Assessment of radiation hazard of concrete and background radiation indoors

Abstract

Simulation of the dose rate of building materials γradiation 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.