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FACTORS AFFECTING INDOOR RADON CONCENTRATIONS IN GREECE

A. Louizi, D. Nikolopoulos, H. Lobotessi and C. Proukakis
Medical Physics Department, Medical School, University of Athens
75 Micras Asias Street, Goudi, 115 27, Athens, Greece. Tel. (Fax): ++301-7793273

Indoor radon concentrations were determined with the use of track-etched detectors and two monitors,
both for radon and one for the decay products, in various regions of Greece. Until now, 1137
dwellings have been measured. Some factors, that influence the radon concentration in dwellings, are
discussed in this paper. The factors, used in this analysis, were derived from the householders’
answers to the relevant questions about various physical features of the dwelling.
Different statistical methods were used, as the unpaired t-test and the ANOVA method. The ANOVA
method was used on the set of 945 dwellings with complete radon measurements and questionnaires.
The factors, which have been studied are the height of the dwelling from the ground, the position of
the detector in the room, the building materials, as well as the type of the building, the floor, the
basement, the construction period, the contact with other buildings and the mechanical ventilation.
It was found that only the height of the dwelling and the building materials affect radon
concentrations. The soil was not included as a factor, due to lack of soil data for the total number of
945 dwellings. Only, in a subgroup of 120 dwellings in selected areas in Greece, we checked any
possible correlation between indoor radon concentration and radium content of the substrate soil, but
the linear correlation coefficient was very low.
Key words: 222 Rn, indoor, concentration, building materials, soil, survey