本文件规定了将声学空间限定为满足自由声场要求的消声和半消声空间的方法。 本文件规定了用于量化消声和半消声空间性能的离散频率和宽带测试方法，定义了适用于自由场鉴定的全向声源的鉴定程序，给出了如何呈现结果的细节，并描述了测量的不确定性。 本文件是为各种声学测量目的确定消声和半消声空间而编制的。预计随着时间的推移，各种标准和测试规范将参考本文件，以便对特定测量的消声或半消声空间进行鉴定。附录D提供了试验参数规范和参考文件资格标准的指南。 在没有具体要求或标准的情况下，附录A提供了鉴定标准和测量要求，以鉴定消声和半辐射- 通用声学测量用消声室。 本文描述了测量声环境自由声场性能的发散损失法。

This document specifies methodology for qualifying acoustic spaces as anechoic and hemi-anechoic spaces meeting the requirements of a free sound field. This document specifies discrete-frequency and broad-band test methods for quantifying the performance of anechoic and hemi-anechoic spaces, defines the qualification procedure for an omni-directional sound source suitable for free-field qualification, gives details of how to present the results and describes uncertainties of measurement. This document has been developed for qualifying anechoic and hemi-anechoic spaces for a variety of acoustical measurement purposes. It is expected that, over time, various standards and test codes will refer to this document in order to qualify an anechoic or hemi-anechoic space for a particular measurement. Annex D provides guidelines for the specification of test parameters and qualification criteria for referencing documents. In the absence of specific requirements or criteria, Annex？A provides qualification criteria and measurement requirements to qualify anechoic and hemi-anechoic spaces for general purpose acoustical measurements. This document describes the divergence loss method for measuring the free sound field performance of an acoustic environment.