在大多数国家，来自二重唱和非二重唱歌迷的声音都是不受欢迎的。在混响室设施中测量。由于这些昂贵设备的不便和成本，在过去15年中，人们进行了大量的努力，以开发一种成本较低但仍然令人满意的风机管道内声音测量系统。（1-12）英国于1966年（13年）制定了倍频带测量的管道内标准，其他几个欧洲国家和美国也在制定此类标准。然而，许多问题必须解决。在过去两年中，国际标准化组织（ISO）一直在制定标准ISO/TC 43/SCl“连接到排气管或进气管的空气移动装置的声音测量程序”（14） 还有美国供暖、制冷和空气调节协会- 空调工程师公司（ASHRAE）一直在开发标准68P，“测试空气移动设备辐射到管道中的声功率的方法”ISO和ASHRAE草案为实际问题提供了解决方案，有望很快被采纳。普渡大学赫里克实验室对管道内风扇声功率测量进行的研究为这些标准提供了大量背景材料。本文的目的是对本研究进行总结。引文:ASHRAE交易，第80卷，第2部分，蒙特利尔，QC

In most countries, sound from dueted and non-dueted fans is.measured in reverberant room facilities. The inconvenience and cost of such expensive facilities have resulted in extensive efforts in the last fifteen years to develop a less costly, yet still satisfactory in-duct fan sound measurement system. (1-12) The British produced an in-duct standard in 1966 (13) for octave band measurements, and several other European countries and the US have done work on such standards. However, many problems have had to be solved.During the past two years, the International Standards Organization (ISO) has been developing Standard ISO/TC 43/SCl "Sound Measurement Procedures for Air Moving Devices Connected to Either a Discharge Duct or an Inlet Duct." (14) Also the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE) has been developing Standard 68P, "Method of Testing Sound Power Radiated into Ducts from Air Moving Devices."The ISO and ASHRAE drafts have offered solutions to the practical problems and, hopefully, will soon be adopted. Research done at Herrick Laboratories of Purdue University on in-duct fan-sound power measurements provided much of the background material that went into these standards. It is the purpose of this paper to summarize this research.