The table below is an updated version of a similar table in IEER’s report, The Nuclear Power Deception (1996), which has more information on nuclear reactors and reactor accidents.
| Reactor type | Location | Accident type | Year | Iodine-131 release, curies | Comments |
|---|---|---|---|---|---|
| Light water reactor, BWR | Fukushima, Japan | Cooling system failure, hydrogen explosion | 2011 | 2.4 million (as of March 25, 2011) | |
| Sodium-cooled fast breeder | Monju, Japan | major secondary sodium leak | 1995 | secondary sodium was not radioactive; reactor was in test phase; extensive sodium contamination in plant | |
| Heavy water moderated and cooled, CANDU type | Narora, Uttar Pradesh, India | turbine fire; emergency core cooling system operated to prevent meltdown system | 1993 | apparently no release of radioactivity | |
| Graphite-moderated, water cooled | Chernobyl, Ukraine | supercriticality, steam explosion and graphite fire | 1986 | 7 million, perhaps far greater (see text) | Safety experiment went awry; total release 50 to 80 million curies or more; potential for continuing large releases exists |
| Light water reactor, PWR type | Three Mile Island, near Harrisburg, U.S. | cooling system failure, partial meltdown | 1979 | 13 to 17 | secondary containment prevented release of millions of curies of I-131; accident developed over several hours |
| Sodium-cooled fast breeder | Lagoona Beach (near Detroit) U.S. | cooling system block, partial meltdown | 1966 | release confined to the secondary containment | reactor was being tested for full power, but did not reach it; four minutes from indication of negative reactivity to meltdown |
| Light water reactor, BWR | near Idaho Falls, U.S. | accidental supercriticality followed by explosion and destruction of the reactor | 1961 | 80 | small U.S. Army experimental reactor using HEU fuel; 3 operators were killed |
| Heavy water cooled and moderated reactor | Chalk River, Canada | lack of coolant for a fuel element | 1958 | radioactivity apparently contained within building | Highest worker dose 19 rem |
| Graphite-moderated, gas-cooled | Sellafield, Britain | graphite fire | 1957 | 20,000 | |
| Heavy water moderated, light water cooled, experimental reactor | Chalk River, Canada | inadvertent supercriticality and partial meltdown | 1952 | “There was some release of radioactivity” | President Jimmy Carter helped in the clean-up |
Full references for the original table are available in IEER’s report Nuclear Power Deception.