本文件涉及根据ISO 5801标准在标准化气道中测试的风机的空气性能与在实际现场条件下测试的风机性能相比可能出现的退化。它涉及许多通用类型的风扇和配件的性能。给出的结果仅供参考，仅提供趋势，因为系统效果取决于风机和干扰部件的精确几何形状。 本文件中的试验数据取自20年前由NEL（英国国家工程实验室）进行的广泛试验项目，主要针对轴流和离心风机。 数据还来自ASHRAE资助的几个研究项目，其中一些项目正在芝加哥AMCA实验室进行，以及单个风扇制造商之前发布的结果。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 deals with the likely degradation of air performance of fans tested in standardized airways in accordance with ISO 5801 when compared with the performance of fans tested under actual site conditions. It deals with the performance of a number of generic types of fan and fittings. The results given are intended as guidelines and only provide trends, as the system effect depends on the exact geometry of the fan and disturbing component. The test data presented in this document are taken from an extensive experimental program conducted 20 years ago by NEL (National Engineering Laboratory, UK), mainly on axial and centrifugal fans. Data are also taken from several research projects financially supported by ASHRAE, some of them being carried out in the AMCA laboratory in Chicago, as well as from results published previously by individual fan manufacturers.All current amendments available at time of purchase are included with the purchase of this document.