Simulation of the dose rate of building materials γ-radiation in the premises of different designs has revealed the minimal levels of human exposure. It was determined that the exposure dose rate at the given points of a single room depends on the content of natural radionuclides in construction materials and the changing geometry of a person's exposure in the premises. When the exposure dose rate of γ-radiation above an individual plate is determined, it is conventionally divided into the discrete sources, the dose rate from several plates is summed up. It is shown that near a vertical wall with a uniform content of natural radionuclides the exposure dose is higher where the wall is thicker. When radiation is emitted from the floor of a certain thickness, a maximum exposure dose rate occurs, which becomes greater when the layer of half attenuation of the material increases. The exposure dose rate also increases in the corners of the room: the higher the room the greater the dose rate. The results obtained predict the doses of human exposure at various points of the room, which determines the conditions for a person’s existence and the support staff work, the rational arrangement of workplaces and machinery, and the optimization of the operating modes of precision equipment.
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