Measurement of Gamma-Dose Caused by Built in Coal Slags with Elevated 226Ra Concentration, and the Modelling of Shielding

Slags, derived from coal mined in the neighbourhood of the town Tatabanya in Hungary, have been used as filling and insulating material for buildings of houses, block of flats, schools and kindergartens. The slag samples come from here have elevated concentrations of 226Ra, (range of 850–2400 Bq·kg−1). Therefore, the external gamma dose rates at 1 m height were about four times higher than the world average. It has been found, based on the modelling, that the dose rate could be decreased with 70–80% using an appropriate thickness of concrete or barite-concrete layers.