Radon measurement studies in workplace buildings of the Rawalpindi region and Islamabad Capital area, Pakistan

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.