A Close Look at Hearing Loss
Scott Brueck of NIOSH evaluated the effect of noise on hearing loss at a hammer forge company.
SEATTLE -- Hearing loss was the focus of a Tuesday morning session at AIHce, specifically hearing loss due to noise. As part of the session, Scott Brueck of NIOSH presented his data gathered from evaluating hearing loss at a hammer forge company due to noise.
The study initially started because a local union was concerned about noise exposure at the plant and possible hearing loss in the 100 year-old facility.
Obvious noise at the facility stemmed from the impact of hammer strikes, which was to be expected. Brueck also made note of an impact noise, similar to a gunshot, which was also an issue.
As part of the study, noise was measured in the facility over two days, both by personal noise dosimeters as well as measuring the impulse noise frequency.
The biggest finding from the study? Every job in the facility had noise exposure above the recommended limits. In order to determine how to fix the situation, Brueck then measured the noise effects on humans by placing the provided foam earplugs into the mannequin, which helped reduce noise by roughly 20 db, although that is still not enough to reduce the noise to below the permissible limits.
Unfortunately, these earplugs were not deemed adequately protective, and that is without taking into consideration the fact that employees don't often roll and insert earplugs the right way. This is something Brueck mentioned NIOSH is currently looking into.
The results from the test determined that most employees at the hammer forge facility suffered from hearing loss, including employees under the age of 25. NIOSH recommends the facility decrease the distance that forgings drop into bins or onto chutes and conveyors, and abide by the NIOSH recommended criteria.
The organization also recommended dual hearing protection for all employees as well as a fit test.