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Chernobyl NPP Named after V.I. Lenin

Location: Ukraine Start of construction: May 1970 Start of operation: September 26, 1977 End of operation: December 15, 2000 Operating organization: State Specialized Enterprise "Chernobyl Nuclear Power Plant"

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Pripyat

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April 26 marks 25 years since that fateful night when an accident occurred in a small Ukrainian town that shocked the whole world. Then the peoples of the Earth felt the full force of the "peaceful atom". This "peaceful atom", scattered over many thousands of square kilometers due to someone's irresponsibility, left - and there is no getting around - it will still leave a sad mark on the fate of thousands of people.

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Chronicle of events

01:24 There were 2 explosions. One was a steam explosion, the other was the result of fuel vapors. The explosions gave access to the air reactor. The air reacted with the graphite substance and created carbon monoxide. This flammable gas ignited and set fire to the reactor. More than 8 tons of fuel broke free, which contains plutonium and other highly radioactive decay products, as well as radioactive graphite substance. These materials were sprayed around the accident site. In addition, cesium fumes were released by the explosion and subsequent fire.

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They were the first...

Vashchuk Nikolay Vasilyevich Titenok Nikolai Ivanovich Kibenok Viktor Nikolaevich Pravik Vladimir Pavlovich Tishura Vladimir Ivanovich Ignatenko Vasily Ivanovich

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Scientific data on the consequences of the Chernobyl accident

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Participants in the liquidation of the consequences of the accident

About 200 thousand Russians took part in the liquidation of the consequences of the accident The diagnosis of "acute radiation sickness" was confirmed in 134 liquidators, 28 of them died in the first months (firefighters from the Chernobyl nuclear power plant). Another 16 people died over the course of 17 years from a variety of causes, including heart attacks and road accidents. To date, 90 people are alive, 20 of them have been diagnosed with radiation cataracts.

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In the cohort of liquidators, 145 cases of leukemia were detected, of which 50 were caused by the radiation factor (the probability of death from leukemia reaches 90%). The peak incidence of leukemia among the liquidators was recorded in 1992-1995. After 1996, the incidence rate of leukemia among the liquidators has been steadily decreasing and approaching the spontaneous level. The liquidators also revealed 55 cases of thyroid cancer, of which 12 were attributed to the effects of the radiation factor (on modern level medicine, the probability of death from thyroid cancer is less than 3-5%).

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Today, 27% of the liquidators have a disability. This is a very high percentage considering that the average age of liquidators is currently 48-49 years old. But the absence of increased mortality among the liquidators and the dependence of the frequency of disability on the dose received are evidence that the effect of increased disability most likely has social causes.

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Population

In Russia, the total area of ​​contaminated territories amounted to more than 59 thousand square meters. km., including 2.9 million hectares of agricultural land and about 1 million hectares of forest land. Almost 1 million people continue to live in these territories. 800 thousand citizens More than 52 thousand people were resettled from radioactively contaminated territories in an organized manner or resettled themselves

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The first type of cancer to spread five years after the accident was thyroid cancer, followed by leukemia. But, by analogy with Hiroshima, 15-40 years after the Chernobyl accident, doctors expect an explosion of cancers, especially cancers of the mammary glands, stomach and intestines. And one more thing: only in the first generation, that is, the first twenty years after the accident, every three days in Belarus, Russia and Ukraine a child is born with physical and mental disabilities, because his father or mother was irradiated.

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Genetic changes caused by radiation injury

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Pripyat 25 years later...

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Chernobyl disaster in the Tula region

More than 2.5 thousand Tula residents took part in the fight against the consequences of the Chernobyl disaster. More than 900 thousand inhabitants of our region and more than half of the territory of the Tula region suffered from radiation exposure. The Chernobyl cloud swept over the Tula land, leaving its mark in 2,40 settlements in 18 administrative districts with a population of more than 900,000 people. The total area of ​​radioactive contamination of the region was 14.5 thousand square kilometers. 56% of the territory of the region and half of its population were exposed to radiation in one way or another. “More than 667 thousand people currently live in the contaminated territories, including 29.2 thousand people with the right to resettlement. More than 3.5 thousand citizens in the region

• On April 26, 1986, at 1:24 am, two explosions were heard in succession at the 4th power unit of the Chernobyl nuclear power plant, which announced to the whole world about the accomplished tragedy of the outgoing century. There was a powerful man-made disaster at a nuclear facility.

• The explosions led to the complete destruction of the reactor and its core, cooling systems, and the building of the reactor hall.
• Reinforced concrete and metal structures, graphite blocks and their pieces were thrown onto the roof of the turbine hall, into the area around the nuclear power plant.

• From the mouth of the reactor rose, several hundred meters high, a column of combustion products, a powerful stream of gaseous radioactivity. From 190 tons nuclear fuel 90% got into the earth's atmosphere. According to scientists, the release of radionuclides is, according to various estimates, four or more explosions in Hiroshima.

