拉萨饮用水源总α放射性测量及其不确定度评定

Measurement of Gross α Radioactivity and Evaluation of its Uncertainty for Drinking Water Source in Lasa

为测量拉萨地区饮用水源总α放射性,并评定测量结果不确定度,依据行业标准,测量该地区饮用水源总α放射性,并根据计算公式和不确定度分析实验评定不确定度主要来源及其大小。测量结果表明:该地区饮用水源总α放射性均较低(≤0.05 Bq·L^(-1))。测量不确定度分别为:样品源测量不确定度为19.31%;仪器效率刻度不确定度为2.28%;源的制备不确定度为1.89%;水样残渣不确定度为0.26%;水样体积不确定度为0.05%。

To measure the level of gross a radioactivity for drinking water source in Lasa and evaluate the uncertainty in the measurement, some water samples have been measured based on industry standard methods. Regaming to these samples, the main sources and quantities of uncertainty in the measurements have also been analyzed and confirmed by calculation formula and uncertainty analysis experiments. The experimental results show that gross a radioactivity for drinking water source in Lasa is relatively low（ ≤0.05 Bq ·L-1 ）. The resuits of uncertainty in the measurements are as following： the uncertainty in sample measurement is 19.31%, in efficiency calibration of the instrument 2.28 %, in preparing source 1.89 %, in sample residues 0.26% ,in sample volume 0.05%.