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

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

The difference between radiation and radioactivity

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

• alpha radiation - a stream of helium-4 nuclei;
• beta radiation - the flow of electrons;
• gamma radiation is a stream of high-energy photons.

The characterization of radioactive emissions is based on their energy, transmission properties and the type of emitted particles.

Alpha radiation, which is a stream of positively charged corpuscles, can be blocked by 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 speed, and their size is small. Therefore, this type of radiation penetrates through thin clothing and skin deep into tissues. Shielding of beta radiation can be done with an aluminum sheet of a few millimeters or a thick wooden board.

Gamma radiation is a high-energy radiation of an electromagnetic nature, which has a strong penetrating power. To protect against it, you need to use a thick layer of concrete or a plate made 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 - the ability of objects, compounds, elements to emit ionizing study, 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 - characteristic of 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 strongly irradiated.

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

• half-life;
• the 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 annually comes from cosmic rays. Air, water and soil contain 60 radioactive elements that are sources natural radiation. The main natural source of radiation is the inert gas radon released from the ground and rocks. Radionuclides also enter the human body with food. Some of the ionizing radiation to which humans are exposed comes from anthropogenic sources, ranging from nuclear power generators and nuclear reactors to radiation used for medical treatment and diagnosis. To date, common artificial sources of radiation are:

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

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

The radioactive background significantly depends on geographical location- in some regions, the level of radiation can exceed the average by hundreds of times.

Effect of radiation on human health

Radioactive radiation due to the 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 exposure disrupts their work and causes nausea, vomiting, stool disorders, and fever. By acting on the tissues of the eye, it can lead to radiation cataracts. The consequences of ionizing radiation also include such damage as vascular sclerosis, impaired immunity, and a violation of 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 future generations.

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

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

The results of radiation exposure may not appear immediately. Sometimes its effects become noticeable after a considerable period of time. At the same time, a large single dose of radiation is more dangerous than long-term exposure to small doses.

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

• The normal radiation background 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 industry and other areas of human activity. The phenomenon underlies such devices as smoke detectors, power generators, icing alarms, air ionizers.

In medicine radiation used in radiation therapy for the treatment of cancer. Ionizing radiation allowed the creation of radiopharmaceuticals. They are used for diagnostic tests. On the basis of ionizing radiation, instruments for the analysis of the composition of compounds and sterilization are arranged.

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

What is radiation? How dangerous is radiation?

Radiation is a form of energy that comes from a specific source and travels through space. Sources can range from the sun, earth, rocks, to cars.

The energy they generate is commonly referred to as ionization radiation. Ionizing radiation is generated by unstable atoms, which have both energy and mass greater than stable atoms and can therefore cause damage.

Radiation can travel through space in the form of particles or waves. Particle radiation can be easily blocked by clothing, while wave radiation can be deadly and it can also pass through concrete.

Radiation is measured using Geiger counters and in the form of Sieverts (μSv).

How dangerous is radiation?

Each person receives a certain amount of radiation every day. Walking in the sun, getting an X-ray, going for a CT scan, going on a flight.

The problem is not radiation. The real issue is the amount of radiation or, in other words, the levels of radiation a person receives.

On average, a person receives 10 µSv per day and 3,600 µSv per year. A normal 5-hour 30-minute flight gives a dose of 40 µSv, while X-rays give a dose of 100 µSv.

All of these indicated doses are acceptable to the human body, but anything above 100,000 μSv can lead to disease and even death.

The risk of cancer increases the moment a person passes the 100,000 µSv level, and levels above 200,000 µSv are fatal.

Exposure to radiation

Radiation can damage the tissues of the human body, leading to burns, cancer, and even death.

Even high levels of sun exposure can cause sunburn as ultraviolet rays are a form of radiation.

A deeper note: radiation weakens or destroys the deoxyribonucleic acid (DNA) of the human body, causing an imbalance in the cells.

The imbalance then increases cell damage or kills them to the point where this process gives rise to life-threatening diseases such as cancer.

