Electromagnetic radiation in a broad sense includes non-ionizing radiation and ionizing radiation.
Non-ionizing radiation usually refers to radio waves, infrared rays, visible light, ultraviolet rays, etc. Ionizing radiation is the general name of all radiation that can cause ionization of matter when it passes through matter, including X-rays, α-rays, β-rays and γ-rays in electromagnetic waves.
First, the harm of non-ionizing radiation to human body
1, radio station. The main influence of strong radio waves on human body is neurasthenia syndrome, which is manifested as dizziness, insomnia and dreaminess, memory loss, palpitation, fatigue, emotional instability and other symptoms. The degree of its influence on human body depends on the magnetic field intensity, frequency, action time and the physical condition of workers. Once people are out of the electromagnetic field, the symptoms will be gradually alleviated or even eliminated.
2. Microwave oven. Microwave is more harmful to human body than medium and short wave. The degree of damage is also related to factors such as field strength, distance and irradiation time.
Different tissues and organs of human body have different sensitivities to microwaves, among which the eyes are the most sensitive and fragile. Workers exposed to high-intensity microwave for a long time can find that the lens of the eye is turbid and the retina falls off;
Effect on blood: the white blood cell count and platelet count in peripheral blood decreased;
Effects on nervous system and cardiovascular system: neurosis and autonomic nervous dysfunction. Such as headache, dizziness, fatigue, insomnia, dreaminess and memory loss; Bradycardia, blood pressure drop, palpitation, precordial pain and compression. The harm of microwave to human body has cumulative effect.
Preventive measures:
(1) Preventive hygiene evaluation and supervision of microwave transmission tower and communication base station construction project;
(2) shield the radiation source with good field source conductor.
(3) Strengthen the health education of employees and improve their awareness of self-protection;
(4) Strengthen health monitoring.
3. Infrared ray.
Exposure opportunities: outdoor work in the sun, naked fire, melting metal and glass, baking and other operations.
Harm to the body:
(1) Skin: Higher intensity infrared rays can raise the local temperature of the skin, dilate blood vessels, produce erythema effect, and cause pigmentation after repeated irradiation. Over-exposure can lead to acute skin burns, entering subcutaneous tissue and heating blood and deep tissue.
(2) Eyes: Infrared rays can cause cataracts in the eyes and burn the retina.
4. ultraviolet rays.
Exposure opportunity: When the temperature of the object is above 12000C, ultraviolet rays may appear in the radiation spectrum. With the increase of temperature, the wavelength of ultraviolet light becomes shorter and the intensity becomes larger. Electric welding, gas welding, electric furnace steelmaking, ultraviolet irradiation and other workplaces can be exposed to ultraviolet rays.
Harm to the body:
Ultraviolet rays can cause acute keratitis and skin erythema reaction, so workers engaged in electric welding suffer from electro-optic ophthalmia.
Precautions against ultraviolet radiation:
Use protective clothing and glasses that can absorb ultraviolet rays.
(2) The welding operation shall be equipped with movable barriers to enclose the operation area to prevent the spread of ultraviolet radiation. It is forbidden for probe eyes to look directly at ultraviolet emission sources such as arc light.
5. Laser
With the development of science and technology, the application of laser is increasingly extensive. Mainly used in industrial production such as drilling, welding, cutting, communication, laser holography and so on. Medically used in surgery. The harm of laser is mainly that the absorbed energy is converted into heat energy. Show in:
(l) damage to the skin. When laser irradiates the skin, it will cause skin burns. Thermal curing and even carbonization. It can also destroy blood vessels, red blood cells and brain tissue.
(2) Damage to eyes. Laser irradiation on the eyes will cause glare and blur the current force. Overexposure can cause retinal burns, decreased central vision, and even blindness.
Long-term low-dose and scattered laser irradiation may cause neurasthenia, fatigue after work, eye pain and other symptoms.
Preventive measures:
(1) Establish and improve safety operation procedures.
(2) Strengthen protective measures. The workplace should be decorated with light-absorbing and non-reflective materials, and the light source and light channel should have a hood.
(3) Personal protection. Laser operators should wear white work clothes and protective glasses.
Second, the harm of ionizing radiation to human body
1, the harm of ionizing radiation to human body:
No matter particle radiation or electromagnetic radiation, their optical quantum energy is very high. When they interact with organisms, they all interact with cells, tissues, body fluids and so on. Ionize the atoms or molecules of the tissue, thus directly destroying some macromolecular structures of the body. For example, the molecular chain of protein is destroyed, the molecular chain of ribonucleic acid is destroyed, and some enzymes that play an important role in metabolism are destroyed. In addition, for the active organism whose neuroendocrine system regulates and balances life, when neuroendocrine regulation is disturbed, the pathological changes of radiation injury are more serious.
Large doses of ionizing radiation in a short time can cause acute radiation sickness. Long-term excessive radiation can cause systemic diseases, such as dizziness, fatigue, loss of appetite, alopecia and other neurasthenia syndromes. High dose radiation will not only cause pathological changes in the body at that time, but also have long-term or genetic effects after the radiation stops, such as inducing cancer and dementia in children.
2. What factors affect the harm of electromagnetic radiation to human body?
Radiation intensity. The radiation intensity is high, which has serious harm and influence on human body.
(2) the frequency of the radiation field. The higher the frequency of the field, the greater the harm to human body.
