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Improvements in sound attenuation performance with earplugs following checklist-based self-practice
Koko Takahashi1, Shoko Kawaniai, Jinro Inoue
1Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Japan, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Abstract:
The hearing protectors most often used in noisy workplaces are earplugs. The sound attenuation performance of earplugs depends in part on the user's skill and knowledge. This study sought to clarify whether individual training and self-practice based on a checklist can improve sound attenuation. Measurements were performed as follows: Ten subjects, including both men and women, were provided with semi-insert earplugs (E-A-R flex 350-1001) and wore them based only on the printed instructions of the product. Sound attenuation was measured from 125 Hz to 8000 Hz, in accordance with JIS T8161-1983. Intervention was provided through 5 minute individual training with oral and written instructions, followed by 10 minute self-practice each day for 7 days. Sound attenuation was then measured once again. The results indicated significantly improved attenuation, ranging from 7.7 dB to 11.7 dB, in all frequencies following training, confirming the effectiveness of the intervention. This is an easy and effective method for training workers in how to wear earplugs most effectively.
