Ionizing radiation refers to those types of radiant energy that, when entering or penetrating certain environments, produce ionization in them. Radioactive radiation, high-energy radiation, X-rays, etc. have these properties.
The widespread use of atomic energy for peaceful purposes, various accelerator installations and X-ray machines for various purposes has determined the prevalence of ionizing radiation in the national economy and the huge, ever-increasing contingents of people working in this area.
Types of ionizing radiation and their properties
The most diverse types of ionizing radiation are the so-called radioactive radiation, which is formed as a result of the spontaneous radioactive decay of atomic nuclei of elements with a change in the physical and chemical properties of the latter. Elements that have the ability to decay radioactively are called radioactive; they can be natural, such as uranium, radium, thorium, etc. (about 50 elements in total), and artificial, for which the radioactive properties are obtained artificially (more than 700 elements).
During radioactive decay, there are three main types of ionizing radiation: alpha, beta and gamma.
An alpha particle is a positively charged helium ion formed during the decay of nuclei, usually of heavy natural elements (radium, thorium, etc.). These rays do not penetrate deeply into solid or liquid media, so to protect against external influences, it is enough to protect yourself with any thin layer, even a piece of paper.
Beta radiation is a stream of electrons produced by the decay of the nuclei of both natural and artificial radioactive elements. Beta radiation has greater penetrating power compared to alpha rays, which is why denser and thicker screens are required to protect against them. A type of beta radiation produced during the decay of some artificial radioactive elements are. positrons. They differ from electrons only in their positive charge, so when the beam of rays is exposed to a magnetic field, they are deflected in the opposite direction.
Gamma radiation, or energy quanta (photons), are hard electromagnetic vibrations produced during the decay of the nuclei of many radioactive elements. These rays have much greater penetrating power. Therefore, to shield from them, special devices are needed from materials that can block these rays well (lead, concrete, water). The ionizing effect of gamma radiation is mainly due to both the direct consumption of its own energy and the ionizing effect of electrons knocked out of the irradiated substance.
X-ray radiation is generated during the operation of X-ray tubes, as well as complex electronic installations (betatrons, etc.). X-rays are similar in nature to gamma rays, but differ in origin and sometimes wavelength: X-rays generally have longer wavelengths and lower frequencies than gamma rays. Ionization due to exposure to X-rays occurs largely due to the electrons they knock out and only slightly due to the direct waste of their own energy. These rays (especially hard ones) also have significant penetrating power.
Neutron radiation is a stream of neutral, that is, uncharged particles of neutrons (n) that are an integral part of all nuclei, with the exception of the hydrogen atom. They do not have charges, so they themselves do not have an ionizing effect, but a very significant ionizing effect occurs due to the interaction of neutrons with the nuclei of irradiated substances. Substances irradiated by neutrons can acquire radioactive properties, that is, receive so-called induced radioactivity. Neutron radiation is generated during the operation of particle accelerators, nuclear reactors, etc. Neutron radiation has the greatest penetrating power. Neutrons are retained by substances containing hydrogen in their molecules (water, paraffin, etc.).
All types of ionizing radiation differ from each other by different charges, mass and energy. There are also differences within each type of ionizing radiation, causing greater or lesser penetrating and ionizing ability and their other features. The intensity of all types of radioactive radiation, as with other types of radiant energy, is inversely proportional to the square of the distance from the radiation source, that is, when the distance doubles or triples, the intensity of radiation decreases by 4 and 9 times, respectively.
Radioactive elements can be present in the form of solids, liquids and gases, therefore, in addition to their specific property of radiation, they have the corresponding properties of these three states; they can form aerosols, vapors, spread in the air, contaminate surrounding surfaces, including equipment, workwear, workers’ skin, etc., and penetrate the digestive tract and respiratory organs.
Ionizing radiation is any radiation that causes ionization of a medium, i.e. the flow of electrical currents in this environment, including in the human body, which often leads to cell destruction, changes in blood composition, burns and other serious consequences.