Children easily develop high levels of radiation because their cells are not strong enough to withstand the threat of radiation.

Incidents in the past, when radiation levels crossed the dreaded 200,000 µSv, noted for example in , and , have resulted in infant mortality and cancer.

What is alpha radiation and what is its danger?

Alpha radiation, also known as alpha decay, is a kind of radioactive decay in which a nuclear core discharges an alpha molecule and thus changes with a mass number that decreases by four and a nuclear number that decreases by two.

Alpha radiation is difficult to detect and measure. Even the most common devices, such as the CD V-700, are unable to detect alpha particles until beta radiation is received along with it.

High-tech devices capable of measuring alpha radiation require a professional training program, otherwise the layman will not be able to figure it out.

Moreover, because alpha radiation does not penetrate, it cannot be detected or measured by any device, even through a meager layer of water, blood, dust, paper, or other material.

There are two types of radiation: ionizing/non-ionizing and alpha radiation, which are classified as ionizing.

Ionizing is not as dangerous as non-ionizing due to the following reasons: alpha radiation cannot penetrate the skin, and materials with alpha emissions can only be harmful to humans if the materials are inhaled, ingested or penetrated through open wounds.

Otherwise, alpha radiation will not be able to penetrate clothing.

What is beta radiation and what are its effects?

Beta radiation is the radiation that occurs when radioactive decay begins to release radioactive particles.

It is non-ionizing radiation and moves in the form of waves. Beta radiation is considered dangerous because it has the ability to penetrate any solid material such as walls.

Exposure to beta radiation may have delayed effects on the body such as cell growth or cellular damage.

Since the effects of the introduction of beta radiation are not rapid, and there is no real way to find out if the contact caused the aggressive impact, problems may appear after a few years.

Radiation- invisible, inaudible, has no taste, color and smell, and therefore terrible. Word " radiation» Causes paranoia, horror, or an incomprehensible state that strongly resembles 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 a meeting with it and where to call if it accidentally sticks on the street?

What is radioactivity and radiation?

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

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

What is the radiation?

There are several types of radiation.

• alpha particles: relatively heavy, positively charged particles that are helium nuclei.
• beta particles are just electrons.
• Gamma radiation has the same electromagnetic nature as visible light, but has a much greater penetrating power.
• Neutrons- electrically neutral particles, appear mainly in the immediate vicinity of a working nuclear reactor, where access, of course, is regulated.
• x-ray radiation similar to gamma rays, but lower in energy. By the way, our Sun is one of natural sources X-ray radiation, but the 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 it enters a living organism, can destroy or damage a lot of cells, but, on the other hand, for the same reason, sufficient protection against alpha and beta -radiation is any, even a very thin layer of solid or liquid matter - for example, ordinary clothing (unless, of course, the source of radiation is outside).

should be distinguished radioactivity and radiation. Radiation sources - radioactive substances or nuclear installations (reactors, accelerators, X-ray equipment, etc.) - can exist for a considerable time, and radiation exists only until it is absorbed in any substance.

What can be the effect of radiation on a person?

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

As for the frequently mentioned genetic(i.e., inherited) mutations as a result of human exposure, these have never been found. Even among the 78,000 children of those Japanese who survived the atomic bombing of Hiroshima and Nagasaki, no increase in the number of cases of hereditary diseases was ascertained ( the book "Life after Chernobyl" by Swedish scientists S. Kullander and B. Larson).

It should be remembered that much more REAL damage to people's health is caused by emissions from the chemical and steel industries, not to mention the fact that science still does not 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 in medical radioisotope diagnostics. In this case, we talk about internal learning.
In addition, a person may be exposed to external radiation from a source of radiation that is outside their body.
Internal exposure is much more dangerous than external exposure.

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 in it radioactive substances, 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 (film) also does not carry radioactivity.

