Abstract: Zircon is the mostly widely occurring zirconium-containing mineral mined commercially. Thorium and uranium may substitute for zirconium in the zircon crystal lattice. The radioactivity levels in zircon lies typically within the ranges 500-1000 Bq kg−1 for 232Th and 1000-5000 Bq kg−1 for 238U [1]. One of the most important use of zircon is as opacifier for ceramic tiles. Body of ceramic tiles is a mixture of different raw materials, including: clays, quartz materials and feldspathic materials. The body may be glazed or left unglazed. Due to the zircon in the glaze or in the body, ceramic tiles can show natural activity concentration significantly higher than the average values of Earth’s crust. This study contains a summary of results obtained by a survey on Italian ceramic tiles collected over three years (2005-2007). About one hundred of ceramic tiles were analysed. The survey consisted of measurement of 226Ra, 232Th and 40K activity concentrations and of the gamma-index [2] and radium-equivalent [3-4] calculation. The activity concentrations of 226Ra, 232Th and 40K result of the order of 100, 50 and 500 Bq kg−1, respectively. In all samples the activity concentration index has been found well below the acceptable limit.
S. Righi, A. Albertazzi, R.Guerra, M.Jeyapandian, S.Verità (2008). Natural radioactivity in Italian ceramic tiles. OSTERAS : Norwegian Radiation Protection Authority.
Natural radioactivity in Italian ceramic tiles
RIGHI, SERENA;GUERRA, ROBERTA;JEYAPANDIAN, MALATHI;VERITA', SIMONA
2008
Abstract
Abstract: Zircon is the mostly widely occurring zirconium-containing mineral mined commercially. Thorium and uranium may substitute for zirconium in the zircon crystal lattice. The radioactivity levels in zircon lies typically within the ranges 500-1000 Bq kg−1 for 232Th and 1000-5000 Bq kg−1 for 238U [1]. One of the most important use of zircon is as opacifier for ceramic tiles. Body of ceramic tiles is a mixture of different raw materials, including: clays, quartz materials and feldspathic materials. The body may be glazed or left unglazed. Due to the zircon in the glaze or in the body, ceramic tiles can show natural activity concentration significantly higher than the average values of Earth’s crust. This study contains a summary of results obtained by a survey on Italian ceramic tiles collected over three years (2005-2007). About one hundred of ceramic tiles were analysed. The survey consisted of measurement of 226Ra, 232Th and 40K activity concentrations and of the gamma-index [2] and radium-equivalent [3-4] calculation. The activity concentrations of 226Ra, 232Th and 40K result of the order of 100, 50 and 500 Bq kg−1, respectively. In all samples the activity concentration index has been found well below the acceptable limit.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
