1957, Oct 7
A Fire in the Windscale plutonium production reactor N of Liverpool, England, released radioactive material; later blamed for 39 cancer deaths.
1961, Jan 3
A reactor at a federal instalation near Idaho Falls, Idaho, USA, killed 3 workers. Radiation was contained.
1966, Oct 5
A sodium cooling system malfunction caused a partial meltdown at the Enrico Fermi demonstration breeder reactor, near Detroit, Michigan, USA. Radiation was contained.
1969, Jan 21
A coolant malfunction from an experimental underground reactor at Lucens Vad, Switzerland, released a large amount of radiation into a cavern, which was then sealed.
1975, Mar 22
Fire at the Brown's Ferry reactor in Decatur, Alabama, USA, caused dangerous lowering of cooling water levels.
1979, Mar 28
The worst commercial nuclear accident in the U.S. occurred as equipment failures and human mistakes led to a loss of coolant and partial core meltdown at the Three Mile Island reactor in Middleton, Pennsylvania.
1981, Feb 11
Eight workers were contaminated when over 100,000 gallons of radioactive coolant leaked into the containment building of TVA's Sequoyah 1 plant in Tennessee, USA.
1981, Apr 25
Some 100 workers were exposed to radiation during repairs of a nuclear plant at Tsuruga, Japan
1986, Jan 6
A cylinder of nuclear material burst after being improperly heated at a Kerr-McGee plant at Gore, Oklahoma, USA. One worker died, 100 were hospitalized.
1986, Apr 26
In the worst accident in the history of nuclear power, fires and explosions resulting from an unauthorized experiment at the Chernobyl nuclear power plant near Kiev, USSR (now in Ukraine), left at least 31 dead in the immediate aftermath and spread radioactive material over much of Europe. An estimated 135,000 people were evacuated from areas around Chernobyl, some of which were uninhabitable for years.
1999, Sep 30
Japan's worst nuclear accident ever occurred at a uranium-reprocessing facility in Tokaimura, north-east of Tokyo, when workers accidently overloaded a container with uranium, thereby exposing workers and area residents to extremely high radiation levels.