Accession Number : ADA297033

Title :   Sound Attenuation and Speech Intelligibility of a Modified Active Noise Reduction (ANR) Headset for Use by P3-C Sensor Operators.

Descriptive Note : Technical Memo

Corporate Author : NAVAL AEROSPACE MEDICAL RESEARCH LAB PENSACOLA FL

Personal Author(s) : Williams, C.E. ; Maxwell, D.W. ; Thomas, G.B.

PDF Url : ADA297033

Report Date : MAY 1995

Pagination or Media Count : 33

Abstract : Sound attenuation and speech intelligibility evaluations were conducted on a modified active noise reduction (ANR) headset being considered for use by sensor operators in Navy P3-C aircraft. Measurements were obtained on 10 male ensigns in the Naval Aviation Flight Training Program. A comparison of the sound attenuation values obtained with the ANR on (combined passive and active attenuation) to values obtained with the ANR off' (passive attenuation) revealed 10-15 (B greater attenuation at 125, 250 and 500 Hz, and 1-5 dB less attenuation at 1000 and 2000 Hz. Speech intelligibility scores obtained with the ANR on were 10% greater than scores obtained with the ANR off' at the two highest noise levels (110 and 115 dB SPL). The results of the evaluations demonstrated that ANR technology could prove beneficial to sensor operators in P3-C acoustical environments. Improved low-frequency noise attenuation should enhance sensor operator performance in monitoring low-frequency acoustical signals and decrease the likelihood that operators would sustain auditory fatigue during typical long-duration flights. The results were instrumental in the decision to proceed with the further development and procurement of the headset for use by sensor operators in the Navy's P3-C community. (MM)

Descriptors :   *SPEECH RECOGNITION, *ACOUSTIC ATTENUATION, *INTELLIGIBILITY, *EARPHONES, SPEECH TRANSMISSION, NOISE REDUCTION, AMBIENT NOISE, STANDARD DEVIATION, MICROPHONES, BACKGROUND NOISE, PATROL AIRCRAFT.

Subject Categories : Acoustics
      Voice Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE