As you know, there are several types of ionizing radiation with different effects on the body and penetrating ability:
- alpha radiation - a stream of heavy positively charged particles (nuclei of helium atoms). The range of alpha particles in a substance is hundredths of a millimeter in the body or a few centimeters in the air. A regular sheet of paper can hold these particles. However, when such substances enter the body with food, water or air, they are carried throughout the body and concentrated in the internal organs, thus causing internal irradiation of the body. The danger of getting a source of alpha particles into the body is extremely high, since they cause maximum damage to cells due to their large mass;
- beta radiation is a stream of electrons or positrons emitted during radioactive beta decay of the nuclei of certain atoms. Electrons are much smaller than alpha particles and can penetrate deep into the body by 10-15 centimeters, which can be dangerous when directly interacting with a radiation source, and it is also dangerous to get a radiation source, for example, in the form of dust, into the body. For protection against beta radiation, an organic glass screen can be used;
- neutron radiation is a neutron flux. Neutrons do not have a direct ionizing effect, however, a significant ionizing effect occurs due to elastic and inelastic scattering on the nuclei of a substance. Also, neutron-irradiated substances can acquire radioactive properties, that is, acquire induced radioactivity. Neutron radiation has the highest penetrating power;
- gamma radiation and x-ray radiation refer to electromagnetic radiation differing in wavelength. Gamma radiation with a small wavelength, which occurs during the decay of radioactive nuclei, has the highest penetrating power. To attenuate the gamma radiation flux, substances with a high density are used: lead, tungsten, uranium, concrete with metal fillers.
Radiation in the home
In the XX century, radioactive substances began to be widely used in energy, medicine and industry. The attitude to radiation at that time was rather frivolous - the potential danger of radioactive radiation was underestimated, and sometimes not taken at all, into account, it is enough to recall the appearance of clocks and Christmas decorations with radioactive illumination:
The first luminous paint based on radium salts was made in 1902, then it began to be used for a large number of applied tasks, even painted Christmas toys and children's books for the sake of radiance. Wrist watches with numbers filled with radioactive paint became the standard for the military, all watches during the First World War were with radium paint on numbers and hands. Large chronometers with a large dial and numbers could sound up to 10 000 micro-roentgen per hour (pay attention to this figure, we will return to it later).
The well-known uranium was used as part of colored glaze to cover dishes and porcelain figures. The power of the equivalent dose of household items decorated in this way can reach 15 microsievert per hour, or 1500 micro-roentgen per hour (I also suggest remembering this figure).
Radioactive household items
One can only assume how many workers and consumers died or became disabled in the manufacturing process of the above products.
However, for the most part, ordinary citizens have rarely encountered radioactivity. The incidents that occurred on ships and submarines, as well as on closed enterprises, were classified, information about them was not accessible to the general public. On the supply of military and civilian specialists there were specialized devices - dosimeters. Under the generic name "dosimeter", there is a hidden range of devices for various purposes intended for signaling and measuring radiation power (dosimeters-meters), search for radiation sources (search engines) or determine the type of emitter (spectrometers), however, for most citizens, the very concept of "dosimeter" "At that time did not exist.
The disaster at the Chernobyl nuclear power plant and the appearance of household dosimeters in the USSR
Everything changed on 26 on April 1986, when the largest technological disaster occurred - the accident at the Chernobyl nuclear power plant (NPP). The scale of the disaster was such that it was not possible to classify them. From this moment the word "radiation" has become one of the most used in the Russian language.
The destroyed fourth power unit of the Chernobyl nuclear power plant
About three years after the accident, the National Commission on Radiation Protection developed a “Concept for a radiation monitoring system for public use”, which recommended the production of simple small-sized household dosimeters-meters for use by the public, especially in those areas that were exposed to radiation infection.
The result of this decision was the explosive expansion of dosimeter production in the Soviet Union.
