Scientific and technical progress is accompanied by a sharp increase in the power of electromagnetic fields (EMF) created by man, which in some cases are hundreds and thousands of times higher than the level of natural fields.
Range electromagnetic vibrations includes wavelengths from 1000 km to 0.001 µm and by frequency f from 3×10 2 to 3×10 20 Hz. The electromagnetic field is characterized by a set of vectors of electrical and magnetic components. Different ranges of electromagnetic waves have a common physical nature, but differ in energy, nature of propagation, absorption, reflection and effect on the environment and humans. The shorter the wavelength, the more energy the quantum carries.
The main characteristics of EMF are:
Electric field strength E, V/m.
Magnetic field strength N, A/m.
Energy flux density carried by electromagnetic waves I, W/m2.
The connection between them is determined by the dependence:
Energy connection I and frequencies f vibrations is defined as:
Where: f = s/l, a c = 3 × 10 8 m/s (speed of propagation of electromagnetic waves), h= 6.6 × 10 34 W/cm 2 (Planck’s constant).
In space. There are 3 zones surrounding the EMF source (Fig. 9):
A) Near zone(induction), where there is no wave propagation, no energy transfer, and therefore the electrical and magnetic components of EMF are considered independently. Zone R boundary< l/2p.
b) Intermediate zone(diffraction), where waves overlap each other, forming maxima and standing waves. Zone boundaries l/2p< R < 2pl. Основная характеристика зоны суммарная плотность потоков энергии волн.
V) Radiation zone(wave) with the boundary R > 2pl. There is wave propagation, therefore the characteristic of the radiation zone is the energy flux density, i.e. amount of energy incident per unit surface I(W/m2).
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Rice. 1.9. Zones of electromagnetic field existence
The electromagnetic field, as it moves away from the radiation sources, attenuates inversely proportional to the square of the distance from the source. In the induction zone the tension electric field decreases inversely with distance to the third power, and the magnetic field is inversely proportional to the square of the distance.
Based on the nature of their impact on the human body, EMFs are divided into 5 ranges:
Electro magnetic fields industrial frequency (EMF IF): f < 10 000 Гц.
Electromagnetic radiation in the radio frequency range (RF EMR) f 10,000 Hz.
Electromagnetic fields of the radio frequency part of the spectrum are divided into four subranges:
1) f from 10,000 Hz to 3,000,000 Hz (3 MHz);
2) f from 3 to 30 MHz;
3) f from 30 to 300 MHz;
4) f from 300 MHz to 300,000 MHz (300 GHz).
Sources of industrial-frequency electromagnetic fields are high-voltage power lines, open distribution devices, all electrical networks and devices powered by 50 Hz alternating current. The danger of exposure to lines increases with increasing voltage due to an increase in the charge concentrated on the phase. The electric field strength in areas where high-voltage power lines pass can reach several thousand volts per meter. Waves in this range are strongly absorbed by the soil and at a distance of 50-100 m from the line, the voltage drops to several tens of volts per meter. With systematic exposure to EP, functional disturbances in the activity of the nervous and cardiovascular systems are observed. With increasing field strength in the body, persistent functional changes occur in the central nervous system. Along with biological effect electric field between a person and a metal object, discharges can occur due to the body potential, which reaches several kilovolts if the person is isolated from the Earth.
Permissible levels of electric field strength at workplaces are established by GOST 12.1.002-84 “Electric fields of industrial frequency”. The maximum permissible level of EMF IF voltage is set at 25 kV/m. The permissible time spent in such a field is 10 minutes. Staying in an EMF IF with a voltage of more than 25 kV/m without protective equipment is not allowed, and staying in an EMF IF with a voltage of up to 5 kV/m is allowed throughout the entire working day. To calculate the permissible time of stay in the ED at voltages above 5 to 20 kV/m inclusive, the formula is used T = (50/E) - 2, where: T- permissible time of stay in the EMF IF, (hour); E- intensity of the electrical component of the EMF IF, (kV/m).