Sources of ionizing radiation are radioactive elements and their isotopes, nuclear reactors, charged particle accelerators, etc. X-ray installations and high-voltage direct current sources are sources of X-ray radiation.
It should be noted here that during normal operation, the radiation hazard is insignificant. It occurs when an emergency occurs and can manifest itself for a long time in the event of radioactive contamination of the area.
Ionizing radiation is divided into two types: electromagnetic (gamma radiation and X-rays) and corpuscular, which is - and -particles, neutrons, etc.
Exposure to ionizing radiation.
Any type of ionizing radiation causes biological changes in the body, both during external (the source is outside the body) and internal irradiation (radioactive substances, i.e. particles, enter the body with food, through the respiratory system).
A single exposure to radiation causes biological damage that depends on the total absorbed dose. So, at a dose of up to 0.25 Gy, there are no visible violations, but already at 4 - 5 Gy, deaths account for 50% of the total number of victims, and at 6 Gy or more - 100% of victims. (Gr - gray).
The main mechanism of action is associated with the processes of ionization of atoms and molecules of living matter, in particular water molecules contained in cells. It is they who are subject to intense destruction. The changes caused can be reversible or irreversible and occur in the chronic form of radiation sickness.
-radiation, which travels at the speed of light, has great penetrating power; it can only be stopped by a thick lead or concrete slab.
Sources of external exposure.
The radioactive background created by cosmic rays (0.3 mSv/year) provides slightly less than half of the total external radiation (0.65 mSv/year) received by the population. There is no place on Earth where cosmic rays cannot penetrate. It should be noted that the North and South Poles receive more radiation than the equatorial regions. This happens due to the presence of a magnetic field near the Earth, the lines of force of which enter and exit at the poles.
However, a more significant role is played by the location of the person. The higher it rises above sea level, the stronger the irradiation becomes, because the thickness of the air layer and its density decrease as it rises, and consequently, the protective properties decrease.
Earthly radiation, which provides approximately 0.35 mSv/year of external exposure, comes mainly from those mineral rocks that contain potassium - 40, rubidium - 87, uranium - 238, thorium - 232.
Naturally, the levels of terrestrial radiation on our planet are not the same and mostly range from 0.3 to 0.6 mSv/year. There are places where these figures are many times higher.
Internal exposure of the population.
Two-thirds of internal exposure of the population from natural sources comes from the ingestion of radioactive substances into the body through food, water and air.
On average, a person receives about 180 μSv/year due to potassium - 40, which is absorbed by the body along with non-radioactive potassium, necessary for life. Nuclides lead - 210, polonium - 210 are concentrated in fish and shellfish. Therefore, people who consume a lot of fish and other seafood receive relatively high doses of internal radiation.
Residents of northern regions who eat deer meat are also exposed to higher levels of radiation, because the lichen that deer eat in winter concentrates significant amounts of radioactive isotopes of polonium and lead.
Radon is released from the earth's crust everywhere, so a person receives the maximum amount of exposure from it while in a closed, unventilated room on the lower floors of buildings, where the gas seeps through the foundation and floor. Its concentration in enclosed spaces is usually 8 times higher than on the street, and on the upper floors it is lower than on the ground floor.
Wood, brick, and concrete emit a small amount of gas, but granite and iron emit much more. Alumina is very radioactive. Some industrial wastes used in construction have relatively high radioactivity, for example, red clay bricks (aluminum production waste), blast furnace slag (in ferrous metallurgy), fly ash (formed by burning coal).
Other sources of radon in residential areas include water and natural gas. We must remember that there is much more of it in raw water, and when boiled, radon evaporates, so the main danger is its entry into the lungs with water vapor. Most often this happens in the bathroom when taking a hot shower.
Radon poses exactly the same danger when it mixes underground with natural gas, which, when burned in cookers, heating and other heating devices, enters the room. Its concentration increases greatly in the absence of good exhaust systems.
We also must not forget that when coal is burned, a significant part of its components is sintered into slag or ash, where radioactive substances are concentrated.
The lighter part of them - fly ash - is carried into the air, which also leads to additional exposure of people.
