Trends en reductiescenario's voor Rn-222-concentraties in Woningen

Abstract

In the framework of the Dutch ministerial research programme Stratego (Radiation in buildings) there was a need for information on the consequences of possible measures to be taken to reduce the average radon (Rn-222) concentration in dwellings in the Netherlands. This study was devoted to that question starting of from the trends in building methods and use of building materials and using these trends as a reference development. The trend defined as the development without taking measures directed at reducing the radon concentration, predicts a slow increase of about 15% until approximately the year 2025. The scenario that is directed at using concrete with low Ra-226 concentrations in new houses almost stops this trend. A reduction of the average radon concentration in dwellings with 25% by the year 2025, compared to 1990, might be possible if measures, directed at decreasing the infiltration from the crawlspace to the house, in existing as well as in new buildings are applied. The effective dose-equivalent due to inhalation of radon-daughters and external exposure to them from building materials would then be reduced from the present 1,9 mSv.a-1 to 1,4 mSv.a-1. These reduction percentages have to be handled with some care however, because the effect of the obviously occurring uncertainties in several parameters used, are not yet quite clear.