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NOISE MONITORING Protecting Workers From an Invisible Danger Hearing protection in the workplace is critical in not only preserving workers’ hearing, but in protecting them from larger safety risks. How can companies prevent hearing loss? BY TIM TURNEY Nearly 60 percent of former construction workers suffer from hearing loss, research by the Center for Construction Research and Training has found1. Noise- induced hearing loss (NIHL) is preventable, but the effect is permanent, resulting in life-changing injuries that can seriously impair a worker’s quality of life and increase risk in the workplace. Despite having a duty to protect workers, employers have no obligation to test workers’ hearing in the construction sector, even if noise exposure levels exceed the Occupational Safety and Health Administration’s (OSHA) Permissible Exposure Limit (PEL). So hearing loss is rarely recognized as an ‘occupational disease’ in construction. The Bureau of Labor Statistics (BLS) reports that hearing loss is underreported, and hearing loss data for construction is not comparable with data for general industry. However, the repercussions if employers do not seriously consider the auditory welfare of their workforce can be significant. OSHA estimates that employers spend $242 million annually on workers’ compensation for hearing loss disability2. Despite the risk of irreversible damage to health, one-third of noise-exposed workers report not wearing hearing protection3. Although hearing protection is a ‘first aid’ measure until it is possible to reduce noise exposure to a safer level through changes to the tools, equipment and schedules used, knowledge of its application can dramatically increase its effectiveness. Identifying Workers Most at Risk Any sound over 85 decibels(dB) can damage hearing, meaning the operation of concrete mixers, forklifts, jackhammers, nail guns and masonry drills all pose a permanent risk to worker health if effective control measures are not put in place. A noise survey can help employers determine which employees are at risk. The survey should list employees and their exposure, then compare exposure to the maximum PEL. In OSHA regulations, hearing protection should be available to employees exposed to noise dose levels above 85dB(A). The noise dose is based on the sound exposure level and duration. For each increase 5 dB in noise levels, the duration of the exposure should be cut in half. Noise monitoring provides accurate insights into the noise levels of a workplace, helping businesses identify at-risk employees and ensure they adhere to OSHA regulations. However, professionals undertaking the monitoring should be trained and prepared with the right equipment as minor errors in noise level estimates can lead to major errors in exposure calculations. Two pieces of equipment that can be used for the assessment are the sound level meter, primarily designed as a hand-held device used by an operator, and the noise dosimeter, which a staff member wears for their working shift. A sound level meter is an ideal solution for measuring the overall noise level of a task, piece of machinery, or area. On the other hand, dosimeters are best for Africa Studio/Shutterstock.com 14 Occupational Health & Safety | SEPTEMBER 2023 www.ohsonline.com personal noise measurements where it is difficult or unsafe to get close to employees with a sound-level meter because dosimeters are smaller and body-mounted. For example, a dosimeter would be ideal for truck drivers exposed to many different noise levels and irregular working patterns. If an assessment establishes that noise levels pose a risk to workers, hearing protection should be supplied immediately while other more permanent solutions are implemented. A Better Approach to Selecting Hearing Protection The National Institute for Occupational Safety and Health has published three methods for calculating the attenuation of hearing protectors. However, making sure people wear the protector for the entirety of their shift is essential to ensure real- world protection. Employers can take a proactive approach to encourage all-day wear by considering comfort, communication, the environment, the individual, and the relationship with other personal protective equipment (PPE). Removing PPE, even for short periods, has a significant effect on exposure. Therefore, it is crucial that hearing protection is comfortable to increase worker acceptance and support the likelihood of all-day wear. Employers should avoid a ‘one size fits all’ approach to hearing protection because the shape and size of the ear canal varies from person to person. A protector that fits well for one employee may overprotect some workers or be uncomfortable for others. OSHA recommends having a suitable selection of hearing protection available so that employees can make a choice that best supports their individual needs. The interaction of hearing protection with other PPE is also a significant factor. For example, an employee wearing prescription or safety glasses will not obtain an adequate fit from a standard earmuff, so plugs or semi-inserts may be more suitable. In working environments where hard hats are worn regularly, a hard hat with built-in hearing defenders should be considered.