From stoves and fireplaces around the world, no less fly ash flies into the atmosphere than from the chimneys of a power plant.
Medical procedures and treatments involving the use of radioactivity are the main contributors to the dose received by humans from man-made sources.
Thus, with dental x-rays, a person receives a local one-time exposure of 0.03 Sv (3 rem), with stomach x-rays - 0.3 Sv (30 rem), with fluorography - 3.7 mSv (370 mrem).
Nuclear explosions also contribute to an increase in human radiation dose. Radioactive fallout from testing in the atmosphere spreads throughout the planet, increasing the overall level of pollution.
Another source of radioactive contamination are mines and enrichment plants. During the processing of uranium ore, a huge amount of waste is generated - “tails”, which remain radioactive for millions of years. They are the main long-lived source of exposure to the population. To summarize, it must be said that average radiation doses from nuclear energy are very small compared to doses received from natural sources (more than 1%).
In industry and at home, due to the use of various technical means, people also receive additional, albeit small, radiation. For example, workers who are involved in the production of phosphors using radioactive materials, at construction factories and industrial sites where industrial flaw detection installations are used.
Miners, miners, gold miners, and personnel at resorts with radon sources receive increased doses underground.
The most common household irradiator is a watch with a luminous dial.
They give an annual dose 4 times higher than that caused by a leak at a nuclear power plant. At a distance of 1 meter from the dial, the radiation is usually 10,000 times weaker than at 1 centimeter.
The source of X-ray radiation is a color TV. When watching, for example, one hockey match, a person receives radiation exposure of 0.1 μSv (1 μrem). If you watch programs every day for 3 hours for a year, the radiation dose will be 5 μSv.
Thus, in modern conditions, in the presence of a high natural radiation background, with existing technological processes, every inhabitant of the Earth annually receives a radiation dose of
on average 2 – 3 mSv (200 – 300 mrem).
Article navigation:
In the process of decay of a substance or its synthesis, the elements of an atom (protons, neutrons, electrons, photons) are released, otherwise we can say radiation occurs these elements. Such radiation is called - ionizing radiation or what is more common radioactive radiation, or even simpler radiation . Ionizing radiation also includes x-rays and gamma radiation.
Radiation is the process of emission of charged elementary particles by matter, in the form of electrons, protons, neutrons, helium atoms or photons and muons. The type of radiation depends on which element is emitted.
Ionization is the process of formation of positively or negatively charged ions or free electrons from neutrally charged atoms or molecules.
Radioactive (ionizing) radiation can be divided into several types, depending on the type of elements from which it consists. Different types of radiation are caused by different microparticles and therefore have different energetic effects on matter, different abilities to penetrate through it and, as a result, different biological effects of radiation.
Alpha, beta and neutron radiation- These are radiations consisting of various particles of atoms.
Gamma and X-rays is the emission of energy.
Alpha radiation
- emitted: two protons and two neutrons
- penetrating ability: low
- irradiation from source: up to 10 cm
- emission speed: 20,000 km/s
- ionization: 30,000 ion pairs per 1 cm of travel
- high
Alpha (α) radiation occurs during the decay of unstable isotopes elements.
Alpha radiation- this is the radiation of heavy, positively charged alpha particles, which are the nuclei of helium atoms (two neutrons and two protons). Alpha particles are emitted during the decay of more complex nuclei, for example, during the decay of atoms of uranium, radium, and thorium.
Alpha particles have a large mass and are emitted at a relatively low speed of an average of 20 thousand km/s, which is approximately 15 times less than the speed of light. Since alpha particles are very heavy, upon contact with a substance, the particles collide with the molecules of this substance, begin to interact with them, losing their energy, and therefore the penetrating ability of these particles is not great and even a simple sheet of paper can hold them back.
However, alpha particles carry a lot of energy and, when interacting with matter, cause significant ionization. And in the cells of a living organism, in addition to ionization, alpha radiation destroys tissue, leading to various damage to living cells.
