Building materials are one of the important radon sources in indoors, second only to soil, so surface radon emission from building materials have been extensively measured. Based on this measured data, several researchers have attempted to predict the indoor radon concentration attributable to radon emitted from building materials such as walls, floors and ceilings. However, an important aspect not considered in this methodology is the correlation between radiation such as r-ray from building materials and radon gas concentration in indoors. This relationship occurs mainly because of the change in the radon diffusion process from the former to the latter configuration. To predict the radon concentration in indoors based on the radiation emission data of building material samples, this paper proposed a semi- empirical model involving radon transport depending on indoor floor plan and the physical characteristics of the building materials as well as surface area, thickness as other input parameters. This model has been established by statistically fitting the ratio of the solution to radon transport equations for the cases of three-dimensional zonal model to a simple mathematical function based on mass balance equation. The model predictions have been validated against the measurements made at a mock-up housing. This model provides an alternative tool to estimate radon emission from building materials without relying on radon emanation factor and bulk density of the materials. Moreover, it may be very useful in the context of developing building codes for radon regulation in new buildings.
展开▼
