标准氡室氡浓度不确定度评定方法探讨

标准氡室为氡测量仪器的校准提供氡浓度的参考标准,氡室氡浓度可由氡源的氡产生率、补氡时间、氡的自然衰变规律以及吸附/泄漏率等因素进行理论计算,也可用标准氡浓度测量仪测定,同时需要对氡室氡浓度的不确定度进行科学合理的评定.本文分析了这两种氡浓度定值方法的不确定度来源,并分别介绍和探讨了氡浓度值不确定度的评定方法.结果表明:由标准测量仪器测定氡浓度并进行不确定度评定,其方法优于基于氡源参数进行计算所得氡浓度值的不确定度评定方法.

Uncertainties of radon concentration in a standard radon chamber

A standard radon chamber is used as reference standard for calibrating monitors of radon concentration. The radon concentrations can be calculated by radon yield rate of radioactive source, radon-filling time, the decay constant and radon adsorption/leak ratio. It can also be measured by the standard radon monitor, but uncertainties of the measured radon concentration should be evaluated scientifically and rationally. In this paper, sources of the uncertainties were analyzed by two measuring methods of radon concentration, and evaluation methods of the uncertainties were introduced and discussed. The experiment result shows that the uncertainty evaluation method using a standard radon monitor is better than calculation of a radon radioactive source.