Foreword
Introduction
Scope
Normative references
Terms and definitions
Measurement of sound attenuation of hearing protectors
Calculation of the assumed protection value, APV, of a hearing protector for a selected protection performance
Octave-band method
HML method
General
Calculation of H, M and L values
Application of HML method for estimation of the effective A-weighted sound pressure level
SNR method
General
Calculation of SNR values
Application of SNR method for estimation of the effective A-weighted sound pressure level
Example of the calculation of the assumed protection values, APV (informative)
Example of the calculation of L′ according to the octave-band method (informative)
Example of the calculation and use of H, M and L values (informative)
Calculation of H, M and L values for a particular hearing protector
Use of H, M and L values to estimate L′ for a particular hearing protector in a specific noise situation
Example of the calculation and use of SNR values (informative)
Calculation of the SNR value for a particular hearing protector
Use of the SNR value to estimate L′ for a particular hearing protector in a specific noise situation for which L is known
Use of the SNR value to estimate L′ for a particular hearing protector in a specific noise situation in which the A-weighted sound pressure level has been measured and a reasonable estimate of (L − L) is available
Uncertainty of attenuation values and ratings (informative)
General
Example of uncertainty
Bibliography