instruments, medical equipment, office automation equipment; staff living in the environment of modern electrical automation; wearing pacemakers patients; pregnant women, children, the elderly and sick people living in the above environment. If there is a high level of electromagnetic radiation pollution in the living environment, the public must take appropriate protective measures. Do not place household appliances too centrally so as not to expose yourself to the danger of overdose radiation. In particular, some household appliances that are prone to electromagnetic waves, such as radios, televisions, computers, refrigerators, etc. should not be centrally placed in the bedroom. All kinds of household appliances, office equipment, cell phones should try to avoid long hours of operation, while trying to avoid a variety of office and household appliances at the same time. Cell phone connected to the moment of the release of electromagnetic radiation is the largest, in the use of the head and cell phone antenna should try to make the distance a little farther, it is best to use the separation of the headset and microphone to answer the phone. Pay attention to the human body and office and household appliances distance, the use of various electrical appliances, should maintain a certain safety distance, the farther away from the appliances, by electromagnetic wave infringement is smaller. Such as color TV and human distance should be 4 to 5 meters, and fluorescent tubes distance should be 2 to 3 meters, microwave ovens to leave at least 1 meter away after opening, pregnant women and children should try to stay away from microwave ovens. Conditional units and individuals can be equipped with anti-radiation clothing, computer, TV radiation screen, radiation curtains, radiation glass and other measures to reduce electromagnetic radiation, according to the concept of "one more point of protection, one less point of harm", rather than believe that there is, can not believe that there is nothing to do to prevent or not.