• There is no roof, part of the wall is destroyed ... The lights went out, the phone turned off. Coverings are crumbling. Paul is trembling. The rooms are filled with either steam, or fog, dust. Short circuit sparks flash. Radiation control devices go off scale. Hot radioactive water flows everywhere.

• At 1:30 a.m., divisions of fire departments for the protection of the nuclear power plant, the station itself and the city of Pripyat arrived at the crash site, under the command of lieutenants Viktor Kibenok (left) and Vladimir Pravik. Firefighters took on the full power of radioactive radiation when extinguishing a fire on the roof of the engine room. Later, fire brigades arrived from Chernobyl, Kyiv and other regions, commanded by Major Telyatnikov. By 5 o'clock in the morning the fire was localized

• Both and their subordinates received high doses of radiation, they could not be saved.
• Both were awarded the title of Hero of the Soviet Union posthumously. All of them are buried at the Mitinsky cemetery in Moscow.

• Thousands of people from all over former USSR were called up and sent to eliminate the consequences of the disaster. Work on the liquidation of the accident was carried out mainly manually.

• They removed the top layer of soil on the territory of the nuclear power plant with shovels, threw pieces of reinforcement, graphite from the roof of the turbine hall with their hands, washed off the radioactive dirt with rags inside the station.

• Some radio-controlled mechanisms that perform work to remove blockages could not withstand the high level of radiation and went out of control of the operators

• The destroyed core had contact with the atmosphere; there everything was gurgling, noisy, buzzing, like fiery hell

• The government, after listening to the advice of experts, decided to close, fill the funnel with heat-absorbing materials capable of filtering fire and ash.
• Therefore, from April 27 to May 10, the pilots of the USSR Air Force, risking their flesh and life, made hundreds of flights over the active zone. They dropped from helicopters thousands and thousands of bags of sand, clay, dolomite, boron, as well as large packages of lead, which ranked first in weight - 2,400 tons.

• The power of radiation emissions from the destroyed reactor decreased only after five days, amounting to about 15 percent of the original. Then it began to grow again, reaching (after four days) 70% of the level of the first day. Experts, baptized with horror, expected an even more severe radiation strike, which could happen when the cover of the destroyed reactor collapsed into the mine pool, and the pool was filled with water from the cooling system. Means were urgently prepared to evacuate millions of people. Hundreds of train echelons were placed on sidings. Prepared auto-mobile columns. The evacuation was supposed to be carried out within a radius of 300 kilometers from the nuclear power plant, which included the cities of Kyiv, Gomel, Bobruisk ...

• On the tenth day, the emission power fell -
• up to one percent. There was a nervous breakdown.
• In the first days, when the eruption was in full swing, air currents moved to Belarus…

• After the Chernobyl disaster, a lot of work was done to assess the contamination of territories exposed to radiation.

• Decontamination It was important to prevent the expansion of the zone of radioactive contamination. To this end, they struggled with dust formation by spraying the surface with a special mixture, using polymer coatings, using the vacuum suction cleaning method (vacuum cleaners), manually wiping objects with cloths soaked in decontaminating solutions.

• Before the accident...

• after…

• Its height was 61 meters, the greatest thickness of the walls -
• 18 meters. The erection of the "sarcophagus" was carried out with the help of self-propelled cranes equipped with television surveillance equipment. It provides for an exhaust ventilation system with air purification, a forced cooling system, and tanks with a boron solution are installed on the roof to prevent an increase in neutron activity.

• Dead city

• Silence. Silence in the dead city.
• "Rossokha" - a huge field filled with rows of corroded trucks, fire engines, bulldozers, armored personnel carriers and other radioactive equipment - and in the middle, as a symbol of complete hopelessness, helicopters drooped with their blades, which will never again be destined to take to the air ...

• You can't live here

• Under the influence of radiation, apples grew incredible sizes

• Foal with five limbs

• It is noted: exceeding the indicators of endocrine system disease and metabolic disorders, diseases of the blood and blood-forming organs,
• congenital anomalies
• more than 4 times;
• mental disorders
• and diseases of the circulatory system
• more than 2 times.

• Remember!
• 25 years ago there was an accident at the Chernobyl nuclear power plant….

Chernobyl, a city in Ukraine, on the Pripyat River, at its confluence with the Kiev reservoir. Regional center with a developed industry: an iron foundry and a cheese-making plant, a repair and maintenance base for the fleet; workshop of production and art association, medical school.

On April 25, 1986, the shutdown of the 4th power unit of the Chernobyl nuclear power plant was scheduled for the next scheduled preventive maintenance. During such shutdowns, various routine procedures and equipment tests are usually carried out.

At about 1:24 am on April 26, 1986, a release occurred at the 4th power unit of the Chernobyl nuclear power plant, which completely destroyed the reactor. The building of the power unit partially collapsed, killing 2 people.

A fire broke out in various rooms and on the roof. Subsequently, the remnants of the core melted. The accident resulted in the release of environment radioactive substances.

