RECOVERY FROM IMPULSE NOISE INDUCED ACOUSTIC TRAUMA
ARMY MEDICAL RESEARCH LAB FORT KNOX KY
Pagination or Media Count:
Recovery from impulse noise induced acoustic trauma was examined in soldiers stationed at Fort Knox, KY. Serial audiograms were obtained on the day of exposure, one day, three days, one week, two weeks, four weeks, six weeks, 12 weeks, four months, five months, and six months post exposure. Recovery from temporary threshold shifts as large as 35 dB was observed at frequencies from 500 - 2,000 cycles. At the higher frequencies shifts of magnitudes as great as 85 dB were observed with good recovery most of the time. Our results indicate that for legal purposes six months is a minimum waiting period necessary to substantiate permanent hearing loss. However, recovery at the speech frequencies is essentially complete in about two weeks.
- Medicine and Medical Research