Proficiency in monitoring radioactivity in air
JRC scientists organised an inter-laboratory comparison study to assess the measurement performance of EU monitoring laboratories. For this purpose, air filters were spiked with 137Cs. The results revealed that EU Member States improved their performance since the last exercise organised in 2003.
After the Chernobyl Nuclear Accident, several new regulations came into force, and the Member States of the European Union are requested to report radiological monitoring data of airborne radioactivity to the European Commission according to the Council Decision 87/600 and the Commission Recommendation 2000/473/Euratom. The JRC-Institute for Transuranium Elements (ITU) collates the measurement results in the European Union Radiological Data Exchange Platform (EURDEP). Currently, there are about 240 stations with sampling equipment for radioactive particulates in the air, using a wide variety of different methods, instruments and air filters. 137Cs is one of the most often monitored radionuclides in the air because of its relatively simple measurement method and presence in any nuclear event.
In support of the Euratom Treaty Articles 35/36 (monitoring and reporting of radioactivity in the environment), an inter-laboratory comparison study on low levels of radioactivity was organised by the JRC- Institute for Reference Materials and Measurements (IRMM). Participants in this study comprised 76 European environmental radioactivity monitoring laboratories. In providing air filters with activity levels similar to those which the laboratories routinely measure and to allow them to measure following their usual procedure and measurement geometry, the test sample was prepared individually for each participant by gravimetrically dispensing activity amounts on the surface of blank air filters supplied by the participants. JRC-IRMM provided the comparison samples with fully documented reference values. The aim of the present ILC was to obtain an overview of the quality and comparability of results provided by the participating laboratories and of any changes that have occurred since the last similar exercise of 2003.
The results provided by the participants demonstrated that almost all the laboratories could report a reliable measurement result, which is an excellent outcome and a marked improvement since 2003. On the other hand, it is worth mentioning that there is still room for improvement in the uncertainty estimation.