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Nuclear safety

Nuclear Facilities - Reportable Events - Decommissioning - Nuclear Accidents

nuclear safety

Nuclear accidents

In the history of the civil utilisation of nuclear energy there have also been accidents in nuclear facilities. The causes of the accidents have very much differed. Nuclear accidents can, for example, be caused by the failure of technical components, by human error or by natural disasters. As a result of a nuclear accident a significant level of radioactive substances is released. This can effect health and environment.

The most known nuclear accidents leading to massive releases of radioactive substances into the environment occurred in Chernobyl/Ukraine in 1986 and in Fukushima/Japan in 2011.

  • Arched protective shell over destroyed Chernobyl reactor from 2020Source: picture alliance / Photoshot

    The Chernobyl accident

    The accident occurred on 26 April 1986 in unit 4 of the Chernobyl nuclear power plant in Ukraine. Large quantities of radioactive material were released and spread across the northern hemisphere. Depending on the occurrence and intensity of the precipitation during the passage of the radioactive air masses, the radioactive contamination in the affected areas varied considerably. In order to reduce the release of further radioactive material after the accident, a protective cover was erected over the affected reactor block.

  • Three workers in protective clothing looking over the site of the Fukushima nuclear power plantSource: BASE / Michael Meier

    Fukushima: The catastrophic accident and its consequences

    On 11 March 2011 a strong earthquake and, following this, a tsunami occurred in Fukushima/Japan. Significant damage was done to the Fukushima Daiichi nuclear power plant, which was impossible to manage with the available safety and security systems. The radioactive substances released as a result of this accident have contaminated air, soil and water in the area around Fukushima. So far, it has not been possible to evaluate health effects finally.

© Federal Office for the Safety of Nuclear Waste Management