Of all types of radiation, alpha radiation has the least penetrating power, but the consequences of irradiation of living tissues with this type of radiation are the most severe and significant compared to other types of radiation.
Exposure to alpha radiation can occur when radioactive elements enter the body, for example through air, water or food, or through cuts or wounds. Once in the body, these radioactive elements are carried through the bloodstream throughout the body, accumulate in tissues and organs, exerting a powerful energetic effect on them. Since some types of radioactive isotopes emitting alpha radiation have a long lifespan, when they enter the body, they can cause serious changes in cells and lead to tissue degeneration and mutations.
Radioactive isotopes are actually not eliminated from the body on their own, so once they get inside the body, they will irradiate the tissues from the inside for many years until they lead to serious changes. The human body is not able to neutralize, process, assimilate or utilize most radioactive isotopes that enter the body.
Neutron radiation
- emitted: neutrons
- penetrating ability: high
- irradiation from source: kilometers
- emission speed: 40,000 km/s
- ionization: from 3000 to 5000 ion pairs per 1 cm of run
- biological effects of radiation: high
Neutron radiation- this is man-made radiation arising in various nuclear reactors and during atomic explosions. Also, neutron radiation is emitted by stars in which active thermonuclear reactions occur.
Having no charge, neutron radiation colliding with matter weakly interacts with the elements of atoms at the atomic level, and therefore has high penetrating power. You can stop neutron radiation using materials with a high hydrogen content, for example, a container of water. Also, neutron radiation does not penetrate polyethylene well.
Neutron radiation, when passing through biological tissues, causes serious damage to cells, since it has a significant mass and a higher speed than alpha radiation.
Beta radiation
- emitted: electrons or positrons
- penetrating ability: average
- irradiation from source: up to 20 m
- emission speed: 300,000 km/s
- ionization: from 40 to 150 ion pairs per 1 cm of travel
- biological effects of radiation: average
Beta (β) radiation occurs when one element transforms into another, while the processes occur in the very nucleus of the atom of the substance with a change in the properties of protons and neutrons.
With beta radiation, a neutron is transformed into a proton or a proton into a neutron; during this transformation, an electron or positron (electron antiparticle) is emitted, depending on the type of transformation. The speed of the emitted elements approaches the speed of light and is approximately equal to 300,000 km/s. The elements emitted during this process are called beta particles.
Having an initially high radiation speed and small sizes of emitted elements, beta radiation has a higher penetrating ability than alpha radiation, but has hundreds of times less ability to ionize matter compared to alpha radiation.
Beta radiation easily penetrates clothing and partially through living tissue, but when passing through denser structures of matter, for example, through metal, it begins to interact with it more intensely and loses most of its energy, transferring it to the elements of the substance. A metal sheet of a few millimeters can completely stop beta radiation.
If alpha radiation poses a danger only in direct contact with a radioactive isotope, then beta radiation, depending on its intensity, can already cause significant harm to a living organism at a distance of several tens of meters from the radiation source.
If a radioactive isotope emitting beta radiation enters a living organism, it accumulates in tissues and organs, exerting an energetic effect on them, leading to changes in the structure of the tissue and, over time, causing significant damage.
Some radioactive isotopes with beta radiation have a long decay period, that is, once they enter the body, they will irradiate it for years until they lead to tissue degeneration and, as a consequence, cancer.
Gamma radiation
- emitted: energy in the form of photons
- penetrating ability: high
- irradiation from source: up to hundreds of meters
- emission speed: 300,000 km/s
- ionization:
- biological effects of radiation: low
Gamma (γ) radiation is energetic electromagnetic radiation in the form of photons.
Gamma radiation accompanies the process of decay of atoms of matter and manifests itself in the form of emitted electromagnetic energy in the form of photons, released when the energy state of the atomic nucleus changes. Gamma rays are emitted from the nucleus at the speed of light.
