Indoor radon problem and ventilation strategies.

All buildings, depending on their design and particularly on how they are vented, are polluted to some extent with radon. Radon and its daughters may be trapped within buildings and accumulate there, thus threatening the health of their dwellers. Radon is an inert radioactive gas whose emanation into the building can mostly come from the underlying soil and from the building materials. The unhealthy buildings risk starts to act with tendency of saving energy and the related limitation of room ventilation to minimum. From indoor radon concentration point of view the dilemma does exist between air exchange respecting hygienic standards and indoor radon respecting limitation requirement of standard level. In this paper the seasonal and annual indoor radon concentrations related to ventilation rate in Slovak dwellings are presented. The study is based on continuous weekly radon measurements over a period of 1 year.