本标准包括用于液体闪烁计数器性能评估的检查源规范。本标准中考虑的性能指标是计数系统效率样品的再现性和背景计数率性能评估检查源的准备第条给出了此处使用的一些术语的定义。本标准不包括淬火未知样品的样品活度计算。因此，本标准不涉及样品制备、效率相关性（淬火校正）程序或未知放射性核素的识别。

The specifications for check sources to be used in the evaluation of liquid-scintillation counter performance are included in this standard. Measures of performance considered in this standard are Counting system efficiencyReproducibility of sample and background count ratesPreparation of check sources for performance evaluationDefinitions of some terms used here are given in Clause.This standard does not cover the calculation of sample activity for quenched unknown samples. Accordingly, this standard does not deal with sample preparation, efficiency correlation (quench correction) procedures, or identification of unknown radionuclides.