How many accidents occurred at nuclear power plants in the world. Nuclear disasters of the world

For the first time in history, major radiation accidents occurred during the development of nuclear materials for the first atomic bombs. And a significant part of modern radioactive contamination The territory of the Earth is associated with daily activities and accidents at the enterprises of the nuclear weapons complex in various countries, most of all in the USSR, USA and Great Britain.

September 1, 1944. USA, Tennessee, Oak Ridge National Laboratory

The first victims of the Manhattan Project appeared in the United States as a result of the race to acquire nuclear weapons. While trying to unclog a pipe in a laboratory uranium enrichment device, an explosion of uranium hexafluoride occurred. The steam pipe collapsed. The incoming water vapor combined with hexafluoride, which led to the formation of a hazardous substance - hydrofluoric acid. Five people who were at that time in the laboratory suffered from acid burns and inhalation of a mixture of radioactive and acid fumes. Two of them died and the rest were seriously injured (Kramish, 1995).

USSR, Chelyabinsk-65, Combine No. 817 (PA "Mayak")

The first major radiation accident in the USSR. At an industrial nuclear reactor for the production of weapons-grade plutonium, the very next day after it reached its design capacity, due to insufficient cooling of several uranium blocks, their local fusion with the surrounding graphite, the so-called goat, occurred. The reactor was shut down, and within nine days the "nagging" channel was cleared by manual reaming. During the liquidation of the accident, all male personnel of the reactor were overexposed. Then the soldiers of the construction battalions, who were stationed near the plant, were involved in the work. In fact, these people were the first Soviet "liquidators" (Grabovsky, 2002)

New accident at the first Soviet nuclear reactor for the production of weapons-grade plutonium for the first Soviet atomic bomb... This time, the reactor was not shut down: it was required to fulfill the plan for plutonium at any cost. The liquidation of the consequences of the accident was carried out on the operating equipment, which led to the overexposure of emergency workers (Grabovsky, 2001).

A unique operation to repair the core of the first Soviet nuclear reactor for the production of weapons-grade plutonium. In violation technical regulations damaged uranium blocks were manually lifted into the central hall of the reactor, and after repairs were loaded into new channels. In total, more than 39 thousand blocks were replaced. During a month and a half of work, the entire personnel of the facility was overexposed - about 60 percent of the reactor workers received doses from 25 to 100 roentgens, and more than 30 percent - from 100 to 400 roentgens (Slavsky, 1993; Kruglov, 1995).

The first Ural radiation disaster. Mass discharge of high-level liquid radioactive waste by the Mayak plant into the Techa river. In just 21 months (from March 1949 to November 1951), at least 75 million were thrown into the river. cubic meters radioactive waste with a total activity of 2.75 million Ci. To a greater or lesser extent, about 124 thousand people were exposed to radiation in 41 settlements. The most intense exposure - 28,100 people who lived in coastal settlements along the Techa River (average individual dose - 210 mSv). Some of them had cases of chronic radiation sickness. About 37 percent of people with such a diagnosis had an accumulated dose of red bone marrow of more than 0.5 Gy, about 27 percent - more than 0.7 Gy, and 18 - more than 1 Gy (up to 4 Gy) (Lystsov, 1992; Ilyin, 2002).

September 11, 1957. USA, city of Denver, "Rocky Flats" enterprise for the production of plutonium

The first of three major fires occurred at the Rocky Flats plutonium production facility, located 27 kilometers from Denver. The fire started as a result of the ignition of metallic plutonium in the glove box. Through the ventilation system, the fire spread to the entire factory building. An attempt by firefighters to suppress it with carbon dioxide failed.

The ventilation filters on the pipes, designed to trap plutonium aerosols, burned out. A cloud of smoke, laden with radioactive material, rose 160 feet. Fire fighters used water for extinguishing. 30 thousand gallons of it with unfiltered radioactive impurities ended up in the local sewer. The fire lasted for about 13 hours. The amount of plutonium dumped is not known exactly. According to various estimates, it ranged from 14 to 250 kilograms. A few days later, although many of the plant's buildings were heavily contaminated, plutonium production work continued (List of nuclear accidents, 2004).

Second Ural radiation accident. Due to a malfunction in the cooling system, the temperature in the tank located in the radioactive waste storage facility at the Mayak PA (event of the 6th level on the INES international scale) jumped to 350 "C, which led to the evaporation of water and the subsequent explosion. Power of its specialists estimated at 70-100 tons of TNT equivalent. The concrete lid of a container 2.5 meters thick was thrown at a distance of 25-30 meters. The total release of radioactivity amounted to about 20 million Ci. Of these, almost 2 million Ci rose to a height of one kilometer and fell on the area As a result, the so-called East Ural radioactive trace was formed on the territory of a part of the Chelyabinsk, Sverdlovsk and Tyumen regions. tens to several hundred roentgens per hour, there were fire and military units, a regiment of military builders and a prison camp. more than 5 thousand people have undergone the gene. In the elimination of the consequences of the accident in the period from 1957 to 1959, from 25 thousand to 30 thousand servicemen participated, (Novoselov, Tolstikov, 1995; Larin, 1996; Larin, 2001).

October 10, 1957. Great Britain, Windscale, weapons-grade plutonium production facility

A major accident at one of the two British reactors for the production of weapons-grade plutonium (an event of the 5th level on the INES scale). Due to an error made during operation, the temperature of the fuel in the reactor rose sharply, and a fire broke out in the core, which lasted for 4 days. 150 technological channels were damaged, which entailed the release of radionuclides through a 125-meter pipe. In total, about 11 tons of uranium burned out.

The main amount of radionuclides was thrown out when they tried to cool the reactor using a jet of air, and then when extinguishing the fire with water supplied by a pump to the reactor. Radioactive fallout has contaminated vast areas of England and Ireland. In London, 500 kilometers from Windscale, the background radiation has increased 20 times. By the evening of October 11, the radioactive cloud had reached Belgium and Denmark; On the 12th - Germany; 15th - southern Norway.

The British authorities did not evacuate residents living near the plant, although they were exposed to radiation, ten times higher than allowable norms... The only protective measure for the population was the destruction of approximately 2 million liters of milk produced in a contaminated area of ​​more than 500 square kilometers. The maximum doses of radiation to the thyroid gland of people living 5 kilometers from the reactor were estimated at 1 cGy for adults and 10 cGy for children. The accident showed serious flaws in the design of the reactor. The combination of flammable graphite in the core of a nuclear reactor and air as its coolant constituted a kind of incendiary bomb.

