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Document ID (ISN)58793
CIS number 92-1686
ISSN - Serial title 0736-2501 - Noise Control Engineering Journal
Year 1992
Convention or series no.
Author(s) Pääkkönen R.
Title Effects of cup, cushion, band force, foam lining and various design parameters on the attenuation of earmuffs
Bibliographic information Mar.-Apr. 1992, Vol.38, No.2, p.59-65. Illus. 20 ref.
Abstract Commercial and custom-made earmuffs were tested on volunteers by a miniature microphone method in an anechoic room and in a low-frequency chamber, and on a simulator in an acoustic tunnel. Changes in the cup or its foam lining improved attenuation by as much as 10dB. Changes in the material or shape of the cushion improved attenuation by up to 4dB. Effects of modifications were frequency-dependent. Breaks in the cushion or holes in the cup degraded attenuation by up to 30dB, whereas producing a gap between the cushion and the head degraded attenuation by less than 10dB. In practice, tight fit and an increase in sound absorption inside the cup were most important for improving sound attenuation.
Descriptors (primary) earmuffs; sound attenuation
Descriptors (secondary) evaluation of equipment
Document type D - Periodical articles
Country / State or ProvinceFinland
Subject(s) Noise, hearing and vibration
Broad subject area(s) Physical hazards
Browse category(ies) Noise
Hearing protection