DETERMINATION OF PB-210 AND ITS PROGENIES IN AEROSOL FRACTIONS OF DIFFERENT PARTICLES SIZES

Determinations of Pb-210 in aerosol fractions of particle sizes betwee n 0.015-16 mu m have been carried out from air volumes of 35-100 m(3) by alpha-spectrometry via Po-210 after equilibrium has been establishe d, i.e. one or more years later, or directly by liquid scintillation s pectrometry using pulse shape analysis immediately after sample collec tion. In this way also the Bi-210/Pb-210 and the Po-210/Pb-210 ratios have been obtained. Based on different models published in the literat ure aerosol residence times are discussed.