Second field investigation of noise reduction afforded by insert-type hearing protectors.
Lempert BL; Edwards RG
Inter-Noise 82, Proceedings of the International Conference on Noise Control Engineering, May 17-19, 1982, San Francisco, California 1982 May; :413-414
The effectiveness of insert type hearing protectors was reviewed. These protective devices were sanctioned by OSHA for temporary use by workers to reduce noise exposure until adequate engineering noise control measures were in place. Parameters important in the evaluation of earplug effectiveness included attenuation, comfort, and ease of insertion and removal. Attenuation data for the hearing protectors derived from best fit laboratory results in the test frequency range of 125 to 8000 hertz were published by NIOSH in 1975. These data provided the basis for manufacturers' noise reduction ratings. Two field studies were conducted by NIOSH to assess the relationship between noise protection and worker earplug use on site. One study examined the use of two preformed earplugs and one user formed earplug and showed that half of the workers tested were receiving less than one third of the potential attenuation predicted by laboratory tests due to improper wearing of the hearing protectors. A second study assessing the performance of self molding acoustic wool matting with a preformed plastic cover earplug, a self molding expandable foam plug, and a custom molded hearing protector indicated that the workers were receiving about half of the potential attenuation power predicted by the manufacturer. The proper selection of earplug style was directly related to the amount of protection afforded, with the self molding and custom molded hearing protectors showing the best attenuation properties.
Occupational-exposure; Noise-control; Noise-induced-hearing-loss; Noise-protection; Acoustic-absorption; Workplace-studies; Worker-health; Ear-protection; Sound-propagation; Sound-attenuation
Hearing Loss; Disease and Injury; Noise-induced-hearing-loss
Inter-Noise 82, Proceedings of the International Conference on Noise Control Engineering, May 17-19, 1982, San Francisco, California