Reconciling laboratory and real-world hearing protector testing: The method A versus method B debate

A major area of exploration during Elliott Berger's tenure as chair of ANSI S12 working group 11 was the effort to harmonize laboratory testing of hearing protectors with typical performance in real-world use. S12.6-1997 introduced two variants of the Real-Ear Attenuation (REAT) method with different requirements for subject selection and guidance—Method A (experimenter-supervised fit) and Method B (subject fit). Under Elliott's leadership the working group also produced three papers documenting the motivation for these methods. This paper will summarize these papers then focus on what followed: work spanning 2003 to 2010 that explored the strengths and weaknesses of the two methods, as well as how to distill REAT data to ratings that best convey to an industrial hygienist, in a simple fashion, how much performance to expect from a hearing protector. This work, done in an effort to guide potential improvements to the Noise Reduction Rating by the Environmental Protection Agency, led to three new standards: S12.6-2008, S12.68-2009, and S12.42-2010 as well as a comprehensive paper the author produced with Elliott. This work exemplifies Elliott's incessant and, at times, exhaustively thorough quest for clarity and correctness in the standards process.