环境空气中氚化水测定方法验证

Verification of a method for determination of tritiated water in ambient air

目的实验验证干燥剂吸附采样-高温负压解吸液态水(含HTO)-液体闪烁计数器测量的环境空气中氚化水测定方法的精密度、正确度等指标,为环境空气中氚化水监测标准方法制定提供技术支撑。方法通过对不同活度浓度环境样品的采集、测试和测量结果分析,验证多组样品分析结果相对标准偏差、加标回收率;评定方法不确定度,明确主要不确定度分量,分析方法测量结果可靠性;通过不同方法比对实验,检验不同方法测试结果的差异。结果多组样品分析结果相对标准偏差范围为6.7%~7.9%,加标回收率范围为95.7%~97.3%,不确定度受样品测量计数率影响较大,与冷凝采样分析结果比较无统计学差异。结论该方法精密度、正确度等满足生态环境主管部门对环境空气中氚化水监测要求,可在环境空气中氚化水监测工作中推广使用。

Objective To experimentally verify the precision and accuracy of determining tritiated water in ambient air using the desiccant adsorption sampling–high temperature negative pressure desorption of liquid water(containing HTO)–liquid Scintillation counter method,and to provide technical support for developing standard methods for monitoring tritiated water in ambient air.Methods The relative standard deviation and recovery of multi-group samples were verified by collecting,testing,and analyzing environmental samples with different activity concentrations.The uncertainty of the method was evaluated,the main uncertainty components were identified,and the reliability of measurement results was analyzed.Through experimental comparison of different methods,the differences in the test results of different methods were examined.Results The relative standard deviation of multiple samples ranged from 6.7%to 7.9%,the recovery ranged from 95.7%to 97.3%,and the uncertainty was greatly affected by the sample counting rate,with no significant difference as compared to condensation sampling method.Conclusion The precision and accuracy of this method meet the requirements of environmental authorities for monitoring tritiated water in ambient air,and it can be widely used in the monitoring of tritiated water in ambient air.