British Prime Minister G. McMillan concealed the reasons for the incident. He feared that the evidence that the fire was due to operator negligence and reactor design flaws could undermine public confidence in the nuclear power program and slow the development of British nuclear weapons. MacMillan later stated that complete and open information"Would put national security at risk." Only 25 years later, hidden information about the consequences of the accident and their impact on the health of the population became open. Independent experts estimate that the accident caused over 1,000 deaths. To prevent negative attitudes towards the enterprise, the British Atomic Energy Agency renamed the Windscale nuclear complex to Sellafield. But today it also evokes no less gloomy associations (The New Ecologists, 1978; Berkhout, 1991; Bellona, ​​2001; Bellona, ​​2004).

November 20, 1959. USA, Tennessee, Oak Ridge National Laboratory

An explosion at the Oak Ridge laboratory radiochemical plant during decontamination work technological equipment... This resulted in the release of approximately 15 grams of plutonium-239. The buildings of the plant, as well as the surrounding area, were extensively contaminated (List of nuclear accidents, 2004).

Spring, 1967. USSR, Chelyabinsk region, Chelyabinsk-65, (PA "Mayak")

The third Ural radiation incident Accidental wind transfer of radioactivity from the shores of Lake Karachay, which PA Mayak used to discharge liquid radioactive waste. In the period from 1962 to 1966, due to the lack of sufficient rainfall, the lake began to gradually decrease. In April 1967, part of the reservoir dried up and about 5 hectares of its bottom were exposed. That began that spring strong winds carried radioactive dust, as a result, an area of ​​1,800 square kilometers was contaminated. Basically, the dust carried radioactive isotopes of cesium and strontium, the activity of which was approximately estimated at 600 Ci. The territory where about 40 thousand people lived was subjected to pollution (Kuznetsov, 2001).

Second major fire at Rocky Flats plutonium production facility. This fire, like the first in September 1957, began with the spontaneous combustion of metallic plutonium in the glove box. The fire then spread to other production equipment. A cloud of radioactive smoke covered the surrounding areas. In total, the fire burned about 5 kilograms of plutonium (RAC Report, 1999; List of nuclear accidents, 2004).

Third major fire at Rocky Flats. Spontaneous combustion of plutonium in a container. The territory of the plant and leeward areas near it were contaminated with plutonium. Several factory buildings were so contaminated that they were deemed unserviceable and later dismantled. The economic damage from the incident was approximately $ 45 million (List of nuclear accidents, 2004).

A major fire and two explosions at a plutonium production plant. An indeterminate amount was dispersed inside and outside the plant, leading to the closure of the plant (Lutins, 2004).

A chemical explosion occurred in the process tank while extracting americium-241 from radioactive waste. Radioactive material splashed in the face of the worker who was in control of the process. Within a few minutes, he inhaled more than 300 μCi of americium-241, which exceeded the maximum permissible value by several dozen times.The man was so contaminated with radioactive substances that the entire period of treatment had to live in a concrete room without windows in a special decontamination center. For a while, all his feces were collected and disposed of as radioactive waste. The local press called the victim "Atomic Man". It took five months to cleanse his skin to remove external contamination, and to use experimental drugs to reduce internal contamination of the body. As a result of the incident, the worker nearly went blind, but lived for about ten more years and died of heart disease at the age of 75 (McCluskey, 2001).

In 1969 there was an accident in an underground nuclear reactor in Lucens (Switzerland). The cave where the reactor was located, contaminated with radioactive emissions, had to be permanently walled up. In the same year, an accident occurred in France: a 500 MW launched reactor exploded at the Saint Lawrence NPP. It turned out that during the night shift the operator inadvertently loaded the fuel line incorrectly. As a result, some of the elements overheated and melted, about 50 kg of liquid nuclear fuel flowed out.

January 18, 1970 there was a radiation catastrophe at the Krasnoe Sormovo plant (Nizhny Novgorod). During the construction of the nuclear submarine K 320, an unauthorized launch of the reactor took place, which worked at an exorbitant power for about 15 seconds. At the same time, radioactive contamination of the zone of the workshop in which the ship was built occurred.

There were about 1000 workers in the shop. Radioactive contamination of the area was avoided due to the closed nature of the workshop. On that day, many went home without receiving the necessary decontamination treatment and medical assistance. Six victims were taken to a Moscow hospital, three of them died a week later with a diagnosis of acute radiation sickness, the rest were taken to a non-disclosure agreement for 25 years.

The main work to eliminate the accident continued until April 24, 1970. More than a thousand people took part in them. By January 2005, 380 of them remained alive.

Seven o'clock fire March 22, 1975 the reactor at the Browns Ferry nuclear power plant in the USA (Alabama) cost $ 10 million. It all happened after a worker with a lighted candle in his hand climbed to seal the air leak in concrete wall... The fire was picked up by the draft and spread through the cable duct. The nuclear power plant was put out of order for a year.

The most serious incident in the nuclear power industry in the United States was the accident at the Threemile Island nuclear power plant in Pennsylvania, which occurred March 28, 1979... As a result of a series of equipment malfunctions and gross errors of operators, 53% of the reactor core melted at the second power unit of the NPP. Inert radioactive gases - xenon and iodine - were released into the atmosphere. In addition, 185 cubic meters of weakly radioactive water was discharged into the Sukuahana River. 200 thousand people were evacuated from the area exposed to radiation.

On the night of April 25-26, 1986 at the fourth unit of the Chernobyl nuclear power plant (Ukraine), the largest nuclear accident in the world occurred, with the partial destruction of the reactor core and the release of fission fragments outside the zone. According to experts, the accident occurred due to an attempt to perform an experiment to remove additional energy during the operation of the main nuclear reactor. 190 tons of radioactive substances were released into the atmosphere. 8 out of 140 tons of radioactive fuel from the reactor ended up in the air. Other hazardous substances continued to leave the reactor in a fire that lasted almost two weeks. People in Chernobyl were exposed to radiation 90 times more than when the bomb fell on Hiroshima. As a result of the accident, radioactive contamination occurred within a radius of 30 km. The territory of 160 thousand square kilometers is polluted. The northern part of Ukraine, Belarus and the west of Russia were affected. 19 Russian regions with an area of ​​almost 60 thousand square kilometers and a population of 2.6 million people were exposed to radiation pollution.

