密闭腔体法(closed chamber method)是目前建材氡析出率测量中使用较为广泛的一种方法。使用密闭腔体法测量建材氡析出率,在建材的前处理上,大体上将长方体建材分为完全裸露、包裹留下一面和留下两面三种方法进行测量。本文从建材氡析出率测量的基本理论模型出发,细致比较分析了不同包裹方法测量得到的氡析出率的真实涵义,并结合理论分析和实验验证,提出了合理的修正方法,认为包裹留一面和留两面适合作为建材氡析出率的测量方法。
Closed Chamber Methods have been widely used to measure radon exhalation rate from building material.It is found,however,that different sealing methods of treatments on building materials before measurements were used in different laboratories worldwide.Taking a brick as an example,as treatment on building materials,sealing up 4 sides,5 sides or totally baring were reported.To understand and confirm the differences between different treatments on building materials,theoretical analysis were carried out on basis of the definition and measuring model of radon exhalation rate from building materials in this study.The real meaning and the matter of each different sealing method were analyzed in detail,and experimental study was also performed.In summary,the two methods of sealing up 4 sides and sealing up 5 sides were regarded as appropriate methods to measuring exhalation rate but reasonable correction was necessary.