ASA S12.6-2016 (R2020) PDF Download

The ASA S12.6-2016 (R2020) standard offers instructions for carrying out lab-based tests to evaluate hearing protectors' capacity to passively reduce noise. The required method includes psychophysical examinations of human test subjects to establish the real-ear attenuation at the threshold of hearing.

The standard specifies two fitting techniques: Method A, also referred to as the trained-subject fit, which evaluates the performance of hearing protectors when worn by knowledgeable users who have received careful training in their use; and Method B, also referred to as the inexperienced-subject fit, which approximates the expected attenuation achieved by groups of users with little to no experience using hearing protection.

It's crucial to remember that the accuracy of the attenuation information gathered using these techniques depends on users wearing their hearing protection in the same way that the testers did. The standard does not address rating systems or computational methods for applying attenuation values, nor does it provide minimum performance standards for comfort or wearability.

According to ISO 4869-1:1990, which outlines the subjective method for determining sound attenuation in hearing protectors, ASA S12.6-2016 (R2020) Method A is in line with that standard. The ISO/TS 4869-5:2006 standard, which describes a method for assessing noise reduction utilising fitting by untrained test subjects, relates to Method B.