September 30, 1999 the largest accident in the history of nuclear power in Japan occurred. At the plant for the manufacture of fuel for a nuclear power plant in the scientific town of Tokaimura (Ibaraki Prefecture), an uncontrollable chain reaction began due to personnel error, which lasted for 17 hours. 439 people were exposed to radiation, 119 of them received a dose exceeding the annual allowable level. Three workers received critical doses of radiation. Two of them died.

August 9, 2004 there was an accident at the Mihama nuclear power plant, located 320 kilometers west of Tokyo on the island of Honshu. In the turbine of the third reactor, there was a powerful release of steam with a temperature of about 200 degrees Celsius. The NPP employees who were nearby received serious burns. At the time of the accident, there were about 200 people in the building where the third reactor is located. No leakage of radioactive materials as a result of the accident was found. Four people died, 18 were seriously injured. The accident became the most serious in terms of the number of victims at a nuclear power plant in Japan.

March 11, 2011 Japan was hit by the most powerful earthquake in the country's history. As a result, a turbine was destroyed at the Onagawa nuclear power plant, a fire broke out, which was quickly eliminated. The situation at the Fukushima-1 NPP is very serious - as a result of the shutdown of the cooling system, nuclear fuel melted in the reactor of Unit 1, a radiation leak was detected outside the unit, and an evacuation was carried out in a 10-kilometer zone around the NPP. The next day, March 12, the media reported about the explosion at the nuclear power plant, NHK TV showed a photo showing the destroyed wall of the block.

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in Sosnovy Bor, it turns out, there were also OO accidents:

An accident occurred with the release of a large amount of radioactive substances. It was caused by the melting of several fuel elements in one of the technological channels, which led to the partial destruction of the reactor core of the first power unit. 1.5 million Ci of radioactivity were released into the external environment. Residents of the surrounding areas were not notified of the danger. It was an incident of the third level on the INES scale (Medvedev, 1989; Belluna, 2004).

An unauthorized increase in the reactor power, which led to the melting of 12 fuel elements, contamination of the core with cesium-137 and the release of radioactive substances outside the nuclear power plant (Yablokov, 2000).

May 20, 2004. Russia, Leningrad Region, Sosnovy Bor, Leningrad NPP

Emergency shutdown of the fourth power unit of the nuclear power plant and release of radioactive steam. The reason is unauthorized pressing of the emergency button in the operating room of the fourth power unit. There were no casualties; for 2 hours, the vapor cloud moved towards the settlement of Kaporye (Accidents at the NPP, 2005).

Despite the fact that nuclear energy does provide people with carbon-free energy at reasonable prices, it also shows its dangerous side in the form of radiation and other disasters. The International Atomic Energy Agency evaluates accidents at nuclear facilities on a special 7-point scale. The most serious events are classified in the highest category - seventh, while the 1st level is regarded as minor. Based on this system for assessing nuclear disasters, we offer a list of the five most dangerous accidents at nuclear facilities in the world.

Time will tell what category the accident at Fukushima-1 will assign to the rock. Photo: japantimes.co.jp

1st place. Chernobyl. USSR (now Ukraine). Rating: 7 (major accident)

The accident at the nuclear facility in Chernobyl is recognized by all experts as the worst disaster in the history of nuclear power. It is the only nuclear accident that has been classified by the International Atomic Energy Agency as the worst it can be. The largest man-made disaster broke out on April 26, 1986, at the 4th block of the Chernobyl nuclear power plant, located in the small town of Pripyat. The destruction was explosive, the reactor was completely destroyed, and in environment was thrown out a large number of radioactive substances. At the time of the accident, the Chernobyl nuclear power plant was the most powerful in the USSR. 31 people died in the first three months after the accident; the long-term consequences of radiation, revealed over the next 15 years, caused the death of 60 to 80 people. 134 people suffered from radiation sickness of varying severity, more than 115 thousand people were evacuated from the 30-kilometer zone. More than 600 thousand people took part in the liquidation of the consequences of the accident. The radioactive cloud from the accident passed over the European part of the USSR, Eastern Europe and Scandinavia. The station permanently ceased its work only on December 15, 2000.

The Kyshtym accident is a very serious radiation technogenic accident at the Mayak chemical plant located in the closed city of Chelyabinsk-40 (since the 1990s - Ozersk). The accident got its name Kyshtym for the reason that Ozersk was classified and was absent on maps until 1990, and Kyshtym is the city closest to it. On September 29, 1957, due to the failure of the cooling system, an explosion occurred in a container with a volume of 300 cubic meters, which contained about 80 m³ of highly radioactive nuclear waste. An explosion, estimated at tens of tons in TNT equivalent, destroyed the container, concrete floor 1 meter thick, weighing 160 tons, was thrown aside, about 20 million curies of radiation were released into the atmosphere. Some of the radioactive substances were lifted by the explosion to a height of 1-2 km and formed a cloud consisting of liquid and solid aerosols. Within 10-11 hours, radioactive substances fell out over a distance of 300-350 km in the northeast direction from the explosion site (in the direction of the wind). More than 23 thousand square kilometers were in the zone contaminated with radionuclides. On this territory there were 217 settlements with more than 280 thousand inhabitants, the closest to the epicenter of the disaster were several factories of the Mayak plant, a military town and a prison colony. To eliminate the consequences of the accident, hundreds of thousands of military personnel and civilians were involved, who received significant doses of radiation. The territory, which was exposed to radioactive contamination as a result of the explosion at the chemical plant, was named "East Ural radioactive trace". The total length was about 300 km, with a width of 5-10 km.

From the memoirs from the website oykumena.org: “Mom began to get sick (there were frequent fainting, anemia) ... I was born in 1959, there were the same health problems ... We left Kyshtym when I was 10 years old. I am a bit of an unusual person. During my life, strange things happened ... I foresaw the crash of the Estonian liner. And she even talked about the collision of planes with a friend of the flight attendant ... She died. "

3rd place. Windscale Fire, UK. Rating: 5 (accident with environmental risk)

On October 10, 1957, operators at Windscale Station noticed that the reactor temperature was steadily rising, while the opposite should be the case. First of all, everyone thought about the malfunction of the reactor equipment, which two workstations went to inspect. When they got to the reactor itself, they saw to their horror that it was on fire. At first, the workers did not use the water, because the plant operators expressed fears that the fire was so hot that the water would disintegrate instantly, and as you know, hydrogen in water could cause an explosion. All the means tried did not help, and then the station employees opened the hoses. Thank God the water was able to stop the fire without any explosion. According to some estimates, in the UK, Windscale has caused cancer in 200 people, half of whom have died. The exact number of victims is unknown as the British authorities tried to cover up this disaster. Prime Minister Harold Macmillan feared that the incident could undermine public support for nuclear projects. The problem of counting the victims of this disaster is aggravated by the fact that the radiation from Windscale has spread for hundreds of kilometers throughout northern Europe.

