Radon measurements in some houses of Tsukuba science city, Japan

Measurements concerning radon and its daughter products' concentration levels have been performed in 42 selective houses of the Tsukuba Science City (Japan) using CR-39 and LR-115 nuclear track detectors. These included both single story houses and flats in multi-storied buildings. Four CR-39 and four LR-115 detectors were put into a zippable polyethylene bag and a number of such bags were prepared. These detector loaded bags were then installed in two bedrooms of each of the houses/flats and were exposed for a period of three months during the winter season (i.e. from December to February). These radon exposed samples were then processed, analyzed and related to the Bq/m 3 . These studies indicated that the radon levels are very low in the houses surveyed and do not pose any serious threat to the occupants.