What is radiation and ionizing radiation? What is radiation.

What is radiation?
The term "radiation" comes from Lat. radius is a ray, and in the broadest sense it covers all types of radiation in general. Visible light and radio waves are also, strictly speaking, radiation, but by radiation we usually mean only ionizing radiation, that is, those whose interaction with matter leads to the formation of ions in it.
There are several types of ionizing radiation:
- alpha radiation - is a stream of helium nuclei
- beta radiation - a flow of electrons or positrons
- gamma radiation - electromagnetic radiation with a frequency of about 10^20 Hz.
— X-ray radiation is also electromagnetic radiation with a frequency of the order of 10^18 Hz.
- neutron radiation - neutron flux.

What is alpha radiation?
These are heavy positively charged particles consisting of two protons and two neutrons tightly bound together. In nature, alpha particles arise from the decay of atoms of heavy elements such as uranium, radium and thorium. In the air, alpha radiation travels no more than five centimeters and, as a rule, is completely blocked by a sheet of paper or the outer dead layer of skin. However, if a substance that emits alpha particles enters the body through food or inhaled air, it irradiates internal organs and becomes potentially dangerous.

What is beta radiation?
Electrons or positrons, which are much smaller than alpha particles and can penetrate several centimeters deep into the body. You can protect yourself from it with a thin sheet of metal, window glass, and even ordinary clothing. When beta radiation reaches unprotected areas of the body, it usually affects the upper layers of the skin. If a substance that emits beta particles enters the body, it will irradiate internal tissues.

What is neutron radiation?
Flow of neutrons, neutrally charged particles. Neutron radiation is produced during the fission of an atomic nucleus and has a high penetrating ability. Neutrons can be stopped by a thick concrete, water or paraffin barrier. Fortunately, in peaceful life, there is practically no neutron radiation anywhere except in the immediate vicinity of nuclear reactors.

What is gamma radiation?
An electromagnetic wave that carries energy. In the air it can travel long distances, gradually losing energy as a result of collisions with atoms of the medium. Intense gamma radiation, if not protected from it, can damage not only the skin, but also internal tissues.

What type of radiation is used in fluoroscopy?
X-ray radiation is electromagnetic radiation with a frequency of about 10^18 Hz.
Occurs when electrons moving at high speeds interact with matter. When electrons collide with atoms of any substance, they quickly lose their kinetic energy. In this case, most of it turns into heat, and a small fraction, usually less than 1%, is converted into X-ray energy.
In relation to X-ray and gamma radiation, the definitions “hard” and “soft” are often used. This is a relative characteristic of its energy and the associated penetrating power of radiation: “hard” - greater energy and penetrating ability, “soft” - less. X-ray radiation is soft, gamma radiation is hard.

Is there a place without radiation at all?
Hardly ever. Radiation is an ancient environmental factor. There are many natural sources of radiation: these are natural radionuclides contained in the earth's crust, building materials, air, food and water, as well as cosmic rays. On average, they account for more than 80% of the annual effective dose received by the population, mainly due to internal exposure.

What is radioactivity?
Radioactivity is the property of atoms of an element to spontaneously transform into atoms of other elements. This process is accompanied by ionizing radiation, i.e. radiation.

How is radiation measured?
Given that “radiation” itself is not a measurable quantity, there are various units for measuring various types radiation and pollution.
The concepts of absorbed, exposure, equivalent and effective dose, as well as the concept of equivalent dose rate and background are used separately.
In addition, for each radionuclide (radioactive isotope of an element), the activity of the radionuclide, the specific activity of the radionuclide, and the half-life are measured.

What is absorbed dose and how is it measured?
Dose, absorbed dose (from Greek - share, portion) - determines the amount of ionizing radiation energy absorbed by the irradiated substance. Characterizes the physical effect of radiation in any environment, including biological tissue, and is often calculated per unit mass of this substance.
It is measured in units of energy that is released in a substance (absorbed by the substance) when ionizing radiation passes through it.
Units of measurement are rad, gray.
Rad (rad – short for radiation absorbed dose) is a non-systemic unit of absorbed dose. Corresponds to a radiation energy of 100 erg absorbed by a substance weighing 1 gram
1 rad = 100 erg/g = 0.01 J/kg = 0.01 Gy = 2.388 x 10-6 cal/g
With an exposure dose of 1 roentgen, the absorbed dose in air will be 0.85 rad (85 erg/g).
Gray (Gr.) is a unit of absorbed dose in the SI system of units. Corresponds to 1 J of radiation energy absorbed by 1 kg of substance.
1 Gr. = 1 J/kg = 104 erg/g = 100 rad.

What is exposure dose and how is it measured?
The exposure dose is determined by the ionization of air, that is, by the total charge of ions formed in the air when ionizing radiation passes through it.
Units of measurement are roentgen, pendant per kilogram.
Roentgen (R) is a non-systemic unit of exposure dose. This is the amount of gamma or x-ray radiation that in 1 cm3 of dry air (which under normal conditions weighs 0.001293 g) forms 2.082 x 109 ion pairs. When converted to 1 g of air, this will be 1.610 x 1012 ion pairs or 85 erg/g of dry air. Thus, the physical energy equivalent of a roentgen is 85 erg/g for air.
1 C/kg is a unit of exposure dose in the SI system. This is the amount of gamma or x-ray radiation that in 1 kg of dry air forms 6.24 x 1018 pairs of ions that carry a charge of 1 coulomb of each sign. The physical equivalent of 1 C/kg is equal to 33 J/kg (for air).
The relationships between X-rays and C/kg are as follows:
1 P = 2.58 x 10-4 C/kg - exactly.
1 C/kg = 3.88 x 103 R - approx.

What is an equivalent dose and how is it measured?
The equivalent dose is equal to the absorbed dose calculated for a person taking into account coefficients that take into account the different ability of different types of radiation to damage body tissue.
For example, for x-ray, gamma, beta radiation, this coefficient (it is called the radiation quality factor) is 1, and for alpha radiation - 20. That is, with the same absorbed dose, alpha radiation will cause 20 times more harm to the body than, for example, gamma radiation.
Units of measurement are rem and sievert.
The rem is the biological equivalent of a rad (formerly an x-ray). Non-systemic unit of measurement of equivalent dose. In general:
1 rem = 1 rad * K = 100 erg/g * ​​K = 0.01 Gy * K = 0.01 J/kg * K = 0.01 Sievert,
where K is the radiation quality factor, see the definition of equivalent dose
For x-rays, gamma-rays, beta radiation, electrons and positrons, 1 rem corresponds to an absorbed dose of 1 rad.
1 rem = 1 rad = 100 erg/g = 0.01 Gy = 0.01 J/kg = 0.01 Sievert
Considering that with an exposure dose of 1 roentgen, air absorbs approximately 85 erg/g (physical equivalent of a roentgen), and biological tissue absorbs approximately 94 erg/g (biological equivalent of a roentgen), we can assume with minimal error that an exposure dose of 1 roentgen for biological tissue corresponds to an absorbed dose of 1 rad and an equivalent dose of 1 rem (for x-rays, gamma, beta radiation, electrons and positrons), that is, roughly speaking, 1 roentgen, 1 rad and 1 rem are the same thing.
Sievert (Sv) is the SI unit of equivalent and effective dose equivalent. 1 Sv is equal to the equivalent dose at which the product of the absorbed dose in Grays (in biological tissue) by the coefficient K will be equal to 1 J/kg. In other words, this is the absorbed dose at which 1 J of energy is released in 1 kg of substance.
In general:
1 Sv = 1 Gy * K = 1 J/kg * K = 100 rad * K = 100 rem * K
At K = 1 (for x-rays, gamma, beta radiation, electrons and positrons) 1 Sv corresponds to an absorbed dose of 1 Gy:
1 Sv = 1 Gy = 1 J/kg = 100 rad = 100 rem.

