氡室建标中几个技术问题的解决办法

Solution of Building the Standard Laboratory of Radon

标准氡室在氡浓度量值溯源和传递中起着重要作用。为了保证测氡仪量值统一、准确可靠,建立了测氡仪检定装置。针对在建立标准过程中出现的流气式氡源泄漏、氡室实验累积氡浓度值与理论值不一致和液体镭源结晶等问题,重点研究多重密封、改造洗气管路、优化洗气模式及多重过滤等技术方法,并建立氡室累积氡浓度经验曲线和质量管理措施等。按照新建立的实验方法和实验流程,氡室实验调节氡浓度和理论累积氡浓度相对偏差在±3.8%以内,液体镭源长期稳定性在0.7%以内,符合氡室建标的计量性能要求。

The standard laboratory of radon plays an important role in the tracing and transmitting of value of radon concentration. But there are many problems in the process of building the standard laboratory of radon, which are gas leaking of solid radon source, inconformity between theoretical value and experimental value of radon concentration in laboratory, and crystallization of liquid radon source. Measures were taken to solve these problems, such as changing the gas washing canal of radon, optimizing the model of gas washing, multiple sealing and filtering, building empirical curve, and so on. It indicated that the relative deviation between theoretical value and experimental value of radon concentration in laboratory was less than ±3.8% , and the long time stability of liquid radon source less than 0. 7%, which meet the requirment of mcasurment and methods established metrology.