Attenuation characteristics of fit-compromised earmuffs and various non-standard hearing protectors

Excessive noise exposure can be successfully mitigated by proper use of legitimate hearing protection devices. However, real-life circumstances sometimes drive people to use compromised or alternative means of protection. This paper reports attenuation data measured in the 3M E•A•RCAL facility over several years, in conformance with ANSI real-ear attenuation at threshold test standards (S3.19-1974, S12.6-1984, and S12.6-2008 Method A) and also provides, for comparison, one dataset from the open literature (fingers/palms). The loss of attenuation was measured for various earmuffs worn in less than ideal conditions, including earmuffs worn in conjunction with various safety glasses, hairnets, head covers, hoods, earmuff cushion covers, and baseball style caps. Data were also obtained for non-standard means of blocking sound, including long hair, cotton balls, and even use of palms and/or fingers to block the ears. Results demonstrated that the effects on earmuff attenuation varied from none at all (suitable...