Deposition rates of Rn progeny in houses.
Deposition rates and velocities of indoor Rn progeny for both attached and unattached species are estimated from simultaneous measurements performed in 20 houses during 12 months. Fitting the values of working level ratio (the "equilibrium fraction"), the ratio between track densities of filtered and bare nuclear track detectors, section the air exchange rate, and the concentration of condensation nuclei to a theoretical model enabled us to calculate the average deposition rates for the houses in the study. This approach avoids the need to measure deposition rates on different types of surfaces in a house, and yields average values for houses with similar features (e.g. room sizes, heating, and air conditioning). Deposition rates were found to lie within about a factor of two of the average during the year, and exhibit higher values in the winter and lower values in the summer. Average deposition rates for the houses in the study were calculated to be 8 hr-1 and 1 hr-1 for unattached and attached radon daughters, respectively. These values correspond to deposition velocities of about 0.1 cm/sec and 0.015 cm/sec.
D001729:Bismuth / Q000032:analysis*; D006798:Housing; D007854:Lead / Q000032:analysis*; D011059:Polonium / Q000032:analysis*; D017687:Radon Daughters
D017687:Radon Daughters; D007854:Lead; D011059:Polonium; D001729:Bismuth