The effect of fitting procedure on hearing protector attenuation.
Merry-CJ; Sizemore-CW; Franks-JR
Ear Hear 1992 Feb; 13(1):11-18
The effects of a laboratory based fitting procedure on hearing protector attenuation were examined. The User Fit fitting procedure was designed to yield hearing protector attenuation values similar to those derived from field studies. Ten normal hearing subjects with little prior experience with hearing protectors participated in a repeated measures design that determined real ear attenuation at threshold for two types of ear plugs, a formable foam plug and a premolded plastic plug. Each subject was tested in two fitting conditions that varied based on type and degree of assistance given to the subjects by the experimenter. Results indicated significant differences in attenuation based on the fitting procedure used. The User Fit method best approximated the field data. A generalized learning effect was noted. While the two User Fit groups received substantially less attenuation than the manufacturers' published data, they received better attenuation than that reported for the plugs in work site data. The authors conclude that experience with ear plugs leads to subsequent improvement in attenuation regardless of the type of ear plug used.
NIOSH-Author; Hearing-protection; Hearing-tests; Protective-equipment; Ear-protection; Noise-protection; Worker-health; Laboratory-testing; Ear-protectors; Analytical-methods
Ear and Hearing