Measure of exposure of short-lived radon products using an alpha spectrometer for measuring indoor aerosol activity concentration and dose evaluation

A new italian law introduces the regulation of occupational exposure to radon. To evaluate the inhalation of radon daughters by the workers a sampling device has been assembled with the aim of evaluation of unattached and aerosol attached radon daughters' fractions. The instrument, based on selection of the aerosuspended particles by means of a wire screen type battery and subsequent collection on a total filter, allows to describe the behaviour of both fractions using defined temporal pattern of collecting particles and counting them by alpha spectroscopy. A measurement campaign to test the radon daughter dichotomous spectrometer in comparison with a commercial Radon Working Level meter, has been performed in a research laboratory of central Italy affected by high radon concentrations. The radon concentration during the measurement campaign has been also measured. The equilibrium factor Feq ad the attachment factor fp have been evaluated during 3 days campaign. Using the measured mean parameters (radon concentration, Feq, fp) the dose evaluation for workers using dosimetric approach has been performed. A comparison between the epidemiologic approach, based on the radon concentration, and dosimetric approach is also presented