4th place. Three Mile Island, USA. Rating: 5 (accident with environmental risk)

Before the Chernobyl accident, which happened seven years later, the Three Mile Island nuclear power plant accident was considered the largest in the history of world nuclear power and is still considered the worst nuclear accident in the United States. On March 28, 1979, early in the morning, there was a major accident at the 880 MW (electrical) reactor block 2 at the Trimile Island nuclear power plant, located twenty kilometers from Harrisburg, Pennsylvania and owned by the Metropolitan Edison company. Unit 2 at the Threemile Island NPP, as it turned out, was not equipped with an additional safety system, although such systems are available at some units of this NPP. Despite the fact that the nuclear fuel partially melted, it did not burn through the reactor vessel and radioactive substances, basically, remained inside. According to various estimates, the radioactivity of noble gases released into the atmosphere was from 2.5 to 13 million curies, but the release of hazardous nuclides, such as iodine-131, was insignificant. The territory of the station was also contaminated with radioactive water flowing out from the primary circuit. It was decided that there was no need to evacuate the population living near the station, but the authorities advised pregnant women and children to leave the 8-kilometer zone. preschool age... Officially, the work to eliminate the consequences of the accident was completed in December 1993. Decontamination of the station territory was carried out, fuel was unloaded from the reactor. However, part of the radioactive water has been absorbed into the concrete of the containment and this radioactivity is almost impossible to remove. The plant's other reactor (TMI-1) was reopened in 1985.

5th place. Tokaimura, Japan. Rating: 4 (accident without significant environmental risk)

On September 30, 1999, the most terrible atomic tragedy for the Land of the Rising Sun took place. Japan's worst nuclear accident took place over a decade ago, though it was outside of Tokyo. For a nuclear reactor that has not been used for more than three years, a batch of highly enriched uranium was prepared. The plant operators were not trained in how to handle such highly enriched uranium. Not understanding what they mean by possible consequences, The "specialists" put much more uranium in the tank than needed. Moreover, the reactor vessel was not designed for this type of uranium. ... But the critical reaction cannot be stopped, and two out of three operators who worked with uranium at that time die from radiation. After the disaster, about a hundred workers and those who lived nearby were hospitalized with a diagnosis of radiation exposure, 161 people who lived several hundred meters from the nuclear power plant were subject to evacuation.

At the very end of the 18th century, radioactive radiation was discovered, after which an active study of this phenomenon began. Already in 1901, radiation was first used for medical purposes. Thirty years later, they began to think about the development of nuclear weapons. The first plutonium production plants started operating in 1944. The waste material was initially simply dumped into the environment like regular garbage. The surrounding area suffered significant damage. This is how statistics were born radiation accidents in the world. The era of radioactive contamination of the environment by humans has begun.

Peaceful "atom"

From the middle of the 20th century, the development of the engine began for its use in the transport industry. As this direction developed, they tried to develop an atomic-jet, an atomic-engine, an atomic-powered ship. The most successful was the idea to create nuclear powered ships. In the civilian sphere, these are nuclear icebreakers,.

In medicine, radiation began to serve the good almost immediately after its discovery. Today, radioactive radiation is effectively used in the field of neurology, oncology, cardiology, as well as complex diagnostics.

Statistics of radiation accidents in the world in the field of the national economy:

Years	Ejection type, conventional* qty
	Unorganized dumping of nuclear waste	Industrial accidents and other leaks	Civil incidents
1944–1949	2	4	–
1950–1959	1	15	–
1960–1969	1	11	–
1970–1979	1	10	–
1980–1989	1	28	1
1990–1999	2	31	15
2000–2009	2	10	9

* - the table contains conditional quantitative values. So, for example, only at the "Mayak" enterprise (Chelyabinsk region, Russia), about 32 incidents of varying severity are known over the entire period of operation, and only 15 of them were included in the summary statistics.

From the table, you can see that since the 90s, incidents began to occur among citizens. Cases of theft of nuclear materials and attempts to sell them have become more frequent (the culprits, in most cases, are soon from the radiation received). In particular, medical radioactive sources were stolen and disassembled and sold as scrap metal. In general, various materials “contaminated” with radiation have more than once got to the enterprises for the remelting of scrap metal.

Nuclear disasters

After the discovery of the chain reaction of decay in 1941, they thought about using the nuclear resource for generating electricity. In 1954, the world's first nuclear power plant was completed (Obninsk, USSR). Nowadays, there are about 200 power plants on the planet. However, it is difficult to ensure the trouble-free operation of such facilities.

In order to assess the degree of danger of the data of statistics of radiation accidents in the world in 1990, INES was developed - an international classification of nuclear events in the civil sphere. According to this scale, major radiation accidents in the world are accidents rated above 4 points. In the entire history of nuclear power, there are about 20 such cases.

INES 4. Events leading to the release into the environment of insignificant doses of radiation, equivalent to 10–100 TBq 131 I. In such accidents, isolated deaths from radiation are recorded. In the incident area, only food control is required. Examples of accidents:

1. Fleurus, Belgium (2006).
2. Tokaimura, Japan (1999).
3. Seversk, Russia (1993).
4. Saint Laurent, France (1980 and 1969).
5. Bohunice, Czechoslovakia (1977).

INES 5. Accidents resulting in a radiation release equivalent to 100–1000 TBq 131 I and causing several deaths. Local evacuation may be required in such areas. Examples:

1. Goiânia, Brazil (1987). An orphaned object was found, which turned out to be destroyed by a highly radioactive source of Cesium-137. Strong doses of radiation were received by 10 people, 4 of them died.
2. Chazhma Bay, USSR (1985).
3. Three Mile Island, USA (1979).
4. Idaho, USA (1961).
5. Santa Susana, USA (1959).
6. Windscale Pile, UK (1957).
7. Choke River, Canada (1952).

