Above: bGeigie Nano in front of the Czech team’s Mi-17 helicopter
Note: Safecast is fortunate to have a small group of very active volunteers in the Czech Republic. The Safecast radiation map has a lot of data from the Czech Republic, almost all of it logged by Jan Helebrant and Lubomír Gryc, radioprotection professionals who work at the Czech National Radiation Protection Institute (Statni ustav radiacni ochrany, aka SURO). They told us about the great success they had a deploying a bGeigie Nano at a high-level international radiation survey exercise called the International Aero-Gammaspectrometry Campaign 2015, held in Germany last summer. We invited them to write a guest blog post about it.
By Lubomír Gryc and Jan Helebrant
National Radiation Protection Institute (Statni ustav radiacni ochrany, aka SURO, Czech Republic)
We recently participated in the International Aero-Gammaspectrometry Campaign 2015, in Germany. The official press release reads:
“European teams will be practising in Saxony and Thuringia
From 15 to 18 June, measurement experts from different countries will use helicopters to determine the radioactivity at ground level in parts of Saxony, Thuringia and the Czech Republic. These measurement flights are part of an international exercise hosted by the Federal Office for Radiation Protection (BfS) and the Flight Service of the German Federal Police (BPOLFLD), in close cooperation with the Czech Institute for Radiation Protection (SURO) and the Czech Army.”
The aim of the exercise was described as following:
“The use of helicopters and sensitive measuring devices makes it possible to identify radioactive substances on the ground rapidly and over large areas – without the need to enter these areas on ground level. This ability can be of utmost importance for quickly obtaining an overview of the radiation exposure on the ground, in particular in the event of an accident at a nuclear power plant with release of radioactive substances. In such event the competent authorities need reliable measuring data in order to decide which measures need to be taken for the protection of the population.”
That is, the exercise was focused on gamma spectrometry monitoring with different systems, and also on comparing the results. In addition to our high-volume NaI(Tl) scintillation detector, we also had other detectors, like an HPGe for spectrometry, and Geiger-based ones including the bGeigie for additional dose rate measurements.
Our team from the National Radiation Protection Institute (Statni ustav radiacni ochrany, aka SURO), together with colleagues from the Czech Army, attended the exercise along with with 5 other teams:
- Commissariat a l’Energie Atomique – CEA (France)
- Institut de Radioprotection et de Surete Nucleaire – IRSN (France)
- Nationale Alarmzentrale – NAZ (Switzerland)
- Bundesamt fur Strahlenschutz – BfS, Bundespolizei-Flugdienst – BPOLFLD (Germany, two joint teams)
Photo: The Czech team’s Mi-17 helicopter taking off
The bGeigie Nano worked well on board the helicopter, and we had no big problems with the GPS; as a precaution, we always started it outside and waited for the GPS lock. We had some GPS dropouts with the bGeigie, but in fact the same thing happened with our other devices.
Photo: Onboard the Czech team’s helicopter. Lubomír Gryc is second from right (in a dark t-shirt), and the team’s Nano rests on a piece of equipment in front of him.
Photo: Screenshot from GermanMDR TV news showing the bGeigie Nano inside the Czech team’s helicopter
The following map shows data measured with our bGeigie by helicopter in the Schneeberg area, well known for uranium mining. The mining heaps have been undergoing massive remediation during recent years, but it is still possible to detect slightly higher dose rates there. (More information about uranium mining in this area can be found here, here, and here).
Image: bGeigie data logged by helicopter in the Schneeberg area of Germany. (Note: Like other data logged from the air, this data has not been included on the Safecast radiation map)
However, as the flight height was variable – approximately 100 ±20 meters above ground – it would be quite complicated to recalculate the measured dose rates for the standard height of 1 meter above ground. The line spacing was about 1000 meters.
The maximum measured dose rate was 0.21 microSv/h with a median of 0.11 microSv/h. The truth is that the bGeigie, as well as most handheld radiation detectors, is simply not sensitive enough for measuring at such heights during normal situations. However our experiment at this exercise makes us think it could actually be useful during emergency situations where much higher dose rate levels are present, or for use with UAVs flying at much lower altitudes.
Photo: The former uranium mine at Schneeburg.