The effective equivalent dose is equal to the equivalent dose, calculated taking into account the different sensitivity of various organs of the body to radiation. The effective dose takes into account not only that different types of radiation have different biological effectiveness, but also that some parts of the human body (organs, tissues) are more sensitive to radiation than others. For example, at the same equivalent dose, lung cancer is more likely to occur than thyroid cancer. Thus, the effective dose reflects the total effect of human exposure in terms of long-term consequences.
To calculate the effective dose, the equivalent dose received by a specific organ or tissue is multiplied by the appropriate coefficient.
For the whole organism this coefficient is equal to 1, and for some organs it has the following values:
bone marrow (red) - 0.12
thyroid gland - 0.05
lungs, stomach, large intestine - 0.12
gonads (ovaries, testes) - 0.20
leather - 0.01
To estimate the total effective equivalent dose received by a person, the indicated doses for all organs are calculated and summed.
The unit of measurement is the same as that of the equivalent dose - “rem”, “sievert”

What is equivalent dose rate and how is it measured?
The dose received per unit time is called dose rate. The higher the dose rate, the faster the radiation dose increases.
For equivalent dose in SI, the dose rate unit is sievert per second (Sv/s), the non-system unit is rem per second (rem/s). In practice, their derivatives are most often used (μSv/hour, mrem/hour, etc.)

What is background, natural background, and how are they measured?
Background is another name for the exposure dose rate of ionizing radiation in a given location.
Natural background is the exposure dose rate of ionizing radiation in a given location, created only by natural radiation sources.
The units of measurement are rem and sievert, respectively.
Often the background and natural background are measured in roentgens (micro-roentgens, etc.), approximately equating roentgens and rem (see the question about equivalent dose).

What is radionuclide activity and how is it measured?
The amount of radioactive substance is measured not only in units of mass (gram, milligram, etc.), but also by activity, which is equal to the number of nuclear transformations (decays) per unit of time. The more nuclear transformations the atoms of a given substance undergo per second, the higher its activity and the greater the danger it can pose to humans.
The SI unit of activity is decays per second (dec/s). This unit is called the becquerel (Bq). 1 Bq equals 1 dis/s.
The most commonly used extra-systemic unit of activity is the curie (Ci). 1 Ci equals 3.7 * 10 in 10 Bq, which corresponds to the activity of 1 g of radium.

What is the specific surface activity of a radionuclide?
This is the activity of a radionuclide per unit area. Typically used to characterize the radioactive contamination of an area (radioactive contamination density).
Units of measurement - Bq/m2, Bq/km2, Ci/m2, Ci/km2.

What is half-life and how is it measured?
Half-life (T1/2, also denoted by the Greek letter “lambda”, half-life) is the time during which half of the radioactive atoms decay and their number decreases by 2 times. The value is strictly constant for each radionuclide. The half-lives of all radionuclides are different - from fractions of a second (short-lived radionuclides) to billions of years (long-lived).
This does not mean that after a time equal to two T1/2 the radionuclide will decay completely. After T1/2 the radionuclide will become twice as small, after 2*T1/2 it will be four times less, etc. Theoretically, a radionuclide will never decay completely.

Limits and norms of exposure

(how and where can I get irradiated and what will happen to me for this?)

Is it true that when flying on an airplane you can get an additional dose of radiation?
In general, yes. Specific figures depend on the flight altitude, type of aircraft, weather and route; the background in the aircraft cabin can be approximately estimated as 200-400 µR/H.

Is it dangerous to do fluorography or radiography?
Although the image takes only a fraction of a second, the radiation power is very high and the person receives a sufficient dose of radiation. It’s not for nothing that the radiologist hides behind a steel wall when taking pictures.
Approximate effective doses for irradiated organs:
fluorography in one projection - 1.0 mSv
X-ray of the lungs - 0.4 m3
photograph of the skull in two projections - 0.22 mSv
dental image – 0.02 mSv
photograph of the nose (maxillary sinuses) - 0.02 mSv
image of the lower leg (legs due to a fracture) - 0.08 mSv
The indicated figures are correct for one image (unless specifically noted), with a working X-ray machine and the use of protective equipment. For example, when taking pictures of the lungs, it is not at all necessary to irradiate the head and everything below the waist. Demand a leaded apron and collar, they should give you one. The dose received during the examination must be recorded in the patient’s personal card.
And finally, any doctor who sends you for an x-ray must evaluate the risk of excess radiation compared to how much your images will help him for more effective treatment.

Radiation at industrial sites, landfills, abandoned buildings?

Radiation sources can be found anywhere, even in a residential building, for example. once used Radioisotope smoke detectors (RSD), which used isotopes emitting Alpha, Beta and Gamma radiation, all kinds of scales of devices produced before the 60s, on which paint was applied, which contained Radium-226 salts, were found in landfills gamma flaw detectors, test sources for dosimeters, etc.

Control methods and devices.

What instruments can measure radiation?
: The main instruments are a radiometer and a dosimeter. There are combined devices - dosimeter-radiometer. The most common are household dosimeters-radiometers: Terra-P, Pripyat, Sosna, Stora-Tu, Bella, etc. There are military devices such as DP-5, DP-2, DP-3, etc.

What is the difference between a radiometer and a dosimeter?
The radiometer shows the radiation dose rate here now and now. But to assess the effect of radiation on the body, it is not the power that is important, but the dose received.
A dosimeter is a device that, by measuring the radiation dose rate, multiplies it by the time of exposure to radiation, thereby calculating the equivalent dose received by the owner. Household dosimeters, as a rule, measure only the dose rate of gamma radiation (some also beta radiation), the weighting factor of which (radiation quality factor) is equal to 1.
Therefore, even if the device does not have a dosimeter function, the dose rate measured in R/h can be divided by 100 and multiplied by the irradiation time, thus obtaining the desired dose value in Sieverts. Or, which is the same thing, multiplying the measured dose rate by the irradiation time, we obtain the equivalent dose in rem.
A simple analogy - the speedometer in a car shows the instantaneous speed “radiometer” and the kilometer counter integrates this speed over time, showing the distance traveled by the car (“dosimeter”).

Deactivation.

Methods for decontaminating equipment
Radioactive dust on contaminated equipment is held by forces of attraction (adhesion); the magnitude of these forces depends on the properties of the surface and the environment in which the attraction occurs. The adhesion forces in air are much greater than in liquid. In the event of contamination of equipment covered with oily contaminants, the adhesion of radioactive dust is determined by the adhesion strength of the oily layer itself.
During decontamination, two processes occur:
· separation of radioactive dust particles from a contaminated surface;
· removing them from the surface of the object.