The first Soviet household dosimeters IR-01 "Bella", ANRI-01 "Pine", DBG-06T, "Raton-901"
Perhaps the best dosimeter for its time, the RKS-20.03 Pripyat dosimeter
Features of the sensors used in household dosimeters of that time made it possible to determine only gamma radiation, and in some cases, hard beta radiation. This made it possible to determine the infected area, but to solve such a problem as determining the radioactivity of products, household dosimeters of that time were useless. It can be said that because of the accident at the Chernobyl nuclear power plant, the USSR, and then the CIS countries - Russia, Belarus, Ukraine, for a long time they became leaders in the production of dosimeters for various purposes.
The SBM-20 Geiger-Muller counters used in dosimeters and the compact SBM-10, SBM-21 counters allow detecting gamma radiation and partially hard beta radiation, are not sensitive to alpha radiation and soft beta radiation
Over time, the fear of radiation began to fade. Dosimeters gradually went out of use, becoming the lot of specialists who use them as part of their labor activities, and “stalkers” - lovers of visiting abandoned industrial and military facilities. A certain educational function was made by computer games of the post-acalyptic type, in which the dosimeter was often an integral part of the equipment of the game character.
Interest in dosimeters returned after the accident at the Japanese Fukushima-1 nuclear power plant in March 2011 as a result of a strong earthquake and tsunami. Despite the smaller scale compared to the accident at the Chernobyl nuclear power plant, a significant territory was exposed to radioactive substances, and many radioactive substances fell into the ocean.
In Japan itself, dosimeters were swept away from store shelves. Due to the specifics of this product, the number of dosimeters in stores was extremely limited, which led to their shortage. In the first six months after the accident, thousands of dosimeters were delivered to Japan by Russian, Belarusian and Ukrainian manufacturers.
Due to the close proximity of Japan and the Far Eastern part of the Russian Federation, radiation panic has reached the inhabitants of our country. In stores, stocks of dosimeters were bought up; in pharmacies, stocks of alcoholic solution of iodine, absolutely useless in terms of counteracting radiation, were bought up. Of particular concern to the population was the possible entry into the Russian market of food products exposed to radioactive isotopes, and the appearance on the market of radioactive cars and spare parts for them.
By the time of the accident at the Fukushima-1 nuclear power plant, dosimeters had changed. Modern dosimeters-radiometers differ significantly in their capabilities from their predecessors of the Soviet development. As manufacturers, some manufacturers began to use Geiger - Muller end mica counters, sensitive not only to gamma, but also to soft beta radiation, and some models, using special operation algorithms, even detect alpha radiation. The ability to detect alpha radiation allows you to determine the surface contamination of products with radionuclides, and the ability to determine beta radiation allows you to detect dangerous household objects, the activity of which is mostly manifested in the form of beta radiation.
Signal processing time was reduced - dosimeters began to work faster, calculate the accumulated radiation dose, and the built-in non-volatile memory allows saving measurement results for a long period of use of the dosimeter.
Modern dosimeters-radiometers: Radeks MKS-1009, Radioscan-701A, MKS-01CA1
Geiger end mica counter - Muller Beta-1-1
In principle, professional equipment is also available to the public, equipped with several types of sensors capable of detecting all types of radiation, including neutron radiation. Some of these models are equipped with scintillation crystals, which allow high-speed search for radioactive materials, but the cost of such devices usually goes beyond all reasonable boundaries, which makes them accessible to a limited circle of specialists.
Search signaling indicator-ICP-PM1703MA and gamma and X-ray dosimeter DKG-09D Chizh
It should be noted that scintillation crystals detect only gamma radiation, that is, search dosimeters that use only scintillation crystals as a detector are unable to detect alpha and beta radiation.
As in the case of the accident at the Chernobyl nuclear power plant, over time, the hype from the Fukushima-1 nuclear power plant began to subside. The demand for radiometric equipment among the population sharply declined.
