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Ionising radiation

Environmental Radioactivity - Medicine - Occupational Radiation Protection - Nuclear Hazards Defence

Ionisierende Strahlung

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.

Handheld measuring device used to determine the ambient dose rate in front of the Chernobyl reactor. The display shows a value of 3.04 microsievert per hour.

The Chernobyl accident

The accident occured in unit 4 of the Chernobyl nuclear power plant - a reactor type of Soviet design. The reactor was in the phase of slow shutdown. At the same time an experiment was planned for checking various safety features. Basic design failures of the plant in combination with failures and offences in operational management led to the reactor desaster.

Rethinking after Chernobyl and Fukushima

On the occasion of the commemoration ceremony "Chernobyl as a European challenge" for the 25th anniversary on 26 April 2011, Wolfram König, president of the Federal Office for Radiation Protection from 1999 to 2017, gave a speech on the reactor accident in Chernobyl in the French Friedrichstadtkirche church on Gendarmenmarkt, Berlin. This article contains a translation of Mr König's speech.

Units 1 to 5 in Fukushima Daiichi are designed with a Mark I-Containment

The Fukushima accident

After a large earthquake followed by a tsunami caused serious damage of the nuclear power plant Fukushima Daiichi in Japan. As a result radioactive substances were released.

Here you can find information about the sequence of the accident as well as the taken and planned countermeasures.

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