Airborne concentrations and chemical considerations of radioactive ruthenium from an undeclared major nuclear release in 2017.

In October 2017, most European countries reported unique atmospheric detections of aerosol-bound radioruthenium (Ru). The range of concentrations varied from some tenths of µBq·m to more than 150 mBq·m The widespread detection at such considerable (yet innocuous) levels suggested a considerable release. To compare activity reports of airborne Ru with different sampling periods, concentrations were reconstructed based on the most probable plume presence duration at each location.

Potential Source Apportionment and Meteorological Conditions Involved in Airborne I Detections in January/February 2017 in Europe.

Traces of particulate radioactive iodine (I) were detected in the European atmosphere in January/February 2017. Concentrations of this nuclear fission product were very low, ranging 0.1 to 10 μBq m except at one location in western Russia where they reached up to several mBq m.

Analysis of radioxenon and Krypton-85 at the BfS noble gas laboratory.

Proportional counters and a β-γ coincidence system and their performance characteristics are described, with emphasis on internal and external quality controls. Typical limits of detection (LD) are 8mBqm for Kr and 4mBqm for Xe for the proportional counters, while for similar xenon volumes the LD for Xe in the β-γ system is approximately 4 times lower. Results of comparative analyses agree above the limit of quantification.

Tracking of airborne radionuclides from the damaged Fukushima Dai-ichi nuclear reactors by European networks.

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th.

Trace analysis of aerosol bound particulates and noble gases at the BfS in Germany.

The Federal Office for Radiation Protection (BfS) performs trace analysis measurements in both the frameworks of the German Integrated Measuring and Information system as well as of the International Monitoring System for verification of the Comprehensive Nuclear-Test-Ban Treaty. Therefore, different kinds of measurements of aerosol bound radionuclides as well as of radioactive noble gases in the atmosphere are performed. BfS as coordinating laboratory for trace analysis is responsible for the quality control.

An inter-laboratory comparison of low-level measurements in ground-level aerosol monitoring.

After the nuclear reactor accident of Chernobyl, the "Integrated Measurement and Information System (IMIS) for Monitoring the Environmental Radioactivity and Detecting Emissions from Nuclear Plants was implemented in Germany. IMIS is a nationwide comprehensive measuring system which permanently monitors the radioactivity in all important environment media in the whole federal territory. At approximately 40 sites, the activity concentration of radioactive substances is measured in air and precipitations.

Three years of operational experience from Schauinsland CTBT monitoring station.

Data from three years of operation of a low-level aerosol sampler and analyzer (RASA) at Schauinsland monitoring station are reported. The system is part of the International Monitoring System (IMS) for verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The fully automatic system is capable to measure aerosol borne gamma emitters with high sensitivity and routinely quantifies 7Be and 212Pb.

Monitoring ground-level air for trace analysis: methods and results.

Trace analysis enables the sensitive detection of radionuclide concentrations in ground-level air in the range of microbecquerel per cubic meter (microBq m(-3)). Typical sampling intervals of less than one day up to a few days can be used in routine operation. Trace analysis measurements are performed in the framework of the German Integrated Measuring and Information system (IMIS) and the International Monitoring System (IMS) used for verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT).