本文件规定了使用液体闪烁计数（LSC）测定所有类型水样中镍-59和镍-63（59Ni和63Ni）活度浓度。使用目前可用的液体闪烁计数器，该测试方法可以测量59Ni活度浓度为50？mBq·l？1和63Ni活度浓度为20？mBq·l？1计数时间为200？最小值和样本量？1,5？l. 笔记？这些性能指标完全取决于各个实验室的测量制度；特别地，59Ni的检测限完全取决于可能存在的63Ni的水平。 应用范围取决于水中溶解物质的量和测量设备的性能特征（背景计数率和检测效率）。 实验室有责任确保本测试方法适用于所测试的水样。

This document specifies the determination of nickel-59 and nickel-63 (⁵⁹Ni and ⁶³Ni) activity concentration in samples of all types of water using liquid scintillation counting (LSC). Using currently available liquid scintillation counters, this test method can measure ⁵⁹Ni activity concentrations of 50 mBq·l^？1 and ⁶³Ni activity concentrations of 20 mBq·l^？1 with a counting time of 200 min and a sample volume of 1,5 l. NOTE      These performance indicators are wholly dependent on the measurement regimes in individual laboratories; in particular, the detection limits for ⁵⁹Ni are entirely dependent on the levels of ⁶³Ni that can be present. The range of application depends on the amount of dissolved material in the water and on the performance characteristics of the measurement equipment (background count rate and detection efficiency). It is the laboratory’s responsibility to ensure the suitability of this test method for the water samples tested.