Assessment of Outdoor Radiation Hazard of Natural Radionuclides in Tourism Beach Areas
Ahmad Saat#1, Zaini Hamzah*2, Hamimah Jamaluddin*, Husna Mardhiah Muda*
#International Education College (INTEC), Universiti Teknologi MARA,
Section 17 Campus, 40200 Shah Alam, Malaysia.
#Institute of Science,
*Faculty of Applied Sciences,
Universiti Teknologi MARA, 40450 Shah Alam, Malaysia
Abstract— Tourism beaches are main attractions visited by members of the public for leisure and holidays. Knowledge of radiation hazard would enable the radiation risk estimation to be made, and suggest mitigation steps if needed. Surface radiation dose, activity concentration of 238U, 232Th and 40K, and radiation hazard index in 18 beaches at eastern, south western and southern coast of Peninsular Malaysia were determined. In-situ surface radiation dose measurements were done using portable radiation survey meter, while gamma-ray activities of sand samples were measured by using gamma-ray spectrometry method. The surface dose rates were found to range between 0.04 to 0.12 mSv hr-1. Mean activity concentration of 238U varies between 7.33 to 51.04 Bqkg-1, 232Th between 5.86 and 58.39 Bqkg-1 while 40K between 32.70 and 1292.9 Bqkg-1 respectively. The corresponding annual effective dose from these natural radiations ranged between 0.014 and 0.301 mSv/y. This average is way below the average worldwide exposure of 2.4 mSv/y. The external radiation hazard index calculated for the eighteen samples ranged between 0.05 and 0.51. No correlation was observed between in-situ dose measurement with the annual effective dose as well as radiation hazard index.
Keywords— Gamma-rays, annual effective dose, hazard index.