Trends in ... Hearing protection

​Protect against this common occupational injury

By Tracy Haas, editorial assistant

Hearing conservation experts say a variety of new technology is available to help protect workers.

“An exciting technology, called Field Attenuation Estimation Systems, enables quick measurements to learn how well an earplug blocks sound while the plug is in the ear of the worker,” said Laurie Wells, senior acoustics specialist at St. Paul, MN-based 3M, Personal Safety Division. “The information gained from fit-testing can be used to ensure that the worker is getting adequate protection from a given hearing protector, by quantifying the noise reduction and calculating a personal attenuation rating.” If the personal attenuation rating is too low, she added, the worker can be taught better fitting techniques or can choose another device that works better.

Robert M. Ghent Jr., research audiologist, manager of the San Diego-based Howard Leight Acoustical Testing Laboratory for Honeywell Safety Products, spoke of workers having stereo microphones for each ear cup of an electric earmuff. He said the microphones are important for preserving localization cues for both ears. “This helps the wearer maintain situational awareness and may improve the ability to hear noise in some cases. The limiting circuitry usually works with all audio signals – radios, entertainment devices, built-in microphones – but is particularly useful when impact noise is present, keeping high-noise peaks from being amplified to dangerously high levels by the communication’s circuitry,” Ghent said.

Another technology on the market is no-roll foam earplugs. The earplugs feature a “multi-curved stem design that allows wearers to achieve a custom fit for each individual ear canal (since no two ear canals are alike) with just a push and a twist,” said Lance Watkins, director of marketing for Moldex-Metric Inc. in Culver City, CA.

Avoiding misuse

The Centers for Disease Control and Prevention lists occupational hearing loss as the most common work-related injury in the United States, and misusing or not using hearing protection continues to be a main contributor to this problem.

Wells cites multiple mistakes workers make when it comes to using hearing protection, including wearing earmuffs over hats, not inserting an earplug deeply enough to properly seal the ear canal and using worn-out equipment.

“We can offer people tools, but if they don’t want to use them or don’t know how to use them, then clearly, they won’t be successful,” Wells said. “Teaching people the value of their hearing puts the emphasis on protecting something that is personal, and is likely to motivate people to pay more attention to taking care of their hearing.”

Watkins agrees that teaching workers about hearing protection is paramount. “Through constant focus and training on proper insertion and fit, better comfort in wearing earplugs can be achieved, for better compliance levels and less hearing loss/injury,” he said.

Compiled with the assistance of the International Safety Equipment Association

Applicable standard

OSHA standard for occupational noise exposure, 29 C FR 1910.95

This standard states that protection against noise exposure effects will be provided when employees are exposed to 8-hour time-weighted average noise levels of 85 dB or above. Hearing protection must be worn by all workers exposed to a TWA of 90 dB(A) and above. Also, hearing protection must be provided at no cost. Employees shall be given the opportunity to select hearing protectors from a variety of suitable hearing protectors.

Coming next month…Instruments/monitors