Based on this, decontamination methods are based either on the mechanical removal of radioactive dust (sweeping, blowing away, dust extraction) or on the use of physicochemical washing processes (washing off radioactive dust with detergent solutions).
Due to the fact that partial decontamination differs from complete decontamination only in the thoroughness and completeness of processing, the methods of partial and complete decontamination are almost the same and depend only on the availability of technical means of decontamination and decontamination solutions.

All decontamination methods can be divided into two groups: liquid and liquid-free. An intermediate method between them is the gas-droplet decontamination method.
Liquid methods include:
· washing off radioactive substances with decontaminating solutions, water and solvents (gasoline, kerosene, diesel fuel, etc.) using brushes or rags;
· washing off the radioactive substances with a jet of water under pressure.
When processing equipment using these methods, the detachment of radioactive substance particles from the surface occurs in a liquid medium, when the adhesion forces are weakened. Transportation of detached particles during their removal is also provided by liquid flowing from the object.
Since the speed of movement of the layer of liquid directly adjacent to the solid surface is very small, the speed of movement of dust particles, especially very small ones, completely buried in a thin boundary layer of liquid, is also low. Therefore, to achieve sufficient completeness of decontamination, it is necessary, simultaneously with the supply of liquid, to wipe the surface with a brush or rag, and to use solutions of detergents that facilitate tearing off radioactive contamination and holding them in solution, or using a powerful jet of water with high pressure and fluid flow per unit surface.
Liquid treatment methods are highly effective and versatile; almost all existing standard decontamination technical means are designed for liquid treatment methods. The most effective of them is the method of washing off the radioactive substances with decontaminating solutions using brushes (allows you to reduce the contamination of an object by 50 - 80 times), and the fastest in implementation is the method of washing off the radioactive substances with a stream of water. The method of washing off radioactive substances with decontamination solutions, water and solvents using rags is used mainly for decontamination of the internal surfaces of the car cabin, various devices sensitive to large volumes of water and decontamination solutions.
The choice of one or another liquid treatment method depends on the availability of decontaminating substances, the capacity of water sources, technical means and the type of equipment to be decontaminated.
Liquid-free methods include the following:
· sweeping away radioactive dust from the site with brooms and other auxiliary materials;
· removal of radioactive dust by dust extraction;
· blowing off radioactive dust with compressed air.
When implementing these methods, the separation of radioactive dust particles occurs in the air when the adhesion forces are high. Existing methods (dust extraction, air jet from a car compressor) cannot create a sufficiently powerful air flow. All these methods are effective in removing dry radioactive dust from dry, non-oily and not heavily contaminated objects. The standard technical means for decontaminating military equipment using a liquid-free method (dust extraction) is currently the DK-4 kit, which can be used to treat equipment using both liquid and liquid-free methods.
Liquid-free decontamination methods can reduce the contamination of objects:
· overcasting - 2 - 4 times;
· dust extraction - 5 - 10 times;
· blowing with compressed air from the car compressor - 2-3 times.
The gas-droplet method involves blowing an object with a powerful gas-droplet flow.
The source of the gas flow is an air-jet engine; at the exit from the nozzle, water is introduced into the gas flow, which is crushed into small droplets.
The essence of the method is that a film of liquid is formed on the surface being treated, due to which the adhesion forces of dust particles to the surface are weakened and a powerful gas flow blows them away from the object.
The gas-droplet decontamination method is carried out using heat machines (TMS-65, UTM), it eliminates manual labor when carrying out special processing of military equipment.
The decontamination time of a KamAZ vehicle with a gas-droplet flow is 1 - 2 minutes, water consumption is 140 liters, contamination is reduced by 50 - 100 times.
When decontaminating equipment using any liquid or liquid-free method, the following processing procedure must be followed:
· the object begins to be processed from upper parts, gradually falling down;
· consistently process the entire surface without skipping;
· treat each surface area 2-3 times, treat rough surfaces especially carefully with increased liquid consumption;
· when treating with solutions using brushes and rags, thoroughly wipe the surface to be treated;
· when treating with a stream of water, direct the stream at an angle of 30 - 60° to the surface, being 3 - 4 m from the object being treated;
· ensure that splashes and liquid flowing from the object being treated do not fall on people performing decontamination.

Behavior in situations of potential radiation hazard.

If I was told that a nuclear power plant exploded nearby, where should I run?
Don't run anywhere. Firstly, you could have been deceived. Secondly, in case of real danger, it is best to trust the actions of professionals. And in order to find out about these very actions, it is advisable to be at home, turn on the radio or TV. As a precautionary measure, it is recommended to tightly close windows and doors, do not let children and pets outside, and wet clean the apartment.

What medications should you take to prevent harm from radiation?
During accidents at nuclear power plants, a large amount of the radioactive isotope iodine-131 is released into the atmosphere, which accumulates in the thyroid gland, which leads to internal irradiation of the body and can cause thyroid cancer. Therefore, in the first days after contamination of the territory (or better before this contamination), it is necessary to saturate the thyroid gland with ordinary iodine, then the body will be immune to its radioactive isotope. Drinking iodine from a bottle is extremely harmful; there are various tablets - regular potassium iodide, iodine active, iodomarin, etc., all of them are the same potassium iodine.
If there is no potassium-iodine nearby, and the area is polluted, then, as a last resort, you can drop a couple of drops of regular iodine into a glass of water or jelly and drink.
The half-life of iodine-131 is just over 8 days. Accordingly, after two weeks you can, in any case, forget about taking iodine orally.

Radiation dose table.

Radioactivity is the instability of the nuclei of some atoms, which manifests itself in their ability to undergo spontaneous transformation (in scientific terms, decay), which is accompanied by the release of ionizing radiation (radiation). The energy of such radiation is quite high, so it is capable of influencing matter, creating new ions of different signs. Cause radiation using chemical reactions You can’t, it’s a completely physical process.

There are several types of radiation:

• Alpha particles- these are relatively heavy particles, positively charged, they are helium nuclei.
• Beta particles- ordinary electrons.
• Gamma radiation- has the same nature as visible light, however, much greater penetrating power.
• Neutrons- these are electrically neutral particles that arise mainly near an operating nuclear reactor; access there should be limited.
• X-rays- similar to gamma radiation, but have less energy. By the way, the Sun is one of the natural sources of such rays, but protection from solar radiation is provided by the Earth’s atmosphere.

The most dangerous radiation for humans is Alpha, Beta and Gamma radiation, which can lead to serious illnesses, genetic disorders and even death. The extent to which radiation affects human health depends on the type of radiation, time and frequency. Thus, the consequences of radiation, which can lead to fatal cases, occur both during a single stay at the strongest source of radiation (natural or artificial), and when storing weakly radioactive objects at home (antiques, precious stones treated with radiation, products made from radioactive plastic) . Charged particles are very active and interact strongly with matter, so even one alpha particle can be enough to destroy a living organism or damage a huge number of cells. However, for the same reason, any layer of solid or liquid substance, for example, ordinary clothing, is a sufficient means of protection against this type of radiation.

According to experts at www.site, ultraviolet radiation or laser radiation cannot be considered radioactive. What is the difference between radiation and radioactivity?

