Discussion about surface boundary conditions of radon concentration and surface exhalation rate calculations in indoor concrete slab.

In this paper, the rationality of boundary conditions that assume radon concentration at the surface of a concrete slab to be zero, or radon concentration at an infinite point in air to be zero, are discussed in the calculations of radon concentration and surface exhalation rate from a concrete slab. Expressions to calculate radon concentration and surface exhalation rate in indoor concrete slab are given for both boundary conditions.