Radon Levels in Dwellings of New Mirpur Azad Kashmir, Sub-Himalayas, Pakistan

Radon concentrations were measured in kucha, semi-kucha and pucka houses located on the sedimentary rocks of Early Pleistocene-Pliocene Soan Formation, Pleistocene Mirpur conglomerate and recent deposits. The radon concentration was measured using CN 85 nuclear tracks etch detectors in box type dosimeters installed in the bedrooms and kitchens of the houses. It was found to vary from 14 ± 7 Bqm -3 to 258 ± 28 Bqm -3 with an average of 105 ± 17 Bqm -3 . The average radon concentration in the kucha, semi-kucha and pucka houses was 78 ± 15 Bqm -3 , 108 ± 18 Bqm -3 and 108± 18 Bqm -3 respectively. The increase in radon concentration from kucha to pucka houses was attributed to the type of house, differing humidity related to the Mangla Dam, temperature, bed rock geology, structures (joints, fractures and faults), aggregates and uranium-bearing sand. This study shows that the average radon level is within the accepted safe health limit (200 Bqm -3 ) for the inhabitants of New Mirpur Azad Kashmir, Pakistan.