Study of radon exhalation rates using LR-115 (II) nuclear track detectors in coal-mining area of the foothills of Mokokchung District, Nagaland

The coal-mining area of the foothills of Mokokchung District, Nagaland bears significant geological features. Radon exhalation from ground plays an important role in enhanced indoor radon levels. Exhalation rates (mass and surface) from coal and soil samples of the area have been studied using LR-115 (II) nuclear track detectors. The mass and surface exhalation rates from coal samples varied in the range 9.7-16.2 mBq/kg/h and 323.5-538.6 mBq/m2/h, respectively. The mass and surface exhalation rates from soil samples varied in the range 11.1-15.2 mBq/kg/h and 368.3-507.6 mBq/m2/h, respectively. The study has revealed substantial presence of radionuclides in the coal and soil of the area. (author)