Protection and Enhancement of Hearing in Noise

Abstract

Humans are subjected to noise in many occupational, military, transportation, recreational, and other settings, sometimes with attendant ill effects. Some noises may pose the threat of inducing hearing loss; most noises compromise one's ability to hear signals and other desirable sounds, as well as to communicate via speech. In this chapter, we review the role of noise in human hearing impairment and its effects on signal audibility and speech intelligibility, task performance, and nonauditory responses. Particular emphasis is paid to the needs of the human factors/ergonomics practitioner who is confronted with the objective of protecting individuals' hearing in noise, designing signals so that they are audible and recognizable, and in general, optimizing the use of the auditory sense under poor acoustic conditions. In addition to providing guidance and consensus standards for auditory danger signal design, we provide a review of new technologies in augmented hearing protection. These technologies are aimed at protecting the user's hearing in noise from injury while affording improved audibility for certain applications.