This paper briefly reports some data from investigations carried out in the Afra hot springs, 160 km south of Amman, Jordan. These data emphasise the new findings of high-radiation dose equivalents, mainly to identify the potential and known impacts of exposure on public health in High Levels of Natural Radiation Areas (HLNRAs) of this region, and also to make recommendations for further studies. A significant part of the total dose contribution in the form of natural sources comes from terrestrial gamma radionuclides. The measured absorbed dose rates in air were in the range of 10-18 000 nSv/h. The absorbed external dose rate of the high-radiation zone due to gamma radiation was measured to be 4.0 mSv/h, which is the highest registered dose rate anywhere in the world (Ajlouni et al., 2009). The absorbed external dose rate outside the high levels of natural radiation in the Afra hot springs areas is less than 10 nSv/h.
Keywords: Afra hot springs, natural radioactivity, dose equivalent, external gamma doses, NaI(Tl) detector, low radiation, Jordan, public health, radiation exposure, terrestrial gamma radionuclides