Field attenuation study shows the value of earplug fit testing

Field attenuation study shows the value of earplug fit testing




















The value of earplug fit testing was evident in a field attenuation study conducted by the Howard Leight Acoustical Laboratory on the performance of hearing protection devices. Conducted on over 100 workers at eight different facilities, the study showed that one-third of workers achieved attenuation higher than the published attenuation for their ear plugs, and that another third achieved attenuation within 5 dB of the published rating. But the lowest one-third of workers had attenuation that was more than 5 dB below published attenuation.

The study then interviewed the workers who obtained high attenuation values to determine the common factors that contribute to good earplug fit, and hence, good attenuation in use. Only one factor was found to be a consistent predictor of good fit: one-on-one training. That is, the more often a worker had received individual training in the proper use of hearing protectors, the higher the probability of a good fit. The same was not true for group training, such as watching annual training videos or passing out brochures.
The importance of fit testing as a critical element of one-on-one employee training cannot be overstated. No generalized rating scheme for hearing protectors can be effective without knowing how much attenuation individual workers actually attain. If a safety manager were to supply ear plugs based on the assumption that all ear plugs only achieve half of their published attenuation in the field, then clearly two-thirds of the 100 workers in the study would be seriously overprotected, since they are achieving much higher protection than 50%. Fit testing of hearing protectors bridges the gap between the laboratory estimates of attenuation and the real-world attenuation achieved by workers as they normally wear their protectors.
The National Hearing Conservation Association (NHCA) and the United States Occupational Safety and Health Administration (OSHA) have also endorsed fit testing as a recommended best practice in reducing occupational hearing loss as well as a metric to assess a Hearing Conservation Program’s overall effectiveness.
Additionally, fit testing can be an invaluable tool in reducing compensation claims for noise-induced hearing loss at the workplace. Fit testing records can help document that effective steps were taken to select appropriate hearing protectors, train workers in their proper use, and to document a proper fit with a particular protector. This level of powerful documentation has been unavailable to Hearing Conservation programs in the past.
While many occupational Hearing Conservation programs have the best intentions to ensure that workers are using hearing protectors, the ultimate goal is to ensure that workers wear them properly 100% of the time when exposed to hazardous noise. Ear plug fit testing technology better enables and empowers workers to achieve this goal — and facilitate a life of healthy hearing. 

Post new comment

To prevent automated spam submissions please answer the following question.