Interventions to prevent occupational noise-induced hearing loss

Area of Science:

• Occupational Health
• Audiology
• Public Health Interventions

Background:

• Millions globally are exposed to occupational noise, increasing hearing disorder risk.
• Uncertainty exists regarding the effectiveness of current hearing loss prevention strategies.
• This review is an update of a Cochrane Review first published in 2009.

Purpose of the Study:

• To evaluate non-pharmaceutical interventions for preventing occupational noise exposure or hearing loss.
• To compare interventions against no intervention or alternative methods.

Main Methods:

• Searched multiple databases (CENTRAL, PubMed, Embase, etc.) up to October 2016.
• Included randomized controlled trials (RCT), controlled before-after studies (CBA), and interrupted time-series (ITS).
• Categorized interventions into engineering controls, administrative controls, personal hearing protection devices, and hearing surveillance.

Main Results:

• Stricter legislation in mining reduced noise exposure by approximately 4.5 dB(A).
• Personal hearing protection devices generally reduced noise exposure by about 20 dB(A), with proper insertion training improving attenuation.
• Hearing loss prevention programs (HLPPs) showed very low-quality evidence that better use of hearing protection devices reduced hearing loss risk, but other components lacked similar effect.

Conclusions:

• Very low-quality evidence suggests stricter legislation can reduce workplace noise levels.
• Moderate-quality evidence indicates proper earplug insertion training reduces noise exposure short-term.
• Further research is crucial as conclusive evidence on the effectiveness of many hearing loss prevention interventions is lacking.