Efficacy of the U.S. Army policy on hearing conservation programs

Area of Science:

• Occupational Health
• Audiology
• Military Medicine

Background:

• U.S. Army hearing conservation policies were updated, reclassifying non-noise hazardous areas as noise hazardous.
• Employees in these newly classified areas required inclusion in hearing conservation programs.

Purpose of the Study:

• To assess occupational hearing loss in U.S. Army employees between 1987 and 2001.
• To determine if employees working in previously non-hazardous noise areas experienced hearing loss after policy changes.

Main Methods:

• A cohort of 45 demographically similar subjects was selected from a larger group of 211 employees.
• Hearing thresholds were measured and compared between 1987 and 2001.
• Noise-induced hearing loss was predicted based on average noise exposures in 2001.

Main Results:

• No significant changes were observed in the differences between measured and predicted hearing thresholds over the 15-year period.
• Predicted noise-induced hearing thresholds in 2001 were not clinically significant.
• The study found no evidence of significant occupational hearing loss.

Conclusions:

• Subjects were adequately protected from hearing loss under previous classification criteria.
• The application of new hearing conservation criteria provided no additional benefit in preventing hearing loss for this cohort.