MEASUREMENT OF 222 Rn BY ABSORPTION IN POLYCARBONATES – RESEARCH AND PRACTICE

In the last few years, we have gathered experience in measurement of 222 Rn in air, water and soil-gas by absorption in polycarbonates. The method employs the remarkable absorption ability to noble gases of some polycarbonates, like Makrolon ® (the basic constructive material of CDs/DVDs). This report summarizes the key results of research and practical applications of this method. Calibration procedures, including a posteriori calibration, are described. Comparison between retrospective measurements (by CDs) and estimates based on conventional prospective 222 Rn measurements in dwellings are shown. The method is also used for measurement of 222 Rn in water and soil-gas. Comparisons with conventional methods for 222 Rn measurement in air, water and soil-gas are made and a good agreement is obtained. The sensitivity of the method covers the whole range of concentrations that are of practical interest. The potential for wide scale practical applications of this method and possible directions for further progress are discussed.