指出供暖、通风和空调系统产生的低频噪声多年来一直是一个严重且日益严重的问题。由于目前的研究涉及ASHE评估方法和ASHE评估方法的低频率问题，因此RAE评估方法目前还不足以解决这一问题。重点关注更基本的问题，例如这些低频问题的来源是什么，以及为什么近年来它们变得如此普遍。说明越来越明显的是，使用直接驱动系统和变频电源的成套空气处理设备最不可能产生低频风扇噪音问题。关键词:供暖、通风、空调、噪音、风扇、频率。引用:研讨会，ASHRAE Trans。，1993年，第99卷，第2部分，论文编号DE-93-1-1429-439，图7，表2，参考文献。

Points out that awareness of low-frequency noise generated by heating, ventilation and air conditioning systems has been a serious and increasing problem for many years. Reports that ASHRAE is currently funding research into aspects of the problem that involve the measurement and assessment of low-frequency noise because present test procedures and rating methods are inadequate for evaluating this class of problem. Focuses on more basic questions such as what are the sources of these low-frequency problems and why they have become so prevalent in recent years. States it is becoming obvious that packaged air-handling equipment using direct drive systems and variable-frequency power are the least likely to create problems with low-frequency fan noise.KEYWORDS: Heating, ventilation, air conditioning, noise, fans, frequency.