The accident is regarded as the largest of its kind in the history of nuclear power, both in terms of the estimated number of people killed and affected by its consequences, and in terms of economic damage. At the time of the accident, the Chernobyl nuclear power plant was the most powerful in the USSR. The real number of deaths during the first 3 months is estimated at 31 people; the long-term effects of exposure, identified over the next 15 years, caused the death of 60 to 80 people.

Unlike the bombings of Hiroshima and Nagasaki, the explosion resembled a very powerful "dirty bomb" - radioactive contamination became the main damaging factor. The radioactive cloud from the accident passed over the European part of the USSR, Eastern Europe and Scandinavia. Approximately 60% of radioactive fallout fell on the territory of Belarus. About 200,000 people were evacuated from contaminated areas.

evacuation

About 50,000 people were evacuated from the city of Pripyat alone in one day.

In the first days after the accident, the population of the 10-kilometer zone was evacuated. In the following days, the population of other settlements of the 30-kilometer zone was evacuated. It was forbidden to take things with you, many were evacuated in home clothes. In order not to fan the panic, it was reported that the evacuees would return home in three days. Pets were not allowed to be taken with them (later they were shot).

While all foreign funds mass media they talked about the threat to people's lives, and a map was shown on TV screens air currents in Central and Eastern Europe, in Kyiv and other cities of Ukraine and Belarus, festive demonstrations and festivities dedicated to May Day were held. Those responsible for withholding information subsequently explained their decision by the need to prevent panic among the population.

Elimination of the consequences of the accident

Reactor In 1986, there were 4 RBMK-1000 reactors operating at the Chernobyl nuclear power plant, with a capacity of 3200 MW each. The reactor core is a vertical cylinder with a diameter of 11.8 m and a height of 7 m. This entire volume is filled with graphite masonry with a total mass of 1850 tons. In 1986, there were 4 RBMK-1000 reactors operating at the Chernobyl nuclear power plant, with a capacity of 3200 MW each. The reactor core is a vertical cylinder with a diameter of 11.8 m and a height of 7 m. This entire volume is filled with graphite masonry with a total mass of 1850 tons.

Reactor 1872 channels pass through the reactor core. In 1661 of them there are fuel elements (TVELs) - zirconium hollow cylinders containing 200 uranium pellets. The total mass of uranium in the reactor is 190 tons. The remaining 211 cylinders contain neutron absorbing rods.

Reactor The core is surrounded by a steel tank with water, which plays the role of biological protection. Water in the cooling system circulates at a pressure of 70 atm (the boiling point at this pressure is 284 C). It is fed into the channels from below by the main circulation pumps (MCP).

Reactor Passing through the core, the water heats up and boils. The resulting mixture of 14% steam and 86% water is discharged through the upper part of the channel and enters 4 separator drums. In these gigantic (length - 30 m, diameter - 2.6 m) mechanisms, water flows down under the action of gravity, and steam is supplied to two turbines, each with a capacity of 500 MW. After passing through the turbines, the steam condenses into water at a temperature of 165C. This water, called feed water, is pumped back to the separators, mixed with water from the reactor, cools it to 270C, and goes with it to the MCP inlet. This is a closed loop of water-coolant circulation. Channels with absorber rods are cooled by an independent circuit.

Reactor In addition to the described devices, each unit also includes a control and protection system that regulates the power of the chain reaction, safety systems - in particular, an emergency reactor cooling system (ECCS) - and many others. In addition to the devices described, each unit also includes a control and protection system that regulates the power of the chain reaction, safety systems - in particular, an emergency reactor cooling system (ECCS) - and many others.

Accident On April 25, 1986, Friday, it was planned to stop the fourth block of the Chernobyl nuclear power plant for scheduled repairs. It was decided, taking advantage of this, to test one of the two turbogenerators in the run-down mode (rotation of the turbine rotor by inertia after the steam supply is stopped, due to which the generator continues to provide energy for some time). On April 25, 1986, Friday, it was planned to stop the fourth block of the Chernobyl nuclear power plant for scheduled repairs. It was decided, taking advantage of this, to test one of the two turbogenerators in the run-down mode (rotation of the turbine rotor by inertia after the steam supply is stopped, due to which the generator continues to provide energy for some time). According to the operating rules, the power supply of the most important systems of the station is repeatedly duplicated. In case of accidents when the steam supply to the turbines can be turned off, backup diesel generators are started to power some of the devices, which reach full power in 65 seconds. According to the operating rules, the power supply of the most important systems of the station is repeatedly duplicated. In case of accidents when the steam supply to the turbines can be turned off, backup diesel generators are started to power some of the devices, which reach full power in 65 seconds.

