Development of Phonetically Balanced Phrase Lists Typical of Communication in Noisy Work Environments.

Abstract

The existing speech corpora are of limited value in assessing the combined effects of hearing loss, hearing protection, and noise on peech intelligibility in the work place. One reason for this is the differences between the acoustic characteristics typical of the elevated vocal effort in the work place and those typical of the normal vocal effort used in recording various existing speech corpora. The other reason for the limited value of the existing tests is related to the differences in nonacoustic factors (linguistic structure, predictability of the messages, etc.) between the available speech corpora and the actual messages used in the work place. In this study a speech test designed for use in industrial work places has been developed. The test material consists of eight 20-phrase lists. The lists are phonetically balanced and of approximately equal difficulty. The variability among lists is greatest at very low sensation levels and decreases progressively as the sensation level increases.