A simple simulation model to estimate indoor absorbed γ radiation doses in air

Abstract

The indoor absorbed gamma dose rate in air is calculated by a simple theoretical model. The dose inside any room is put in a relation to that of some reference room by using some correction factors that are estimated by the MCNP5 simulation code. These correction factors reflect the effect of the different elements that control the value of the dose. The radiation considered in this study is the natural one due to the uranium series 238U, the thorium series 232Th and the potassium radionuclide 40K. The affecting elements include the main ones like the thickness, density and dimensions of the different parts of the room, in addition to some other factors, e.g., the division of some walls and the existence of adjacent rooms, doors, windows and partial inner walls. A special factor is the exhalation of radon from building materials. The scheme of studying that last factor is utilized to calculate radon exhalation rates from both the building materials and the soil.