The results of measurements of raws and building materials in poland in the context ofthe indoor 222rn concentration limitation.

Legal regulations on the utilization of raws and materials assigned for construction are applied inPoland taking into account radiation protection. A qualification coefficient f2 = SRa, where SRa is the 226Ra concentration in the material expressed in Bq/kg, connected with the limitation of radium concentration in the product due to the emanation of 222Rn (in parallel with qualification coefficient f1 limiting whole-body exposure for gamma radiation) is used for the purpose of limitation of the 222Rn concentration in buildings assigned for permanent residence of people. This paper contains the results of investigations of raws and building materials stored in the database of the Central Laboratory for Radiological Protection (CLOR). The investigations were carried out in years 19801998 by the CLOR and the network of the certification laboratories existing in Poland.The average 226Ra concentration for 1947 samples of lightweight and aerated concrete amounts to73 Bq/kg (one sample exceeding the legal limit). The average concentration of 226Ra for 3149 samplesof building ceramics (bricks, roof tiles, shapes) is 54 Bq/kg (again one sample not complying withlegal limits). Taking into account the raws of industrial origin, fly ashes are most commonly used as addition tobuilding materials. The average concentration of 226Ra for 7215 of such samples is 112 Bq/kg (about15% of samples did not meet the legal criterion).