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Ionising radiation

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

Ionisierende Strahlung

Radon areas in Germany

  • The Radiation Protection Act obliges the federal states to indicate by the end of 2020 the areas where a high concentration of radon can be expected in buildings.
  • So that there is a sufficient data foundation, the federal states are carrying out measurement programmes before they can specify the areas.
  • Under the Radiation Protection Act, different regulations on protection from radon apply in these areas – this depends on whether the buildings are residential or workplaces.

The Radiation Protection Act obliges the federal states to indicate by the end of 2020 the areas where a high radon concentration can be expected in buildings. If radon accumulates in indoor spaces, it can cause lung cancer.

Creating a data foundation

So as to build a solid data foundation by the end of 2020, the federal states are already carrying out measurement programmes. The data will establish the areas in which a high radon concentration can be expected in buildings.

Basically, there are two ways of estimating where and in what quantities radon can occur in buildings:

  • possible radon concentrations in houses can be extrapolated from the radon incidence in soil air and the gas permeability of the soil or
  • the radon potential in the soil can be extrapolated from measurement values of radon concentration in indoor spaces. Either option requires a very large number of measurements.

BfS compiles forecast map of radon potential

On the basis of the measurement data gathered in the federal states, the Federal Office for Radiation Protection (BfS) will update the forecast map of radon potential. The radon potential indicates how strongly radon is seeping from the soil and can potentially penetrate into indoor spaces in houses. With this forecast, the BfS supports the federal states in indicating the areas where a high radon concentration can be expected in many buildings.

It is expected that these areas are mainly in the Mittelgebirge regions and the Alpine foothills as there are high proportions of uranium-rich rock in the soil there. Radon arises during the radioactive decay of uranium.

Regions in the Northern German lowlands could also be affected.

Special rules for protection from radon

In the areas where a high radon concentration is expected in many buildings, Radiation Protection Act stipulates different regulations for protection from radon – this depends on whether the buildings are residential or workplaces.

Under the Radiation Protection Act, a reference value provides a benchmark for the suitability of protection measures. If this is exceeded, lasting measures must be adopted to reduce the radon concentration.

State of 2018.11.21

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