本标准规定了听力测试室中允许产生可忽略掩蔽的最大允许环境噪声级（MPANL）(≤2 dB）的测试信号，以ANSI S3中规定的参考等效阈值水平呈现。6-1996美国国家标准听力计规范。对于两种听力测试条件（有耳和无耳）和三种测试频率范围（125至8000 Hz、250至8000 Hz和500至8000 Hz），MPANL规定为125至8000 Hz的倍频程和三分之一倍频程间隔。本标准适用于所有听力测试人员以及听力测试室的分销商、安装人员、设计师和制造商。本标准是ANSI S3的修订版。 1-1991美国国家标准听力测试室的最大允许环境噪声级。

This Standard specifies maximum permissible ambient noise levels (MPANLs) allowed in an audiometric test room that produce negligible masking (≤2 dB) of test signals presented at reference equivalent threshold levels specified in ANSI S3.6-1996American National Standard Specification of Audiometers.The MPANLs are specified from 125 to 8000 Hz in octave and one-third octave band intervals for two audiometric testing conditions (ears covered and ears not covered) and for three test frequency ranges (125 to 8000 Hz, 250 to 8000 Hz, and 500 to 8000 Hz).The Standard is intended for use by all persons testing hearing and for distributors, installers, designers, and manufacturers of audiometric test rooms. This standard is a revision of ANSI S3.1-1991American National Standard Maximum Permissible Ambient Noise Levels for Audiometric Test Rooms.