Laboratory and field tests of a hassock fan-ion generator radon decay product removal unit

Laboratory tests in a radon chamber of a hassock fan-ion generator unit, developed for reducing airborne radon decay product concentrations inside buildings, produced reductions in potential alpha energy concentrations (PAECs) ranging from 83% to 86%. Similar reductions were observed in rooms in a home with relatively high radon concentrations. Reductions in a home with relatively low radon concentrations ranged from 76% to 79%. The time required for the removal unit to reach the point of maximum reduction was 6 to 8 h. A major share of the reduction occurred within the first 3 to 4 h. The speed of the fan, which was variable, had little effect on the ultimate removal efficiency. Reductions in the dose equivalent to the lungs, estimated on the basis of laboratory studies utilising several lung dosimetric models, were only slightly less than the observed reductions in PAECs. (author)