Nuclear accidents

The risk and consequences of nuclear accidents is a heavily debated topic. Various techniqual measures and work routines have been adopted to reduce the risk of accidents and minimize the negative impact when an accident do occur, but accidents are still happening and some of them have serious effects.

Examples of nuclear accidents

  • Chernobyl disasterThe Chernobyl disaster (April 26, 1986)This disaster occured in Chernobyl, Kiev Oblast, Ukraininan SSR, Soviet Union. Fuel rods in reactor #4 of the Chernobyl power plant overheated, which led to an explosion and a meltdown. Radioactive material was dispersed over large parts of Europe. 30 direct deaths.
  • The Fukushima Daiichi disaster (March 11, 2001)This disaster occured at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Japan. A tsunami damaged the plant’s five active reactors, and loss of electrical power led to overheating and meltdowns. 2 direct deaths.
  • The Kyshtym disaster (September 29, 1957)

This disaster occured at the nuclear fuel reprocessing plant Mayak in Ozyorsk,, a closed city located near Kyshtym in Russia, Soviet Union. The cooling system in a tank containing 70+ tons of liquid radioactive waste failed. The temperature rose, resulting in evaporation, and eventually an explosion of dried waste. The explosion released an estimated 800 PBq of radioactivity.

  • The Sellafield fire (October 10, 1957)

A fire at the British atomic bomb project in Sellafield, Cumberland, United Kingdom destroyed the core and released an estimated 740 terabecquerels of iodine-131. Fortunately, a rudimentary smoke filter on the main chimney prevent the leak from becoming bigger. It is therefore not considered a disaster.

  • The accident at the Lucens reactor (January 21, 1969)

A loss-of-coolant accident occured at the experimental Lucens reactor in Vaud, Switzerland, and this resulted in a partial core meltdown. Fortunately, the cavern – which had been heavily contaminated with radioactive material – was sealed quickly, which prevented the incident from from becoming a disaster.

  • The Thre Mile Island accident (March 28, 1979)

A loss-of-coolant accident occured at reactor #2 of the Three Mile Island Nuclear Generating Station near Harrisburg in Pennsylvania, United States, and resulted in a partial core meltdown. In total approximately 93 PBq of radioactive gases, and approximately 560 GBq of iodine-131 was released into the environment.

Examples of nuclear-powered submarines involved in nuclear accidents

  • Soviet submarine K-19 in 1961
  • Soviet submarine K-11 in 1965
  • Soviet submarine K-27 in 1968
  • Soviet submarine K-140 in 1968
  • Soviet submarine K-429 in 1970
  • Soviet submarine K-222 in 1980
  • Soviet submarine K-431 in 1985 0

Examples of accidents involving radiotherapy

  • The 1990 Clinic of Zaragoza radiotherapy accident in Spain.
  • The 1996 radiotherapy accident at San Juan de Dios Hospital in San José, Costa Rica.