An exception is a situation in which radioactive preparations are intentionally introduced into the body (for example, during a radioisotope examination of the thyroid gland), and a person becomes a source of radiation for a short time. However, preparations of this kind are specially chosen so as to quickly lose their radioactivity due to decay, and the intensity of the radiation falls off quickly.

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

What is the unit of measure for radioactivity?

measure radioactivity serves activity. measured in becquerels (Bq), which corresponds to 1 decay per second. The content of activity in a substance is often estimated per unit weight of the substance (Bq/kg) or volume (Bq/m3).
There is also such a unit of activity as Curie (Key). This is a huge one: 1 Ki = 37000000000 (37*10^9) Bq.
The activity of a radioactive source characterizes its power. So, in the source of activity 1 Curie occurs 37000000000 disintegrations per second.

As mentioned above, during these decays, the source emits ionizing radiation. The measure of the ionization effect of this radiation on matter 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 a millionth ( mcr) or thousandth ( mr) fractions of Roentgen.
The action of common household dosimeters is based on the measurement of ionization over a certain time, that is, the exposure dose rate. The unit of measurement of the exposure dose rate is micro-roentgen/hour .

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

It can be shown that the above-mentioned point source with an activity of 1 Curie (for definiteness, we consider a source of caesium-137) 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. Decrease in dose rate with increasing distance always occurs from the source and is due to the laws of radiation propagation.

Now it's completely clear typical mistake media reporting: Today, a radioactive source of 10 thousand roentgens was discovered on such and such a street at a rate of 20».
First, the dose is measured in Roentgens, and the characteristic of the source 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 indicating at what distance from the source this dose rate was measured.

Further, the following considerations can be made. 10,000 roentgens per hour is a fairly large value. With a dosimeter in hand, it can hardly be measured, 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 the dose rate in micro Roentgen/hour, it can be assumed that in this case we are talking about 10 thousand micro Roentgen/hour = 10 milliRoentgen/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 informational message. Moreover, the mention of the “norm 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, a radioactive source was discovered on such and such a street, close to which the dosimeter shows 10 thousand microroentgens per hour, while the average value of the radiation background in our city does not exceed 20 microroentgens per hour ".

What are isotopes?

There are more than 100 chemical elements in the periodic table. Almost each of them is represented by a mixture of stable and radioactive atoms who are called isotopes 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 H-3 (radioactive, half-life 12 years)

Radioactive isotopes are commonly referred to as radionuclides .

What is a half-life?

The number of radioactive nuclei of the same type is constantly decreasing in time due to their decay.
The decay rate is usually characterized by the half-life: this is the time during which the number of radioactive nuclei of a certain type decreases 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, and this substance will completely disappear (decay)«.

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. In the same proportion, the radiation emitted by this substance will also decrease. Therefore, it is possible to predict the radiation situation for the future, if you know which and in what quantity of radioactive substances create radiation in a given place at a given time.

Everyone has it radionuclide- mine half life, it can be both fractions of a second and billions of years. It is important that the half-life of a given radionuclide is constant, and it's impossible to change it.
The nuclei formed during radioactive decay, in turn, can also be radioactive. So, for example, radioactive radon-222 owes its origin to radioactive uranium-238.

Sometimes there are statements that radioactive waste in storage facilities will completely decay in 300 years. This is not true. 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 by 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).

By origin, radioactivity is divided into natural (natural) and man-made.

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

We 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 protect from radiation from 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 inert gas is the earth's crust. Penetrating through cracks and crevices in the foundation, floor and walls, radon lingers in the premises. Another source of indoor radon is the building materials themselves (concrete, brick, etc.) containing natural radionuclides that are a source of radon. Radon can also enter homes with water (especially if it is supplied from artesian wells), when natural gas is burned, etc.
Radon is 7.5 times heavier than air. As a result, the concentration of radon in the upper floors of multi-storey buildings is usually lower than on the first floor.
The main part of the radiation dose from radon is received by a person while in a closed, unventilated room; regular ventilation can reduce the concentration of radon by several times.
Long-term exposure to radon and its products in the human body greatly increases the risk of lung cancer.
The following chart will help you compare the radiation power of various radon sources.

