In-vivo measurement of deposition and absorption of unattached radon progeny

Publisher Summary Exposure to airborne radon progeny in the domestic environment yields the largest source of exposure to ionizing radiation of the general public. The radiation protection principle of overestimating the risk rather than underestimating it has limitations when applied to sources of natural radiation. As the exposure to radon progeny concerns the total population of a country, a consensus has to be found between the justified wish of the people for protection against health risks and the financial expenditure and administrative effort necessary for protective actions. The choice of an action level for radon exposure plays an important part in the decision for remedial actions against elevated radon concentrations. Scientific research has the assignment to supply the fundamental knowledge for this choice. The present results together with literature data on the absorption of aerosol attached radon progeny show that the unattached fraction is absorbed at a faster rate into blood than the attached radon progeny. This results in the equivalent dose to the lung for a typical home being reduced by about 15%.