Effects of Exposure to Intense Low-Frequency Tones on Hearing and Performance

Groups of men were exposed for a 24-h period to either 70-Hz tones at 112.8±10 dB re 0.0002 dyn/cm2 or 300-Hz tones at 113.4±3 dB re 0.0002 dyn/cm2. During the exposure, performance on a sensory-motor task (“RATER”) was tested periodically, and auditory threshold shifts were measured. No decrement in RATER performance was noted for either group. TTSs were moderate except for one subject. The general behavior of the groups and statements made during informal interviews indicated that similar exposure conditions would be well tolerated on a routine basis.