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Document ID (ISN)20528
CIS number 74-401
ISSN - Serial title 0001-4966 - Journal of the Acoustical Society of America
Year 1973
Convention or series no.
Author(s) Waugh R.
Title dBA attenuation of ear protectors.
Bibliographic information Feb. 1973, Vol.53, No.2, p.440-447. Illus. 14 ref.
Abstract The adoption of hearing damage risk criteria expressed in A-weighted sound levels (dBA) and the consequent measurement of auditory hazards in dBA have made it necessary to measure dBA attenuation of hearing protective equipment. A study was therefore carried out to develop a method of calculating dBA attenuation of any continuous broad-band industrial noise when only the weighted sound levels of the noise are known. dBA attenuation of 30 hearing protectors was calculated in exposure to 619 industrial noise spectra. It was found that the same hearing protector may offer 20 dB more dBA attenuation to one noise than to another, but that noises of like C - A value (C-weighted value minus A-weighted value) are subject to approximately the same attenuation. 5 classes of C - A value are proposed and the average dBA attenuation values of each hearing protector for each noise class are calculated. With this information it is possible to select adequate ear protectors even though only the C-weighted and A-weighted sound levels of the noise are known.
Descriptors (primary) hearing protection; sound attenuation; noise
Descriptors (secondary) earplugs; computer analysis; pure-tone audiometry; earmuffs
Document type -
Subject(s) Noise, hearing and vibration
Broad subject area(s)
Browse category(ies) Noise
Hearing protection