Sources of radiation are nuclear facilities (particle accelerators, reactors, X-ray equipment) and radioactive substances. They can exist for a considerable time without manifesting themselves in any way, and you may not even suspect that you are near an object of extreme radioactivity.

Units of measurement of radioactivity

Radioactivity is measured in Becquerels (BC), which corresponds to one decay per second. The content of radioactivity in a substance is also often estimated per unit of weight - Bq/kg, or volume - Bq/cub.m. Sometimes there is such a unit as Curie (Ci). This is a huge value, equal to 37 billion Bq. When a substance decays, the source emits ionizing radiation, the measure of which is the exposure dose. It is measured in Roentgens (R). 1 Roentgen is a fairly large value, so in practice a millionth (µR) or thousandth (mR) fraction of a Roentgen is used.

Household dosimeters measure ionization over a certain time, that is, not the exposure dose itself, but its power. The unit of measurement is micro-Roentgen per hour. It is this indicator that is most important for a person, as it allows one to assess the danger of a particular radiation source.

Radiation and human health

The effect of radiation on the human body is called irradiation. During this process, radiation energy is transferred to the cells, destroying them. Radiation can cause all sorts of diseases: infectious complications, metabolic disorders, malignant tumors and leukemia, infertility, cataracts and much more. Radiation has a particularly acute effect on dividing cells, so it is especially dangerous for children.

The body reacts to the radiation itself, and not to its source. Radioactive substances can enter the body through the intestines (with food and water), through the lungs (during breathing) and even through the skin during medical diagnostics using radioisotopes. In this case, internal exposure occurs. In addition, external radiation has a significant impact on the human body, i.e. The source of radiation is outside the body. The most dangerous, of course, is internal radiation.

How to remove radiation from the body? This question certainly worries many. Unfortunately, especially effective and quick ways There is no removal of radionuclides from the human body. Certain foods and vitamins help cleanse the body of small doses of radiation. But if the radiation exposure is serious, then we can only hope for a miracle. Therefore, it is better not to take risks. And if there is even the slightest danger of being exposed to radiation, it is necessary to move your feet away as quickly as possible. dangerous place and call specialists.

Is a computer a source of radiation?

This question, in the age of the spread of computer technology, worries many. The only part of the computer that could theoretically be radioactive is the monitor, and even then, only electro-beam. Modern displays, liquid crystal and plasma, do not have radioactive properties.

CRT monitors, like televisions, are a weak source of X-ray radiation. It appears on the inner surface of the glass of the screen, however, due to the significant thickness of the same glass, it absorbs most of the radiation. To date, no health effects have been found from CRT monitors. However, with the widespread use of liquid crystal displays, this issue is losing its former relevance.

Can a person become a source of radiation?

Radiation, affecting the body, does not form in it radioactive substances, i.e. a person does not turn into a source of radiation. By the way, X-rays, contrary to popular belief, are also safe for health. Thus, unlike a disease, radiation damage cannot be transmitted from person to person, but radioactive objects that carry a charge can be dangerous.

Radiation level measurement

You can measure the level of radiation using a dosimeter. Household appliances are simply irreplaceable for those who want to protect themselves as much as possible from the deadly effects of radiation. The main purpose of a household dosimeter is to measure the radiation dose rate in the place where a person is located, to examine certain objects (cargo, building materials, money, food, children's toys, etc.), which is simply necessary for those who often visit areas of radiation contamination caused by the accident at the Chernobyl nuclear power plant (and such outbreaks are present in almost all regions of the European territory of Russia). The dosimeter will also help those who are in an unfamiliar area, far from civilization: on a hike, picking mushrooms and berries, or hunting. It is imperative to inspect the site of the proposed construction (or purchase) of a house, cottage, garden or land plot for radiation safety, otherwise, instead of benefit, such a purchase will only bring deadly diseases.

It is almost impossible to clean food, soil or objects from radiation, so the only way to protect yourself and your family is to stay away from them. Namely, a household dosimeter will help identify potentially dangerous sources.

Radioactivity standards

Regarding radioactivity exists big number norms, i.e. They try to standardize almost everything. Another thing is that dishonest sellers, in pursuit of big profits, do not comply with, and sometimes even openly violate, the norms established by law. The basic standards established in Russia are prescribed in Federal Law No. 3-FZ of December 5, 1996 “On Radiation Safety of the Population” and in Sanitary Rules 2.6.1.1292-03 “Radiation Safety Standards”.

For inhaled air, water and food products are regulated by the content of both man-made (obtained as a result of human activity) and natural radioactive substances, which should not exceed the standards established by SanPiN 2.3.2.560-96.

In building materials The content of radioactive substances of the thorium and uranium family, as well as potassium-40, is normalized; their specific effective activity is calculated using special formulas. Requirements for building materials are also specified in GOST.

Indoors The total content of thoron and radon in the air is regulated: for new buildings it should be no more than 100 Bq (100 Bq/m 3), and for those already in use - less than 200 Bq/m 3. In Moscow, additional standards MGSN2.02-97 are also applied, which regulate the maximum permissible levels of ionizing radiation and radon content in building areas.

For medical diagnostics maximum dose values ​​are not indicated, but minimum requirements are put forward sufficient levels exposure to obtain high-quality diagnostic information.

IN computer technology The maximum radiation level for electro-ray (CRT) monitors is regulated. The X-ray dose rate at any point at a distance of 5 cm from a video monitor or personal computer should not exceed 100 µR per hour.

You can only check whether manufacturers comply with the statutory standards yourself, using a miniature household dosimeter. It is very simple to use, just press one button and check the readings on the liquid crystal display of the device with the recommended ones. If the norm is significantly exceeded, then this item poses a threat to life and health, and it should be reported to the Ministry of Emergency Situations so that it can be destroyed. Protect yourself and your family from radiation!

Radiation is a stream of particles produced during nuclear reactions or radioactive decay. We have all heard about the danger radioactive radiation for the human body and we know that it can cause a huge number of pathological conditions. But often most people do not know what exactly the dangers of radiation are and how they can protect themselves from it. In this article we looked at what radiation is, what its danger is to humans, and what diseases it can cause.

What is radiation

The definition of this term is not very clear to a person not connected with physics or, for example, medicine. The term “radiation” refers to the release of particles produced during nuclear reactions or radioactive decay. That is, this is radiation that comes out of certain substances.

Radioactive particles have different abilities to penetrate and pass through various substances . Some of them can pass through glass, the human body, and concrete.

Radiation protection rules are based on knowledge of the ability of specific radioactive waves to pass through materials. For example, the walls of X-ray rooms are made of lead, through which radioactive radiation cannot pass.

Radiation happens:

• natural. It forms the natural radiation background to which we are all accustomed. The sun, soil, stones emit radiation. They are not dangerous to the human body.
• technogenic, that is, one that was created as a result of human activity. This includes the extraction of radioactive substances from the depths of the Earth, the use of nuclear fuels, reactors, etc.

How radiation enters the human body

Acute radiation sickness

This condition develops with a single massive exposure to human radiation.. This condition is rare.

It can develop during some man-made accidents and disasters.

The degree of clinical manifestations depends on the amount of radiation affecting the human body.

