Methods of fit testing hearing protectors, with representative field test data

Numerous published studies in the past 20 years clearly demonstrate that use of laboratory measurements to predict real-world attenuation for groups of workers, or even more problematically for individual workers, is fraught with inaccuracies. Thus, the ability to properly assign hearing protectors in critical high-noise environments or even for lower noise levels when one wishes to closely match attenuation to actual exposure, is questionable. Even if the laboratory data were representative of the actual group using the device, the individual variability is large enough that attempts at predicting one person’s performance from group data can easily err by up to 20 dB (Gauger & Berger 2004).