1.1 本试验方法涵盖了对气动排气消声器的声学和机械性能的实验室测量，该消声器设计用于使连接到尺寸高达 3. / 4. 在里面NPT。本试验方法不适用于执行有用工作的排气，例如零件输送、喷射或清洁。该测试方法使用A加权声级测量来评估声学性能。 1.2 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 第节给出了具体的预防说明 8. . 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法允许评估设计用于使压缩气体排气（通常为空气）静音的气动排气消声器的声学和机械性能。制造商可以使用这些数据来评估或改进其产品，用户也可以使用这些数据来选择或指定消声器。使用这种测量方法获得的数据允许对竞争产品进行性能比较，并有助于选择合适的设备。 5.2 当应用涉及需要快速排出压缩空气或其他气体的机械或设备时，流速是需要考虑的重要参数。 例如，在自动气动压力机中，必须快速排出压缩空气，以避免过早的第二个循环。因此，除了声学性能外，还报告了流量比。

1.1 This test method covers the laboratory measurement of both the acoustical and mechanical performance of pneumatic exhaust silencers designed for quieting compressed gas (usually air) exhausts from orifices connected to pipe sizes up to 3 / 4 in. NPT. This test method is not applicable for exhausts performing useful work, such as part conveying, ejection, or cleaning. This test method evaluates acoustical performance using A-weighted sound level measurements. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8 . 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method permits the evaluation of both the acoustical and mechanical performance of pneumatic exhaust silencers designed for quieting compressed gas exhausts (usually air). The data can be used by manufacturers to assess or improve their products, or by users to select or specify a silencer. The data acquired using this measurement method allow for performance comparisons of competitive products and aid in the selection of an appropriate device. 5.2 Flow rate is an important parameter to consider when the application involves machinery or equipment that requires compressed air or other gases to be exhausted rapidly. For example, in an automatic pneumatic press, compressed air must be exhausted rapidly to avoid a premature second cycle. For this reason, flow ratio is reported in addition to acoustical performance.