Working level measurement of radon and thoron daughters in the low atmospheres using a two-count method

Working level measurements of radon and thoron daughters in the low atmospheres using a two-count method. Working level measurements of radon and thoron daughter were performed in the Nuclear Physics Laboratory, Faculty of Mathematics and Natural Sciences, Gajah Mada University, Yogyakarta, using a two-count method which was developed by Erling Stranden (1979). These measurement were carried out by letting air to flow through a suction pump. Dust particles contained in the air will then be deposited on the fiber glass filter installed on the suction pump office. The count rate measurement of the dust particles were then carried out using a ZnS(Ag) scintillation detector. The results of the measurement show that the working level thoron daughters is of the same order of magnitude as the working level radon daughters, and that the magnitude of the working level of radon and thoron daughters is higher during the dry season than in the rainy season. (author). 6 refs., 3 tabs