Influence of thermal comfort and building materials on indoor radon air concentration in some regions from Transylvania (Romania).

The purpose of this work is to see the influence of the heat preservation in the cold season and also to show the building material influence on the indoor radon concentration in dwellings. Three methods were used to measure the radon content in houses and buildings (workplaces). The results of measurements show that in the winter season the indoor radon concentration is about 2 times higher than in the summer season for these regions from Transylvania. This fact is due that in the cold season there is an evident tendency to preserve the heat, that is, the natural ventilation is very feebly. The influence of building materials on indoor radon concentration is clear shown in the fourth region namely Stei which is a region in the neighborhood of an uranium mine and in some of these houses uranium wastes were used as building materials.