Introduction
Occupational noise is an unavoidable aspect of many workplaces, from construction sites to manufacturing floors. However, prolonged exposure to high noise levels can have serious health consequences, including hearing loss, increased stress, and reduced productivity.
Occupational Hearing Loss
Occupational Hearing Loss (OHL) can occur when workers are exposed to loud noise or ototoxic chemicals. Ototoxic chemicals are substances that can damage the auditory system, potentially causing hearing loss or balance problems. These chemicals can enter the body through ingestion, inhalation, or skin absorption and travel to the inner ear through the bloodstream. Once in the inner ear, they can damage the hair cells, the cochlea, or the auditory nerve.
Noise is considered hazardous when it reaches 85 decibels (dB) or higher, or if a person must raise their voice to speak to someone 3 feet away.
There are a few symptoms that may indicate OHL, such as:
- Gradual hearing loss
- Tinnitus (ringing in the ears)
- Muffled or distorted sounds
- And, difficulty understanding conversations in noisy environments
Preventing Hearing Loss
Occupational hearing loss is preventable. You can reduce your chances of hearing loss by:
- Wearing earplugs or earmuffs
- Using caution when working with ototoxic chemicals
- Following workplace safety regulations
- Monitoring your hearing regularly
- And, using noise dosimeters to measure sound decibels
Additionally, employers can implement administrative and engineering controls to reduce or eliminate the risk of occupational hearing loss.
Noise Levels and Exposure Times
OSHA allows 8 hours of exposure to 90 dBA but only 2 hours of exposure to 100 dBA sound levels. NIOSH recommends limiting the 8 hour exposure to less than 85 dBA and less than 15 minutes of exposure to 100 dBA.
OSHA also provides recommended exposure times based on different noise levels, including:
- 16 hours of 85 dB
- 8 hours of 90 dB
- 4 hours of 95 dB
- 2 hours of 100 dB
- 1 hour of 105 dB
- 30 minutes of 110 dB
- And, 15 minutes or less of 115 dB
Hearing Protection
When noise levels in the workplace are at or exceed the allowable exposure time, hearing protection is required. OSHA mandates that employers make hearing protection available to employees when exposed to an 8-hour time-weighted average of 85 dB or greater. However, hearing protection is required when noise levels are at or above 90 dB.
There are a few options for hearing protection, including:
- Disposable foam plugs
- Molded earplugs
- Noise-cancelling earplugs or earmuff
- And, earmuffs
Note: Earplugs and earmuffs can be worn at the same time for added protection.
To determine the right type of hearing protection to use, use the Noise Reduction Rating (NRR) on the device and reduce the rated dB level from the allowable exposure time.
Conclusion
Managing noise in the workplace is crucial for protecting workers’ hearing and overall well-being. By understanding the risks, implementing noise control measures, and ensuring proper protective equipment is used, employers can create a safer, healthier work environment.