Evaluation of natural radioactivity in ceramic and porcelain samples using a high-purity germanium detector (HPGe)

Abstract

This study was conducted to determine the natural radioactivity concentrations of 30 different commercial samples of ceramic and porcelain tiles using gamma ray spectrometry with a high-purity germanium detector. The results of the study showed that the natural radioactivity concentrations of 226 Ra, 232 Th, and 40 K ranged from 34.181 Bq/kg to 143.49 Bq/kg, 25.132 Bq/kg to 93.426 Bq/kg, and 251.40 Bq/kg to 1283.74 Bq/kg, respectively. The radiation hazards resulting from natural radiation exposure of the samples were evaluated by calculating the radium equivalent, the airborne absorbed dose, the annual effective dose, and the outdoor and indoor hazard index. The radium-226 equivalent activity (Ra_eq) was calculated, and the calculated values were lower than the OECD recommended value of 370 Bq/kg. The results also showed that the absorbed dose rate values for all samples were higher than the internationally recommended value of 55 nGy/h. The annual effective dose rate values for all studied samples were lower than the recommended value of 1 (mSv)/y. The results showed that the external hazard index (H_ex) values were within the internationally recommended value, i.e., less than one, while the internal hazard index (H_in) values for a Saudi-made porcelain sample, as well as some ceramic samples imported from Algeria and Tunisia, were higher than one.