Major Nuclear Accidents

Chalk River (Canada): A reactor shutoff rod failure, combined with several operator errors, led to a major power excursion of more than double the reactor's rated output at AECL's NRX reactor

Windscale Pile (UK): Release of radioactive material to the environment following a fire in a reactor core.

Kyshtym (Russia): Significant release of radioactive material to the environment from explosion of a high activity waste tank.

Jaslovské Bohunice (Czechoslovakia): Damaged fuel integrity, extensive corrosion damage of fuel cladding and release of radioactivity.

Three Mile Island (US): Severe damage to the reactor core

Saint Laurent des Eaux (France): Melting of one channel of fuel in the reactor with no release outside the site

Chernobyl (Ukraine): Widespread health and environmental effects. External release of a significant fraction of reactor core inventory.

Tomsk (Russia): Pressure buildup led to an explosive mechanical failure

Tokaimura (Japan): Fatal overexposures of workers following a criticality event at a nuclear facility

Fleurus (Belgium): Severe health effects for a worker at a commercial irradiation facility as a result of high doses of radiation

Fukushima (Japan): Reactor shutdown after the 2011 Sendai earthquake and tsunami; failure of emergency cooling caused an explosion