In this case, all organs and systems can be affected.

Chronic radiation sickness

This condition develops with prolonged contact with radioactive substances.. Most often it develops in people who interact with them on duty.

However, the clinical picture may develop slowly over many years. With prolonged and prolonged contact with radioactive sources of radiation, damage occurs to the nervous, endocrine, circulatory systems. The kidneys also suffer, and failures occur in all metabolic processes.

Chronic radiation sickness has several stages. It can occur polymorphically, clinically manifested by damage to various organs and systems.

Oncological malignant pathologies

Scientists have proven that radiation can provoke cancer pathologies. Most often, skin or thyroid cancer develops; there are also frequent cases of leukemia, a blood cancer, in people suffering from acute radiation sickness.

According to statistics, the number of oncological pathologies after the accident at the Chernobyl nuclear power plant increased tens of times in areas affected by radiation.

Use of radiation in medicine

Scientists have learned to use radiation for the benefit of humanity. A huge number of different diagnostic and therapeutic procedures are related in one way or another to radioactive radiation. Thanks to sophisticated safety protocols and state-of-the-art equipment this use of radiation is practically safe for the patient and medical personnel, but subject to all safety rules.

Diagnostic medical techniques using radiation: radiography, computed tomography, fluorography.

Treatment methods include various types of radiation therapy, which are used in the treatment of oncological pathologies.

The use of radiation diagnostic methods and therapy should be carried out by qualified specialists. These procedures are prescribed to patients solely for indications.

Basic methods of protection against radiation radiation

Having learned to use radioactive radiation in industry and medicine, scientists took care of the safety of people who may come into contact with these dangerous substances.

Only careful adherence to the basics of personal prevention and protection from radiation can protect a person working in a dangerous radioactive zone from chronic radiation sickness.

Basic methods of protection against radiation:

• Protection through distance. Radioactive radiation has a certain wavelength, beyond which it has no effect. That's why in case of danger, you must immediately leave the danger zone.
• Shielding protection. The essence of this method is to use substances for protection that do not allow radioactive waves to pass through them. For example, paper, a respirator, and rubber gloves can protect against alpha radiation.
• Time protection. All radioactive substances have a half-life and decay time.
• Chemical protection. Substances that can reduce the negative effects of radiation on the body are given to a person orally or injected.

People working with radioactive substances have protocols for protection and behavior in various situations. Usually, dosimeters are installed in the work areas - devices for measuring background radiation.

Radiation is dangerous for humans. When its level increases above the permissible norm, various diseases and lesions develop internal organs and systems. Against the background of radiation exposure, malignant oncological pathologies can develop. Radiation is also used in medicine. It is used to diagnose and treat many diseases.

Radiation- invisible, inaudible, has no taste, color or smell, and is therefore terrible. Word " radiation»causes paranoia, terror, or a strange state strongly reminiscent of anxiety. With direct exposure to radiation, radiation sickness can develop (at this point, anxiety develops into panic, because no one knows what it is and how to deal with it). It turns out that radiation is deadly... but not always, sometimes even useful.

So what is it? What do they eat it with, this radiation, how to survive an encounter with it and where to call if it accidentally comes across you on the street?

What is radioactivity and radiation?

Radioactivity- instability of the nuclei of some atoms, manifested in their ability to undergo spontaneous transformations (decay), accompanied by the emission of ionizing radiation or radiation. Further we will talk only about the radiation that is associated with radioactivity.

Radiation, or ionizing radiation- these are particles and gamma quanta, the energy of which is high enough to create ions of different signs when exposed to matter. Radiation cannot be caused by chemical reactions.

What kind of radiation is there?

There are several types of radiation.

• Alpha particles: relatively heavy, positively charged particles that are helium nuclei.
• Beta particles- they're just electrons.
• Gamma radiation has the same electromagnetic nature as visible light, but has much greater penetrating power.
• Neutrons- electrically neutral particles arise mainly directly near an operating nuclear reactor, where access, of course, is regulated.
• X-ray radiation similar to gamma radiation, but has less energy. By the way, our Sun is one of the natural sources of X-ray radiation, but earth's atmosphere provides reliable protection against it.

Ultraviolet radiation And laser radiation in our consideration are not radiation.

Charged particles interact very strongly with matter, therefore, on the one hand, even one alpha particle, when entering a living organism, can destroy or damage many cells, but, on the other hand, for the same reason, sufficient protection from alpha and beta -radiation is any, even a very thin layer of solid or liquid substance - for example, ordinary clothing (if, of course, the radiation source is outside).

It is necessary to distinguish radioactivity And radiation. Sources of radiation - radioactive substances or nuclear technical installations (reactors, accelerators, X-ray equipment, etc.) - can exist for a considerable time, but radiation exists only until it is absorbed in any substance.

What can the effects of radiation on humans lead to?

The effect of radiation on humans is called exposure. The basis of this effect is the transfer of radiation energy to the cells of the body.
Irradiation may cause metabolic disorders, infectious complications, leukemia and malignant tumors, radiation infertility, radiation cataract, radiation burn, radiation sickness. The effects of radiation have a stronger effect on dividing cells, and therefore radiation is much more dangerous for children than for adults.

As for the frequently mentioned genetic(i.e., inherited) mutations as a consequence of human irradiation, such mutations have never been discovered. Even among the 78,000 children of Japanese survivors of the atomic bombings of Hiroshima and Nagasaki, no increase in the incidence of hereditary diseases was observed ( book “Life after Chernobyl” by Swedish scientists S. Kullander and B. Larson).

It should be remembered that much greater REAL damage to human health is caused by emissions from the chemical and steel industries, not to mention the fact that science does not yet know the mechanism of malignant degeneration of tissues from external influences.

How can radiation enter the body?

The human body reacts to radiation, not to its source.
Those sources of radiation, which are radioactive substances, can enter the body with food and water (through the intestines), through the lungs (during breathing) and, to a small extent, through the skin, as well as during medical radioisotope diagnostics. In this case we talk about internal training.
In addition, a person may be exposed to external radiation from a radiation source that is located outside his body.
Internal radiation is much more dangerous than external radiation.

Is radiation transmitted as a disease?

Radiation is created by radioactive substances or specially designed equipment. The radiation itself, acting on the body, does not form radioactive substances in it, and does not turn it into a new source of radiation. Thus, a person does not become radioactive after an X-ray or fluorographic examination. By the way, an X-ray image (film) also does not contain radioactivity.

An exception is the situation in which radioactive drugs are deliberately introduced into the body (for example, during a radioisotope examination of the thyroid gland), and the person becomes a source of radiation for a short time. However, drugs of this kind are specially selected so that they quickly lose their radioactivity due to decay, and the intensity of the radiation quickly decreases.

Of course " get dirty» body or clothing exposed to radioactive liquid, powder or dust. Then some of this radioactive “dirt” - along with ordinary dirt - can be transferred upon contact to another person. Unlike a disease, which, transmitted from person to person, reproduces its harmful force (and can even lead to an epidemic), the transmission of dirt leads to its rapid dilution to safe limits.

In what units is radioactivity measured?

