Abstract
A survey concerning measurement of the indoor radon levels has been carried out in 105 workplaces of the Rawalpindi region and Islamabad Capital Territory using CR-39 based radon detectors. The main objective of this study was to assess the health hazard due to the indoor radon. CR-39 based NRPB type detectors were installed in offices/rooms located on first floors, ground floors and basements and were exposed to indoor radon for six months, The measured indoor radon concentration in the buildings surveyed ranged from 12 +/- 5 to 293 +/- 19 Bq m(-3) with an overall mean value of 64 +/- 32 Bq m(-3). The highest mean radon concentration (113 +/- 48 Bq m(-3)) was observed in the offices located in basements of the Rawalpindi city. The overall average annual effective dose in the studied workplaces was estimated to be 0.61 +/- 0.30 mSv. The mean annual effective doses in basements, ground floor and first floor were found to be 0.87 +/- 0.34 mSv, 0.55 +/- 0.28 mSv, and 0.47 +/- 0.29 mSv, respectively. These values are less than the action level recommended by International Commission on Radiological Protection. (C) 2009 Elsevier Ltd. All rights reserved.