When radioactive decay of an atom occurs, other substances are formed from one substance. The atom of newly formed substances is in an energetically unstable (excited) state. By influencing each other, neutrons and protons in the nucleus come to a state where the interaction forces are balanced, and excess energy is emitted by the atom in the form of gamma radiation
Gamma radiation has a high penetrating ability and easily penetrates clothing, living tissue, and a little more difficult through dense structures of substances such as metal. To stop gamma radiation, a significant thickness of steel or concrete will be required. But at the same time, gamma radiation has a hundred times weaker effect on matter than beta radiation and tens of thousands of times weaker than alpha radiation.
The main danger of gamma radiation is its ability to travel significant distances and affect living organisms several hundred meters from the source of gamma radiation.
X-ray radiation
- emitted: energy in the form of photons
- penetrating ability: high
- irradiation from source: up to hundreds of meters
- emission speed: 300,000 km/s
- ionization: from 3 to 5 pairs of ions per 1 cm of travel
- biological effects of radiation: low
X-ray radiation- this is energetic electromagnetic radiation in the form of photons that arise when an electron inside an atom moves from one orbit to another.
X-ray radiation is similar in effect to gamma radiation, but has less penetrating power because it has a longer wavelength.
Having examined the various types of radioactive radiation, it is clear that the concept of radiation includes completely different types of radiation that have different effects on matter and living tissues, from direct bombardment with elementary particles (alpha, beta and neutron radiation) to energy effects in the form of gamma and x-rays cure.
Each of the radiations discussed is dangerous!
Comparative table with characteristics of different types of radiation
| characteristic | Type of radiation | ||||
| Alpha radiation | Neutron radiation | Beta radiation | Gamma radiation | X-ray radiation | |
| are emitted | two protons and two neutrons | neutrons | electrons or positrons | energy in the form of photons | energy in the form of photons |
| penetrating power | low | high | average | high | high |
| exposure from source | up to 10 cm | kilometers | up to 20 m | hundreds of meters | hundreds of meters |
| radiation speed | 20,000 km/s | 40,000 km/s | 300,000 km/s | 300,000 km/s | 300,000 km/s |
| ionization, steam per 1 cm of travel | 30 000 | from 3000 to 5000 | from 40 to 150 | from 3 to 5 | from 3 to 5 |
| biological effects of radiation | high | high | average | low | low |
As can be seen from the table, depending on the type of radiation, radiation at the same intensity, for example 0.1 Roentgen, will have a different destructive effect on the cells of a living organism. To take this difference into account, a coefficient k was introduced, reflecting the degree of exposure to radioactive radiation on living objects.
| Factor k | |
| Type of radiation and energy range | Weight multiplier |
| Photons all energies (gamma radiation) | 1 |
| Electrons and muons all energies (beta radiation) | 1 |
| Neutrons with energy < 10 КэВ (нейтронное излучение) | 5 |
| Neutrons from 10 to 100 KeV (neutron radiation) | 10 |
| Neutrons from 100 KeV to 2 MeV (neutron radiation) | 20 |
| Neutrons from 2 MeV to 20 MeV (neutron radiation) | 10 |
| Neutrons> 20 MeV (neutron radiation) | 5 |
| Protons with energies > 2 MeV (except for recoil protons) | 5 |
| Alpha particles, fission fragments and other heavy nuclei (alpha radiation) | 20 |
The higher the “k coefficient,” the more dangerous the effect of a certain type of radiation is on the tissues of a living organism.
Video:
- Ionizing radiation is a type of energy released by atoms in the form of electromagnetic waves or particles.
- Humans are exposed to natural sources of ionizing radiation such as soil, water, plants, and to man-made sources such as X-rays and medical devices.
- Ionizing radiation has numerous beneficial uses, including in medicine, industry, agriculture and scientific research.
- As the use of ionizing radiation increases, so does the potential for health hazards if it is used or limited inappropriately.
- Acute health effects, such as skin burn or acute radiation syndrome, can occur when the radiation dose exceeds certain levels.
- Low doses of ionizing radiation can increase the risk of longer-term effects such as cancer.
What is ionizing radiation?
