Indoor Radon Concentrations and Effective Dose Estimation in Dwellings of As-Salt Region in Jordan

Abstract

Radon concentrations were measured using passive dosimeters, SSNTD CR-39 in As-Salt city and its surrounding. 300 dosimeters were distributed over the study area dwellings according to the fraction of the population. The exposure time started from April 2004 and lasted for 100 days. Radon concentrations were found to vary from region to region, ranging from 31 to 501 Bq m^-3 with a mean value of 111 ± 4 Bq m^-3. The concentration of radon short-lived daughters was estimated at 44 ± 2 Bq m-3or around 0.012 Working Level (WL). The ground floors were found to have the highest radon concentrations with a mean value of 118 Bq m^-3 , while the upper floors were found to have a mean value of 96 Bq m-3. Based on the use of the room, bedrooms were found to have a higher mean radon concentration than living or setting rooms; these concentrations were 117 ± 16 and 105 ± 5 Bq m^-3, respectively. It was found that As-Salt dweller is exposed annually to 0.49 Working Level Month (WLM) from radon gas and its short-lived daughters. Hence, a person takes on the average anannual effective dose equivalent to 2.7 mSv according to UNSCEAR and 1.9 mSv according to ICRP. This implies an expected value for lung cancer probability of 0.004%.

Keywords:Indoor radon concentration; Passive dosimeter; CR-39; Effective dose; Jordan.