Assessment of Radiation Dose Levels in Tiles Used for Decoration in Bungoma County, Kenya

The natural radioactive content of tiles used in Bungoma County, Kenya was assessed using gamma ray spectroscopy in this study. The amounts of certain radioisotopes found in 20 samples of decoration tiles used in Bungoma County, Kenya were estimated using a NaI(Tl) detector. The average activity concentrations of 226Ra, 232Th, and 40K for the tiles were determined to be 11±0.55, 109±5.85, and 1574±78.7Bq/kg respectively. Radiological hazard indices such as absorbed dose rate, radium equivalent activity, external Hazard Index (Hex), internal Hazard Index (Hin), Indoor and outdoor Annual Effective Dose (mSv/y), were determined as 140±7.03 nGyh-1; 288±14.44 Bq/kg, 0.7±0.03 mSv/y, 0.8±0.04 mSv/y; 0.5±0.02mSv/y; and 0.3±0.01mSv/yrespectively. The mean radium equivalent obtained in this investigation was lower than the worldwide reference value of 370 Bq/kg. Hence, use of tiles for decoration in Bungoma County, Kenya has minimal health threat to the population.