Ionizing radiation is a type of energy released by atoms in the form of electromagnetic waves (gamma or x-rays) or particles (neutrons, beta or alpha). The spontaneous decay of atoms is called radioactivity, and the excess energy resulting is a form of ionizing radiation. Unstable elements that form during decay and emit ionizing radiation are called radionuclides.
All radionuclides are uniquely identified by the type of radiation they emit, the energy of the radiation, and their half-life.
Activity, used as a measure of the amount of radionuclide present, is expressed in units called becquerels (Bq): one becquerel is one decay event per second. Half-life is the time required for the activity of a radionuclide to decay to half its original value. The half-life of a radioactive element is the time during which half of its atoms decay. It can range from fractions of a second to millions of years (for example, the half-life of iodine-131 is 8 days, and the half-life of carbon-14 is 5730 years).
Radiation sources
People are exposed to natural and artificial radiation every day. Natural radiation comes from numerous sources, including more than 60 naturally occurring radioactive substances in soil, water and air. Radon, a naturally occurring gas, is formed from rocks and soil and is a major source of natural radiation. Every day, people inhale and absorb radionuclides from the air, food and water.
People are also exposed to natural radiation from cosmic rays, especially at high altitudes. On average, 80% of the annual dose that a person receives from background radiation comes from naturally occurring terrestrial and space radiation sources. Levels of such radiation vary across geographies, and in some areas levels can be 200 times higher than the global average.
Humans are also exposed to radiation from man-made sources, from nuclear energy production to the medical use of radiation diagnostics or treatment. Today, the most common artificial sources of ionizing radiation are medical machines, such as X-ray machines and other medical devices.
Exposure to ionizing radiation
Exposure to radiation can be internal or external and can occur in a variety of ways.
Internal impact Ionizing radiation occurs when radionuclides are inhaled, ingested, or otherwise enter the circulation (eg, by injection, injury). Internal exposure ceases when the radionuclide is eliminated from the body either spontaneously (in excrement) or as a result of treatment.
External radioactive contamination can occur when radioactive material in the air (dust, liquid, aerosols) settles on skin or clothing. Such radioactive material can often be removed from the body by simple washing.
Exposure to ionizing radiation may also occur as a result of external radiation from a relevant external source (for example, such as exposure to radiation emitted by medical x-ray equipment). External exposure stops when the radiation source is closed or when the person moves outside the radiation field.
People may be exposed to ionizing radiation in a variety of settings: at home or in public places (public exposure), in their workplaces (occupational exposure) or in health care settings (patients, carers and volunteers).
Exposure to ionizing radiation can be classified into three types of exposure.
The first is planned exposure, which results from the intentional use and operation of radiation sources for specific purposes, such as the medical use of radiation to diagnose or treat patients, or the use of radiation in industry or scientific research.
The second case is existing sources of exposure, where radiation exposure already exists and for which appropriate control measures must be taken, for example, exposure to radon in homes or workplaces or exposure to background natural radiation in environmental conditions.
The latter is exposure to emergencies caused by unexpected events requiring prompt action, such as nuclear incidents or malicious acts.
Medical uses of radiation account for 98% of the total radiation dose from all artificial sources; it represents 20% of the total impact on the population. Every year, 3,600 million radiological examinations for diagnostic purposes, 37 million procedures using nuclear materials and 7.5 million radiotherapy procedures for curative purposes are performed worldwide.
Health effects of ionizing radiation
Radiation damage to tissues and/or organs depends on the radiation dose received or the absorbed dose, which is expressed in grays (Gy).
Effective dose is used to measure ionizing radiation in terms of its potential to cause harm. Sievert (Sv) is a unit of effective dose that takes into account the type of radiation and the sensitivity of tissue and organs. It makes it possible to measure ionizing radiation in terms of its potential to cause harm. Sv takes into account the type of radiation and the sensitivity of organs and tissues.
Sv is a very large unit, so it is more practical to use smaller units such as millisievert (mSv) or microsievert (µSv). One mSv contains one thousand µSv, and one thousand mSv equals one Sv. In addition to the amount of radiation (dose), it is often useful to show the rate of release of that dose, for example µSv/hour or mSv/year.
