Radon and thoron progeny measurements in dwellings of northern Greece

Radon progeny concentration is measured with a total alpha counting system in 185 dwellings in thetown of Thessaloniki. The Equilibrium Equivalent radon Concentration (EEC 222Rn) follows a lognormaldistribution with an arithmetic and geometric mean value of 28 Bq/m3 and 16 Bq/m3 respectively. Simultaneous in situ alpha and gamma spectroscopy measurements were performed in 60 schools of Thessaloniki. The mean equilibrium Equivalent Concentration of radon and thoron is 22 Bq/m3 and 0.9 Bq/m3 respectively.