The following table compares the nuclear accidents at Fukushima Daiichi (2011) and Chernobyl (1986) nuclear power plants.
| Fukushima Daiichi | Chernobyl | |
|---|---|---|
| Location | Japan | Ukraine (ex. Soviet Union) |
| Date of the accident | March 11, 2011 | April 26, 1986 |
| Plant commissioning date | 1971 | 1977 |
| Years of operation before the accident | 40 years | 9 years |
| Electrical output | 4.7 Gigawatts | 1 Gigawatt |
| Type of reactor | Boiling water with containment vessel | Graphite moderated without containment |
| Number of reactors | 6 — 4 (and spent-fuel pools) involved in accident | 4 — 1 involved in accident |
| Amount of nuclear fuel in reactors | 1,600 tons | 180 tons |
| Cause of the accident | Shut down of cooling system due to tsunami | Accidental failure during safety feature experiment |
| Maximum level of radiation detected | 800 mSv | 200,000 mSv |
| Radiation released | 370 PBq (as of 12 April 2011) | 5,200 PBq |
| Area affected | Radiation levels exceeding annual limits seen over 60 kilometres (37 mi) to northwest and 40 kilometres (25 mi) to south-southwest, according to officials. | An area up to 500 kilometres (310 mi) away contaminated, according to the United Nations. |
| Exclusion Zone Area | 20 km (30 km voluntary) | 30 km |
| Population relocated | 300,000 | About 115,000 from areas surrounding the reactor in 1986; about 220,000 people from Belarus, the Russian Federation and Ukraine after 1986 |
| Direct casualties from the accident | none | 31 (64 confirmed deaths from radiation as of 2008, according to the UN) |
| Current status | Cold shutdown declared on 16 December 2011, but decommisioning will take 30-40 years. Radiation leaks drop and final outcome of the accident is due, according to officials. | All reactors were shut down by 2000. The damaged reactor is encased in concrete. A New Safe Confinement structure is expected to be completed in 2013. |
Last update December 17, 2011 (reference from BBC News).