Above certain thresholds, radiation may impair the functioning of tissues and/or organs and may cause acute reactions such as reddening of the skin, hair loss, radiation burns, or acute radiation syndrome. These reactions are more severe at higher doses and at higher dose rates. For example, the threshold dose for acute radiation syndrome is approximately 1 Sv (1000 mSv).
If the dose is low and/or applied over a long period of time (low dose rate), the associated risk is significantly reduced because the likelihood of tissue repair increases. However, there is a risk of long-term consequences, such as cancer, which can take years or even decades to appear. Effects of this type do not always occur, but their likelihood is proportional to the radiation dose. This risk is higher in the case of children and adolescents, as they are much more sensitive to the effects of radiation than adults.
Epidemiological studies in exposed populations, such as atomic bomb survivors or radiotherapy patients, have shown a significant increase in the likelihood of cancer at doses above 100 mSv. In some cases, more recent epidemiological studies in people who were medically exposed as children (childhood CT) suggest that the likelihood of cancer may be increased even at lower doses (in the 50-100 mSv range) .
Prenatal exposure to ionizing radiation can cause fetal brain damage at high doses exceeding 100 mSv between 8 and 15 weeks of pregnancy and 200 mSv between 16 and 25 weeks of pregnancy. Studies in humans have shown that there is no radiation-related risk to fetal brain development before week 8 or after week 25 of pregnancy. Epidemiological studies suggest that the risk of fetal cancer after exposure to radiation is similar to the risk after early childhood exposure.
WHO activities
WHO has developed a radiation program to protect patients, workers and the public from the health hazards of radiation in planned, existing and emergency exposure events. This program, which focuses on public health aspects, covers activities related to radiation risk assessment, management and communication.
In line with its core function of “establishing norms and standards, promoting compliance and monitoring them accordingly”, WHO collaborates with 7 other international organizations to review and update international standards for basic radiation safety (BRS). WHO adopted new international PRSs in 2012 and is currently working to support the implementation of PRSs in its Member States.
Atomic energy is quite actively used for peaceful purposes, for example, in the operation of an X-ray machine and an accelerator installation, which made it possible to distribute ionizing radiation in the national economy. Considering that a person is exposed to it every day, it is necessary to find out what the consequences of dangerous contact can be and how to protect yourself.
Main characteristics
Ionizing radiation is a type of radiant energy that enters a specific environment, causing the process of ionization in the body. This characteristic of ionizing radiation is suitable for X-rays, radioactive and high energies, and much more.
Ionizing radiation has a direct effect on the human body. Despite the fact that ionizing radiation can be used in medicine, it is extremely dangerous, as evidenced by its characteristics and properties.
Well-known varieties are radioactive irradiations, which appear due to the arbitrary splitting of the atomic nucleus, which causes a transformation of chemical and physical properties. Substances that can decay are considered radioactive.
They can be artificial (seven hundred elements), natural (fifty elements) - thorium, uranium, radium. It should be noted that they have carcinogenic properties; toxins are released as a result of exposure to humans and can cause cancer and radiation sickness.
It is necessary to note the following types of ionizing radiation that affect the human body:
Alpha
They are considered positively charged helium ions, which appear in the event of the decay of the nuclei of heavy elements. Protection against ionizing radiation is carried out using a piece of paper or cloth.
Beta
– a flow of negatively charged electrons that appear in the event of the decay of radioactive elements: artificial, natural. The damaging factor is much higher than that of the previous species. As protection you will need a thick screen, more durable. Such radiations include positrons.
Gamma
- a hard electromagnetic oscillation that appears after the decay of nuclei of radioactive substances. A high penetrating factor is observed and is the most dangerous radiation of the three listed for the human body. To shield the rays, you need to use special devices. For this you will need good and durable materials: water, lead and concrete.
X-ray
Ionizing radiation is generated in the process of working with a tube and complex installations. The characteristic resembles gamma rays. The difference lies in the origin and wavelength. There is a penetrating factor.
