Helicopter exercise: Federal Office for Radiation Protection and German Federal Police Air Service measure radioactivity from the air

From 8 to 10 October 2013, the Federal Office for Radiation Protection (BfS) and the German Federal Police Air Service (BPOLFLD) will train environmental radioactivity measurements from a helicopter in a joint exercise in Rhineland Palatinate, Hesse and Saarland. The exercise is a precautionary measure: With such measures, the Federal Office for Radiation Protection and the German Federal Police Air Service can determine the distribution of radioactive material in the environment quickly and over large areas in case of emergency. That may become necessary, for example, if radioactive material is released in case of an accident in a nuclear power plant.

Objective of the exercise

The annual measurement exercises serve to optimise the measuring and evaluation techniques and to check their functionality. Besides, the co-operation of the Federal Police emergency services and the scientific-technical staff of the Federal Office for Radiation Protection is trained and improved. A special feature of this year’s exercise is the BfS' deployment of measuring teams on the ground. They measure the radioactivity from vehicles and take soil samples for later analysis in the laboratory.

In the follow-up to the exercise, the obtained data is made available to the competent authorities in Rhineland Palatinate, Hesse and Saarland. The areas where the exercise takes place is agreed between the Federal Office for Radiation Protection and the respective federal states. Several areas near Schweisweiler, Schallodenbach and Ellweiler with natural uranium resources, the vicinity of the Biblis nuclear power plant and areas around Merzig and Trier bordering France and Luxembourg will be overflown. Here, the BfS already carried out measurements in the framework of a transnational emergency exercise for the Cattenom nuclear power plant. These measurements are now supplemented. In the past years, the vicinity of nuclear installations in Schleswig-Holstein, Lower Saxony and Baden-Wurttemberg was overflown in the framework of the BfS and BPOLFLD exercises.

The exercise

During the exercise, probably on 8 October from 10 a.m. to 5 p.m., test flights will be conducted near Speyer and the first measurement flights near Schweisweiler will take place. On 9 October, from 9.30 a.m. and 5 p.m., the areas around Ellweiler, Schallodenbach, Schweisweiler and Biblis are on the agenda. For the same time on 10 October, measurements around Merzig and Trier are scheduled. As the exercise depends on weather conditions, the planned order of the measuring flights may be subject to change on short notice. For measurement reasons, the flight altitude will be about 100 m in general.

For the exercise, two helicopters of the Federal Police will be equipped with special measuring devices for the detection of gamma radiation. In addition to the measurement results, the geographic co-ordinates will be recorded, so that the spatial distribution of the measured radioactive material can be presented in a graph once a measuring flight has concluded.

Air-borne radioactivity measurement

Air-borne radioactivity measurement, the so-called aero gamma spectrometry, makes it possible to detect radioactive sources and to measure quickly possible radioactive contamination of a large area. An area of 70 sqm can thus be examined within three hours. This helps support fast decisions about necessary emergency measures for the general public or justify the necessity of detailed examinations on the ground.

For the measurements from the vehicles on the ground the BfS uses measuring devices that work according to the same principle as the measuring devices in the helicopters. Thus, it is possible to compare the results directly. These measurements are supplemented by examination of the the soil samples in the laboratory.

Pursuant to the Precautionary Radiation Protection Act, the Federal Office for Radiation Protection is responsible for the quick air-borne radioactivity measurement of the ground surface over large areas. The Act was passed after the Chernobyl reactor accident, in order to keep the radiation exposure to the population as low as possible in case of incidents involving considerable radiological consequences. For the implementation of this task, the Federal Office therefore provides four measuring systems on the sites of Munich and Berlin, which can be installed in the Federal Police's helicopters and can then be taken to an area to be examined. Six BfS vehicles are available for supplementing measurements on the ground.