Accident An idea arose for this time to provide power to some systems, including ECCS pumps, from turbine generators rotating by inertia. However, during the first tests, it turned out that the generators stop producing current faster than expected during the freewheel. And in 1986 Institute "Dontekhenergo", in order to bypass this obstacle, has developed a special regulator of the magnetic field of the generator. They were going to check him on April 25th. It was envisaged that when the thermal power of the reactor drops to MW (hereinafter, the thermal power is indicated everywhere), the supply of steam to generator 8 will stop and its run-out will begin. In order to exclude the activation of the ECCS during the experiment, the program prescribed to block this system, and simulate the electrical load of the ECCS pumps by connecting four main circulation pumps (MCPs) to the turbogenerator. An idea arose for this time to provide power to some systems, including ECCS pumps, from turbine generators rotating by inertia. However, during the first tests, it turned out that the generators stop producing current faster than expected during the freewheel. And in 1986 Institute "Dontekhenergo", in order to bypass this obstacle, has developed a special regulator of the magnetic field of the generator. They were going to check him on April 25th. It was envisaged that when the thermal power of the reactor drops to MW (hereinafter, the thermal power is indicated everywhere), the supply of steam to generator 8 will stop and its run-out will begin. In order to exclude the activation of the ECCS during the experiment, the program prescribed to block this system, and simulate the electrical load of the ECCS pumps by connecting four main circulation pumps (MCPs) to the turbogenerator.

Accident At this point in the program, experts later saw two errors at once. First, turning off the ECCS was optional. Secondly, and most importantly, the connection of the circulation pumps to the "running out" generator directly connected, it would seem, the "electrotechnical experiment" with the nuclear processes in the reactor. If it was necessary to simulate the load, for this it was by no means possible to take the MCP, but any other energy consumers should be used. But not only that: during the experiment, the staff made deviations from this, not too thought out program.

Accident Events unfolded like this. 25th of April. 1 h 00 min. A slow reduction in reactor power has begun. 13h05 min. Power reduced to 1600 MW. Turbine generator 7 stopped. The power supply of the block systems was transferred to the turbogenerator h. 00 min. In accordance with the program, the ECCS is disabled. However, soon the Kyivenergo dispatcher demanded to delay the shutdown of the unit: the end working week, afternoon - electricity consumption is growing. The reactor continued to operate at half power. And here, in violation of the rules, the staff did not reconnect the ECCS. In fairness, we note that this did not affect the course of events.

Accident 23 h 10 min. The controller lifted his ban and the power reduction continued. 26 April. 0 h 28 min power has reached a level at which the control is supposed to be switched from local to general automatic regulation. At this moment, the young operator, who did not have experience in such modes, made a mistake and did not give the command to the control system to “hold power”. As a result, the power dropped sharply to 30 MW, due to which the boiling in the channels weakened and xenon poisoning of the core began. According to the operating rules, in such a situation, the reactor should be shut down. But then the tests would not have taken place, and the staff not only did not stop the reaction, but, on the contrary, tried to increase its power.

Accident 1 h. 00 min. The power was increased only up to 200 MW, instead of the MW prescribed by the program. Due to the ongoing poisoning, it was no longer possible to increase it, although the automatic control rods were almost completely removed from the core, and the manual control rods were raised by the operator. 1 h 03 min. The preparation of the experiment began. In addition to the six main circulation pumps, the first of the two standby ones is connected. It was decided to launch them so that after the final shutdown of the "running out" turbogenerator supplying energy to four main circulation pumps, the remaining two pumps, together with two standby ones (included in the general power grid of the station), would continue to reliably cool the core.

Accident 1 h 07 min. The second backup MCP was put into operation. Eight pumps started working instead of six. This increased the flow of water through the channels so much that there was a danger of cavitation breakdown of the MCP, and most importantly, increased cooling and further reduced the already weak vaporization. At the same time, the water level in the separator drums dropped to the emergency mark. The operation of the block became extremely unstable.

Accident 1 h 19 min. Since the water level in the separator drums was dangerously low, the operator increased the supply of feed water (condensate). At the same time, the personnel blocked the emergency shutdown signals for the reactor due to insufficient water level and steam pressure. Such a deviation from the operating regulations was not provided for by the test program. 1 hour 19 minutes 30 s. The water level in the separators began to rise. However, now, due to the influx of relatively cold feedwater into the core, steam generation there has practically ceased.

Accident 1 h 19 min. 58 p. the pressure continued to fall, and the device through which excess steam had previously been bled into the condenser closed automatically. This somewhat slowed down the pressure drop, but did not stop it. Now the count has gone to seconds. 1 hour 21 minutes 50 s. The water level in the separator drums has increased significantly. Since this was achieved by quadrupling the feedwater flow rate, the operator has now drastically reduced the supply. 1 hour 22 minutes 10 s. Less subcooled water began to flow into the circuit, and boiling increased slightly, and the level in the separators stabilized. Of course, at the same time, reactivity increased somewhat, but the automatic control rods, having slightly lowered, immediately compensated for this growth.

