Dose assessment due to radon exposure in some Egyptian dwellings using LR-115 nuclear track detectors

Indoor radon concentrations were measured in 180 dwellings across 15 selected cities in Egypt, using the cup technique with LR-115 nuclear track detectors in place over a one-year period. Radon activity concentrations ranged from 28 to 53 Bq m^-3, with an average value of 38 Bq m^-3. These values are below the threshold set by US-EPA (148 Bq m^-3), WHO (100 Bq m^-3) and ICRP (200-300 Bq m^-3). The indoor radon equilibrium factor (F) ranged from 0.31 to 0.41, averaging 0.37, close to the UNSCEAR recommended value of 0.40. The annual effective indoor dose to residents was estimated to range between 0.99 and 2.00 mSv, averaging 1.38 mSv, which is lower than both the global background level (1.1 mSvy^-1) and the ICRP's recommended action level (10 mSvy^-1). The mean excess lifetime cancer risk (ELCR) was estimated at 0.53 %. These findings suggest that radon levels in the surveyed dwellings pose no significant health risks to the occupants.