(3) Radiation time and period. The longer the exposure time, the shorter the interval between two exposures, and the more serious the harm to human body.
(4) the temperature of the workplace. The higher the temperature in the workplace, the more serious the symptoms after human radiation. Therefore, strengthening ventilation and cooling in the workplace is one of the effective means to reduce the harm of electromagnetic waves to human body.
(5) Environmental humidity. The greater the humidity, the more serious the damage to the body after radiation.
(6) Wave oscillation, the adverse effects of pulse wave on human body are far greater than continuous wave.
(7) Age and gender. Children and women are more sensitive to electromagnetic radiation than others.
(8) differences in physical condition. Different people's constitutions have different induction to electromagnetic waves. Generally speaking, people who are weak are more sensitive to electromagnetic waves. After being affected by electromagnetic fields, the symptoms of discomfort are more obvious and stronger than normal people. People with chronic diseases and work contraindications are more sensitive to electromagnetic waves than ordinary people.
3, the basic method of radiation protection
In order to achieve the purpose of protection, according to the basic principle of dose limitation,
In order to reduce the internal and external radiation dose of all kinds of personnel, the following methods should be adopted:
(l) Controlling the quality and quantity of radiation sources is the way to radically cure radiation damage. On the premise of not affecting the application effect, the intensity, energy and toxicity of radiation sources should be reduced as much as possible.
(2) Reduce the irradiation time. The total dose of external irradiation is proportional to the total irradiation time, so the irradiation time must be reduced as much as possible. Measures such as reducing unnecessary residence time, rotating operation and improving operation technology can be taken to reduce individual exposure time.
(3) Strengthen shielding protection. Set a protective screen between the radioactive source and personnel to absorb or weaken the radiated energy. For X-ray and Y-ray, lead, iron, cement and brick can be selected as materials for the protective room; For Lu rays, aluminum, plexiglass, plastic and other materials can be used as protective screens; For neutron radiation, paraffin and boric acid materials can be used for protection.
(4) distance protection. The dose of point radioactive source is inversely proportional to the square of the distance. When operating, it should be as far away from the radioactive source as possible. It is forbidden to hold the radioactive source directly.
(5) Enclosure and isolation. For open sources and their workplaces, the method of "blockade and isolation" must be adopted to control open sources in a limited space to prevent them from spreading to the environment.
(6) decontamination and cleaning. When operating open radioactive sources and using open radioactive elements, it is necessary to clean up the pollution of working environment media at any time, monitor the pollution level and control the massive diffusion to the surrounding environment.
(7) Personal protection. Use personal protective equipment reasonably, such as masks, gloves, work shoes and hats, clothes, etc. Abide by personal protection rules, and prohibit all activities that may cause radioactive elements to invade the human body in an open radioactive workplace, such as drinking water, smoking, eating, making up, etc.
1, the intake of Chinese wolfberry food and pollen food should be increased. Lycium barbarum can nourish the liver and improve eyesight, and has the functions of protecting retina from light damage, scavenging free radicals and resisting X-ray radiation. Pollen contains a lot of biological nutrients such as nucleic acids, amino acids, vitamins, nicotinic acid and folic acid. Amino acids in pollen can improve the activity of peripheral blood granulocytes of irradiated animals, protect bone marrow, spleen and thymus, and increase SOD in blood.
2, control the heat computer family sedentary, reduce heat consumption. If the body can't use too much heat energy in its daily diet, it will turn into fat and lead to obesity. Therefore, we should control the intake of heat energy to maintain the standard weight. Improving memory and increasing the supply of high-quality protein can improve memory. Supplementing protein can make the brain in a better physiological state. We can choose more foods rich in protein, such as milk, fish, meat, eggs and poultry.
3. Eye protection Vitamin A and β -carotene are helpful for nourishing the liver and improving eyesight and relieving eye fatigue. Computer users stare at the screen for a long time, and the consumption of vitamin A increases, which affects their eyesight. Foods rich in vitamin A include milk, egg yolk, Monopterus albus and animal liver. Foods rich in carotene include carrots, green leafy vegetables, pumpkins and red sweet potatoes.
4, calming the nerves and supplementing calcium can soothe the nerves. Sitting in front of the computer for a long time is easy to cause mental irritability, and calcium supplementation can play a calming role. Foods rich in calcium, such as milk, yogurt, soybeans and their products, shrimp skin, kelp, fungus, sesame sauce, green leafy vegetables, etc.
5. Don't stay behind the computer. The location of the computer is very important. Try not to let the back of the screen face people, because the back of the computer has the strongest radiation, followed by the left and right sides, and the front of the screen has the weakest radiation.
6. Absorb electromagnetic waves with water. Maintain a good indoor working environment, such as comfortable temperature and clean air. Because water is the best medium to absorb electromagnetic waves, you can put more bottles of water around the computer. However, it must be plastic bottles and glass bottles. Never use a metal cup to hold water.
7. Wash your face and hands in time. There is a lot of static electricity on the surface of computer screen, and the accumulated dust can be transferred to the exposed parts of face and hands. After a long time, it is easy to appear rash and pigmentation, and even skin lesions in severe cases. So wash your face and hands in time after use.
In fact, in daily life, electromagnetic radiation is everywhere, so we should learn to protect ourselves actively. If we encounter radiation spots, don't confuse them. The simplest way to resist computer radiation is to pay attention to indoor ventilation and supplement nutrition.