Validity of a single-sampler bronchial dosimeter for radon progeny

The validity of the single-sampler bronchial dosimeter for radon progeny (1-sampler configuration) proposed by Yu and Guan in 1998 (Health Physics, 75, 147–152) was checked using the results from the first-generation three-sampler bronchial dosimeter (3-sampler configuration) developed by Hopke et al. in 1990 (Health Physics, 58, 291–295), and Oberstedt and Vanmarcke in 1995 (Radiation Protection Dosimetry 59, 285–290). The basic difference between the two configurations was that the 1-sampler configuration required the assumption of activity median diameters (AMD) of attached radon progeny for different environments. In the present work, a method to determine the AMD from the results of the 3-sampler configuration was outlined. The dependence of the ratio (Γest/Γexp) on this determined AMD was then evaluated, where Γexp and Γest were the “experimentally determined” and the “estimated” deposition fractions of potential alpha energy concentration of radon progeny in the tracheobronchial region using the 1-sampler and 3-sampler configurations, respectively. The results showed that Γest/Γexp increased monotonically with the AMD, and was very close to unity when AMD was close to 150 nm, and the largest relative error introduced by using the 1-sampler configuration was around 25%, which was acceptable.