Hearing loss is the third most common chronic physical condition among the general adult population in the United States, affecting more people than diabetes or cancer. And occupational hearing loss, caused mainly by exposure to noise, is the most common work-related illness in the nation. The National Institute for Occupational Safety and Health (NIOSH) estimates that 22 million workers in the U.S. are exposed to hazardous occupational noise. The good news is that occupational hearing loss can be prevented with hearing loss prevention strategies and technology.
We might expect workers in some types of industry to be at a higher risk than others for developing hearing loss. That is exactly what the recently published CDC Occupational Hearing Loss Surveillance Project found. The study, the first to estimate the prevalence of hearing loss by industry sector, focused on noise-exposed workers in the U.S. from 2003 to 2012.
To do so, researchers compared the prevalence of hearing loss within nine U.S. industry sectors from more than 1.4 million worker audiograms. The audiograms came from workers who were exposed to high noise levels, defined as greater than 85 decibels on the A-scale.
The study found a prevalence of 13 percent hearing loss (from mild to complete) among the study population. In terms of the industry sectors studied, mining (17 percent), construction (16 percent), and manufacturing (14 percent) industries showed the highest prevalence of workers with any hearing impairment or moderate to severe hearing impairment. Within manufacturing sub-sectors that include wood product, apparel and machinery manufacturing, workers have occupational hearing loss risks as high as those in mining and construction. In comparison, the public safety sector, which includes police officers and firefighters, showed the lowest prevalence of workers with any hearing loss (7 percent).
Some of the results of the study supported commonplace assumptions about hearing loss in general: The severity of the loss increased with age and a greater percentage of males showed hearing impairment (14 percent) compared to females (7 percent). Another finding was that 2.5 healthy years were lost each year for every 1,000 noise-exposed U.S. workers due to hearing impairment (hearing loss that impacts day-to-day activities).
Another finding was that although occupational hearing loss has been well-established in the construction industry, present noise regulations do not require audiometric testing for construction workers. Without such testing, intervention could be delayed or simply might not happen.
In their conclusion, the authors wrote that early detection of hearing loss by yearly audiometric testing and intervention to prevent further loss – such as training – is critical. The study results support beginning rehabilitation for those at a mild level of hearing impairment to help employees’ quality of life.
According to OSHA, a personal exposure level exceeding 85 dBA requires enrollment of the exposed worker in a hearing conservation program. Companies have the responsibility to assess noise levels and determine whether adequate protections exist to maintain workers' health. Industrial hygienists are challenged to protect employees from noise exposure in all types of work environments, including variable conditions and newly commissioned facilities. In work environments that cannot be remediated to reduce levels below the OSHA action level, personal protective equipment (PPE) is required to protect employees.