Sanitary standards SN 2.2.4.723-98 regulate the maximum permissible limits of the magnetic component of the EMF IF in the workplace. Magnetic component strength N should not exceed 80 A/m during an 8-hour stay in the conditions of this field.
The intensity of the electrical component of the EMF IF in residential buildings and apartments is regulated by SanPiN 2971-84 “Sanitary standards and rules for protecting the population from the effects of the electric field created by by air lines power transmission alternating current industrial frequency". According to this document, the value E should not exceed 0.5 kV/m inside residential premises and 1 kV/m in urban areas. The MPL standards for the magnetic component of EMF IF for residential and urban environments have not currently been developed.
RF EMR is used for heat treatment, metal smelting, radio communications, and medicine. The sources of EMF in industrial premises are lamp generators, in radio installations - antenna systems, in microwave ovens - energy leaks when the screen of the working chamber is damaged.
EMF RF exposure to the body causes polarization of atoms and molecules of tissues, orientation of polar molecules, the appearance of ionic currents in tissues, and heating of tissues due to the absorption of EMF energy. It breaks the structure electrical potentials, fluid circulation in the cells of the body, biochemical activity of molecules, blood composition.
The biological effect of RF EMR depends on its parameters: wavelength, intensity and mode of radiation (pulsed, continuous, intermittent), the area of the irradiated surface, and the duration of irradiation. Electromagnetic energy is partially absorbed by tissues and converted into heat, local heating of tissues and cells occurs. RF EMR has an adverse effect on the central nervous system, causing disturbances in neuroendocrine regulation, changes in the blood, clouding of the lens of the eyes (exclusively 4 subbands), metabolic disorders.
Hygienic standardization of RF EMR is carried out in accordance with GOST 12.1.006-84 “Electromagnetic fields of radio frequencies. Permissible levels at workplaces and requirements for monitoring.” EMF levels at workplaces are controlled by measuring the intensity of the electrical and magnetic components in the frequency range 60 kHz-300 MHz, and in the frequency range 300 MHz-300 GHz the energy flux density (PED) of EMF, taking into account the time spent in the irradiation zone.
For EMF radio frequencies from 10 kHz to 300 MHz, the strength of the electric and magnetic components of the field is regulated depending on the frequency range: the higher the frequencies, the lower the permissible value of the strength. For example, the electrical component of EMF for frequencies 10 kHz - 3 MHz is 50 V/m, and for frequencies 50 MHz - 300 MHz only 5 V/m. In the frequency range 300 MHz - 300 GHz, the radiation energy flux density and the energy load it creates are regulated, i.e. energy flow passing through a unit of irradiated surface during the action. Maximum value energy flux density should not exceed 1000 μW/cm2. The time spent in such a field should not exceed 20 minutes. Staying in the field in a PES equal to 25 μW/cm 2 is allowed during an 8-hour work shift.
In urban and domestic environment RF EMR regulation is carried out in accordance with SN 2.2.4/2.1.8-055-96 “Electromagnetic radiation in the radio frequency range”. In residential premises, the RF EMR PES should not exceed 10 μW/cm 2 .
In mechanical engineering, magnetic-pulse and electro-hydraulic processing of metals with a low-frequency pulse current of 5-10 kHz is widely used (cutting and crimping tubular blanks, stamping, cutting holes, cleaning castings). Sources pulse magnetic The fields at the workplace are open working inductors, electrodes, and current-carrying busbars. A pulsed magnetic field affects metabolism in brain tissue, endocrine systems regulation.
Electrostatic field(ESP) is a field of stationary electric charges interacting with each other. ESP is characterized by tension E, that is, the ratio of the force acting in the field on a point charge to the magnitude of this charge. ESP intensity is measured in V/m. ESPs arise in power plants, in electrotechnological processes. ESP is used in electrical gas cleaning and when applying paint and varnish coatings. ESP provides Negative influence on the central nervous system; workers in the zone develop ESP headache, sleep disturbance, etc. In ESP sources, in addition to biological effects, air ions pose a certain danger. The source of air ions is the corona that appears on the wires at voltage E>50 kV/m.
