Title: Radiation doses due to the natural radioactivity in Pakistan marble
Abstract:In view of its high potential for containing large amounts of radioactive materials and due to its wide-spread use as construction and facing material worldwide, radiation doses received from the marb...In view of its high potential for containing large amounts of radioactive materials and due to its wide-spread use as construction and facing material worldwide, radiation doses received from the marble used in dwellings have been determined. As a first step, specific activity measurements were made using a NaI(Tl) gamma ray spectrometer using the spectrum stripping technique. For the samples studied, the average values of specific activities for 226Ra, 232Th and 40K have been found to be 27, 26 and 58 Bg kg-1 respectively. The mesh-adaptive, volume-integral method based code INGRE (Mirza et al., 1991) gave calculated values of the dose equivalent rates inside the standard room (Tufail et al., 1994) due to 226Ra, 232Th and 40K; these we re found to lie between 5-77, 12-52 and 1-11 nGy h-1 respectively. The values of whole-body dose equivalent rates have been found to lie in the 27-108 nGy h-1 range. As these values are below internationally accepted maximum permissible values, therefore marble available in Pakistan can safely be used in dwellings as a construction material.Read More