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Document ID (ISN)62605
CIS number 94-1373
ISSN - Serial title 0002-8894 - American Industrial Hygiene Association Journal
Year 1993
Convention or series no.
Author(s) Carter N.L., Upfold G.
Title Comparison of earphone and sound field methods for estimating noise attenuation of foam earplugs
Bibliographic information June 1993, Vol.54, No.6, p.307-312. Illus. 16 ref.
Abstract The Real Ear Attenuation at Threshold (REAT) of E-A-R (slow recovery) foam earplugs was determined by three methods of presentation of the test tones during a single fitting of the earplug. The methods were (a) sound-field listening; (b) TDH49 earphone mounted in the shell of a circumaural earmuff; and (c) TDH49 earphone in a Model 51 cushion. Thresholds were tested once under each condition. The mean REAT obtained by the reference (sound field) method could be reliably estimated by both earphone methods for frequencies up to and including 4.0kHz. However, the sound field REAT values of individual subjects could not be predicted reliably from their REAT determined by either type of earphone presentation. Thus, TDH49 earphones in standard audiometric earcushions could be used to check the overall effectiveness of slow recovery foam earplugs in the workplace.
Descriptors (primary) hearing protection; acoustics; audiometric tests; noise level measurement; hearing threshold
Descriptors (secondary) evaluation of equipment; comparative study; noise
Document type D - Periodical articles
Country / State or ProvinceAustralia
Subject(s) Noise, hearing and vibration
Broad subject area(s) Physical hazards
Browse category(ies) Noise
Hearing protection