Acceptable tension levels ESPs are installed by GOST 12.1.045-84 “ Electrostatic fields. Permissible levels at workplaces and requirements for monitoring.” The permissible level of ESP tension is established depending on the time spent at the workplace. The ESP voltage level is set to 60 kV/m for 1 hour. When the ESP voltage is less than 20 kV/m, the time spent in the ESP is not regulated.
Main characteristics laser radiation are: wavelength l, (µm), radiation intensity, determined by the energy or power of the output beam and expressed in joules (J) or watts (W): pulse duration (sec), pulse repetition frequency (Hz) . The main criteria for the danger of a laser are its power, wavelength, pulse duration and radiation exposure.
According to the degree of danger, lasers are divided into 4 classes: 1 - output radiation is not dangerous to the eyes, 2 - direct and specularly reflected radiation is dangerous to the eyes, 3 - diffusely reflected radiation is dangerous to the eyes, 4 - diffusely reflected radiation is dangerous to the skin. .
The laser class according to the degree of danger of the generated radiation is determined by the manufacturer. When working with lasers, personnel are exposed to harmful and dangerous production factors.
To the group of physical harmful and hazardous factors when operating lasers include:
Laser radiation (direct, diffuse, specular or diffusely reflected),
Increased laser power supply voltage,
Dustiness of the air in the working area due to the products of interaction of laser radiation with the target, increased level ultraviolet and infrared radiation,
Ionizing and electromagnetic radiation in work area, increased brightness of light from pulsed pump lamps and the risk of explosion of laser pumping systems.
Personnel servicing lasers are exposed to hazardous chemicals and harmful factors, such as: ozone, nitrogen oxides and other gases due to the nature of the production process.
The effect of laser radiation on the body depends on the radiation parameters (power, wavelength, pulse duration, pulse repetition rate, irradiation time and irradiated surface area), localization of the effect and characteristics of the irradiated object. Laser radiation causes organic changes in the irradiated tissues (primary effects) and specific changes in the body itself (secondary effects). When exposed to radiation, rapid heating of the irradiated tissue occurs, i.e. thermal burn. As a result of rapid heating to high temperatures There is a sharp increase in pressure in the irradiated tissues, which leads to their mechanical damage. The effects of laser radiation on the body can cause functional disorders and even complete loss of vision. The nature of the damaged skin varies from mild to varying degrees burns, up to necrosis. In addition to tissue changes, laser radiation causes functional changes in the body.
Extremely permissible levels irradiation are regulated by “Sanitary norms and rules for the design and operation of lasers” 2392-81. The maximum permissible levels of irradiation are differentiated taking into account the operating mode of the lasers. For each operating mode, section of the optical range, the remote control value is determined using special tables. Dosimetric monitoring of laser radiation is carried out in accordance with GOST 12.1.031-81. When monitoring, the power density of continuous radiation, the energy density of pulsed and pulse-modulated radiation and other parameters are measured.
Ultraviolet radiation - This is electromagnetic radiation invisible to the eye, occupying an intermediate position between light and x-ray radiation. The biologically active part of UV radiation is divided into three parts: A with a wavelength of 400-315 nm, B with a wavelength of 315-280 nm and C 280-200 nm. UV rays have the ability to cause a photoelectric effect, luminescence, the development of photochemical reactions, and also have significant biological activity.
