Radon transport phenomena studied in Karst caves-international experiences on radon levels and exposures

The results of radon measurements in caves obtained by using of nuclear track detectors are summarized. Mean radon concentrations are ranging worldwide from 0.1 to 20 kBqm −3 with 2.8 kBqm −3 arithmetic average. From long-term extended radon measurements in caves not only a detailed dosimetric picture can be drawn, but using radon gas as a radioactive tracer, the subsurface and near-to-surface transport processes can be studied, too. It will be shown that long-term radon monitoring by nuclear track detectors, in conjunctions with active detectors which enables detection of fast dynamic changes, offers very important information for naturally-occurring transport processes.