本文件提供了ISO 11171:2020的背景，以及使用µm（c）作为APC颗粒计数数据的唯一粒度报告方法。本文还总结了使用SRM 2806d候选材料和参考材料（RM）8632a悬浮液对其再现性进行的国际实验室间研究（ILS）的结果。ILS结果为用于APC初级校准的SRM 2806d的认证提供了依据。本文讨论了它们对粒子计数和滤波器测试的影响。购买本文件时可获得的所有当前修订均包含在购买本文件中。

This document provides the background for ISO 11171:2020 and the use of µm(c) as the sole means of reporting particle size for APC particle count data. It also summarizes results of the international inter-laboratory study (ILS) of its reproducibility using SRM 2806d candidate material and suspensions of Reference Material (RM) 8632a. The ILS results provided the basis for certification of SRM 2806d used for primary calibration of APC. Their implications with respect to particle counting and filter testing are discussed in this document.All current amendments available at time of purchase are included with the purchase of this document.