Chao C Y, Tung T C
Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay.
Health Phys. 1999 Jun;76(6):675-81. doi: 10.1097/00004032-199906000-00011.
Small-scale chamber experiments were conducted to investigate the radon emanation rates of commonly used building materials such as bare concrete, granite, red brick, and sand brick. It has been found that back diffusion caused by the accumulation of radon in the indoor environment has significant influence on the radon emanation rate. The radon emanation rate can be expressed as the summation of an initial emanation rate and the product of a specific back diffusion coefficient and the indoor radon level. In some occasions the radon emanation rate can be significantly lower than its initial value. A database was developed summarizing results from 26 samples. The influence of relative humidity on the radon emanation characteristics has also been discussed. Separate tests were done by coating the four sides of the building material with silicone gel to simulate a one-dimensional radon diffusion geometry. The results show that a factor has to be included when the three-dimensional test results are used to describe one-dimensional geometry, such as radon emanation from building wall surfaces.
进行了小规模的室内实验，以研究常用建筑材料如裸混凝土、花岗岩、红砖和砂砖的氡析出率。研究发现，室内环境中氡的积累引起的反向扩散对氡析出率有显著影响。氡析出率可表示为初始析出率与特定反向扩散系数与室内氡水平乘积之和。在某些情况下，氡析出率可能显著低于其初始值。开发了一个数据库，汇总了26个样本的结果。还讨论了相对湿度对氡析出特性的影响。通过用硅胶涂覆建筑材料的四个面来模拟一维氡扩散几何形状进行了单独测试。结果表明，当使用三维测试结果来描述一维几何形状（如建筑墙面的氡析出）时，必须包含一个因子。