Measure radioactivity serves activity. Measured in Becquerelach (Bk), which corresponds to 1 decay per second. The activity content of a substance is often estimated per unit weight of the substance (Bq/kg) or volume (Bq/cubic meter).
There is also such a unit of activity as Curie (Ki). This is a huge amount: 1 Ci = 37000000000 (37*10^9) Bq.
The activity of a radioactive source characterizes its power. So, in the source of activity 1 Curie occurs 37000000000 decays per second.

As mentioned above, during these decays the source emits ionizing radiation. The measure of the ionization effect of this radiation on a substance is exposure dose. Often measured in X-rays (R). Since 1 Roentgen is a rather large value, in practice it is more convenient to use the millionth ( mkr) or thousandth ( mR) fractions of Roentgen.
Action of common household dosimeters is based on measuring ionization over a certain time, that is, the exposure dose rate. Unit of measurement of exposure dose rate - microRoentgen/hour .

The dose rate multiplied by time is called dose. Dose rate and dose are related in the same way as the speed of a car and the distance traveled by this car (path).
To assess the impact on the human body, concepts are used equivalent dose And equivalent dose rate. Measured accordingly in Sievertach (Sv) And Sieverts/hour (Sv/hour). In everyday life we ​​can assume that 1 Sievert = 100 Roentgen. It is necessary to indicate which organ, part or entire body the dose was given to.

It can be shown that the above-mentioned point source with an activity of 1 Curie (for definiteness, we consider a cesium-137 source) at a distance of 1 meter from itself creates an exposure dose rate of approximately 0.3 Roentgen/hour, and at a distance of 10 meters - approximately 0.003 Roentgen/hour. Reducing dose rate with increasing distance always occurs from the source and is determined by the laws of radiation propagation.

Now the typical error of the funds is absolutely clear mass media, reporting: " Today, on such and such a street, a radioactive source of 10 thousand roentgens was discovered when the norm is 20».
Firstly, the dose is measured in Roentgens, and the source characteristic is its activity. A source of so many X-rays is the same as a bag of potatoes weighing so many minutes.
Therefore, in any case, we can only talk about the dose rate from the source. And not just the dose rate, but with an indication at what distance from the source this dose rate was measured.

Further, the following considerations can be made. 10 thousand roentgens/hour is quite a large value. It can hardly be measured with a dosimeter in hand, since when approaching the source, the dosimeter will first show both 100 Roentgen/hour and 1000 Roentgen/hour! It is very difficult to assume that the dosimetrist will continue to approach the source. Since dosimeters measure dose rate in micro-Roentgens/hour, it can be assumed that in this case we're talking about o 10 thousand micro-Roentgen/hour = 10 milli-Roentgen/hour = 0.01 Roentgen/hour. Such sources, although they do not pose a mortal danger, are less common on the street than hundred-ruble bills, and this can be a topic for an information message. Moreover, the mention of the “standard 20” can be understood as a conditional upper limit of the usual dosimeter readings in the city, i.e. 20 micro-Roentgen/hour.

Therefore, the correct message, apparently, should look like this: “Today, on such and such a street, a radioactive source was discovered, close to which the dosimeter shows 10 thousand micro-roentgens per hour, despite the fact that the average value of background radiation in our city does not exceed 20 micro-roentgens per hour "

What are isotopes?

There are more than 100 in the periodic table chemical elements. Almost each of them is represented by a mixture of stable and radioactive atoms which are called isotopes of this element. About 2000 isotopes are known, of which about 300 are stable.
For example, the first element of the periodic table - hydrogen - has the following isotopes:
hydrogen H-1 (stable)
deuterium H-2 (stable)
tritium N-3 (radioactive, half-life 12 years)

Radioactive isotopes are usually called radionuclides .

What is half-life?

The number of radioactive nuclei of the same type constantly decreases over time due to their decay.
The decay rate is usually characterized by a half-life: this is the time during which the number of radioactive nuclei certain type will decrease by 2 times.
Absolutely wrong is the following interpretation of the concept of “half-life”: “ if a radioactive substance has a half-life of 1 hour, this means that after 1 hour its first half will decay, and after another 1 hour the second half will decay, and this substance will completely disappear (disintegrate)«.

For a radionuclide with a half-life of 1 hour, this means that after 1 hour its amount will become 2 times less than the original, after 2 hours - 4 times, after 3 hours - 8 times, etc., but will never completely disappear. The radiation emitted by this substance will decrease in the same proportion. Therefore, it is possible to predict the radiation situation for the future if you know what and in what quantities of radioactive substances create radiation in a given place at a given time.

Everyone has it radionuclide- mine half life, it can range from fractions of a second to billions of years. It is important that the half-life of a given radionuclide is constant, and it is impossible to change it.
Formed by radioactive decay nuclei, in turn, can also be radioactive. For example, radioactive radon-222 owes its origin to radioactive uranium-238.

Sometimes there are statements that radioactive waste in storage facilities will completely disintegrate within 300 years. This is wrong. It’s just that this time will be approximately 10 half-lives of cesium-137, one of the most common man-made radionuclides, and over 300 years its radioactivity in waste will decrease almost 1000 times, but, unfortunately, will not disappear.

What is radioactive around us?

The following diagram will help to assess the impact on a person of certain sources of radiation (according to A.G. Zelenkov, 1990).

Based on its origin, radioactivity is divided into natural (natural) and man-made.

a) Natural radioactivity
Natural radioactivity has existed for billions of years and is literally everywhere. Ionizing radiation existed on Earth long before the origin of life on it and was present in space before the emergence of the Earth itself. Radioactive materials have been part of the Earth since its birth. Every person is slightly radioactive: in tissues human body One of the main sources of natural radiation is potassium-40 and rubidium-87, and there is no way to get rid of them.

Let's take into account that modern man spends up to 80% of his time indoors - at home or at work, where he receives the main dose of radiation: although buildings are protected from radiation from the outside, the building materials from which they are built contain natural radioactivity. Radon and its decay products make a significant contribution to human exposure.

b) Radon
The main source of this radioactive noble gas is Earth's crust. Penetrating through cracks and crevices in the foundation, floor and walls, radon lingers indoors. Another source of indoor radon is the building materials themselves (concrete, brick, etc.), which contain natural radionuclides that are a source of radon. Radon can also enter homes with water (especially if it is supplied from artesian wells), when burned natural gas etc.
Radon is 7.5 times heavier than air. As a result, radon concentrations in the upper floors of multi-story buildings are usually lower than on the ground floor.
A person receives the bulk of the radiation dose from radon while in a closed, unventilated room; Regular ventilation can reduce radon concentrations several times.
With prolonged exposure to radon and its products in the human body, the risk of lung cancer increases many times over.
The following diagram will help you compare the emission power of different radon sources.

c) Technogenic radioactivity
Man-made radioactivity arises as a result of human activity.
Conscious economic activity, during which the redistribution and concentration of natural radionuclides occurs, leads to noticeable changes in the natural radiation background. This includes mining and burning coal, oil, gas, other fossil fuels, use of phosphate fertilizers, mining and processing of ores.
For example, studies of oil fields in Russia show a significant excess of permissible radioactivity standards, an increase in radiation levels in the area of ​​wells caused by the deposition of radium-226, thorium-232 and potassium-40 salts on the equipment and adjacent soil. Operating and spent pipes are especially contaminated and often have to be classified as radioactive waste.
This type of transport, such as civil aviation, exposes its passengers increased exposure cosmic radiation.
And, of course, tests make their contribution nuclear weapons, nuclear energy and industrial enterprises.

