Noise Attenuating Properties of Earmuffs Worn by Miners. Volume 2: Development of a Laboratory Procedure for the Physical Measurement of Earmuff Attenuation.
NTIS: PB/83-257071 :37 pages
The purpose of this study was to develop and evaluate, in the laboratory, instrumentation and procedures that might allow for the use of physical measurements of earmuff attenuation that would yield results equivalent to those obtained from psychophysical measures of attenuation. The ultimate goal was to evaluate techniques that might subsequently prove feasible for physical measurement of earmuff attenuation in the field. Mining noise spectra were selected and presented to a single subject seated in a diffuse noise field wearing one of the muffs evaluated in the earlier study and fitted with two physical sound measurement systems. A linear system measured the outside noise level and a linear system plus correction filter measured the inside noise level. The measurment indicated that a laboratory method for measuring earmuff attenuation is feasible and comparable with an extensive psychophysical procedure.
CP; Final Contract Report;
NTIS Accession No.
University of Pittsburgh