NF EN ISO 4869-2
Acoustics - Hearing protectors - Part 2 : estimation of effective A-weighted sound pressure levels when hearing protectors are worn
This document specifies three methods (the octave-band, HML and SNR methods) of estimating the A-weighted sound pressure levels effective when hearing protectors are worn. The methods are applicable to either the sound pressure level or the equivalent continuous sound pressure level of the noise. Although primarily intended for steady noise exposures, the methods are also applicable to noises containing impulsive components. It is possible that these methods could not be suitable for use with peak sound pressure level measurements.The octave-band, H, M, L or SNR values are suitable for establishing sound attenuation criteria for selecting or comparing hearing protectors, and/or setting minimum acceptable sound attenuation requirements.
This document specifies three methods (the octave-band, HML and SNR methods) of estimating the A-weighted sound pressure levels effective when hearing protectors are worn. The methods are applicable to either the sound pressure level or the equivalent continuous sound pressure level of the noise. Although primarily intended for steady noise exposures, the methods are also applicable to noises containing impulsive components. It is possible that these methods could not be suitable for use with peak sound pressure level measurements.
The octave-band, H, M, L or SNR values are suitable for establishing sound attenuation criteria for selecting or comparing hearing protectors, and/or setting minimum acceptable sound attenuation requirements.
Le présent document décrit trois méthodes : la méthode par bande d'octave, la méthode HML et la méthode SNR pour estimer les niveaux de pression acoustique effectifs pondérés A en cas d'utilisation de protecteurs individuels contre le bruit. Ces méthodes s'appliquent soit au niveau de pression acoustique, soit au niveau de pression acoustique continu équivalent du bruit. Elles s'appliquent également à des bruits comportant des composantes impulsives mais ne conviennent pas aux mesurages du niveau de pression acoustique de crête.
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1 Domaine d'application
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2 Références normatives
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3 Termes et définitions
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4 Mesurage de l'affaiblissement acoustique des protecteurs individuels contre le bruit
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5 Calcul de la valeur de protection estimée, APVfx, d'un protecteur individuel contre le bruit pour une efficacité de protection choisie
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6 Méthode par bande d'octave
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7 Méthode HML
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8 Méthode SNR
- Annexe A Exemple de calcul des valeurs de protection estimées, APVfx
- Annexe B Exemple de calcul de L' p,A x selon la méthode par bande d'octave
- Annexe C Exemple de calcul et d'utilisation des valeurs H, M et L
- Annexe D Exemple de calcul et d'utilisation des valeurs de SNR
- Annexe E Incertitude des valeurs d'affaiblissement et des indices
- Bibliographie
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