Accident 1 h 22 min. Z0 s. Feed water flow has dropped more than required, to 2/3 normal. This could not be prevented due to the insufficient accuracy of the control system, which was not designed to work in such a non-standard mode. According to the printout of the Skala station computer, the operational reactivity margin was already so small that it was necessary to immediately shut down the reactor. However, the personnel busy trying to stabilize the block apparently simply did not have time to study this data. 1 hour 22 minutes 45 s. The feedwater flow rate and the steam content in the channels finally equalized, and the pressure began to slowly increase. The reactor seemed to be returning to a stable regime, and it was decided to start the experiment.

Accident 1 h, 23 min, 04 s. The steam supply to turbogenerator No. 8 was shut off. At the same time, again in violation of the program and regulations, the signal for an emergency shutdown of the reactor was blocked when both turbines were turned off. 1 hour 23 minutes 10 s. Four circulation pumps, powered by a "running out" generator, began to slow down. The flow of water decreased, the cooling of the zone became weaker, and the temperature of the water at the entrance to the reactor rose. 1 hour 23 minutes, 30 seconds Boiling intensified, the amount of steam in the core increased, and now the reactivity and power began to gradually increase. All three groups of automatic control rods went down, but could not stabilize the reaction; power continued to rise slowly.

Accident 1 h 23 min. 40s. The shift supervisor gave the command to press the AZ-5 button to signal maximum emergency protection, according to which all absorber rods are immediately introduced into the zone. 1 hour 23 minutes 43 p. Self-driving has begun. The power reached 530 MW and continued to grow catastrophically. Two automatic protection systems worked in terms of power level and in terms of its growth rate, but this did not change anything, since the AZ-5 signal that each of them sends had already been given by the operator. 1 hour 23 minutes 44 p. The power of the chain reaction was 100 times higher than the nominal one. In a fraction of a second, the fuel elements became hot, the fuel particles, having broken the zirconium shells, flew apart and got stuck in graphite. The pressure in the channels increased many times, and instead of flowing (from below) into the core, water began to flow out of it.

Accident This was the moment of the first explosion. The reactor ceased to exist as a controlled system. Steam pressure destroyed part of the channels and the steam lines leading from them above the reactor. the pressure dropped, water again flowed through the cooling circuit, but now it flowed not only to the fuel rods, but also to the graphite stack. 1 hour 23 minutes 46 p. Air rushed into the core, and a new explosion was heard, as they believe, as a result of the formation of mixtures of oxygen with hydrogen and carbon monoxide. The ceiling of the reactor hall collapsed, about a quarter of the graphite and part of the fuel were thrown out. At that moment, the chain reaction stopped. Hot debris fell on the roof of the engine room and other places, creating more than 30 fires. 1 hour 30 minutes Fire brigades from Pripyat and Chernobyl left for the accident site.

What was it? Now that we know the essence of what happened at the nuclear power plant on the fateful night, it's time to think about the seemingly naive question - what was the explosion? Now that we know the essence of what happened at the nuclear power plant on the fateful night, it's time to think about the seemingly naive question - what was the explosion? Explosions are usually classified in two ways: by the nature of the stored energy itself and by the mechanism of its rapid release. By the nature of the stored energy, one can count as many types of explosions as there are types and forms of energy. The explosion of a gas cylinder when a crack appears in the shell, the explosion of a meteorite when it collides with a planet, the explosion of a conductor when a powerful current pulse flows, all these are explosions due to the energy of physical processes. In chemical explosions, the energy of interatomic bonds is released. If the energy of the atomic nucleus is released, the explosion cannot be called otherwise than nuclear. According to the mechanism of energy release, explosions are divided into thermal and chain.

What was it? The first occur in the presence of positive feedback: the more energy is released, the higher the temperature, and the higher it is, the more energy is released (as, for example, during combustion). Chain explosions are carried out in systems where energy is released in elementary acts, each of which initiates several new ones, but not through an increase in temperature, but directly, like neutrons in the fission of uranium or active radicals in chain chemical reactions. The first occur in the presence of positive feedback: the more energy is released, the higher the temperature, and the higher it is, the more energy is released (as, for example, during combustion). Chain explosions are carried out in systems where energy is released in elementary acts, each of which initiates several new ones, but not through an increase in temperature, but directly, like neutrons in the fission of uranium or active radicals in chain chemical reactions.

