2018—2022年饮用水中总α、总β放射性测量结果对比分析

Comparative result analysis of totalαand total β radioactivity measurements in water from 2018 to 2022

目的为保证水中总放射性检测能力和评价水平,以减少因方法引入的系统误差。方法实验室每年参加国家、省级组织水中总放射性测量比对考核,抽取2018—2022年饮用水中总α、总β放射性测量结果进行比对分析。组织者每年下发比对方案并提供比对水样,按照比对方案对提供的水样进行检测。检测方法根据《生活饮用水标准检验方法第13部分:放射性指标》(GB/T 5750.13—2006)执行,检测完成后向组织者报送检测结果和相关资料。评判结果根据国际原子能机构(International Atomic Energy Agency,IAEA)对比分析方法进行分析。结果2018—2022年水样测量体积为1.0~1.2L,残渣总重为1009.1~1600.4mg,标准物质粉末计数效率α为9.0%~10.9%,β为25.2%~38.8%;电镀源α最高为90.4%,β最高为56.3%。连续5次比对测量结果显示,总α放射性测量Z值最高为0.42,最低为0;总β放射性测量Z值最高为-0.51,最低为0。2020年水中总α、总β放射性测量能力比对结果判定为合格,其余4年比对结果判定为优秀。结论水中总α、总β放射性测量数据准确,满足生活饮用水放射性监测的有关要求。

Objective To ensure the detection capability and evaluation level of total radioactivity in water in order to reduce systematic errors introduced by the method.Methods The laboratory participated in the comparison and assessment of total radioactivity measurement in water by national and provincial organizations every year.The comparison of the results of totalαand totalβradioactivity in drinking water from 2018 to 2022 for analysis.The organizer issued a comparison program and provided comparison water samples annually,and the provided water samples were tested according to the comparison program.The test method was carried out according to the Standate Test Methods for Drinking Water-Part 13:Radiological Indices(GB/T 5750.13-2006).The test results and related materials were submitted to the organizer after the test was completed.The results were analyzed according to the International Atomic Energy Agency(IAEA)comparative analysis.Results From 2018 to 2022,the measured volume of water samples ranged from 1.0 to 1.2L,the total weight of residue ranged from 1009.1 to 1600.4mg,and the counting efficiency of standardized substance powder ranged from 9.0% to 10.9% for α and from 25.2% to 38.8% for β.The highest electroplating sourceαwas 90.4% and β was 56.3%.The Z-score of totalαradioactivity measurement was 0.42 at the highest and 0 at the lowest in five consecutive comparative measurements.The Z-score of totalβradioactivity measurement was-0.51 at the highest and 0 at the lowest.The comparison results of the ability to measure totalαand totalβradioactivity in water were judged to be qualified in 2020,and the comparison results for the remaining four years were judged to be excellent.Conclusion The measurement data of totalαand totalβradioactivity in water are accurate,and met the relevant requirements of radioactive monitoring in drinking water.