Info
Reference information and guides
Nuclear Accidents
Documented nuclear accidents and incidents
Showing 8 of 8 accidents
Japan
Date
1999-09-30
Facility
JCO Fuel Fabrication Plant
Description
Criticality accident during uranium processing exposed workers and nearby residents.
Casualties
2 workers died, ~439 people exposed to radiation
Brazil
Date
1987-09-13
Facility
Abandoned INCA radiotherapy clinic
Description
Caesium-137 from an abandoned radiotherapy unit was scavenged and spread, contaminating hundreds.
Casualties
4 killed, 249 contaminated
USA
Date
1979-07-16
Facility
United Nuclear Corporation Mill
Description
Largest release of radioactive material in US history — dam failure released 94 million gallons of radioactive waste into the Puerco River.
Casualties
Long-term contamination, no immediate deaths
USA
Date
1978-10-17
Facility
Idaho National Engineering Laboratory
Description
Accidental nuclear criticality during plutonium recovery operations.
Casualties
No deaths reported
USA
Date
1961-01-03
Facility
SL-1 Stationary Low-Power Reactor
Description
Steam explosion killed 3 operators after a control rod was manually withdrawn too far.
Casualties
3 killed
United Kingdom
Date
1957-10-10
Facility
Windscale Pile 1
Description
Fire in a graphite-moderated reactor released radioactive contamination across the UK and Europe.
Casualties
Estimated 240 cancer cases linked to the release
Russia
Date
1957-09-29
Facility
Mayak Production Association
Description
Chemical explosion in a nuclear waste tank released highly radioactive material over a wide area.
Casualties
~200 cancer deaths estimated; 10,000+ evacuated
Canada
Date
1952-12-12
Facility
Chalk River NRX Reactor
Description
Reactor core destroyed by partial meltdown after operator error opened multiple valves.
Casualties
No direct deaths; contaminated water released