UV radiation is characterized bactericidal and erythemal properties. Erythemal radiation power - this is a quantity characterizing beneficial effect UV radiation per person. The unit of erythemal radiation is taken to be Er, corresponding to a power of 1 W for a wavelength of 297 nm. Unit of erythemal illumination (irradiance) Er per square meter(Er/m2) or W/m2. Radiation dose Ner is measured in Er×h/m 2, i.e. this is the irradiation of the surface for certain time. The bactericidal power of the UV radiation flux is measured in bact. Accordingly, the bactericidal irradiation is bact per m 2, and the dose is bact per hour per m 2 (bq × h/m 2).
Sources of UV radiation in production are electric arc, autogenous flame, mercury-quartz burners and other temperature emitters.
Natural UV rays have positive influence on the body. In case of shortage sunlight“light starvation” occurs, vitamin D deficiency, weakened immunity, functional disorders nervous system. At the same time, UV radiation from industrial sources can cause acute and chronic occupational eye diseases. Acute lesion eye is called electroophthalmia. Erythema of the skin of the face and eyelids is often detected. TO chronic lesions Chronic conjunctivitis, lens cataract, skin lesions (dermatitis, swelling with blistering) should be included.
Standardization of UV radiation carried out in accordance with “Sanitary standards for ultraviolet radiation in industrial premises” 4557-88. When normalizing, the radiation intensity is set in W/m 2. With an irradiation surface of 0.2 m2 for up to 5 minutes with a break of 30 minutes for a total duration of up to 60 minutes, the norm for UV-A is 50 W/m2, for UV-B 0.05 W/m2 and for UV -C 0.01 W/m2. At total duration irradiation of 50% of the work shift and a single irradiation of 5 min, the norm for UV-A is 10 W/m2, for UV-B 0.01 W/m2 with an irradiation area of 0.1 m2, and irradiation with UV-C not allowed.
An electromagnetic field is a type of matter that arises around moving charges. For example, around a conductor carrying current. The electromagnetic field consists of two components: electric and magnetic field. They cannot exist independently of each other. One thing begets another. When the electric field changes, a magnetic field immediately appears.
Electromagnetic wave propagation speed V=C/EM
Where e And m respectively magnetic and the dielectric constant environment in which the wave propagates.
An electromagnetic wave in a vacuum travels at the speed of light, that is, 300,000 km/s. Since the dielectric and magnetic permeability of a vacuum are considered equal to 1.
When the electric field changes, a magnetic field appears. Since the electric field that caused it is not constant (that is, it changes over time), the magnetic field will also be variable.
A changing magnetic field in turn generates an electric field, and so on. Thus, for the subsequent field (it does not matter whether it is electric or magnetic), the source will be the previous field, and not the original source, that is, a conductor with current.
Thus, even after turning off the current in the conductor, the electromagnetic field will continue to exist and spread in space.
An electromagnetic wave propagates in space in all directions from its source. You can imagine turning on a light bulb, the rays of light from it spread in all directions.
An electromagnetic wave, when propagating, transfers energy in space. The stronger the current in the conductor that causes the field, the greater the energy transferred by the wave. Also, the energy depends on the frequency of the emitted waves; if it increases by 2,3,4 times, the wave energy will increase by 4,9,16 times, respectively. That is, the energy of wave propagation is proportional to the square of the frequency.
The best conditions for wave propagation are created when the length of the conductor is equal to the wavelength.
The magnetic and electric lines of force will fly mutually perpendicular. Magnetic power lines cover the current-carrying conductor and are always closed.
Electrical lines of force go from one charge to another.
An electromagnetic wave is always transverse wave. That is, the lines of force, both magnetic and electric, lie in a plane perpendicular to the direction of propagation.
Electromagnetic field strength is a strength characteristic of the field. Also the tension vector quantity that is, it has a beginning and a direction.
The field strength is directed tangentially to the lines of force.
Since the electric and magnetic field strengths are perpendicular to each other, there is a rule by which the direction of wave propagation can be determined. When the screw rotates along the shortest path from the electric field strength vector to the magnetic field strength vector forward movement The screw will indicate the direction of wave propagation.