c) Man-made radioactivity
Technogenic 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 the extraction and combustion of coal, oil, gas, and other fossil fuels, the use of phosphate fertilizers, the extraction and processing of ores.
So, for example, studies of oil fields in Russia show a significant excess of the permissible levels of radioactivity, an increase in radiation levels in the area of ​​wells caused by the deposition of radium-226, thorium-232 and potassium-40 salts on equipment and adjacent soil. Especially contaminated are operating and exhausted pipes, which often have to be classified as radioactive waste.
Such a mode of transport as civil aviation exposes its passengers to increased exposure to cosmic radiation.
And, of course, nuclear weapons tests, nuclear energy and industry enterprises make their contribution.

Of course, accidental (uncontrolled) spread of radioactive sources is also possible: accidents, losses, theft, spraying, etc. Such situations are, fortunately, VERY RARE. In addition, 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 territories 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 encountered radioactive objects look like?

According to the MosNPO Radon, more than 70 percent of all cases detected in Moscow radioactive contamination accounts for residential areas with intensive new construction and green areas of the capital. It was in the latter in the 1950s and 1960s that household waste dumps were located, where low-level industrial waste, which were then considered relatively safe, was also dumped.

In addition, the 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 light compound permanent action based on radium salts. Dose rate when measuring "point-blank" - about 2 milliroentgen / hour

Is the computer a source of radiation?

The only parts of a computer that can be referred to as radiation are the monitors on cathode ray tubes(CRT); displays of other types (liquid crystal, plasma, etc.) are not affected.
Monitors, along with conventional CRT televisions, can be considered as a weak source of X-ray radiation that occurs on the inner surface of the CRT screen glass. However, due to the large thickness of the same glass, it also absorbs a significant part of the radiation. So far, no effect of X-ray radiation from monitors on CRT on health has been found, however, all modern CRTs are produced with a conditionally safe level of X-ray radiation.

For monitors, the Swedish National Standards are now generally accepted by all manufacturers. "MPR II", "TCO-92", -95, -99. These standards, in particular, regulate electrical and magnetic fields from monitors.
As for the term "low radiation" (" low level emissions"), then this is not a standard, but merely a declaration by the manufacturer that he has done something known only to him in order to reduce the emission. The less common term "low emission" has a similar meaning.

The norms 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), full text located at the address, and a short excerpt about allowed values all types of radiation from video monitors - here.

When fulfilling orders for radiation monitoring of offices of a number of organizations in Moscow, LRC-1 employees conducted a dosimetric examination of about 50 CRT monitors of various brands, with a screen diagonal size of 14 to 21 inches. In all cases, the dose rate at a distance of 5 cm from the monitors did not exceed 30 μR/h, i.e. with a threefold margin was within the allowable rate (100 microR/h).

What is normal background radiation?

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

These are also sandy zones with a high concentration of minerals containing phosphates mixed with uranium and thorium - in India (Kerala state) and Brazil (Espirito Santo state). It is possible to mention the site of the outlet of waters with a high concentration of radium in Iran (the city of Romser). Although in some of these areas the absorbed dose rate is 1000 times higher than the average over the Earth's surface, the survey of the population did not reveal any shifts in the patterns of morbidity and mortality.

In addition, even for a particular 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 foot 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 habitable places, the factors of the activity of enterprises, the work of transport, etc. are additionally superimposed. For example, at airfields, due to high-quality concrete pavement with crushed granite, the background is usually higher than in the surrounding area.

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

What are the standards for radioactivity?

With regard to radioactivity, there are a lot of rules - literally everything is normalized. In all cases, a distinction is made between the population and the staff, i.e. persons whose work is related to radioactivity (workers of nuclear power plants, nuclear industry, etc.). Outside of their production, personnel refers to the population. For personnel and industrial premises, their own standards are established.

