Citation

Wagstaff AS, Tvete O, Ludvigsen B. Aviat. Space Environ. Med. 1996; 67(11): 1034-1038.

Affiliation

Royal Norwegian Air Force Institute of Aviation Medicine, Oslo, Norway.

Copyright

(Copyright © 1996, Aerospace Medical Association)

DOI

unavailable

PMID

8908340

Abstract

INTRODUCTION: Speech intelligibility tests in recorded helicopter noise were performed on 10 subjects with normal hearing, using a Peltor aviation headset. The subjects acted as their own controls, a pair of sunglasses being the only variable factor. METHODS: Noise levels were also measured at the tympanic membrane in one of the test subjects for 7 consecutive fittings of the headset, with and without glasses. RESULTS: Results showed a substantial decrease in speech intelligibility when wearing glasses, being most marked for critical signal-to-noise ratios and the most difficult speech material. Changes were statistically highly significant. Average speech intelligibility scores decreased from 68% to 29% for one-syllable words when wearing glasses at critical signal-to-noise ratios. Noise measurements at the tympanic membrane in one subject showed a low-frequency leakage varying between consecutive fittings. CONCLUSION: Our findings show that even small leakages due to fitting of the headset or helmet should be avoided, particularly in noisy aircraft with communication-demanding mission profiles.

Language: en