What was it? In all official documents, the explosion at CHAZS is called thermal. However, this refers to the mechanism. What about the nature of energy? According to this criterion, it is nuclear, because during the acceleration of the reactor, it was precisely the energy of fission of uranium nuclei that was released in the first place. In all official documents, the explosion at CHAZS is called thermal. However, this refers to the mechanism. What about the nature of energy? According to this criterion, it is nuclear, because during the acceleration of the reactor, it was precisely the energy of fission of uranium nuclei that was released in the first place. However, the issue with the mechanism is complicated. An explosion began, of course, as a thermal one: the cooling system could not cope with heat removal, the steam content increased, and the reactor power grew. But positive Feedback closes here through the chain process of uranium fission, and even when the reactor ceased to be controlled, the reaction that broke out in it, in its physical essence, was not much different from the processes in the atomic bomb. However, the issue with the mechanism is complicated. An explosion began, of course, as a thermal one: the cooling system could not cope with heat removal, the steam content increased, and the reactor power grew. But the positive feedback closes here through the chain process of uranium fission, and even when the reactor ceased to be controlled, the reaction that broke out in it, in its physical essence, was not much different from the processes in the atomic bomb. It turns out that the explosion is really nuclear? But after all, there were two explosions, and the next, the most powerful and destructive, was typically chemical. In addition, we all know that a nuclear explosion is distinguished by four damaging factors: a shock wave, penetrating radiation (gamma quanta and neutrons), light radiation and radioactive contamination. There was no shock wave and light radiation in Chernobyl, there were penetrating radiation and radioactive contamination. What to call an explosion semi-nuclear? It turns out that the explosion is really nuclear? But after all, there were two explosions, and the next, the most powerful and destructive, was typically chemical. In addition, we all know that a nuclear explosion is distinguished by four damaging factors: a shock wave, penetrating radiation (gamma quanta and neutrons), light radiation and radioactive contamination. There was no shock wave and light radiation in Chernobyl, there were penetrating radiation and radioactive contamination. What to call an explosion semi-nuclear?

What was it? On the other hand, in an atomic bomb, radioactive fragments are born immediately at the moment of explosion, while in Chernobyl, radionuclides accumulated over many months dissipated. Therefore, although the energy of mechanical destruction did not amount to even a hundred thousandth of Hiroshima, in terms of contamination with long-lived radionuclides, the Chernobyl accident is equivalent to the explosion of bombs dropped on Hiroshima. On the other hand, in an atomic bomb, radioactive fragments are born immediately at the moment of explosion, while in Chernobyl, radionuclides accumulated over many months dissipated. Therefore, although the energy of mechanical destruction did not amount to even a hundred thousandth of Hiroshima, in terms of contamination with long-lived radionuclides, the Chernobyl accident is equivalent to the explosion of bombs dropped on Hiroshima. The accident at the Chernobyl nuclear power plant defies elementary classification. And to call it a "nuclear explosion" without further clarification, and even more so to easily compare Chernobyl with Hiroshima, which some publicists are fond of, means to lead away from the truth no less than denying the nuclear nature of the accident. The accident at the Chernobyl nuclear power plant defies elementary classification. And to call it a "nuclear explosion" without further clarification, and even more so to easily compare Chernobyl with Hiroshima, which some publicists are fond of, means to lead away from the truth no less than denying the nuclear nature of the accident. The danger in an accident at a nuclear power plant is not associated with a grandiose nuclear explosion and huge destruction, but with a leak of radionuclides and contamination of the area around it. This in itself is a fairly serious threat. The danger in an accident at a nuclear power plant is not associated with a grandiose nuclear explosion and huge destruction, but with a leak of radionuclides and contamination of the area around it. This in itself is a fairly serious threat.

Get up, great country! In the city of Pripyat, located a few kilometers from the Chernobyl nuclear power plant, with a population of about 45 thousand people, the radiation level quickly reached 4-14 micro-roentgens per second and exceeded the permissible norm by more than 1000 times. In the city of Pripyat, located a few kilometers from the Chernobyl nuclear power plant, with a population of about 45 thousand people, the radiation level quickly reached 4-14 micro-roentgens per second and exceeded the permissible norm by more than 1000 times. The fire departments of the nuclear power plant were the first to extinguish the fire. Some time later, firefighters from Pripyat and other cities of the Kyiv region began to arrive. At 4.50 in the morning the fire was localized, and at 6.35 it was completely extinguished. The fire departments of the nuclear power plant were the first to extinguish the fire. Some time later, firefighters from Pripyat and other cities of the Kyiv region began to arrive. At 4.50 in the morning the fire was localized, and at 6.35 it was completely extinguished.

Get up, great country! The first at the station were the firemen of the VIth fire department of the city of Pripyat, the commanders of the departments: Vashchuk Nikolai, Ignatenko Vasily; firefighters Nikolay Titenko, Vladimir Tishure and others. None of them survived. The four named received the title of Hero of Ukraine. The first at the station were firefighters of the VIth fire department of the city of Pripyat, commanders of departments: Vashchuk Nikolay, Ignatenko Vasily; firefighters Nikolay Titenko, Vladimir Tishure and others. None of them survived. Four named received the title of Hero of Ukraine Among the first liquidators of the accident, more than 6 thousand Urals residents. Of these, about 1.5 thousand were sent not through the military registration and enlistment offices, like most conscripts and those called from the reserve, but through Minsredmash, which united all secret facilities related to the use of nuclear materials. Several hundred specialists were sent from closed cities, such as Sarov (Arzamas-16) and others. More than 6,000 people from the Urals were among the first liquidators of the accident. Of these, about 1.5 thousand were sent not through the military registration and enlistment offices, like most conscripts and those called from the reserve, but through Minsredmash, which united all secret facilities related to the use of nuclear materials. Several hundred specialists were sent from closed cities, such as Sarov (Arzamas-16) and others.

