title: Speech understanding in noise with integrated in-ear and muff-style hearing protection systems.
abstract: Integrated hearing protection systems are designed to enhance free field and radio communications during military operations while protecting against the damaging effects of high-level noise exposure. A study was conducted to compare the effect of increasing the radio volume on the intelligibility of speech over the radios of two candidate systems, in-ear and muff-style, in 85-dBA speech babble noise presented free field. Twenty normal-hearing, English-fluent subjects, half male and half female, were tested in same gender pairs. Alternating as talker and listener, their task was to discriminate consonant-vowel-consonant syllables that contrasted either the initial or final consonant. Percent correct consonant discrimination increased with increases in the radio volume. At the highest volume, subjects achieved 79% with the in-ear device but only 69% with the muff-style device, averaged across the gender of listener/talker pairs and consonant position. Although there was no main effect of gender, female listener/talkers showed a 10% advantage for the final consonant and male listener/talkers showed a 1% advantage for the initial consonant. These results indicate that normal hearing users can achieve reasonably high radio communication scores with integrated in-ear hearing protection in moderately high-level noise that provides both energetic and informational masking. The adequacy of the range of available radio volumes for users with hearing loss has yet to be determined.
authors: Individual Behaviour and Performance Section, Defence Research and Development, Toronto, Ontario, Canada. sharon.abel@drdc-rddc.gc.ca
authors: Sharon M
authors: SM
authors: Abel
authors: Ann
authors: A
authors: Nakashima
authors: Douglas
authors: D
authors: Saunders
mesh_terms: D000704:Analysis of Variance; D004430:Ear Protective Devices / Q000009:adverse effects / Q000592:standards*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008889:Military Personnel; D009623:Noise, Occupational / Q000009:adverse effects / Q000517:prevention & control*; D016273:Occupational Exposure / Q000009:adverse effects / Q000517:prevention & control / Q000592:standards; D011845:Radio / Q000592:standards; D012737:Sex Factors; D013067:Speech Perception; D013334:Students