title: Online measurement of unattached and total radon and thoron decay products.
abstract: Radon and thoron decay products appear in two size modes: unattached and attached to aerosol particles. They deposit at different regions of the human respiratory tract causing different inhalation doses. A separate measurement of the concentration of both modes is realized by a new device based on a working level monitor and screen sampling. In addition, a new operation and evaluation procedure of the working level monitor is described to identify the thoron decay products (212)Pb and (212)Bi separately. First measurements reveal consistent results. The developments in measurement technique will enhance radon and thoron dose assessment.
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany. oliver.meisenberg@helmholtz-muenchen.de
authors.forename: Oliver
authors.initials: O
authors.lastname: Meisenberg
authors.forename: Jochen
authors.initials: J
authors.lastname: Tschiersch
mesh_terms: D000336:Aerosols / Q000032:analysis; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis*; D009862:Online Systems; D011829:Radiation Dosage; D011886:Radon / Q000032:analysis*; D012137:Respiratory System / Q000737:chemistry
chemical_list: D000336:Aerosols; D011886:Radon