Radon levels in karst caves in Slovenia

Abstract

A review is given on the radon survey in the Slovenian karst caves, those open for tourists and those for cavers and speleologists only. Radon concentrations differed markedly from cave to cave, as well as from point to point in the same cave. In addition to radon, in the Postojna Cave also radon decay products (RnDP), equilibrium factor between radon and RnDP, and the unattached fraction of RnDP have been monitored. Based on high radon levels, permanent radon monitoring was introduced in Postojna Cave and time spent by workers in the cave limited in order to keep their exposure to radon acceptably low.