Further, we will only talk about the norms for the population - that part of them that is directly related to ordinary life, 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, the content of radionuclides in building materials, etc.) with the established standards.

a) air, food and water
For inhaled air, water and food, the content of both man-made and natural radioactive substances is normalized.
In addition to NRB-99, the 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 families of uranium and thorium, as well as potassium-40 (in accordance with NRB-99) is regulated.
Specific effective activity (Aeff) of natural radionuclides in building materials used for newly constructed residential and public buildings (class 1),
Aeff \u003d ARa + 1.31ATh + 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 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 the specific activity of radionuclides”.
Note that according to GOST 30108-94, the result of determining the specific effective activity in the controlled material and establishing the class of the material is taken as the value of Aeff m:
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 operation - no more than 200 Bq/m3.
In the city of Moscow, MGSN 2.02-97 "Permissible levels of ionizing radiation and radon in building sites" are applied.

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

e) computer equipment
The exposure dose rate of X-ray radiation at a distance of 5 cm from any point of the video monitor or personal computer should not exceed 100 μR/hour. The norm 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?

From the source of radiation are protected by time, distance and matter.

• by 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 the radiation decreases with distance from the compact source (in proportion 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- it is necessary to strive to have as much substance as possible between you and the source of radiation: the more it is and the denser it is, the greater part of the radiation it will absorb.

Concerning main source irradiation in rooms radon and its decay products, then regular airing allows to significantly reduce their contribution to the dose load.
In addition, if we are talking about building or finishing your own housing, which will probably last more than one generation, you should try to buy radiation-safe building materials - since their range is now extremely rich.

Does alcohol help with radiation?

Alcohol ingested shortly before exposure can, to some extent, mitigate 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, it is extremely unlikely to encounter a source of radiation that poses an immediate threat to health. 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 Service of Moscow) in places where sources of radiation and local radioactive contamination are most likely to be detected (landfills pits, scrap yards).
Nevertheless, it is in everyday life that one should sometimes remember about radioactivity. This is useful to do:

• 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 coatings for tennis courts, paving slabs and paving stones, etc.)

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

Ionizing radiation or radiation is harmful to health, everyone knows this. But what diseases occur under the influence of radiation, what dose can be safe for a person, and what can kill him?

Radiation is an invisible danger

Safe radiation dose

Where does a person receive doses of radiation? Do not forget about natural radiation. At different points on the planet, the background radiation can differ significantly. So, on the mountain peaks, the radiation is higher, because there the protective properties of the atmosphere are lower. Increased radiation can also be in places where there is a lot of dust and sand with thorium and uranium in the air.

What dose of radiation can be safe, maximum permissible, and the body will not suffer? It should not exceed 0.3-0.5 µSv per hour. But if you stay in this room for a short time, then the human body transfers radiation with a power of 10 μS per hour without harm to health, this is the maximum permissible level of radiation.

Dangerous dose of radiation

If the maximum permissible level of radiation is exceeded, changes occur in the body of the victim. How does radiation affect a person, what can be in the body under its influence? The table below shows the doses of radiation and their effects on humans.

Radiation dose (per year)	Impact on a person
0.05 mSv	Permissible level of radiation, which should be near nuclear facilities.
0.3 - 0.6 mSv	Emit artificial sources of radiation (medical devices)
3 mSv	radiate natural springs, norm
3 - 5 mSv	Received by miners at uranium mines
10 mSv	The maximum permissible level of radiation received by miners during the extraction of uranium
20 mSv	Maximum allowable level of penetrating radiation for people working with radiation
50 mSv	This is the permissible (lowest) level of exposure, after which oncological diseases already occur.
1 Sv (1000 mSv)	The consequences are not so serious. If the exposure is short, the body may react with a malaise that does not threaten human life. But after a few years, there is a chance of getting cancer.
2-10 Sv	Short-term exposure will lead to the development of radiation sickness, this is not a lethal dose, but the consequences can be serious: there may be a fatal outcome
10 Sv	Damaging radiation. This is a lethal dose that the human body cannot tolerate. Illness and death within a few weeks.