In 1860-1865 one of greatest physicists 19th century James Clerk Maxwell created a theory electromagnetic field. According to Maxwell, the phenomenon of electromagnetic induction is explained by in the following way. If at a certain point in space the magnetic field changes in time, then an electric field is also formed there. If there is a closed conductor in the field, then the electric field causes in it induced current. From Maxwell's theory it follows that it is also possible reverse process. If in a certain region of space the electric field changes with time, then a magnetic field is also formed there.
Thus, any change in the magnetic field over time gives rise to a changing electric field, and any change in the electric field over time gives rise to a changing magnetic field. These alternating electric and magnetic fields generating each other form a single electromagnetic field.
Properties of electromagnetic waves
The most important result that follows from the theory of the electromagnetic field formulated by Maxwell was the prediction of the possibility of the existence of electromagnetic waves. Electromagnetic wave- propagation of electromagnetic fields in space and time.
Electromagnetic waves, unlike elastic (sound) waves, can propagate in a vacuum or any other substance.
Electromagnetic waves in a vacuum propagate at speed c=299 792 km/s, that is, at the speed of light.
In matter, the speed of an electromagnetic wave is less than in a vacuum. The relationship between wavelength, its speed, period and frequency of oscillations obtained for mechanical waves are also fulfilled for electromagnetic waves:
Voltage vector fluctuations E and magnetic induction vector B occur mutually perpendicular planes and perpendicular to the direction of wave propagation (velocity vector).
An electromagnetic wave transfers energy.
Electromagnetic wave range
Around us complex world electromagnetic waves of various frequencies: radiation from computer monitors, cell phones, microwave ovens, televisions, etc. Currently, all electromagnetic waves are divided by wavelength into six main ranges.
Radio waves- these are electromagnetic waves (with a wavelength from 10000 m to 0.005 m), used to transmit signals (information) over a distance without wires. In radio communications, radio waves are created by high-frequency currents flowing in an antenna.
Electromagnetic radiation with a wavelength from 0.005 m to 1 micron, i.e. lying between the radio wave range and the range visible light, are called infrared radiation. Infrared radiation is emitted by any heated body. The sources of infrared radiation are stoves, batteries, electric lamps incandescent By using special devices infrared radiation can be converted to visible light and produce images of heated objects in complete darkness.
TO visible light include radiation with a wavelength of approximately 770 nm to 380 nm, from red to purple. The significance of this part of the spectrum of electromagnetic radiation in human life is extremely great, since a person receives almost all information about the world around him through vision.
Electromagnetic radiation with a wavelength shorter than violet, invisible to the eye, is called ultraviolet radiation. It can kill pathogenic bacteria.
X-ray radiation invisible to the eye. It passes without significant absorption through significant layers of a substance that is opaque to visible light, which is used to diagnose diseases of internal organs.
Gamma radiation called electromagnetic radiation emitted by excited nuclei and arising from the interaction of elementary particles.
Principle of radio communication
An oscillatory circuit is used as a source of electromagnetic waves. For effective radiation, the circuit is “opened”, i.e. create conditions for the field to “go” into space. This device is called open oscillatory circuit - antenna.
Radio communication is the transmission of information using electromagnetic waves, the frequencies of which are in the range from to Hz.
Radar (radar)
A device that transmits ultrashort waves and immediately receives them. Radiation is carried out in short pulses. The pulses are reflected from objects, allowing, after receiving and processing the signal, to establish the distance to the object.
Speed radar works on a similar principle. Think about how radar detects the speed of a moving car.
Electricity is all around us
Electromagnetic field (definition from TSB)- This special shape matter through which interaction between electrically charged particles occurs. Based on this definition, it is not clear what is primary - the existence of charged particles or the presence of a field. Perhaps only due to the presence of an electromagnetic field can particles receive a charge. Just like in the story with the chicken and the egg. The bottom line is that charged particles and the electromagnetic field are inseparable from each other and cannot exist without each other. Therefore, the definition does not give you and me the opportunity to understand the essence of the phenomenon of the electromagnetic field and the only thing that should be remembered is that it special form of matter! The electromagnetic field theory was developed by James Maxwell in 1865.
