Chernobyl

    A reactor at a nuclear power plant in Chernobyl, Ukraine exploded on April 26, 1986. According to a report carried out by the BBC, the explosion released at least 100 times more radiation than the atomic bombs detonated in Hiroshima and Nagasaki in 1945.

    On 25 April, prior to a routine shutdown, the reactor crew at Chernobyl 4 began preparing for a turbine test, but the power from  the turbine ran down too rapidly, so new voltage regulator designs were to be tested. A series of operator actions, including the disabling of automatic shut down mechanism, preceded the attempted test early on 26 April. By the time that the operator moved to shut down the reactor because it was in extremely unstable condition. The steam generator then exploded and released fission products to the atmosphere. About two or three seconds later, a second explosion threw a fragments from the fuel channels and hot graphite.

    Two workers died as a result of these explotions. The graphite and fuel became incandescent and started a number of fires, causing the main release of radioactivity into the environment. A large amount of radioactivity was released, over half of it being from biologically-inert noble gases. Two individuals died on the day of the explosion, followed by an additional 29 deaths due to radiation in the weeks following the accident.

    However, to this day the long-term effects of the explosion in the form of cancers and physical and mental deformities resulting from radiation exposure are still being accounted for.

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