Diseases that appear due to radiation

There are chemical elements (plutonium, radium, uranium, etc.) that are capable of spontaneous transformations. They are accompanied by a stream of radiation. It was first discovered in radium, so it was called radioactive decay, and the radiation was radioactive. Another name for it is penetrating radiation.

The genetic consequences of penetrating radiation are poorly understood

Mutations

Scientists know that radiation causes mutations. Damaging radiation causes changes. But while the genetic implications of penetrating radiation mutations are poorly understood. The fact is that mutations make themselves felt only after generations, and it will take many hundreds of years for mutations to manifest themselves. And it is not clear whether their occurrence is due to radiation or whether mutations are caused by other reasons.

Also, the difficulty lies in the fact that most children with anomalies do not have time to be born, women have a spontaneous abortion, a child with abnormalities may not be born. Mutations are dominant (immediately make themselves felt), and recessive, which appear only if the father and mother of the child have the same mutant gene. Then mutations may not appear for several generations, or they may not affect the life of a person and his descendants at all.

After the tragedy in Hiroshima and Nagasaki, 27,000 children were studied. Their parents themselves felt the effects of significant doses of radiation. They found only two mutations in the body. And the same number of children whose father and mother were exposed to less severe radiation did not have a mutation at all. However, this still doesn't say anything. The study of the effect of radiation on humans, mutations began not so long ago, and perhaps other “surprises” await us.

Radiation sickness

It occurs either with a single strong exposure or with constant exposure to relatively small doses. The damaging radiation is dangerous for human life. This is the most common disease associated with penetrating radiation.

Leukemia

Leukemia is caused by penetrating radiation

Statistics show that penetrating radiation often becomes the cause of leukemia. Back in the 40s of the last century, they noticed that radiologists often died after leukemia, the body could not withstand the radiation. Later, the influence of penetrating radiation on the development of leukemia was confirmed by observations of the inhabitants of Hiroshima and Nagasaki.

This time there was no talk about the exact doses of radiation, they took approximate figures, focusing on the epicenter of the explosion and the symptoms of acute radiation injury. Only 5 years after the bombing, cases of leukemia began to be recorded. Examined 109 thousand people who survived the bombing:

• The group of irradiated (dose over 1 Gy) from 1950 to 1971 - 58 cases, which is 7 times more than the figure expected by scientists.
• The group of exposed (dose less than 1 Gy) - 64 people fell ill, although it was expected that 71.

In subsequent years, the number of cases decreased. The consequences in the form of leukemia are dangerous for people who have experienced radiation before the age of 15 years. Illness after penetrating radiation does not immediately make itself felt. Most often, 4-10 years pass after the damaging radiation has dealt its blow. There is no consensus on how much radiation causes such consequences, everyone gives different allowable doses (50, 100, 200 r). The pathogenesis of radiation leukemia is also not fully understood yet, but scientists are working in that direction and offer their theories.

Other cancers

Penetrating radiation affects the occurrence of cancer

Scientists are studying the effects of radiation on humans, including trying to understand whether penetrating radiation affects the occurrence of cancer. But it is impossible to talk about exact information, because scientists cannot conduct experiments on people. Experiments are being conducted with animals, but they cannot be used to judge how damaging radiation affects the human body. For the information to be reliable, it is important to comply with the following conditions.

• You need to know the amount of absorbed dose.
• It is necessary that the radiation evenly hit either the whole body or a specific organ.
• Examine the experimental group regularly, and do this for decades.
• There must be another "control" group of people so that the level of the disease can be compared.
• Both groups must include a huge number of people.