INES 6. Accidents in which the release of radioactive material into the environment is equivalent to 1000–10000 TBq 131 I. Evacuation of the population or shelter is required. One example is known. This is the very first radiation accident in the world of this scale - Kyshtym, USSR (1957).

Mayak is a nuclear fuel storage and processing facility in the Chelyabinsk Region. In 1957, an explosion occurred in a container containing 70–80 tons of nuclear waste. A radioactive cloud was formed, which carried hazardous substances across the territory of more than 23 thousand km 2 to the heads of 272 thousand people. For the first 10 days, about 200 people died from radiation.

INES 7. This score is assigned to the largest radiation accidents and disasters in the world. They are characterized by extensive radiation exposure to people and the environment, equivalent to a release of 10,000 TBq 131 I and more. They have colossal consequences for human health and the state of nature. There is an urgent need to implement planned and long-term countermeasures designed for such cases. This rating is assigned to two of the largest radiation accidents in the world:

1. Fukushima (2011)... Succession tragic events hit Japan that year. Fukushima-1 NPP could not resist them either. and the subsequent three reactors were left without power supply, and therefore without a cooling system. The explosion was inevitable. They were contaminated with radiation, vast territories turned out to be, the ocean waters suffered the most in the accident. The exclusion zone has become a 30-kilometer territory around the nuclear power plant. In the first year, approximately 1,000 people died from radiation sickness.
2. Chernobyl (1986)... The disaster at the Chernobyl nuclear power plant occurred on April 26. In the fourth power unit, which contained about 190 tons of nuclear fuel, an explosion thundered. The accident that began due to erroneous actions of the personnel acquired inadequate proportions due to (as it later turned out) violations committed during the construction of the reactor.

As a result, about 50 thousand km 2 of agricultural land became unsuitable for cultivation. The city of Pripyat, whose population at that time was 50 thousand people, fell into the 30-kilometer exclusion zone. As well as other settlements.

The statistics of radiation accidents show that in the next twenty years about 4 thousand people died from radiation.

Military "atom"

They began to think about the development of nuclear weapons since 1938. In 1945, for the first time in the world, the United States tested a nuclear bomb on its territory, and then dropped two more on the cities of Japan: Hiroshima and Nagasaki. More than 210 thousand people were killed.

According to Wikipedia, the city of Hiroshima was completely rebuilt in 1960. During the period from 1945 to 2009, 62 nuclear weapons tests and 33 accidents of military equipment using nuclear power plants as an engine or with nuclear weapons on board are known.

Years	Ejection type, qty..
	Weapon Test	Accidents military equipment
1945–1949	2	–
1950–1959	13	1
1960–1969	28	9
1970–1979	12	3
1980–1989	7	7
1990–1999	–	2
2000–2009	–	11

Since the 90s, weapon testing has ceased. Since in 1996, most countries signed a nuclear test ban treaty.

Statistics of radiation accidents in the world: expert opinion

There are two opinions about the dangers of radiation. Some scientists carry out scrupulous calculations, and argue that the share of man-made radiation accidents in the world and nuclear weapons tests account for only 1% of the total radiation background. That the nuclear industry is an inexhaustible resource with the future.

According to others, the statistics of radiation accidents in the world show that, in economic terms, there are no advantages from nuclear energy. Therefore, experts call for abandoning the nuclear industry, leaving it in the past. Technologies are expensive at the design and construction stage, and the damage in the event of an accident outweighs all possible benefits. Not to mention the loss of life and the negative impact of radiation on the health of many generations to come.

NPP - nuclear equipment for generating electricity that operates under specified conditions and conditions. It is a nuclear reactor connected to various systems necessary for the implementation of its full and safe work. Accidents at nuclear power plants are large-scale man-made disasters. Despite the fact that they generate electricity in an environmentally friendly way, the consequences of failure are felt all over the world.

Why are nuclear power plants dangerous?

Nuclear power plants location world map

An accident at a power plant occurs due to errors in the maintenance of the system, wear and tear of equipment, or due to natural Disasters... Breakdowns due to design errors occur at the initial stages of NPP startup and are much less common. The most common human factor in emergencies. Equipment malfunctions are accompanied by the release of radioactive particles into the environment.

The emission power and the degree of pollution of the surrounding area depend on the type of breakdown and the time it takes to eliminate the malfunction. The most dangerous situations are associated with overheating of reactors due to a malfunction of the cooling system and depressurization of the fuel rod housing. In this case, radioactive vapors are released through the ventilation pipe into the external environment. Accidents at power plants in Russia do not go beyond hazard class 3 and are minor incidents.

Radiation disasters in Russia

The largest accident occurred in the Chelyabinsk region in 1948 at the Mayak plant during the commissioning of a plutonium-fueled nuclear reactor at the capacity set by the design. Due to poor cooling of the reactor, several blocks of uranium combined with graphite located around them. The liquidation of the incident lasted 9 days. Later, in 1949, hazardous liquid contents were discharged into the Techa River. The population of 41 points located nearby was affected. In 1957, a man-made disaster called "Kushtymskaya" took place at the same plant.

UKRAINE. Chernobyl exclusion zone.

In 1970, in Nizhny Novgorod, during the production of an atomic vessel at the Krasnoye Sormovo plant, the prohibited launch of a nuclear reactor took place, which began to operate at prohibitive power. The fifteen-second failure caused the contamination of the closed area of ​​the workshop, the radioactive contents did not get outside the territory of the plant. The liquidation of the consequences lasted 4 months, most of the liquidators died due to an excess of radiation.

Another man-made accident was hidden from the public. In 1967 there was biggest disaster ALVZ-67, as a result of which the population of the Tyumen and Sverdlovsk regions suffered. The details were hidden, and little is known about the incident to date. Contamination of the territory occurred unevenly, foci appeared in which the coverage density exceeded 50 curies per 100 km. Accidents at power plants in Russia are local in nature and do not pose a danger to the population, these include:

• a fire at the Beloyarsk NPP in 1978 due to the fall of the overlap on the oil tank of the turbine generator, in 1992 due to the negligence of employees when pumping radioactive components for subsequent specialized cleaning;
• pipeline rupture in 1984 at the Balakovo NPP;
• when the power supply sources of the Kola NPP are de-energized due to a hurricane;
• failures in the operation of the reactor in 1987 at the Leningrad NPP with the release of radiation outside the station, minor failures in 2004 and 2015. without global consequences for the environment.

