The ambient noise levels in the test rooms affect the workers’s hearing threshold. The present study was designed
to assess the ambient noise levels in the industrial audiometric testing areas to determine if valid hearing tests could be performed in these environments. The ambient noise levels were measured in 141 audiometric testing areas across 47 industries located in Incheon. These results compared with the ANSI S3.1-1999 and OSHA criteria for maximum permissible ambient noise levels. The ambient noise SPLs were highest in the lower frequencies, and this decreased as the frequency increased. For the supraaural earphone, none of the rooms met the ANSI standard. Comparing the room data with the OSHA standard, compliance levels were achieved as follows: 0(0%) at 500 Hz, 4 (2.8%) at 1000 Hz, 27 (19.1%) at 2000 Hz, 134 (95.0%) at 4000 Hz, and 141 (100%) at 8000 Hz. The results of this study strongly indicate that clinical audiometry is being conducted in test rooms having unacceptable or excessive ambient noise levels.