Field attenuation of hearing protection devices

Although personal hearing protection devices should not be the permanent answer to noise exposure reduction, their use represents a temporary solution until adequate engineering controls or administrative strategies reduce the noise hazard. This paper describes the researches aimed at developing standardised test methods that reduce the discrepancy between the labelled attenuation of hearing protection devices and the much lower attenuation actually attained by workers using these devices on the job. First, it reports a short review of the technical procedure standardised world-wide and currently used to assess the attenuation of hearing protectors. Second, it reviews the results of real-world studies conducted in order to determine the field performance of these personal devices. Then, it outlines a new standardised testing procedure that should yield a more realistic estimate of the field performance of hearing protection devices.