In 1986, an accident occurred at a global power plant in Ukraine. Part of the active reaction zone was destroyed, as a result of a global catastrophe, the western part of Ukraine, 19 western regions of Russia and Belarus were contaminated with radioactive substances, and the 30-kilometer zone became uninhabitable. The outbursts of active content lasted for almost two weeks. Explosions at nuclear power plants in Russia have not been recorded over the entire period of the existence of nuclear power.

The risk of breakdowns at nuclear power plants is calculated according to the IAEA International Scale. Conventionally, man-made disasters can be divided into two levels of danger:

• lower level (1-3 class) - minor failures that are considered incidents;
• middle level (4-7 class) - significant malfunctions, which are called accidents.

The widespread consequences are caused by incidents of hazard class 5-7. Breakdowns below the third class are most often dangerous only for plant personnel due to contamination of internal premises and radiation exposure of employees. The probability of a global catastrophe is 1 in 1-10 thousand years. The most dangerous accidents at nuclear power plants are classified as class 5-7, and it is they that cause negative consequences for the environment and the population. Modern nuclear power plants have four degrees of protection:

• a fuel matrix that does not allow the decay products to leave the radioactive shell;
• a radiator shell that protects the ingress of hazardous substances into the circulation circuit;
• the circulation loop does not allow the radioactive contents to flow out under the containment;
• a complex of shells called containment.

The outer dome protects the premises from the release of radiation outside the station, this dome can withstand a shock wave equal to 30 kPa, so an explosion of a nuclear power plant with global emissions is unlikely. At which nuclear power plants are explosions most dangerous? The most dangerous incidents are considered when ionizing radiation is released outside the reactor safety system in an amount exceeding the parameters specified in the design documentation. They are called:

• the uncontrolled nuclear reaction inside the unit and the inability to control it;
• failure of the heating element cooling system;
• the appearance of a critical mass due to overloading, transportation and storage of used components.

According to the International Nuclear Event Scale, all nuclear incidents are graded on an 8-level system. For 2011, 2 accidents were assessed at level 7 Chernobyl and Fukushima One at level 6 (Kyshtym accident)

The Fukushima-1 nuclear power plant accident is a major radiation accident (according to Japanese officials - level 7 on the INES scale) that occurred on March 11, 2011 as a result of the strongest earthquake in Japan and the subsequent tsunami

Chernobyl Chernobyl accident level 7

At about 1:24 am on April 26, 1986, an explosion 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, with the deaths of 2 people - the operator of the main circulation pump (main circulation pump) Valery Khodemchuk (the body was not found, heaped up under the rubble of two 130-ton drum separators) and the employee of the commissioning enterprise Vladimir Shashenok (died of a spinal fracture and numerous burns at 6:00 in the Pripyat Medical Station, in the morning of April 26). A fire broke out in various rooms and on the roof. Subsequently, the remains of the core melted. A mixture of molten metal, sand, concrete and fuel fragments spread over the sub-reactor rooms. As a result of the accident, radioactive substances were released into the environment, including isotopes of uranium, plutonium, iodine-131 (half-life 8 days), cesium-134 (half-life 2 years), cesium-137 (half-life 33 years), strontium -90 (half-life 28 years).

The highest doses were received by about 1000 people who were near the reactor at the time of the explosion and who took part in emergency work in the first days after it. These doses ranged from 2 to 20 gray (Gy) and were found to be fatal in some cases.
There were 134 cases of acute radiation sickness among people performing emergency work on the fourth block. In many cases, radiation sickness was complicated by radiation burns of the skin caused by β-radiation. During 1986, 28 people died from radiation sickness. Two more people died in the accident for reasons unrelated to radiation, and one died, presumably from coronary thrombosis. During 1987-2004, another 19 people died, but their deaths were not necessarily caused by radiation sickness.
The untimeliness, incompleteness and inconsistency of the official information about the disaster gave rise to many independent interpretations. Sometimes the victims of the tragedy are considered not only citizens who died immediately after the accident, but also residents of the adjacent regions who went to the May Day demonstration, not knowing about the accident. With this calculation, the Chernobyl disaster significantly exceeds the atomic bombing of Hiroshima in terms of the number of victims.
As a result of the accident, about 5 million hectares of land were withdrawn from agricultural use, a 30-kilometer exclusion zone was created around the nuclear power plant, hundreds of small settlements were destroyed and buried (buried with heavy equipment).
The world nuclear power industry suffered a serious blow as a result of the Chernobyl accident. 1986 to 2002 in North America and Western Europe not a single new nuclear power plant was built, which is due both to the pressure of public opinion and to the fact that insurance premiums have increased significantly and the profitability of nuclear energy has decreased.

In the USSR, the construction and design of 10 new nuclear power plants was mothballed or stopped, the construction of dozens of new power units at operating nuclear power plants in different regions and republics was frozen.
Large areas of contaminated territories remained outside the 30-kilometer zone, and since the 1990s, a gradual resettlement of settlements in the Polesskiy region, in which the pre-emergency level of radionuclide contamination exceeded the norms established by law, was carried out. So, by 1996, the township was finally resettled. Polesskoe, town. Vilcha, s. Dibrova, s. New World and many others. Since 1997, this territory has become part of Chernobyl zone, was transferred under the control of the Ministry of Emergencies and included in the security perimeter.
The exclusion zone of the Chernobyl nuclear power plant is a territory prohibited for free access, which has been intensively contaminated with long-lived radionuclides as a result of the accident at the Chernobyl nuclear power plant.

The Chernobyl zone includes the north of the Ivankovsky district of the Kiev region, where the power plant itself is located, the cities of Chernobyl and Pripyat, the north of the Polessky district of the Kiev region (including the village of Polesskoye and the village of Vilcha), as well as part of the Zhytomyr region up to the border with Belarus.

Kyshtym Kyshtym accident level 6

The "Kyshtym accident" is a major radiation technogenic accident that occurred on September 29, 1957 at the Mayak chemical plant, located in the closed city of Chelyabinsk-40. Now this city is called Ozersk. The accident is called Kyshtym because the city of Ozersk was classified and was absent on maps until 1990. Kyshtym is the nearest town to it.