It is impossible to conduct such an experiment, so scientists have to study the consequences associated with exposure to penetrating radiation after accidental exposure. So far, the data obtained is inaccurate. So, scientists believe that there is no acceptable dose of penetrating radiation, any dose increases the risk of developing cancer and can cause this disease. Most often, people after penetrating radiation appear:

1. Leukemia is number one.
2. Mammary cancer. 10 out of 1000 women develop this condition.
3. Thyroid cancer. After irradiation, 10 out of 1000 people develop a disease. It is now curable, the mortality rate is very low.
4. The result of exposure is lung cancer. Information that penetrating radiation affects the frequency of occurrence of this disease, on the human body, appeared not only according to data collected after the bombing of Japan, but also after a survey of miners of uranium mines in Canada, the USA and Czechoslovakia.

Radiation is ionizing radiation that causes irreparable harm to everything around. People, animals and plants suffer. The biggest danger lies in the fact that it is not visible to the human eye, so it is important to know about its main properties and effects in order to protect yourself.

Radiation accompanies people throughout their lives. It is found in the environment as well as within each of us. The greatest impact is external sources. Many have heard about the accident at the Chernobyl nuclear power plant, the consequences of which are still encountered in our lives. People were not ready for such a meeting. This once again confirms that there are events in the world beyond the control of humanity.

Types of radiation

Not all chemicals are stable. In nature, there are certain elements, the nuclei of which are transformed, breaking up into separate particles with the release of a huge amount of energy. This property is called radioactivity. As a result of research, scientists discovered several types of radiation:

1. Alpha radiation is a stream of heavy radioactive particles in the form of helium nuclei that can cause the greatest harm surrounding. Fortunately, they are characterized by low penetrating power. AT airspace they extend only a couple of centimeters. In tissue, their range is fractions of a millimeter. Thus, external radiation does not pose a danger. You can protect yourself by using thick clothing or a piece of paper. But internal exposure is a formidable threat.
2. Beta radiation is a stream of light particles moving in the air for a couple of meters. These are electrons and positrons penetrating two centimeters into the tissue. It is harmful in contact with human skin. However, it gives a greater danger when exposed from the inside, but less than alpha. To protect against the influence of these particles, special containers, protective screens, a certain distance are used.
3. Gamma and X-rays are electromagnetic radiations penetrating the body through and through. Protective measures against such exposure include the creation of lead screens, the construction of concrete structures. The most dangerous of irradiations with external damage, as it affects the entire body.
4. Neutron radiation consists of a stream of neutrons that have a higher penetrating power than gamma. It is formed as a result of nuclear reactions occurring in reactors and special research facilities. Appears during nuclear explosions and is found in waste fuel from nuclear reactors. Armor from such an impact is created from lead, iron, concrete.

All radioactivity on Earth can be divided into two main types: natural and artificial. The first includes radiation from space, soil, gases. The artificial one appeared thanks to a person when using nuclear power plants, various equipment in medicine, nuclear enterprises.

natural sources

Radioactivity of natural origin has always been on the planet. Radiation is present in everything that surrounds humanity: animals, plants, soil, air, water. This small level of radiation is believed to have no harmful effects. However, some scholars are of a different opinion. Since people do not have the opportunity to influence this danger, circumstances that increase the allowable values ​​should be avoided.

Varieties of sources of natural origin

1. Cosmic radiation and solar radiation are the most powerful sources capable of eliminating all life on Earth. Fortunately, the planet is protected from this impact by the atmosphere. However, people have tried to correct this situation by developing activities that lead to the formation of ozone holes. Do not stay in direct sunlight for a long time.
2. Radiation earth's crust dangerous near deposits of various minerals. By burning coal or using phosphorus fertilizers, radionuclides actively seep into a person with the inhaled air and the food they eat.
3. Radon is radioactive chemical element present in building materials. It is a colorless, odorless and tasteless gas. This element actively accumulates in soils and goes outside along with mining. It enters apartments along with household gas, as well as with tap water. Fortunately, its concentration can be easily reduced by constantly ventilating the premises.

artificial sources

This species appeared thanks to people. Its effect is increased and spread with their help. During the start nuclear war the strength and power of weapons are not so terrible as the consequences of radioactive radiation after explosions. Even if you are not hooked by a blast wave or physical factors, radiation will finish you.

