标准摘要
[中文适用范围]： 本国际标准为基于培养微生物颗粒计数的定量微生物分析中不确定度评估提供指南。它涵盖所有菌落计数方法变体和最可能数估计。包括两种方法：分量法（也称为自下而上或逐步法）和修改的全局（自上而下）方法。目的是规定如何获得实验室内部操作变异性和最终测试结果的组合不确定度值。这些程序不适用于除计数方法以外的其他方法。 [外文原描述]： This International Standard gives guidelines for the evaluation of uncertainty in quantitative microbiological analyses based on enumeration of microbial particles by culture. It covers all variants of colony count methods and most probable number estimates. Two approaches, the component (also known as bottom‑up or step‑by‑step) and a modified global (top‑down) approach are included. The aim is to specify how values of intralaboratory operational variability and combined uncertainty for final test results can be obtained. The procedures are not applicable to methods other than enumeration methods. NOTE 1 Most annexes are normative. However, only the annexes relevant to each case are to be applied. If the choice is the global approach, then all normative annexes that belong to the component approach can be skipped and vice versa. NOTE 2 Pre-analytical sampling variance at the source is outside the scope of this International Standard, but needs to be addressed in sampling designs and monitoring programmes. NOTE 3 The doubt or uncertainty of decisions based on the use of analytical results whose uncertainty has been estimated is outside the scope of this International Standard. NOTE 4 The extra‑analytical variations observed in proficiency tests and intercalibration schemes are also not detailed in this International Standard, but it is necessary to take them into consideration in analytical control. The use of intercalibration data in uncertainty estimation offers the possibility for the bias between laboratories to be included (Nordtest Report TR 537[12]).
英文名称Water quality — The variability of test results and the uncertainty of measurement of microbiological enumeration methods