RESUMO
The use of granite in buildings may constitute an additional source of radiation exposure to both workers and members of the public from gamma radiation produced by radioactive decay in the granite-sheet. The calculations presented in this paper indicated that if different types of granite sheets 2 cm thick containing a 226Ra eq concentration of 236.09889 Bq/kg for red granite and 360.92307 Bq/kg for rose granite are used in the walls and floor of a bank hall of dimensions up to 8 m x 10 m x 3 m and 10 m x 12 m x 3 m, the annual effective dose from gamma radiation for a worker or public person occupying the bank hall is lower than the maximum acceptable 226Ra concentration in building materials. The calculations presented in this paper are much more realistic in that they take the geometry of the building materials into account