Get up, great country! A day later, the government commission decided on the need to evacuate residents of nearby settlements. In total, about 100 thousand people were evacuated. A day later, the government commission decided on the need to evacuate residents of nearby settlements. In total, about 100 thousand people were evacuated. To prevent the spread of radioactive dust into the destroyed reactor, helicopters dropped a mixture of sand, bromine and lead. By the end of the year, a reinforced concrete sarcophagus was built over the 4th unit - the so-called "Shelter" object. To prevent the spread of radioactive dust into the destroyed reactor, a mixture of sand, bromine and lead was dropped from helicopters. By the end of the year, a reinforced concrete sarcophagus was built over the 4th block - the so-called "Shelter" object

Get up, great country! There was also a threat of radioactive contamination of the Dnieper, from where the entire eastern part of Ukraine took water. In order to prevent dust from being washed into the Pripyat River, which flows into the Dnieper, the planes "shot" the clouds over several areas, and concrete fences were built along the river. There was also a threat of radioactive contamination of the Dnieper, from where the entire eastern part of Ukraine took water. In order to prevent dust from being washed into the Pripyat River, which flows into the Dnieper, the planes "shot" the clouds over several areas, and concrete fences were built along the river. Despite these efforts, two days after the accident, the radiation level in Pripyat exceeded the norm by more than 115 thousand times, and in the reactor zone by 110 thousand times. The most dangerous 30-kilometer zone - the exclusion zone - was taken under special control. Despite these efforts, two days after the accident, the radiation level in Pripyat exceeded the norm by more than 115 thousand times, and in the reactor zone by 110 thousand times. The most dangerous 30-kilometer zone - the exclusion zone - was taken under special control.

Consequences Time takes the events and facts of the Chernobyl tragedy into the past. In the modern period of development of our society, Chernobyl remains as a symbol of oversight and fear, which should be quickly forgotten. Therefore, efforts to overcome negative consequences catastrophes were often hasty and ineffective. Mistakes in legislative activity social protection affected citizens were accompanied by a violation of their constitutional rights to compensation for damage caused to health and property. Time takes away the events and facts of the Chernobyl tragedy into the past. In the modern period of development of our society, Chernobyl remains as a symbol of oversight and fear, which should be quickly forgotten. Therefore, efforts to overcome the negative consequences of the disaster were often hasty and ineffective. Mistakes in legislative activities for the social protection of affected citizens were accompanied by a violation of their constitutional rights to compensation for damage caused to health and property.

Consequences 21 years have passed since the accident at the Chernobyl nuclear power plant. What can be said now about its consequences? If you turn to the International Medical information system Medline, it is easy to find that more than 2000 scientific articles have been published on this issue. 21 years have passed since the accident at the Chernobyl nuclear power plant. What can be said now about its consequences? If we turn to the International Medical Information System Medline, it is easy to find that more than 2000 scientific articles have been published on this issue. The accident at the Chernobyl nuclear power plant has become the largest nuclear accident. In the first weeks after the accident, the radiation situation was determined mainly by iodine radionuclides and was very tense. The accident at the Chernobyl nuclear power plant has become the largest nuclear accident. In the first weeks after the accident, the radiation situation was determined mainly by iodine radionuclides and was very tense.

Consequences In some regions, dose rates reached hundreds of microR/h, and often exceeded 1 mR/h. Over large areas, an increased content of radionuclides in milk, vegetables, meat and other types of agricultural products was observed. In a number of regions, dose rates reached hundreds of microR/h, and often exceeded 1 mR/h. Over large areas, an increased content of radionuclides in milk, vegetables, meat and other types of agricultural products was observed. During this period, the predominant irradiation of the thyroid gland, which absorbs iodine radionuclides that enter the body with food and air, took place. During this period, the predominant irradiation of the thyroid gland, which absorbs iodine radionuclides that enter the body with food and air, took place.

Consequences Subsequently, with the decay of short-lived radionuclides, the radiation situation began to be determined by cesium radionuclides. Work on radiation monitoring of the country's territory was launched from the first days after the accident. In total, more than 6 million square kilometers of the territory of Russia were surveyed. On the basis of aerial gamma and ground surveys, maps were prepared and published for contamination with cesium-137, strontium-90 and plutonium-239 of the European part of Russia. Subsequently, as short-lived radionuclides decayed, the radiation situation began to be determined by cesium radionuclides. Work on radiation monitoring of the country's territory was launched from the first days after the accident. In total, more than 6 million square kilometers of the territory of Russia were surveyed. On the basis of aerial gamma and ground surveys, maps were prepared and published for contamination with cesium-137, strontium-90 and plutonium-239 of the European part of Russia.