On September 29, 1957, at 16:22, due to the failure of the cooling system, an explosion occurred in a container with a volume of 300 cubic meters, which contained about 80 m³ of highly radioactive nuclear waste. An explosion, estimated at tens of tons in TNT equivalent, destroyed the container, a 1-meter-thick concrete ceiling weighing 160 tons was thrown aside, about 20 million curies of radioactive substances were thrown into the atmosphere.
Some of the radioactive substances were lifted by the explosion to a height of 1-2 km and formed a cloud consisting of liquid and solid aerosols. Within 10-11 hours, radioactive substances fell out over a distance of 300-350 km in the northeast direction from the explosion site (in the direction of the wind). The territory of several enterprises of the Mayak plant, a military town, a fire station, a prisoner colony and then an area of ​​23,000 square kilometers were found in the zone of radiation contamination. with a population of 270,000 people in 217 settlements in three regions: Chelyabinsk, Sverdlovsk and Tyumen. Chelyabinsk-40 itself was not injured. 90 percent of radiation contamination fell on the territory of ZATO (closed administrative-territorial unit of the Mayak chemical plant), and the rest dispersed further.

During the liquidation of the consequences of the accident, 23 villages from the most polluted areas with a population of 10 to 12 thousand people were resettled, and buildings, property and livestock were destroyed. To prevent the spread of radiation in 1959, by a government decision, a sanitary protection zone was created on the most contaminated part of the radioactive trace, where any economic activity was prohibited, and since 1968 the East Ural State Reserve was formed on this territory. Now the contamination zone is called the East Ural Radioactive Trace (EURT).

To eliminate the consequences of the accident, hundreds of thousands of military personnel and civilians who received significant doses of radiation were involved.

Accident at the Three Mile Island nuclear power plant level 5

The Three Mile Island accident is one of the largest accidents in the history of nuclear power, which occurred on March 28, 1979 at the Three Mile Island nuclear power plant located on the Susquehanna River near Harrisburg, Pennsylvania. , USA).

Before the Chernobyl accident, which happened seven years later, the accident at the Three Mile Island nuclear power plant was considered the largest in the history of world nuclear power and is still considered the most severe nuclear accident in the United States, during which the reactor core was seriously damaged, part of the nuclear fuel melted.
The accident at the Three Mile Island nuclear power plant occurred a few days after the release of the movie China Syndrome, the plot of which is based on an investigation of problems with the reliability of a nuclear power plant, conducted by a TV journalist and an employee of the station. One of the episodes shows an incident very similar to what actually happened on Three Mile Island: an operator, deceived by a faulty sensor, turns off the emergency water supply to the core and this almost leads to its melting (to " Chinese Syndrome "). In another coincidence, one of the characters in the film says that such an accident could lead to the evacuation of people from an area "the size of Pennsylvania."

Although the nuclear fuel was partially melted, it did not burn through the reactor vessel and the radioactive material remained mostly inside. According to various estimates, the radioactivity of noble gases released into the atmosphere was from 2.5 to 13 million curies (480 × 1015 Bq), but the release of hazardous nuclides, such as iodine-131, was insignificant. The territory of the station was also contaminated with radioactive water flowing out from the primary circuit. It was decided that there was no need to evacuate the population living near the station, but the Governor of Pennsylvania advised pregnant women and preschool children to leave the five-mile (8 km) zone.
The work to eliminate the consequences of the accident began in August 1979 and was officially completed in December 1993. They cost US $ 975 million. Decontamination of the station territory was carried out, fuel was unloaded from the reactor. However, part of the radioactive water has been absorbed into the concrete of the containment and this radioactivity is almost impossible to remove.

The plant's other reactor (TMI-1) was reopened in 1985.

Accident at the plant "Krasnoe Sormovo" level 5

A radiation accident at the Krasnoye Sormovo plant - occurred at the Krasnoye Sormovo plant on January 18, 1970 during the construction of the nuclear submarine K-320 of project 670 Skat.
During the construction of the nuclear submarine K-320, when it was on the slipway, an unauthorized launch of the reactor took place, which worked at prohibitive power for about 15 seconds. At the same time, there was a significant radioactive contamination of the territory of the workshop in which the ship was being built. There were about 1000 workers in the shop. Radioactive contamination of the area was avoided due to the closed nature of the workshop. On that day, many went home without receiving the necessary decontamination treatment and medical assistance. Six of the victims were taken to a hospital in Moscow, three of them died a week later with a diagnosis of acute radiation sickness, the rest were taken to a non-disclosure agreement for 25 years. Only the next day the workers began to be washed with special solutions. On the same day, 450 people, having learned about the incident, quit their jobs, the rest had to take part in eliminating the consequences of the accident. The main work to eliminate the accident continued until April 24, 1970. More than a thousand people took part in them.

For participation in the liquidation of the accident, none of them received government awards.
By January 2005, out of more than a thousand participants, 380 people remained alive. Of the benefits, they have only a small allowance from the regional authorities (330 rubles a month until January 1, 2010, 750 rubles - from January 1, 2010). They cannot receive a higher status as employees of the special risk unit due to the absence of the law. The new owner of the Krasnoye Sormovo plant does not bear any responsibility for the accident that happened then.

Accident in the Chazhma bay level 5

The radiation accident in the Chazhma Bay is an accident of a nuclear power plant on a nuclear submarine of the Pacific Fleet, which resulted in human casualties and radioactive contamination of the environment.
On August 10, 1985, the nuclear submarine K-431 of project 675, located at pier No. 2 of the Navy shipyard in Chazhma Bay (Shkotovo-22 settlement), was recharging the reactor cores. The work was carried out in violation of the requirements of nuclear safety and technology: non-standard lifting devices were used. The starboard reactor was recharged normally.

When the reactor lid was blown up (lifted), an uncontrolled spontaneous chain reaction of uranium fission of the left side reactor occurred at the moment of passing by the torpedo boat, which exceeded the permissible speed in the port.

As a result, a thermal explosion of the reactor occurred, killing 8 officers and 2 sailors. In the center of the explosion, the radiation level, according to scientists, was 90,000 roentgens per hour, which led to the instant death of those who were there. A fire started on the submarine, which was accompanied by powerful emissions of radioactive dust and steam. According to expert Alexei Mityunin, the entire active part of the reactor was eventually thrown out of the boat. Eyewitnesses who extinguished the fire spoke of large tongues of flame and puffs of brown smoke that escaped from a technological hole in the boat's hull.

