Page 87 - OHS, October 2021

may start to damage hearing and levels above 120 dB could cause immediate harm.
ThThe decibel level, the distance between a person and the source of the noise, and the amount of time they are exposed can all result in a risk for hearing loss. OSHA has set a legal limit on the amount of noise someone can be exposed to in the workplace. These limits are calculated based on a worker’s time-weighted average throughout an eight-hour day. OSHA’s permissible exposure limit (PEL) is 90 dB for all workers for an eight-hour day. The OSHA standard uses a 5 dB exchange rate, meaning if the decibel level is increased by 5 dB, the amount of time a person can be exposed to that level is reduced by 50 percent. For example, a construction worker can be exposed to 90 dB of noise for eight hours but 95 dB for only four hours.
Industry Regulations
Workplace noise is sometimes referred to as a “stealth, long-term hazard” because hearing loss occurs slowly, in a painless, gradual process. In a study done by the CDC, 51 percent of construction workers have been exposed to hazardous noise levels. Of those workers, 31 percent reported not wearing hearing protection. High decibel levels damage the cells and membranes in the inner ear. Repeated exposure will overwork those cells, causing them to die and result in hearing loss that surgery cannot fix. While hearing aids may help, they do not restore hearing back to normal. NIOSH estimates that 30 million workers are exposed to noise levels high enough to cause irreversible hearing loss.
When decibel levels are at or above 85 dB over an average of eight working hours, OSHA’s Noise Standard requires employers to make hearing protection available to all employees and to implement a hearing conservation program. According to OSHA, these programs “strive to prevent initial occupational hearing loss, preserve and protect remaining hearing and equip workers with the knowledge and hearing protection devices necessary to safeguard themselves.”
With the decrease of even a few decibels, the risk for noise- induced hearing loss is reduced. OSHA recommends three methods for controlling decibel levels in order to lessen the hazardous noise exposure and prevent hearing loss:
Engineering Controls. With engineering controls modifying or replacing equipment, you can make physical changes at either the source of the noise or along the path of noise transmission to reduce the decibel level a worker experiences. This could be as simple as lubricating a squeaking bearing or as vigilant as completely enclosing and isolating the noise source.
Administrative Controls. These changes in the workplace can reduce or eliminate the worker’s exposure to the noise, such as limiting the amount of time a person spends at the noise source or even providing a quiet environment to give time for a worker’s ears to rest between exposures.
Hearing Protection Devices (HPDs). HPDs are active or passive ear protection devices worn in or over the ears, such as ear plugs or ear muffs, to reduce the decibel exposure and protect against hearing loss
One Size Does Not Fit All
Engineering and administrative controls can take time or are not feasible to implement, making HPDs a necessity to prevent
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Ask any construction worker who now has difficulty hearing what they should have done differently, and the majority will agree they should have worn hearing protection before the damage was done.
hearing damage. However, historically, HPDs have been less than desirable for a construction worker to wear. Comfort and convenience are common complaints. Ear plugs can easily get misplaced or dirty and ear muffs can be difficult to wear with a hard hat. PPE has seen little innovation through the years, but some companies, such as Milwaukee Tool, are working to challenge the status quo.
According to company research, comfort and accessibility are two areas that hearing protection could improve on. Ear plugs are often considered an easy choice for construction workers because they are disposable and do not impact other PPE they may also have to wear.
There are three critical things to consider when selecting the proper ear plug. The first is the size of the ear canal opening to determine which size of ear plug is best. Next is to check the shape of the ear canal as different materials may be more comfortable depending on the user’s ear canal shape. Lastly, determine how easy it is to insert the ear plug. To ensure those wearing hearing protection have sufficiently reduced the amount of noise entering their ears, OSHA rates ear plugs using a Noise Reduction Rating (NRR). This unit of measurement is used to determine the effectiveness of hearing protection to decrease sound exposure. The higher the NRR number associated with a hearing protector, the greater the potential for noise reduction. Milwaukee’s Banded Ear Plugs are rated to an NRR of 26 dB. Its Ear Plugs are NRR 32 and its Reusable Corded Ear Plugs are NRR 26.
The Last Word
Hearing loss is one of the most common work-related illnesses in the United States. Because hearing loss occurs over time, it can easily go undetected until it is too late, and the irreversible damage to the ear has already been done. The tasks needed to get done on a jobsite can produce hazardous decibel levels, but taking control of the noise on the jobsite and proper use of HPDs, exposure to these noise levels can decrease a construction worker’s risk of noise-induced hearing loss.
Zach Richman is the Group Product Manager at Milwaukee Tool. OCTOBER 2021 | Occupational Health & Safety 83