Consequences In 1997, a multi-year European Community project to create an atlas of cesium pollution in Europe after the Chernobyl accident came to an end. According to estimates made within the framework of this project, the territory of 17 European countries with a total area of ​​thousand square meters. km turned out to be contaminated with cesium with a pollution density of over 1 Ci/sq.km. In 1997, a multi-year European Community project to create an atlas of cesium pollution in Europe after the Chernobyl accident was completed. According to estimates made within the framework of this project, the territory of 17 European countries with a total area of ​​thousand square meters. km turned out to be contaminated with cesium with a pollution density of over 1 Ci/sq.km.

Consequences Directly during the accident, more than 300 people from the NPP personnel and firefighters were exposed to acute radiation exposure. Of these, 237 were initially diagnosed with acute radiation sickness (ARS). The most seriously injured, and these are 31 people, could not be saved. Despite the measures taken to limit the exposure of participants in the work to eliminate the consequences of the accident, a significant part of them were exposed to doses of the order of the maximum allowable dose of 250 meV in 1986. Directly during the accident, more than 300 people from the NPP personnel and firefighters were exposed to acute radiation exposure. Of these, 237 were initially diagnosed with acute radiation sickness (ARS). The most seriously injured, and these are 31 people, could not be saved. Despite the measures taken to limit the exposure of participants in the work to eliminate the consequences of the accident, a significant part of them were exposed to doses of the order of the maximum allowable 250 meV in 1986.

Consequences Measures for radiation protection of the population from overexposure were started in Russia immediately after the detection of radioactive contamination. They consisted in the introduction of various restrictions, the conduct of decontamination work, the implementation of the resettlement of residents. With the clarification of the radiation situation, the area of ​​work was expanded, and the volume of emergency response measures was increased. The main activities at the initial stage were carried out in the so-called zone of strict control, limited by an isoline of 15 Ci / sq. km (about 100 thousand inhabitants of Russia). Measures for the radiation protection of the population from overexposure were started in Russia immediately after the discovery of radioactive contamination. They consisted in the introduction of various restrictions, the conduct of decontamination work, the implementation of the resettlement of residents. With the clarification of the radiation situation, the area of ​​work was expanded, and the volume of emergency response measures was increased. The main activities at the initial stage were carried out in the so-called zone of strict control, limited by an isoline of 15 Ci / sq. km (about 100 thousand inhabitants of Russia).

Consequences Changes in society and the understanding of the negative effect of numerous life restrictions initiated in the years an attempt to move to the recovery phase of the accident based on the determination of the additional dose limit for a lifetime of 350 meV. Regarding this concept in a rapidly changing society, which was then Soviet Union, a heated discussion ensued. In this situation, the Government of the USSR turned to the IAEA with a request to organize an independent examination. The results of the International Chernobyl Project, which confirmed the adequacy of the protective measures taken, could not overcome the emerging trend of aggravation of the problem. Competent organizations (NCRP of the USSR, WHO, IAEA, etc.), which focused on radiological approaches, could not fully appreciate the roles socio-psychological And political factors. Changes in society and the understanding of the negative effect of numerous life restrictions initiated in the years an attempt to move to the recovery phase of the accident on the basis of determining the limit of the additional dose per life of 350 meV. There was a heated discussion about this concept in a rapidly changing society, which was then the Soviet Union. In this situation, the Government of the USSR turned to the IAEA with a request to organize an independent examination. The results of the International Chernobyl Project, which confirmed the adequacy of the protective measures taken, could not overcome the emerging trend of aggravation of the problem. Competent organizations (NCRP of the USSR, WHO, IAEA, etc.), which were guided by radiological approaches, could not fully assess the role of socio-psychological and political factors.

Consequences In May 2000, the 49th session of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was held in Vienna. Considerable attention of this authoritative international organization was paid to the assessment of the medical consequences of Chernobyl. Among the highest UNSCEAR citation indices were Scientific research performed by the National Radiation-Epidemiological Registry, created by decree of the Government of the Russian Federation on the basis of the Medical Radiological Research Center of the Russian Academy of Medical Sciences, Obninsk. In May 2000, the 49th session of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) took place in Vienna. Considerable attention of this authoritative international organization was paid to the assessment of the medical consequences of Chernobyl. One of the highest SCEAR citation indices was noted for scientific research carried out by the National Radiation Epidemiological Registry, created by decree of the Government of the Russian Federation on the basis of the Medical Radiological Research Center of the Russian Academy of Medical Sciences, Obninsk.

Consequences The accident drastically disrupted the normal order of people's lives, and for many of them had tragic consequences. However, the vast majority of the affected population should not live in fear of serious health consequences, because favorable prospects should prevail for the health of the majority of people. The accident drastically disrupted the normal order of people's lives, and for many of them had tragic consequences. However, the vast majority of the affected population should not live in fear of serious health consequences, because favorable prospects should prevail for the health of the majority of people.