Of course, accidental (uncontrolled) spread of radioactive sources is also possible: accidents, losses, thefts, spraying, etc. Such situations, fortunately, are VERY RARE. Moreover, their danger should not be exaggerated.
For comparison, the contribution of Chernobyl to the total collective dose of radiation that Russians and Ukrainians living in contaminated areas will receive in the next 50 years will be only 2%, while 60% of the dose will be determined by natural radioactivity.

What do commonly found radioactive objects look like?

According to MosNPO Radon, more than 70 percent of all cases of radioactive contamination detected in Moscow occur in residential areas with intensive new construction and green areas of the capital. It was in the latter that landfills were located in the 50-60s household waste, where low-level radioactive industrial waste, then considered relatively safe, was also transported.

In addition, individual objects shown below can be carriers of radioactivity:

	A switch with a glow-in-the-dark toggle switch, the tip of which is painted with a permanent light composition based on radium salts. Dose rate for point-blank measurements is about 2 milliRoentgen/hour

Is a computer a source of radiation?

The only part of the computer for which we can talk about radiation is the monitors on cathode ray tubes(CRT); This does not apply to displays of other types (liquid crystal, plasma, etc.).
Monitors, along with regular CRT televisions, can be considered a weak source of X-ray radiation originating from the inner surface of the glass of the CRT screen. However, due to the large thickness of this same glass, it also absorbs a significant part of the radiation. To date, no impact of X-ray radiation from CRT monitors on health has been discovered, however, all modern CRTs are produced with a conditionally safe level of X-ray radiation.

Currently, when it comes to monitors, the Swedish ones are generally recognized for all manufacturers. national standards "MPR II", "TCO-92", -95, -99. These standards, in particular, regulate electric and magnetic fields from monitors.
As for the term “low radiation”, this is not a standard, but just a declaration by the manufacturer that he has done something, known only to him, in order to reduce radiation. The less common term “low emission” has a similar meaning.

The standards in force in Russia are set out in the document “Hygienic requirements for personal electronic computers and organization of work” (SanPiN SanPiN 2.2.2/2.4.1340-03), the full text is located at the address, and a short excerpt about permissible values ​​of all types radiation from video monitors - here.

When fulfilling orders for radiation monitoring of the offices of a number of organizations in Moscow, LRK-1 employees carried out a dosimetric examination of about 50 CRT monitors of different brands, with screen diagonal sizes from 14 to 21 inches. In all cases, the dose rate at a distance of 5 cm from the monitors did not exceed 30 µR/hour, i.e. with a threefold reserve fit into permissible norm(100 microR/hour).

What is normal background radiation?

There are populated areas with increased background radiation. These are, for example, the highland cities of Bogota, Lhasa, Quito, where the level of cosmic radiation is approximately 5 times higher than at sea level.

These are also sandy zones with a high concentration of minerals containing phosphates with an admixture of uranium and thorium - in India (Kerala state) and Brazil (Espirito Santo state). We can mention the area where waters with a high concentration of radium come out in Iran (Romser). Although in some of these areas the absorbed dose rate is 1000 times higher than the average on the Earth's surface, population surveys have not revealed changes in the structure of morbidity and mortality.

In addition, even for a specific area there is no “normal background” as a constant characteristic; it cannot be obtained as a result of a small number of measurements.
In any place, even for undeveloped territories where “no human has set foot,” the radiation background changes from point to point, as well as at each specific point over time. These background fluctuations can be quite significant. In populated areas, additional factors of enterprise activity, transport operation, etc. are superimposed. For example, at airfields, thanks to the high-quality concrete pavement with granite crushed stone, the background is usually higher than in the surrounding area.

Measurements of radiation background in the city of Moscow allow us to indicate the TYPICAL value of the background on the street (open area) - 8 - 12 μR/hour, in room - 15 - 20 µR/hour.

What are the standards for radioactivity?

There are a lot of standards regarding radioactivity—literally everything is regulated. In all cases a distinction is made between the public and the staff, i.e. persons whose work involves radioactivity (nuclear power plant workers, nuclear industry workers, etc.). Outside of their production, personnel belong to the population. For personnel and production premises, their own standards are established.

Further we will talk only about the norms for the population - that part of them that is directly related to ordinary life activities, based on The federal law“On Radiation Safety of the Population” No. 3-FZ dated 05.12.96 and “Radiation Safety Standards (NRB-99). Sanitary rules SP 2.6.1.1292-03".

The main task of radiation monitoring (measurements of radiation or radioactivity) is to determine the compliance of the radiation parameters of the object under study (dose rate in the room, content of radionuclides in building materials, etc.) with established standards.

a) air, food and water
The content of both man-made and natural radioactive substances is standardized for inhaled air, water and food.
In addition to NRB-99, “Hygienic requirements for the quality and safety of food raw materials and food products(SanPiN 2.3.2.560-96).”

b) building materials
The content of radioactive substances from the uranium and thorium families, as well as potassium-40 (in accordance with NRB-99) is normalized.
Specific effective activity (Aeff) of natural radionuclides in building materials used for newly built residential and public buildings (class 1),
Aeff = АRa +1.31АTh + 0.085 Ak should not exceed 370 Bq/kg,
where АRa and АTh are the specific activities of radium-226 and thorium-232, which are in equilibrium with other members of the uranium and thorium families, Ak is the specific activity of K-40 (Bq/kg).
GOST 30108-94 “Construction materials and products. Determination of the specific effective activity of natural radionuclides" and GOST R 50801-95 "Wood raw materials, timber, semi-finished products and products from wood and wood materials. Permissible specific activity of radionuclides, sampling and methods for measuring specific activity of radionuclides.”
Note that according to GOST 30108-94, the value Aeff m is taken as the result of determining the specific effective activity in the controlled material and establishing the class of the material:
Aeff m = Aeff + DAeff, where DAeff is the error in determining Aeff.

c) premises
The total content of radon and thoron in indoor air is normalized:
for new buildings - no more than 100 Bq/m3, for those already in use - no more than 200 Bq/m3.
In the city of Moscow, MGSN 2.02-97 is used " Acceptable levels ionizing radiation and radon in built-up areas.”

d) medical diagnostics
There are no dose limits for patients, but there is a requirement for minimum sufficient exposure levels to obtain diagnostic information.

e) computer equipment
The exposure dose rate of X-ray radiation at a distance of 5 cm from any point on a video monitor or personal computer should not exceed 100 µR/hour. The standard is contained in the document “Hygienic requirements for personal electronic computers and organization of work” (SanPiN 2.2.2/2.4.1340-03).

How to protect yourself from radiation?

They are protected from the source of radiation by time, distance and substance.

• Time- due to the fact that the shorter the time spent near the radiation source, the lower the radiation dose received from it.
• Distance- due to the fact that radiation decreases with distance from the compact source (proportional to the square of the distance). If at a distance of 1 meter from the radiation source the dosimeter records 1000 μR/hour, then at a distance of 5 meters the readings will drop to approximately 40 μR/hour.
• Substance— you must strive to have as much matter as possible between you and the source of radiation: the more of it and the denser it is, the more of the radiation it will absorb.

