International monitoring networks

Within the European Union (EU), member states have committed to continuously monitor radioactivity in the environment. At the international level, the CTBT network for the monitoring of the Comprehensive Nuclear-Test-Ban Treaty provides data on radioactivity in the environment worldwide.

Monitoring networks at the European level

Member states of the European Union have committed to continuously monitor environmental radioactivity and operate networks similar to those established by the Federal Office for Radiation Protection (BfS). Austria and Switzerland have comparatively dense networks for monitoring the ambient gamma dose rate (ODL) similar to Germany; other countries focus on monitoring nuclear installations, and the monitoring stations are mainly located in proximity to these facilities.

The monitoring station on Mt Schauinsland is one of the four German locations of the sparse network for monitoring environmental radioactivity of the EU ("Dense and Sparse Network"). In accordance with Article 35 of the EURATOM Treaty, the data on ambient gamma dose rate (ODL) and activity concentrations in airborne dust recorded at the station are reported to the EU. Data of the local gamma dose rate (ODL) and other environmental media provided by the member states are summarised and published by the Joint Research Centre (JRC) of the EU.

The BfS collaborates with the JRC and is conducting a long-term inter-comparison experiment with radiation detectors from national and international monitoring networks within the project INTERCAL at Schauinsland monitoring station.

The worldwide monitoring network of the CTBT

The Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) operates a global monitoring network (International Monitoring System, IMS). The monitoring station on Mt Schauinsland is one of currently 73 certified stations able to detect aerosol-bound radioactivity at levels of a few microbecquerels per cubic metre of air. It is also one of only 25 certified stations worldwide able to detect radioactive xenon at levels below one millibecquerel per cubic metre of air.

The BfS has been supporting the CTBTO since the 1990s and has recently (2021/22) tested a new, state-of-the-art noble gas measurement system for the IMS at the Mt Schauinsland station. This new system is now certified and operates within the IMS.

The noble gas laboratory of the BfS in Freiburg is specialises in measuring radioactive krypton and radioactive xenon and measures long-term trends and short-term variability of their acitivity concentrations in air. Using backward atmospheric radioactivity transport modelling the BfS investigations potential sources and releases radioactivity. Over the past decades, samples from all continents including Antartica have been analysed.