Radon and gamma-radiation measurements in schools on the territory of the abandoned uranium mine 'Zirovski vrh'

On the territory of the abandoned uranium mine 'Zirovski vrh', Slovenia, indoor radon and gamma dose rate measurements were carried out in nineteen schools from February 10 to May 10, 1995, using scintillation cells and etched track detectors for radon and thermoluminescence dosimeters for gamma-ray detection. In five schools indoor radon levels exceed 400 Bq x m-3, which is the proposed Slovene action level. The maximum average radon value of 1600 Bq x m-3 and the maximum gamma-dose rate of 172 μSv x month-1 were found in the same school. According to the ICRP 65 methodology, annual effective doses from radon decay products ranged from 0.05 to 6.10 mSv for pupils and from 0.04 to 4.90 mSv for teachers. Gamma dose rates ranged from 0.05 to 0.19 mSv x y-1 for pupils and from 0.07 to 0.27 mSv x y-1 for teachers. (author)