Factors Affecting Indoor Radon Variations: A Case Study in Schools of Eastern Macedonia

The subject of this study is the radon concentrations variations, measured with a nuclear track detectors in a total of 58 premises in all 29 primary schools of 4 municipalities in the eastern part of the Republic of Macedonia. Despite a relatively small territory, the variability of radon concentrations proved to be significant. The geometric means (geometric standard deviations) of radon concentrations in the examined municipalities were in the range from GM=71 Bq/m3 (GSD=2.08) to GM=162 Bq/m3 (GSD=2.69), while for the entire region it was: GM=96 Bq/m3 (GSD=2.47). The influence of the geographical and geological features of the school site as well as the building characteristics on the radon variations were investigated. The analysis showed that type of municipality, building materials, basement and geology have significant effects and respectively describe 6\%, 16\%, 22\%, 39\% of the radon total variability