Artificial sources include:

• Nuclear weapon;
• Medical equipment;
• Waste from enterprises;
• Certain gems;
• Some vintage items removed from hazardous areas. Including from Chernobyl.

The norm of radioactive radiation

Scientists were able to establish that radiation affects individual organs and the whole organism in different ways. In order to assess the damage arising from chronic exposure, the concept of equivalent dose was introduced. It is calculated according to the formula and is equal to the product of the received dose, absorbed by the body and averaged over a specific organ or the entire human body, by a weight factor.

The unit of equivalent dose is the ratio of joules to kilograms, which is called sievert (Sv). With its use, a scale was created that allows you to understand the specific danger of radiation for humanity:

• 100 Sound Instant death. The victim has a few hours, a maximum of a couple of days.
• From 10 to 50 Sv. Those who have received injuries of this nature will die in a few weeks from severe internal bleeding.
• 4-5 Sound When this amount is ingested, the body copes in 50% of cases. Otherwise, the sad consequences lead to death after a couple of months due to damage to the bone marrow and circulatory disorders.
• 1 Sound With the absorption of such a dose, radiation sickness is inevitable.
• 0.75 Sound Changes in the circulatory system for a short period of time.
• 0.5 Sv. This amount is enough for the patient to develop cancer. The rest of the symptoms are absent.
• 0.3 Sv. This value is inherent in the apparatus for conducting x-rays of the stomach.
• 0.2 Sv. Permissible level for work with radioactive materials.
• 0.1 Sv. With this amount, uranium is mined.
• 0.05 Sound This value is the norm for irradiation of medical devices.
• 0.0005 Sv. Permissible amount of radiation level near the nuclear power plant. Also, this is the value of the annual exposure of the population, which is equated to the norm.

The safe dose of radiation for humans includes values ​​up to 0.0003-0.0005 Sv per hour. The maximum permissible exposure is 0.01 Sv per hour, if such exposure is short-lived.

The effect of radiation on humans

Radioactivity has a huge impact on the population. harmful effects not only people who are faced with danger are exposed, but also the next generation. Such circumstances are caused by the action of radiation on genetic level. There are two types of influence:

• Somatic. Diseases occur in a victim who has received a dose of radiation. Leads to the appearance of radiation sickness, leukemia, tumors of various organs, local radiation injuries.
• Genetic. Associated with a defect in the genetic apparatus. Shows up in later generations. Children, grandchildren and more distant descendants suffer. Gene mutations and chromosomal changes occur

In addition to the negative impact, there is also a favorable moment. Thanks to the study of radiation, scientists have managed to create on its basis a medical examination that can save lives.

Mutation after radiation

Consequences of irradiation

Upon receipt of chronic irradiation, recovery measures take place in the body. This leads to the fact that the victim acquires a lower load than he would receive with a single penetration of the same amount of radiation. Radionuclides are distributed unevenly inside a person. Most often affected: the respiratory system, digestive organs, liver, thyroid gland.

The enemy does not sleep even 4-10 years after exposure. Blood cancer can develop inside a person. It is especially dangerous for teenagers under the age of 15. It has been observed that the mortality of people working with x-ray equipment is increased due to leukemia.

The most frequent result of irradiation is radiation sickness, which occurs both with a single dose and with a long one. With a large number of radionuclides leads to death. Breast and thyroid cancer is common.

A huge number of organs suffer. vision is impaired and mental condition victim. Lung cancer is common among uranium miners. External irradiation causes terrible burns of the skin and mucous membranes.

Mutations

After exposure to radionuclides, two types of mutations are possible: dominant and recessive. The first occurs immediately after irradiation. The second type is found after a long period of time not in the victim, but in his next generation. Violations caused by mutation lead to deviations in the development of internal organs in the fetus, external deformities and changes in the psyche.

Unfortunately, mutations are poorly understood, as they usually do not appear immediately. After a while, it is difficult to understand what exactly had a dominant influence on its occurrence.