The Combined Effects of Vibration, Noise, and Exposure Duration on Auditory Temporary Threshold Shift
Abstract
To determine the combined effects of noise and vibration on auditory function, the temporary threshold shifts (TTS) of two groups of 10 subjects each were measured as a function of intensity and duration of exposure. Combined noise and vibration was presented to one group for 5 minutes and to the other for 20 minutes. Both groups were exposed to vibration in the Z axis at frequencies of 9 Mz and 18 Hz at intensity levels of 0.475 gz (peak) and 0.950 gz, respectively. Noise levels of 90 dB and 100 dB were presented simultaneously with the vibration. TTS was measured at post exposure recovery times of 0.5, 2.0, 5.0, 10.0, and 20.0 minutes. Although the mean difference was small (0.72 dB), a significantly larger TTS was obtained at 9 Hz than 18 Hz vibration, and 100 dB produced a larger TTS than 90 dB. Significant differences in TTS were also obtained as a function of duration of exposure, and as a function of post exposure recovery time.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1973
- Accession Number
- AD0770285
Entities
People
- Henry C. Sommer
Organizations
- Air Force Research Laboratory