Absorbed fraction and dose conversion coefficients of alpha particles for radon dosimetry

The sensitivity to different relevant parameters of the absorbed fraction o f alpha particles emitted from the Rn-222 chain in sensitive cells of the t racheo-bronchial tree have been investigated. The structure of the airway w all given by ICRP (ICRP66) has been adopted and employed in the present cal culations. The source thickness (mucous gel and sol + cilia), target layer thickness and the depth of the sensitive layers have been varied within rea sonable ranges around the default values recommended by ICRP66. The results have shown that the depth of the sensitive layers is the most important pa rameter in calculating the absorbed fraction. In addition, dose conversion coefficients were calculated and presented along with the absorbed fraction s.