What is an electromagnetic field? One can imagine that we live in an electromagnetic Universe, which is entirely permeated by an electromagnetic field, and various particles and substances, depending on their structure and properties, under the influence of an electromagnetic field acquire a positive or negative charge, accumulate it, or remain electrically neutral. Respectively electromagnetic fields can be divided into two types: static, that is, emitted by charged bodies (particles) and integral to them, and dynamic, propagating in space, being separated from the source that emitted it. A dynamic electromagnetic field in physics is represented in the form of two mutually perpendicular waves: electric (E) and magnetic (H).
The fact that the electric field is generated by an alternating magnetic field field, and magnetic field - alternating electric, leads to the fact that electric and magnetic alternating fields do not exist separately from each other. The electromagnetic field of stationary or uniformly moving charged particles is directly related to the particles themselves. At accelerated movement of these charged particles, the electromagnetic field “breaks away” from them and exists independently in the form of electromagnetic waves, without disappearing when the source is removed.
Sources of electromagnetic fields
Natural (natural) sources of electromagnetic fields
Natural (natural) sources of EMF are divided into the following groups:
Earth's magnetic field. Magnitude geomagnetic field The earth is changing earth's surface from 35 µT at the equator to 65 µT near the poles.
Earth's electric field directed normally to the earth's surface, negatively charged relative to upper layers atmosphere. The electric field strength at the Earth's surface is 120...130 V/m and decreases approximately exponentially with height. Annual changes in EF are similar in nature throughout the Earth: maximum intensity is 150...250 V/m in January-February and minimum 100...120 V/m in June-July.
Atmospheric electricity - This electrical phenomena V earth's atmosphere. In the air (link) there are always positive and negative electrical charges - ions that arise under the influence of radioactive substances, cosmic rays and ultraviolet radiation from the Sun. Earth negatively charged; There is a large potential difference between it and the atmosphere. The electrostatic field strength increases sharply during thunderstorms. The frequency range of atmospheric discharges lies between 100 Hz and 30 MHz.
Extraterrestrial sources include radiation outside the Earth's atmosphere.
Biological electromagnetic background. Biological objects, like others physical bodies, at temperatures above absolute zero emit EMF in the range 10 kHz – 100 GHz. This is explained by the chaotic movement of charges - ions, in the human body. The power density of such radiation in humans is 10 mW/cm2, which for an adult gives a total power of 100 W. Human body also emits EMF at 300 GHz with a power density of about 0.003 W/m2.
Anthropogenic sources of electromagnetic fields
Anthropogenic sources are divided into 2 groups:
Sources of low-frequency radiation (0 - 3 kHz)
This group includes all systems for the production, transmission and distribution of electricity (power lines, transformer substations, power plants, various cable systems), home and office electrical and electronic equipment, including PC monitors, electric vehicles, railway transport and its infrastructure, as well as metro, trolleybus and tram transport.
Already today, the electromagnetic field on 18-32% of urban areas is formed as a result of automobile traffic. Electromagnetic waves generated during vehicle traffic interfere with television and radio reception and can also have harmful effects on the human body.
Sources of high-frequency radiation (from 3 kHz to 300 GHz)
This group includes functional transmitters - sources of electromagnetic fields for the purpose of transmitting or receiving information. These are commercial transmitters (radio, television), radiotelephones (car, radiotelephones, CB radio, amateur radio transmitters, industrial radiotelephones), directional radio communications (satellite radio communications, ground relay stations), navigation ( air service, shipping, radio point), locators (air traffic, shipping, transport locators, control over by air). This also includes various technological equipment using microwave radiation, alternating (50 Hz - 1 MHz) and pulsed fields, household equipment (microwave ovens), means of visually displaying information on cathode ray tubes (PC monitors, TVs, etc.) . For scientific research Ultra-high frequency currents are used in medicine. The electromagnetic fields that arise when using such currents pose a certain occupational hazard, so it is necessary to take measures to protect against their effects on the body.
