Fit Testing of Hearing Protection Devices and Its Integration with Hearing Conservation Programs in the Workplace: A Literature Review
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Abstract
Noise-induced hearing loss (NIHL) remains a significant occupational health concern in several countries, including Thailand. Although hearing conservation programs (HCPs) are mandated by the Department of Labour Protection and Welfare, Ministry of Labour, the calculation of noise attenuation based on the Noise Reduction Rating (NRR) provided by hearing protection device (HPD) manufacturers often fails to reflect the actual protection achieved in real-world use. To address this discrepancy, fit testing has been developed as a method to assess the Personal Attenuation Rating (PAR), providing a more accurate measurement of individual noise attenuation while wearing HPDs. A number of previous studies have demonstrated that fit testing alongside extensive training programs significantly enhances the effectiveness of HPD use among workers. However, in the context of Thailand, studies on the effectiveness of fit testing remain limited. This literature review examined the problem of noise-induced hearing loss among workers, synthesized existing knowledge on hearing conservation programs implemented across different countries, and explored the concept of hearing protection device fit testing and how to integrate fit testing into hearing conservation training programs. The review further proposes comprehensive recommendations for policymakers to strengthen legislation on hearing conservation and to promote best practices among industrial organizations and occupational health professionals.
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References
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