This paper presents the results of measurements related to the activity concentrations of 226Ra, 232Th and 40K in autoclaved
aerated concrete (AAC) used as building materials for various constructions in Romania. Radiation index (I) and the hazard index
(HI) were estimated to assess the risk arising from the usage of AAC materials. Our study considered various AAC samples
produced by different companies, in 2015. The activity concentrations of 226Ra, 232Th and 40K were measured using by a gammaray
spectrometer with HPGe detector. The average activity concentrations of 226Ra, 232Th and 40K were found to be 24.6, 15.7 and
respectively, 221.3 Bq/kg. The findings were compiled in accordance with the normative of national and international reference,
and showed a very good environmental behavior regarding the emission of radionuclides from the analyzed AAC samples. There
is no risk for human beings and the radiation index is under the regulations, even if the worst scenario is considered as reference
(<0.5), the hazard index (HI) being in all situations under the acceptable level.