The main technogenic sources are:
A peculiarity of exposure in urban conditions is the impact on the population of both the total electromagnetic background (integral parameter) and strong EMF from individual sources (differential parameter).
What is an electromagnetic field, how it affects human health and why it should be measured - you will learn from this article. Continuing to introduce you to the assortment of our store, we will tell you about useful devices - indicators of electromagnetic field strength (EMF). They can be used both in enterprises and at home.
What is an electromagnetic field?
The modern world is unthinkable without household appliances, mobile phones, electricity, trams and trolleybuses, televisions and computers. We are accustomed to them and do not think at all about the fact that any electrical device creates an electromagnetic field around itself. It is invisible, but affects any living organisms, including humans.
An electromagnetic field is a special form of matter that arises when moving particles interact with electric charges. The electric and magnetic fields are interrelated with each other and can generate one another - which is why, as a rule, they are spoken of together as one, electromagnetic field.
The main sources of electromagnetic fields include:
- power lines;
— transformer substations;
— electrical wiring, telecommunications, television and Internet cables;
— cell phone towers, radio and television towers, amplifiers, antennas for cell and satellite phones, Wi-Fi routers;
— computers, televisions, displays;
— household electrical appliances;
— induction and microwave ovens;
— electric transport;
— radars.
The influence of electromagnetic fields on human health
Electromagnetic fields affect any biological organisms- on plants, insects, animals, people. Scientists studying the effects of EMF on humans have concluded that prolonged and regular exposure to electromagnetic fields can lead to:
- increased fatigue, sleep disturbances, headaches, decreased blood pressure, decreased heart rate;
- disorders in the immune, nervous, endocrine, reproductive, hormonal, cardiovascular systems;
— development of oncological diseases;
— development of diseases of the central nervous system;
- allergic reactions.
EMF protection
There are sanitary standards that establish the maximum permissible levels of electromagnetic field strength depending on the time spent in danger zone- for residential premises, workplaces, places near sources strong field. If it is not possible to reduce radiation structurally, for example, from an electromagnetic transmission line (EMT) or a cell tower, then service instructions, protective equipment for working personnel, and sanitary quarantine zones of limited access are developed.
Various instructions regulate the time a person stays in the danger zone. Screening meshes, films, glazing, suits made of metallized fabric based on polymer fibers can reduce the intensity electromagnetic radiation a thousand times. At the request of GOST, EMF radiation zones are fenced off and provided with warning signs “Do not enter, dangerous!” and an electromagnetic field hazard sign.
Special services use instruments to constantly monitor the level of EMF intensity in workplaces and residential premises. You can take care of your health yourself by purchasing a portable device “Impulse” or a set “Impulse” + nitrate tester “SOEKS”.
Why do we need household electromagnetic field strength measuring devices?
The electromagnetic field negatively affects human health, so it is useful to know which places you visit (at home, in the office, in the garden, in the garage) may pose a danger. You must understand that increased electromagnetic background can be created not only by your electrical devices, telephones, televisions and computers, but also faulty wiring, neighbors’ electrical appliances, industrial facilities located nearby.
Experts have found that short-term exposure to EMF on a person is practically harmless, but long-term stay in an area with a high electromagnetic background is dangerous. These are the zones that can be detected using “Impulse” type devices. This way, you can check the places where you spend the most time; a nursery and your own bedroom; study. The device contains the values set regulatory documents, so you can immediately assess the degree of danger for you and your loved ones. It is possible that after the examination you will decide to move the computer away from the bed and get rid of cell phone with an amplified antenna, replace the old microwave oven with a new one, replace the insulation of the refrigerator door with No Frost mode.