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Document ID (ISN)32553
CIS number 79-1901
ISSN - Serial title 0509-6510 - Prace Centralnego instytutu ochrony pracy
Year 1979
Convention or series no.
Author(s) Trynkowska D., Michalski R.
Title Principles for the classification and choice of hearing protectors
Original title Zasady klasyfikacji i doboru ochronników słuchu [in Polish]
Bibliographic information 1979, Vol.29, No.101, p.177-189. Illus. 15 ref.
Abstract Results of tests carried out in Poland by the Central Institute for Worker Protection (CIOP) on 22 types of earmuffs, 1 acoustic helmet and 5 types of earplugs. The tests consisted in determining, by the "hearing threshold shift" method, the acoustic efficacy of hearing protectors for 5 standardised noise spectra obtained from mean spectra established for each classified category of noise produced in Polish industrial plants. Analysis of attenuation curves in relation to the spectral distribution index enabled certain laws to be established which were then used as a basis to devise certain simplified methods for the choice and classification of hearing protectors. The selection method reduces workplace noise measurement requirements; only weighted levels LA, in dB(A), and LC, in dB(C) need be measured. The system of classification, based on the protection afforded according to the noise spectrum, comprises 4 categories: A and B for protectors which attenuate all noise, and B and C for those which attenuate only noise with preponderant medium and high frequencies.
Descriptors (primary) hearing protection; earmuffs; earplugs; sound attenuation
Descriptors (secondary) evaluation of equipment; sound frequency; classification; noise measurement; acoustic helmets
Document type -
Subject(s) Noise, hearing and vibration
Broad subject area(s)
Browse category(ies) Noise
Hearing protection