Hearing loss in the chinchilla from impact and continuous noise exposure.
Dunn-DE; Davis-RR; Merry-CJ; Franks-JR
J Acoust Soc Am 1991 Oct; 90(4):1979-1985
A determination was made of the relative hazard posed to the peripheral auditory system following impact/impulse and continuous noise of the same power spectrum. Sixteen chinchillas were used in the study. The impact waveform was generated by a hammer striking a nail that was partially embedded in a piece of lumber. The continuous noise was pink noise generated by a General Radio 1382 random noise generator and shaped with a General Radio 1925 one third octave multifilter. The spectrum of the pink noise was shaped to be the same as the impact noise. The impact noise group received 32 656 impacts each day for 5 consecutive days. The continuous noise exposed group was exposed to 4 hours of continuous noise at 110 decibels sound pressure level linear root mean square for 5 consecutive days. Hearing threshold shifts of the impact noise group were significantly greater than the hearing threshold shifts of the continuous noise group. The authors conclude that for the parameters selected the impact noise was more deleterious to hearing than continuous noise with the same acoustic power spectrum.
NIOSH-Author; Hearing-loss; Laboratory-animals; Noise-exposure; Noise-induced-hearing-loss; Industrial-noise; Hearing-threshold
Journal of the Acoustical Society of America