Application of a radon model to explain indoor radon levels in a Swedish house

Radon entry from soil into indoor air and its accumulation indoors depends on several parameters, the values of which normally depend on the specific characteristics of the site. The effect of a specific parameter is often di fficult to explain from the result of indoor radon measurements only. The a daptation of the RAGENA (RAdon Generation, ENtry and Accumulation indoors) model to a Swedish house to characterise indoor radon levels and the relati ve importance of the different radon sources and entry mechanisms is presen ted. The building is a single-zone house with a naturally-ventilated crawl space in one part and a concrete floor in another part, leading to differen t radon levels in the two parts of the building. The soil under the house i s moraine, which is relatively permeable to radon gas. The house is natural ly-ventilated. The mean indoor radon concentration values measured with nuc lear track detectors in the crawl-space and concrete parts of the house are respectively 75+/-30 and 200+/-80 Bq m(-3). Results of the model adaptatio n to the house indicate that soil constitutes the most relevant radon sourc e in both parts of the house. The radon concentration values predicted by t he model indoors fall into the same range as the experimental results.