Nuclear power plant accidents: listed and ranked since 1952

How many nuclear power plants have had accidents and incidents? Get the full list and find out how they’re ranked

By . March 18, 2011

Nuclear power plant accidents: Number three reactor of the Fukushima nuclear plant is seen burning after a blast following an earthquake and tsunami Photograph: Ho/DigitalGlobe


How often do nuclear power plants go wrong? How many accidents and incidents are there?

The explosions and nuclear fuel rods melting at Japan‘s Fukushima nuclear power plant, following the Sendai earthquake and tsunami last week, have caused fears of what will happen next. Today Japan’s nuclear safety agency has raised the nuclear alert level for Japan from four to five – making it two levels lower than the Chernobyl disaster in 1986.

So far, the Japanese authorities have maintained that there is “no cause to fear a major nuclear accident”.

We have identified 33 serious incidents and accidents at nuclear power stations since the first recorded one in 1952 at Chalk River in Ontario, Canada.

The information is partially from the International Atomic Energy Authority – which, astonishingly, fails to keep a complete historical database – and partially from reports. Of those we have identified, six happened in the US and five in Japan. The UK and Russia have had three apiece.

Using Google Fusion tables, we’ve put these on a map, so you can see how they’re spread around the globe:

Get the fullscreen version


But how serious are they? The International Atomic Energy Authority ranks them using a special International Nuclear Events Scale (INES) – ranging from ‘anomaly’ to ‘major accident’, numbered from 1 to 7.

The events at Fukushima are level 5, so far and there has only been one 7 in history: Chernobyl in 1986. You can see the full ranking system below and on the attached spreadsheet

What can you do with the data?

Data summary

Year Incident INES level/th> Country/th> IAEA description
2011Fukushima5JapanReactor shutdown after the 2011 Sendai earthquake and tsunami; failure of emergency cooling caused an explosion
2011OnagawaJapanReactor shutdown after the 2011 Sendai earthquake and tsunami caused a fire
2006Fleurus4BelgiumSevere health effects for a worker at a commercial irradiation facility as a result of high doses of radiation
2006Forsmark2SwedenDegraded safety functions for common cause failure in the emergency power supply system at nuclear power plant
2006ErwinUSThirty-five litres of a highly enriched uranium solution leaked during transfer
2005Sellafield3UKRelease of large quantity of radioactive material, contained within the installation
2005Atucha2ArgentinaOverexposure of a worker at a power reactor exceeding the annual limit
2005BraidwoodUSNuclear material leak
2003Paks3HungaryPartially spent fuel rods undergoing cleaning in a tank of heavy water ruptured and spilled fuel pellets
1999Tokaimura4JapanFatal overexposures of workers following a criticality event at a nuclear facility
1999Yanangio3PeruIncident with radiography source resulting in severe radiation burns
1999Ikitelli3TurkeyLoss of a highly radioactive Co-60 source
1999Ishikawa2JapanControl rod malfunction
1993Tomsk4RussiaPressure buildup led to an explosive mechanical failure
1993Cadarache2FranceSpread of contamination to an area not expected by design
1989Vandellos3SpainNear accident caused by fire resulting in loss of safety systems at the nuclear power station
1989GreifswaldGermanyExcessive heating which damaged ten fuel rods
1986Chernobyl7Ukraine (USSR)Widespread health and environmental effects. External release of a significant fraction of reactor core inventory
1986Hamm-UentropGermanySpherical fuel pebble became lodged in the pipe used to deliver fuel elements to the reactor
1981Tsuraga2JapanMore than 100 workers were exposed to doses of up to 155 millirem per day radiation
1980Saint Laurent des Eaux4FranceMelting of one channel of fuel in the reactor with no release outside the site
1979Three Mile Island5USSevere damage to the reactor core
1977Jaslovské Bohunice4CzechoslovakiaDamaged fuel integrity, extensive corrosion damage of fuel cladding and release of radioactivity
1969LucensSwitzerlandTotal loss of coolant led to a power excursion and explosion of experimental reactor
1967ChapelcrossUKGraphite debris partially blocked a fuel channel causing a fuel element to melt and catch fire
1966MonroeUSSodium cooling system malfunction
1964CharlestownUSError by a worker at a United Nuclear Corporation fuel facility led to an accidental criticality
1959Santa Susana Field LaboratoryUSPartial core meltdown
1958Chalk RiverCanadaDue to inadequate cooling a damaged uranium fuel rod caught fire and was torn in two
1958Vin?aYugoslaviaDuring a subcritical counting experiment a power buildup went undetected – six scientists received high doses
1957Kyshtym6RussiaSignificant release of radioactive material to the environment from explosion of a high activity waste tank.
1957Windscale Pile5UKRelease of radioactive material to the environment following a fire in a reactor core
1952Chalk River5CanadaA 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



Original Source:

One Comment

    Join discussion: leave a comment