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Document ID (ISN)56717
CIS number 91-1685
ISSN - Serial title 0002-8894 - American Industrial Hygiene Association Journal
Year 1991
Convention or series no.
Author(s) Stokes J.P., Royster L.H., Pearson R.G., Royster J.D.
Title Subjective evaluation of a prototype earmuff exhibiting flat and nonlinear attenuation characteristics
Bibliographic information Feb. 1991, Vol.52, No.2, p.52-60. Illus. 22 ref.
Abstract Subjective user reponses were obtained for a test earmuff exhibiting approximately flat (uniform) attenuation of about 25dB from 500 to 8000Hz for sound pressure levels (SPLs) less than 120dB. At SPLs above 120dB, the test earmuff exhibited nonlinear (level-dependent) attenuation characteristics such that noise reduction increased with increasing sound level. The study population consisted of police officers executing a series of firing programmes during two sequential and identical relays. The study subjects wore either the test earmuff or a comparable conventional earmuff during the first relay, then the alternate protector for the second relay with the order counterbalanced. Results indicated a significant preference for the test earmuff in three comparison areas: comfort, perceived hearing protection, and speech understanding. The study demonstrates that ammunition type and level of noise exposure contributed significantly to a preference in favor of the test earmuff. The subjects who used the quietest of the ammunition types rated the test earmuff significantly better than the remaining subjects with respect to speech understanding.
Descriptors (primary) hearing protection; noise; gunfire noise; noise control; earmuffs; firearms
Descriptors (secondary) subjective assessment; sound attenuation; speech interference
Document type D - Periodical articles
Country / State or ProvinceUSA
Subject(s) Noise, hearing and vibration
Broad subject area(s) Physical hazards
Browse category(ies) Noise
Hearing protection