August 8, 2019 at the Nenoksa military training ground of the White Sea Naval Base of the North fleet in the waters of the Dvina Bay of the White Sea near the village of Sopka, an explosion occurred on the offshore platform, which killed five RFNC-VNIIEF employees, two military personnel died from injuries in a hospital and four more people received a high radiation dose and were hospitalized. In Severodvinsk, 30 km from this place, a short-term increase in the background radiation to 2 microsievert per hour (200 microroentgen per hour) was recorded at the usual level of 0,11 microsievert per hour (11 microroentgen per hour).
There is no reliable information about the incident. According to one information, radiation contamination arose due to damage to a radioisotope source during the explosion of a rocket engine, according to another, due to the explosion of a test sample of a Burevestnik cruise missile with a nuclear rocket engine.
The organization of a comprehensive nuclear test ban treaty has published a map of the possible spread of radionuclides after the explosion, but the reliability of the information displayed on it is unknown.
Map of the possible expansion of radionuclides after the explosion in Nenoks
The reaction of the population to news about a possible radioactive infection is similar to that after the accident at the Fukushima-1 nuclear power plant - the purchase of dosimeters and an alcoholic solution of iodine ...
Of course, the radiation incident in Nyonoks is not comparable with such major radiation disasters as the accident at the Chernobyl nuclear power plant or the Fukushima-1 nuclear power plant. Rather, it can serve as an indicator of the unpredictability of the occurrence of radiation-hazardous situations in Russia and in the world.
Dosimeters as a means of survival
How necessary is a household dosimeter in everyday life? Here you can express yourself unambiguously - most of the time it will lie on a shelf, this is not an item that in everyday life will be in demand daily. On the other hand, in the event of a radiation accident or accident, it will be practically impossible to purchase a dosimeter, since their number in stores is limited. As the experience of the accident at the Fukushima-1 NPP showed, the market will be saturated about six months after the accident. In the event of a serious incident with the release of radioactive materials, this is unacceptably a lot.
Another potential source of threat is household items containing radioactive materials. Contrary to popular belief, there are a lot of them. The overall decline in education in the country leads to the fact that some irresponsible citizens are treated with Chinese “scalar radiation” medallions containing thorium-232 and giving radiation radiation up to 10 microsievert per hour (1000 micro-roentgen) - constantly wear these close to the body deadly. It is possible that some alternatively gifted are forced to wear such “healing” medallions of their children.
Also in everyday life you can meet watches and other dial gauges with continuous radioactive light mass, glassware from uranium, some types of welding electrodes with thorium with a composition, glowing grids of old tourist lamps made of a mixture of thorium and cesium, old lenses with optics, with an antireflective composition based on thorium.
Industrial sources may include gamma sources used as level meters in quarries and gamma flaw detectors, smoke detectors on the americium-241 isotope (plutonium-1 was used in the old Soviet RID-239), which emit enough control sources for army dosimeters .
The cheapest household dosimeters cost about 5 000 - 10 000 rubles. In their capabilities, they roughly correspond to Soviet and post-Soviet household dosimeters used by the population after the Chernobyl accident, and capable of detecting only gamma radiation. Slightly more expensive and high-quality models, costing about 10 000 - 25 000 rubles like Radeks MKS-1009, Radioscan-701A, MKS-01CA1, made on the basis of Geiger-Muller end mica counters, allow determining alpha and beta radiation it is extremely important in some situations, primarily to determine the surface contamination of products or the detection of radioactive household items.
The cost of professional models, including those with scintillation crystals, immediately goes for 50 000 - 100 000 rubles, only specialists working with radioactive materials on duty owe them (however, after buying the first dosimeter there is a chance to become a radiophile or radiophobe, and then the cost of professional models will no longer seem so sky-high).
At the other end of the scale there are primitive crafts - various trinkets, Chinese set-top boxes for the smartphone via the 3,5 mm connector, radiation detection programs from the smartphone’s camera and the like. Their use is not only useless, but also dangerous, because they give a false sense of confidence, and they will most likely show the presence of radiation only when the plastic of the case begins to melt.
