Assessment of Indoor and Outdoor Radon Levels in South Lebanon

The presence of high indoor radon concentrations, Cx, is a major concern of the public worldwide. Measurements of indoor radon in South Lebanon have been achieved using CR-39 detectors. Cx values ranged between 30 and 122 Bq m−3 in one of the major towns in the area and are compared with measured atmospheric air Radon. Moderate seasonal variation of Cx indoors has been observed, although 90 % of the obtained indoor Cx measurements are below 100 Bq m−3. Some homes produced Cx readings above the permissible limit. Results showed that the ventilation effect played a major factor in reducing radon concentration levels indoors. Health assessment has been considered. Annual effective doses of radon varied from 1.01 ± 0.10 to 8.65 ± 0.50 mSv a−1 in six homes in one of the four cases studied. These dosage values are above the permitted limit of 2.5 mSv a−1. Several types of granite contained in the studied homes were identified and their contributions to radon levels indoors were calculated.