Neutron
Neutron radiation is a stream of uncharged neutrons that are part of nuclei, except hydrogen. As a result of irradiation, substances receive a portion of radioactivity. There is the largest penetrating factor. All these types of ionizing radiation are very dangerous.
Main sources of radiation
Sources of ionizing radiation can be artificial or natural. Basically, the human body receives radiation from natural sources, these include:
- terrestrial radiation;
- internal irradiation.
As for the sources of terrestrial radiation, many of them are carcinogenic. These include:
- Uranus;
- potassium;
- thorium;
- polonium;
- lead;
- rubidium;
- radon.
The danger is that they are carcinogenic. Radon is a gas that has no odor, color, or taste. It is seven and a half times heavier than air. Its decay products are much more dangerous than gas, so the impact on the human body is extremely tragic.
Artificial sources include:
- nuclear energy;
- enrichment factories;
- uranium mines;
- burial grounds with radioactive waste;
- X-ray machines;
- nuclear explosion;
- scientific laboratories;
- radionuclides, which are actively used in modern medicine;
- lighting devices;
- computers and phones;
- Appliances.
If these sources are nearby, there is a factor of the absorbed dose of ionizing radiation, the unit of which depends on the duration of exposure to the human body.
The operation of sources of ionizing radiation occurs every day, for example: when you work at a computer, watch a TV show or talk on a mobile phone or smartphone. All of these sources are to some extent carcinogenic and can cause severe and fatal diseases.
The placement of sources of ionizing radiation includes a list of important, responsible work related to the development of a project for the location of irradiation installations. All radiation sources contain a specific unit of radiation, each of which has a specific effect on the human body. This includes manipulations carried out for installation and commissioning of these installations.
It should be noted that disposal of sources of ionizing radiation is mandatory.
This is a process that helps decommission generation sources. This procedure consists of technical and administrative measures that are aimed at ensuring the safety of personnel, the population, and there is also an environmental protection factor. Carcinogenic sources and equipment are a huge danger to the human body, so they must be disposed of.
Features of radiation registration
The characteristics of ionizing radiation show that they are invisible, odorless and colorless, so they are difficult to notice.
For this purpose, there are methods for recording ionizing radiation. As for the methods of detection and measurement, everything is done indirectly, using some property as a basis.
The following methods for detecting ionizing radiation are used:
- Physical: ionization, proportional counter, gas-discharge Geiger-Muller counter, ionization chamber, semiconductor counter.
- Calorimetric detection method: biological, clinical, photographic, hematological, cytogenetic.
- Luminescent: fluorescent and scintillation counters.
- Biophysical method: radiometry, calculation.
Dosimetry of ionizing radiation is carried out using instruments; they are able to determine the radiation dose. The device includes three main parts - a pulse counter, a sensor, and a power source. Radiation dosimetry is possible thanks to a dosimeter or radiometer.
Effects on humans
The effect of ionizing radiation on the human body is especially dangerous. The following consequences are possible:
- there is a factor of very profound biological change;
- there is a cumulative effect of a unit of absorbed radiation;
- the effect manifests itself over time, as there is a latent period;
- all internal organs and systems have different sensitivity to a unit of absorbed radiation;
- radiation affects all offspring;
- the effect depends on the unit of radiation absorbed, the radiation dose, and duration.
Despite the use of radiation devices in medicine, their effects can be harmful. The biological effect of ionizing radiation in the process of uniform irradiation of the body, calculated at 100% of the dose, occurs as follows:
- bone marrow – unit of absorbed radiation 12%;
- lungs – at least 12%;
- bones – 3%;
- testes, ovaries– absorbed dose of ionizing radiation about 25%;
- thyroid gland– absorbed dose unit about 3%;
- mammary glands – approximately 15%;
- other tissues - the unit of absorbed radiation dose is 30%.
As a result, various diseases can occur, including oncology, paralysis and radiation sickness. It is extremely dangerous for children and pregnant women, as abnormal development of organs and tissues occurs. Toxins and radiation are sources of dangerous diseases.
