Noise and Hearing Loss. NIH Consensus Development Conference Consensus Statement (January 22-24, 1990). Volume 8, Number 1.

This report is the product of a National Institutes of Health Consensus Development Conference on Noise and Hearing Loss which addressed the characteristics of noise-induced hearing loss, acoustic parameters of hazardous noise exposure, individual and age-specific susceptibility, and prevention strategies. The report examines the incidence of hearing loss and exposure to noise, a definition of noise-induced hearing loss (NIHL), assessment of NIHL, types of sounds that can damage hearing, factors determining an individual's susceptibility to NIHL, prevention strategies, and directions for future research. The consensus panel concluded that sounds of sufficient intensity and duration will damage the ear and result in temporary or permanent hearing loss at any age. Sound levels of less than 75 decibels are unlikely to cause permanent hearing loss, while sound levels above 85 decibels with exposures of 8 hours per day will produce permanent hearing loss after many years. Current scientific knowledge is inadequate to predict that any particular individual will be safe when exposed to a hazardous noise. Strategies to prevent damage from sound exposure should include the use of individual hearing protection devices, education programs beginning with school-age children, consumer guidance, increased product noise labeling, and hearing conservation programs for occupational settings. (JDD)