Application of scintillation counting using polycarbonates to radon measurements

This work proposes an approach for radon (222Rn) measurement based on scintillation counting of polycarbonate specimens. The proposed technique takes advantage of the high absorption ability of polycarbonates to 222Rn and of the fact that radiation emitted by 222Rn and its progeny causes the polycarbonate material to emit light. The theoretical background behind the proposed technique is presented and its application to two types of 222Rn measurements is demonstrated. The first application of the proposed technique is in the a posteriori calibration of compact discs for retrospective 222Rn measurements, where it is sometimes necessary to measure 222Rn concentrations higher than 2 MBq/m3 for several days. It is demonstrated that the application of the proposed technique increases the range of applicable 222Rn concentrations in the a posteriori calibration of CDs and adheres to its time and cost efficiency. The second application of the proposed technique is to soil-gas 222Rn measurements. The applicability of the technique is demonstrated in more than 110 radon-in-soil-gas measurements, which were performed in different terrains, covering 222Rn concentrations between 3 and 1200 kBq/m3. It is found that the measurements by scintillation counting of polycarbonates are consistent with the reference measurements by diffusion chambers with Kodak Pathe LR II detectors and very good linear correlations between the techniques are observed. The results from this study imply that the scintillation counting of polycarbonates may be suitable when fast, screening radon-in-soil gas measurements are necessary in a large number of points.