Twenty-three percent of workers were exposed to unsafe levels of noise experience hearing loss, found the study.

If that doesn’t sound bad, keep in mind that only 7 percent of those who do not report working in loud conditions similarly report hearing loss.

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The data isn’t at all new--it comes from 2007. But it was only recently examined as part of a report examining potential solutions to widespread ear damage among U.S. workers.

In addition to urging employers and workers alike have to take steps to reduce their exposure to noise, the agency suggests stronger regulations may be necessary to protect employees in typically noisy work environments, such as manufacturing and construction.

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“Hearing loss can greatly impact a workers’ overall health and well-being,” said NIOSH Director John in a statement last week. “A study of the prevalence of hearing conditions among the overall U.S. adult population and among noise-exposed and non-noise-exposed workers gives a clearer understanding of where improved strategies for prevention of hearing loss are needed. Hazardous levels of occupational noise exposure and environmental noise exposure both need to be avoided.”

Hearing loss is a bummer for a number of reasons, including that it puts workers who already work in accident-prone environments, such as construction sites, at greater risk of injury because they miss out on crucial warning sounds.