Concentrations and deposition rates of 220rn progeny in houses

A convenient, low-cost, time-integrating monitor based on the track-etching technique wasdeveloped for measuring the deposition rate of attached 220Rn progeny indoors. Simultaneousmeasurements for deposition rates and concentrations of 220Rn progeny were performed in 13 housesduring 12 months. Various values were observed among those houses, but seasonal variations werenot clearly observed. The deposition velocity of attached 220Rn progeny was estimated to be(0.53?0.11)?10-2 cm?s-1, in fair agreement with most of the values of attached 222Rn progeny indwellings in the literature. Significant correlation (r = 0.981) was found between the deposition ratesand concentrations of 220Rn progeny, and no significant variance of the deposition velocity forattached 220Rn progeny was found among those typical dwellings. It suggests that it is possible toevaluate indoor 220Rn progeny concentrations by simply measuring their deposition rates.