本文件规定了测量和报告信息技术和电信设备噪声排放的程序。 注1:本文件被视为此类设备噪声测试规范（见3.1.2）的一部分，并基于基本噪声排放标准（见3.1.1）ISO 3741、ISO 3744、ISO 3745、ISO 9295和ISO 11201。 基本排放量是A加权声功率级，可用于比较同一类型但不同制造商的设备，或用于比较不同的设备。 为了避免对现有设施和经验的过度限制，本文件规定了确定声功率级的三个基本噪声排放标准。ISO 3741规定了混响试验室中的比较测量；ISO 3744和ISO 3745规定了反射面上基本自由场的测量。 在确定机器的声功率级时，可根据本文件选择并专门使用这三个基本噪声排放标准中的任何一个。 根据基本噪声排放标准ISO 11201，在操作员位置或旁观者位置确定的A加权发射声压级补充了A加权声功率级。该声压级不是工作站的噪声干扰级（见3.2.12），但它有助于识别可能对操作员和旁观者造成烦扰、活动干扰或听力损害的任何潜在问题。 附录D中规定了确定噪声发射是否包括显著离散音调的方法。 本文件适用于型式试验，并为制造商和试验实验室提供了获得可比结果的方法。 本文件规定的方法允许测定单独测试的功能单元（见3.1.4）的噪声发射水平。 本程序适用于发出宽带噪声、窄带噪声和含有离散频率成分的噪声或脉冲噪声的设备。 获得的声功率和发射声压级可用于噪声发射声明和比较目的（见ISO 9296[3]）。 注2:获得的声功率级和发射声压级不被视为安装噪声干扰级；然而，它们可用于安装规划（见ECMA TR/27[11]）。 如果为同一生产系列的多个功能单元确定获得的声功率级，则可以使用它们来确定该生产系列的统计值（见ISO 9296[3]）。

This document specifies procedures for measuring and reporting the noise emission of information technology and telecommunications equipment. NOTE 1 This document is considered part of a noise test code (see 3.1.2) for this type of equipment and is based on basic noise emission standards (see 3.1.1) ISO 3741, ISO 3744, ISO 3745, ISO 9295 and ISO 11201. The basic emission quantity is the A-weighted sound power level, which can be used for comparing equipment of the same type but from different manufacturers, or for comparing different equipment. Three basic noise emission standards for determination of the sound power levels are specified in this document in order to avoid undue restriction on existing facilities and experience. ISO 3741 specifies comparison measurements in a reverberation test room; ISO 3744 and ISO 3745 specify measurements in an essentially free field over a reflecting plane. Any of these three basic noise emission standards can be selected and used exclusively in accordance with this document when determining sound power levels of a machine. The A-weighted sound power level is supplemented by the A-weighted emission sound pressure level determined at the operator position or the bystander positions, based on basic noise emission standard ISO 11201. This sound pressure level is not a level of noise immission at a work station (see 3.2.12), but it can assist in identifying any potential problems that could cause annoyance, activity interference or hearing damage to operators and bystanders. Methods for determination of whether the noise emission includes prominent discrete tones are specified in Annex D. This document is suitable for type tests and provides methods for manufacturers and testing laboratories to obtain comparable results. The methods specified in this document allow the determination of noise emission levels for a functional unit (see 3.1.4) tested individually. The procedures apply to equipment which emits broad-band noise, narrow-band noise and noise which contains discrete-frequency components, or impulsive noise. The sound power and emission sound pressure levels obtained can serve noise emission declaration and comparison purposes (see ISO 9296[3]). NOTE 2 The sound power levels and emission sound pressure levels obtained are not intended to be considered as installation noise immission levels; however, they can be used for installation planning (see ECMA TR/27[11]). If sound power levels obtained are determined for a number of functional units of the same production series, they can be used to determine a statistical value for that production series (see ISO 9296[3]).