The Japanese nuclear safety agency rated the damage at a nuclear power plant at Fukushima at a
four on a scale of one to seven. (This is not quite as bad as the Three Mile Island which was rated 5.
http://www.iaea.org/Publications/Factsh ... h/ines.pdf
For reference:
LEVEL 7 - MAJOR ACCIDENT
A major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures.
* CHERNOBYL, Soviet Union (now Ukraine), 1986
LEVEL 6 - SERIOUS ACCIDENT:
A significant release of radioactive material likely to require implementation of planned countermeasures.
* KYSHTYM, Soviet Union (now Russia), 1957 - Significant
release of radioactive material to the environment
from explosion of high activity waste tank
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LEVEL 5 - ACCIDENT WITH WIDER CONSEQUENSES:
A limited release of radioactive material likely to require implementation of some planned countermeasures and several deaths from radiation.
* THREE MILE ISLAND, USA, 1979 - Severe damage to reactor core. This event galvanized opposition to a growing anti-nuclear power movement in the United States. After this event, energy companies did not start the construction of any new reactors in the United States for over 30 years and stopped work on several reactors that were already under construction
* WINDSCALE PILE, UK, 1957 - A release of radioactive material following a fire in a reactor core
* GOIANIA, Brazil, 1987 - Four people died and six people
received high doses of radiation
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LEVEL 4 - ACCIDENT WITH LOCAL CONSEQUENCES:
A minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls and fuel melt or damage to fuel resulting in more than 0.1 percent release of core inventory and the release of significant quantities of radioactive material within an installation with a high probability of significant public exposure
* TOKAIMURA, Japan, 1999 - Fatal overexposures of workers
following a criticality event at a nuclear facility
* SAINT LAURENT DES EAUX, France, 1980 - Melting of onehannel of fuel in the reactor with no release outside the site
* FLEURUS, Belgium, 2006 - Severe health effects for worker at a commercial irradiation facility as a result of high doses of radiation