You can also quote advice from one excellent Articles at the choice of dosimeters:
Do not take the instrument with a small upper measuring limit. For example, devices with a limit of 1000 mcr / h very often when “meeting” powerful sources are reset or show low values, which can be extremely dangerous. Focus on the upper limit (exposure dose rate) of at least 10000 mcr / h (10 mr / h or 100 mcv / h), and preferably 100000 mcr / h (100 mr / h or 1 mSv / h).
The conclusion in this situation can be drawn as follows. The presence of a dosimeter in the arsenal of an average citizen, although not necessary, is highly desirable. The problem is that the radiation threat is not detected by other means than the dosimeter - it cannot be heard, felt, tasted. Even if the whole world abandons nuclear power plants, which is extremely unlikely, there will remain medical and industrial sources of radiation that cannot be avoided in the foreseeable future, which means there will always be a risk of radioactive contamination. There will also be various household and industrial items containing radioactive substances. This is especially true for those who like to carry various trinkets home from dumps, markets or antique shops.
Do not forget that the authorities in some situations tend to play down or hush up the consequences of man-made incidents. For example, in one of the instructions on the leakage of chemically hazardous substances, a phrase like: “In some cases, to prevent panic, notifying the population about the leak of toxic substances is considered inappropriate.”
Examples of real measurements
As an example, we measured the background radiation in one of the industrial zones of the Tula region, and also checked some potentially interesting household items. The measurements were carried out by a 701A model dosimeter provided by Radiaskan (my old Bella dosimeter ordered a long life, possibly the Geiger-Muller counter SBM-20 lost its tightness).
In general, the radiation background in the region, in the city and in residential premises is about 9-11 micro-roentgen per hour, in some cases the background is deviated to 7-15 micro-roentgen per hour. In search of foci of radiation, measurements were made in the industrial zone, where various garbage of technogenic origin was buried for a long period. The measurement results did not reveal any sources of radiation, the background is close to natural.
Similar results were obtained at nearby measurement points (a total of about 50 measurements were made). Only one collapsed brick wall, most likely from the old garage, showed a slight excess - approximately 1,5-2 times the value of the natural background.
Of household items, luminous tritium key rings were first tested. The radiation from the larger key fob was of the order of 46 microroentgen per hour, which is four times higher than the background value. A small keychain gave approximately 22 micro-x-rays per hour. When carried in a bag, these key rings are completely safe, but on the body I would not recommend wearing them, as well as giving them to children who can try to disassemble them.
Something similar could be expected from tritium charms, another harmless porcelain figurine provided to me by a friend. The results of measurements of a porcelain cat showed radiation above 1000 microroentgen per hour, which is already quite significant. Most likely the radiation comes from enamel containing uranium, which was mentioned at the beginning of the article. The maximum radiation is fixed on the "back" of the figure, where the thickness of the enamel is maximum. It is hardly worth putting this "kitty" on the bedside table.
I was most impressed, also provided by a friend, aviation tachometer with numbers and arrows coated with radium paint. The maximum recorded radiation was almost 9000 micro-roentgen per hour! The radiation level confirms the data indicated at the beginning of the article. Both radioactive objects are of particular danger in case of shedding of a radioactive substance and its ingress into the body, for example, in the event of a fall and destruction.
Both radioactive objects - a porcelain cat and a tachometer, being wrapped in plastic bags, several layers of food foil, and put into another plastic bag, gave radiation in excess of 280 microroentgen per hour. Fortunately, radiation is already reduced to a safe 23 microroentgen per hour in half a meter.
Dangerous incidents with radioactive materials
In conclusion, I would like to recall several incidents with radioactive sources, one of which occurred in the USSR, and the other in sunny Brazil.
