The URDM is a semi-passive radon-daughter monitoring system that can be coupled with any medium constant-flow-rate air sampler. The URDM contains a glass-fibre filter and the nuclear-track detector film Kodak LR-115. When air is drawn through the filter, radon daughter products remain on the filter and the alpha particles they emit are detected by the nuclear-track detector film. The film is developed, the nuclear tracks are counted, and the potential alpha energy concentration (PAEC) of radon daughters is estimated by considering the total volume of air sampled and the track density.
The alpha-track-density-to-PAEC conversion factor is obtained through system calibration inside the South Australian EPA Radiation Protection Branch Radon Calibration Chamber.
Gallery
