Bronchial dosimeter for radon progeny.

A true bronchial dosimeter has been designed, consisting of four 400-mesh wire screens and a filter paper. With a face velocity of 3.3 cm s(-1) for home exposure and 4.6 cm s(-1) for mine exposure, the deposition pattern on the wire screens were found to satisfactorily match the variation of the dose conversion factor (in units of mSv WL M(-1)) with the size of radon progeny from 1 to 1000 nm. In this way, the bronchial dosimeter directly gives bronchial dose from the alpha counts recorded on the wire-screens and the filter paper. Calculations of the dose conversion coefficient (DCC) using the proposed bronchial dosimeter and the lung dosimetric model were performed for typical aerosol characteristics. Values obtained from the bronchial dosimeter yielded overestimates of the DCC by 11.1% and 2.4% for typical home and mine conditions, respectively.