In the 1981 year in one of the apartments of the house number 7 on the street. The Guardsmen-Kantemirovtsev died an eighteen-year-old girl, who had recently been distinguished for her exemplary health. A year later, her sixteen-year-old brother died in the hospital, and a little later, their mother. The empty apartment was handed over to a new family, but after a while their teenage son also mysteriously fell ill with an incurable ailment and went into another world. The cause of death of all these people was leukemia, in a popular way - blood cancer. The doctors attributed the illnesses in the second family to bad heredity, without associating them with a similar diagnosis from the previous owners of the apartment.
Shortly before the death of a teenager, a carpet was hung on the wall in his room. When the young man had already passed away, his parents suddenly noticed that a burnt spot had formed on the carpet. The father of the deceased guy obtained a thorough investigation. When the experts who visited the apartment turned on the Geiger counter, they ran out in shock and ordered the house to be evacuated - the radiation in the house exceeded the maximum permissible level hundreds of times!
Arriving experts in protective suits found a capsule embedded in the wall with the strongest radioactive substance Cesium-137. The ampoule had dimensions of only four by eight millimeters, however, it emitted two hundred x-rays per hour, irradiating not only these apartments, but also three adjacent apartments. Specialists removed a piece of the wall with a radioactive ampoule and the gamma radiation in the 7 house immediately disappeared, and finally it became safe to live in it.
The investigation showed that in the Karan granite quarry, a similar radioactive capsule was lost in the late seventies. Probably, she accidentally fell into stones, from which they built a house. According to the charter, the quarry workers had to search at least the entire mine, but find a dangerous part, however, apparently, no one did it.
In the period from 1981 to 1989, six residents died from radiation in this house, four of whom were minors. Seventeen more people received disabilities.
On 13 of September 1987 of the year in the hot Brazilian city of Goyenia, two men named Roberto Alves and Wagner Pereira, taking advantage of the lack of protection, crawled into an abandoned hospital building. Having dismantled the medical installation for scrap, they loaded its parts into a wheelbarrow and drove it home to Alves. That evening, they began to disassemble the movable head of the device, from where they extracted a capsule with cesium-137 chloride.
Not paying attention to nausea and a general deterioration in well-being, friends went about their business. Wagner Pereira nevertheless went to the hospital that day, where he was diagnosed with food poisoning, and Roberto Alves the next day continued to disassemble the capsule. Despite the strange burns he received, on September 16 he successfully poked a hole in the capsule window and took out a strange glowing powder on the tip of a screwdriver. Trying to set fire to it, he subsequently lost interest in the capsule and sold it to a dump in a man named Dever Ferreira.
On the night of September 18, Ferreira saw a mysterious blue light emanating from the capsule, and then dragged it to his home. There he showed a luminous capsule to his relatives and friends. One of the friends of 21 on September broke the window of the capsule, pulling out several granules of the substance.
24 of September, Ferreira’s brother - Ivo carried the luminous powder to his home, scattering it on the concrete floor. His six-year-old daughter was crawling on this floor, enthusiastically smearing herself with an unusual luminous substance. In parallel, Ferreira’s wife, Gabriela, became seriously ill, and on 25 on September Ivo resold the capsule to a nearby scrap metal collection point.
However, Ferreiro Gabriela, having already received a lethal dose of radiation, compared her illness, similar ailments from her acquaintances, and a strange thing brought by her husband. On 28 of September, she found the strength to go to the second landfill, pull out the ill-fated capsule and go to the hospital with her. At the hospital, they were horrified to quickly recognize the purpose of the strange part, but fortunately, the woman packed the radiation source and the infection in the hospital was minimal. Gabriela died on October 23 on the same day as Ferreira's little niece. In addition to them, two more landfill workers died, disassembled the capsule to the end.
Only due to a combination of circumstances the consequences of this incident turned out to be local, potentially they could affect a huge number of people in a densely populated city. In total, 249 people, 42 buildings, 14 machines, 3 bush, 5 pigs were infected. The authorities removed the topsoil from the places of infection and cleaned the area with ion-exchange reagents. Ivo's little daughter had to be buried in an airtight coffin under the protests of local residents who did not want to bury her radioactive body in the cemetery.