The extinguishing was carried out by untrained employees - workers of the shipyard and the crews of neighboring boats. At the same time, there was no work clothes or special equipment. It took about two and a half hours to put out the fire. Specialists of the emergency fleet team arrived at the scene of the emergency three hours after the explosion. As a result of uncoordinated actions of the parties, the liquidators stayed in the contaminated area until two o'clock in the morning, waiting for a new set of clothes to replace the infected one.

An information blockade was set at the scene of the accident, the plant was cordoned off, and the plant's access control was strengthened. In the evening of the same day, the village was disconnected from outside world... At the same time, no preventive and explanatory work with the population was carried out, as a result of which the population received a dose of radiation exposure.

It is known that as a result of the accident 290 people were injured. Of these, ten died at the time of the accident, ten had acute radiation sickness, and thirty-nine had a radiation reaction. Since the enterprise is a secure one, it was mainly servicemen who suffered, who were among the first to start eliminating the consequences of the disaster.

Radioactive contamination in Goiania level 5

Radioactive contamination in Goiânia is a case of radioactive contamination that occurred in the Brazilian city of Goiânia.

In 1987, a part from a radiotherapy installation containing the radioactive isotope cesium-137 in the form of cesium chloride was stolen from an abandoned hospital by looters, after which it was thrown away. But after some time, it was discovered in a landfill and attracted the attention of the owner of the landfill, who then brought the found medical source radiation to his house and invited neighbors, relatives and friends to look at the powder glowing with blue light. Small fragments of the source were taken in hands, rubbed with them on the skin, passed on to other people as gifts, and as a result, the spread of radioactive contamination began. For more than two weeks, more and more people came into contact with powdered cesium chloride, and none of them knew about the danger associated with it.

As a result of the wide distribution of highly radioactive powder and its active contact with various objects, a large amount of radiation-contaminated material accumulated, which was later buried in a hilly area of ​​one of the outskirts of the city, in the so-called near-surface storage. This area can only be used again after 300 years.

The Goiânia accident has attracted international attention. Prior to the 1987 accident, regulations governing the control of the spread and movement of radioactive substances used in medicine and industry around the world were relatively weak. But after the incident in Goiânia, the attitude to these issues was overhauled. Subsequently, the revised and amended standards and concepts began to be really implemented at the household level, and stricter control was established over their observance. The IAEA has introduced strict safety standards for radioactive sources, namely International Basic Safety Standards No. 115, the development of which was co-sponsored by several international organizations. Today in Brazil there is a licensing requirement for each source, which allows its life cycle to be traced back to final disposal.

Windscale Graphite Fire Level 5

The Windscale fire is a major radiation accident that occurred on October 10, 1957, at one of the two reactors of the Sellafield nuclear complex in Cumbria in the North West of England.

As a result of a fire in an air-cooled graphite reactor for the production of weapons-grade plutonium, a large (550-750 TBq) release of radioactive substances occurred. The accident is level 5 on the International Nuclear Event Scale (INES) and is the largest in the history of the UK nuclear industry
The accident occurred during the execution of the scheduled annealing of the graphite stack. During normal operation of the reactor, neutrons bombarding the graphite lead to a change in its crystal structure.
The consequences of the accident were studied by the National Commission on Radiological Protection. According to the assessment made by the commission, about 30 additional deaths from cancer could occur among the population (0.0015% increase in deaths from cancer), that is, during the time during which these 30 deaths can occur, among exposed people, according to statistics, about 1 million people

Accident at the Tokaimura nuclear facility level 4

The accident at the Tokaimura nuclear facility occurred on September 30, 1999 and resulted in the death of two people. At the time, it was the most serious incident in Japan involving the peaceful use of nuclear energy. The accident happened at a small JCO radiochemical plant, a division of Sumitomo Metal Mining, in Tokai Village, Naka County, Ibaraki Prefecture
As a result of the workers' actions at 10:45 am, about 40 liters of a mixture containing about 16 kg of uranium were found in the sump. Although the theoretical value of the critical mass of even pure uranium-235 is 45 kg, in solution the real critical mass is much lower compared to solid fuel due to the fact that the water in the solution acts as a neutron moderator; in addition, the water jacket around the sump played the role of a neutron reflector. As a result, the critical mass was significantly exceeded and a self-sustaining chain reaction began.

A worker who was adding the seventh bucket of uranyl nitrate to the sump and partially hanging over it saw a blue flash of Cherenkov radiation. He and another worker near the sump immediately experienced pain, nausea, difficulty breathing, and other symptoms; a few minutes later, already in the decontamination room, he vomited and lost consciousness.

There was no explosion, but the result of the nuclear reaction was intense gamma and neutron radiation from the sump, which triggered the alarm, after which actions began to localize the accident. In particular, 161 people out of 39 were evacuated. residential buildings within a radius of 350 meters from the enterprise (they were allowed to return to their homes in two days). Eleven hours after the start of the accident, an area outside the plant recorded gamma radiation levels of 0.5 millisieverts per hour, about 1,000 times the natural background.

The chain reaction continued intermittently for about 20 hours, after which it stopped due to the fact that water, which played the role of a neutron reflector, was drained from the cooling jacket surrounding the sump, and boric acid(boron is a good absorber of neutrons); 27 workers took part in this operation, who also received some dose of radiation. The breaks in the chain reaction were caused by the liquid boiling up, the amount of water becoming insufficient to reach criticality, and the chain reaction was dying out. After cooling and condensation of water, the reaction was resumed.

However, some of the radioactive noble gases and iodine-131 still got into the atmosphere.
Three workers who directly worked with the solution were heavily irradiated, having received doses: one from 10 to 20 sievert, another from 6 to 10 sievert, the third from 1 to 5 sievert (despite the fact that in 50% of cases, a dose of about 3-5 sievert is fatal ). The first died after 12 weeks, the second after 7 months. In total, 667 people were exposed to radiation (including plant workers, firefighters and rescuers, as well as local residents), but, with the exception of the three workers mentioned above, their radiation doses were insignificant (no more than 50 millisieverts).

The thermal power of the nuclear chain reaction in the sump was subsequently estimated in the range from 5 to 30 kW. This incident was assigned level 4 on the International Nuclear Event Scale (INES). The IAEA concluded that the incident was caused by "human error and serious disregard for safety principles."