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U.S. Navy Flight Deck Hearing Protection use Trends: Survey Results

05/2006;

ABSTRACT Hearing loss claims have risen steadily in the U.S. Department of Veterans Affairs across all military services decades. The U. S. Navy, with U.S. Air Force and industry partners, is working to improve hearing protection and speech intelligibility for aircraft carrier flight deck crews who work up to 16 hr per day in 130-150 dBA tactical jet aircraft noise. Currently, flight deck crews are required to wear double hearing protection: earplugs and earmuffs (in a cranial helmet). Previous studies indicated this double hearing protection provides approximately 30 dB of noise attenuation when earplugs are inserted correctly and the cranial/earmuffs are well-fit and in good condition. To assess hearing protection practices and estimate noise attenuation levels for active duty flight deck crews, Naval Air Systems Command surveyed 301 U.S. Navy Atlantic and Pacific Fleet flight deck personnel from four aircraft carriers and two amphibious assault ships. The survey included a detailed assessment of cranial helmet fit and maintenance condition; earplug use and insertion depth; anthropometric head size measures; and personal/historical data. This survey identified numerous technological and hearing conservation policy changes to improve hearing protection for flight deck crews. Based on these findings, the U.S. Navy is improving procedural documentation for flight deck hearing protection fit, use, and maintenance as well as developing and fielding enhanced hearing protection technology in joint efforts with the U.S. Air Force.

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