Measurements of Dose Rate and Radon Gas Concentration in Schools and Kindergartens Constructed with Using Coal-slag As

Coals mined in some regions of the Transdanubian Middle Mountains in Hungary have elevated concentrations of Ra. The slags and ashes derived from these coals have been used as building material for schools and kindergartens. As the Ra reached up in these waste products of coal-firing systems, the gamma dose contribution in the buildings, which contained them, was calculated. In these places the absorbed gamma dose rate could be reach the sevenfold of the global average values – 80 nGy hbut the annual effective doses are lower than 1 mSv due to the relatively short time of occupancy even in the cases of highest level. The radon levels do not exceed the 102 Bq m during the period when the people are in the rooms because of the frequent airing therefore, the assumed annual effective dose derived from radon not exceed 0.4 mSv.