DOSE CONTRIBUTION FROM SCHOOL BUILDINGS CONTAINING COAL SLAG INSULATION WITH ELEVATED CONCENTRATIONS OF NATURAL RADIONUCLIDES

Coals mined in some regions of the Transdanubian Middle Mountains in Hungary have elevated concentrations of natural radionuclides as238U,226Ra, etc. Therefore, coal slags and ashes used for insulation of the school buildings may lead to high dose contributions on the students. In the city of Tatabanya one school was found where the external dose rates in the classrooms were of 500–900 nGy/h. In spite of the high external dose rates, the radon concentrations measured were small usually less than 100 Bq/m3.