Concerning main source exposure indoors - radon and its decay products, then regular ventilation allows to significantly reduce their contribution to the dose load.
In addition, if we are talking about building or decorating your own home, which is likely to last for more than one generation, you should try to buy radiation-safe building materials - fortunately, their range is now extremely rich.

Does alcohol help against radiation?

Alcohol taken shortly before exposure can, to some extent, reduce the effects of exposure. However, its protective effect is inferior to modern anti-radiation drugs.

When to think about radiation?

Always think. But in everyday life, the likelihood of encountering a radiation source that poses an immediate threat to health is extremely low. For example, in Moscow and the region, less than 50 such cases are recorded per year, and in most cases - thanks to the constant systematic work of professional dosimetrists (employees of the MosNPO "Radon" and the Central State Sanitary and Epidemiological System of Moscow) in the places where radiation sources and local radioactive contamination are most likely to be detected (landfills , pits, scrap metal warehouses).
Nevertheless, it is in everyday life that sometimes one should remember about radioactivity. It's useful to do this:

• when buying an apartment, house, land,
• when planning construction and finishing works,
• when choosing and purchasing building and finishing materials for an apartment or house
• when choosing materials for landscaping the area around the house (soil of bulk lawns, bulk coverings for tennis courts, paving slabs and paving stones, etc.)

It should still be noted that radiation is far from the most main reason for constant worry. According to the scale of relative danger of various types of anthropogenic impact on humans developed in the USA, radiation is at 26 - place, and the first two places are occupied heavy metals And chemical toxicants.

Radioactive radiation (or ionizing radiation) is energy that is released by atoms in the form of particles or waves of an electromagnetic nature. Humans are exposed to such exposure through both natural and anthropogenic sources.

The beneficial properties of radiation have made it possible to successfully use it in industry, medicine, scientific experiments and research agriculture and other areas. However, with the spread of this phenomenon, a threat to human health has arisen. A small dose of radioactive radiation can increase the risk of acquiring serious diseases.

The difference between radiation and radioactivity

Radiation, in a broad sense, means radiation, that is, the spread of energy in the form of waves or particles. Radioactive radiation is divided into three types:

• alpha radiation – flux of helium-4 nuclei;
• beta radiation – flow of electrons;
• Gamma radiation is a stream of high-energy photons.

The characteristics of radioactive radiation are based on their energy, transmission properties and the type of emitted particles.

Alpha radiation, which is a stream of corpuscles with a positive charge, can be delayed by thick air or clothing. This species practically does not penetrate the skin, but when it enters the body, for example, through cuts, it is very dangerous and has a detrimental effect on internal organs.

Beta radiation has more energy - electrons move at high speeds and are small in size. Therefore, this type of radiation penetrates through thin clothing and skin deep into the tissue. Beta radiation can be shielded using an aluminum sheet a few millimeters thick or a thick wooden board.

Gamma radiation is high-energy radiation of an electromagnetic nature that has a strong penetrating ability. To protect against it, you need to use a thick layer of concrete or a plate of heavy metals such as platinum and lead.

The phenomenon of radioactivity was discovered in 1896. The discovery was made by the French physicist Becquerel. Radioactivity is the ability of objects, compounds, elements to emit ionizing radiation, that is, radiation. The reason for the phenomenon is the instability of the atomic nucleus, which releases energy during decay. There are three types of radioactivity:

• natural – typical for heavy elements whose serial number is greater than 82;
• artificial – initiated specifically with the help of nuclear reactions;
• induced - characteristic of objects that themselves become a source of radiation if they are heavily irradiated.

Elements that are radioactive are called radionuclides. Each of them is characterized by:

• half-life;
• type of radiation emitted;
• radiation energy;
• and other properties.

Sources of radiation

The human body is regularly exposed to radioactive radiation. Approximately 80% of the amount received each year comes from cosmic rays. Air, water and soil contain 60 radioactive elements that are sources of natural radiation. Main natural source radiation is considered to be the inert gas radon, released from the earth and rocks. Radionuclides also enter the human body through food. Some of the ionizing radiation to which people are exposed comes from man-made sources, ranging from nuclear power generators and nuclear reactors to radiation used for medical treatment and diagnostics. Today, common artificial sources of radiation are:

• medical equipment (the main anthropogenic source of radiation);
• radiochemical industry (mining, enrichment nuclear fuel, nuclear waste processing and recovery);
• radionuclides used in agriculture and light industry;
• accidents at radiochemical plants, nuclear explosions, radiation emissions
• Construction Materials.

Based on the method of penetration into the body, radiation exposure is divided into two types: internal and external. The latter is typical for radionuclides dispersed in the air (aerosol, dust). They get on your skin or clothing. In this case, radiation sources can be removed by washing them away. External irradiation causes burns of mucous membranes and skin. In the internal type, the radionuclide enters the bloodstream, for example by injection into a vein or through a wound, and is removed by excretion or therapy. Such radiation provokes malignant tumors.

The radioactive background depends significantly on geographical location– in some regions, radiation levels can be hundreds of times higher than average.

The effect of radiation on human health

Radioactive radiation, due to its ionizing effect, leads to the formation of free radicals in the human body - chemically active aggressive molecules that cause cell damage and death.

Cells of the gastrointestinal tract, reproductive and hematopoietic systems are especially sensitive to them. Radioactive radiation disrupts their work and causes nausea, vomiting, bowel dysfunction, and fever. By affecting the tissues of the eye, it can lead to radiation cataracts. The consequences of ionizing radiation also include damage such as vascular sclerosis, deterioration of immunity, and damage to the genetic apparatus.

The system of transmission of hereditary data has a fine organization. Free radicals and their derivatives can disrupt the structure of DNA, the carrier of genetic information. This leads to mutations that affect the health of subsequent generations.

The nature of the effects of radioactive radiation on the body is determined by a number of factors:

• type of radiation;
• radiation intensity;
• individual characteristics of the body.

The effects of radioactive radiation may not appear immediately. Sometimes its consequences become noticeable after a significant period of time. Moreover, a large single dose of radiation is more dangerous than long-term exposure to small doses.

The amount of radiation absorbed is characterized by a value called Sievert (Sv).

• Normal background radiation does not exceed 0.2 mSv/h, which corresponds to 20 microroentgens per hour. When X-raying a tooth, a person receives 0.1 mSv.

• The lethal single dose is 6-7 Sv.

Application of ionizing radiation

Radioactive radiation is widely used in technology, medicine, science, military and nuclear industries and other areas of human activity. The phenomenon underlies devices such as smoke detectors, power generators, icing alarms, and air ionizers.

In medicine, radioactive radiation is used in radiation therapy to treat cancer. Ionizing radiation has made it possible to create radiopharmaceuticals. With their help, diagnostic examinations are carried out. Instruments for analyzing the composition of compounds and sterilization are built on the basis of ionizing radiation.

The discovery of radioactive radiation was, without exaggeration, revolutionary - the use of this phenomenon brought humanity to new level development. However, this also caused a threat to the environment and human health. In this regard, maintaining radiation safety is an important task of our time.