Hearing conservation: Listen up
Safety pros can take steps to protect workers from occupational hearing loss
UPDATE: This article was updated on March 10 to clarify that OSHA’s Occupational Noise Exposure Standard sets a permissible exposure limit of 90 dBA for an eight-hour period, and that for every 5 dBA increase, workers should cut their maximum exposure time in half. The original article stated OSHA set a boundary of 85 dBA, and that workers are advised to cut maximum exposure time in half for every 3 dBA increase. The 3 dBA increase is a NIOSH recommendation – not part of the OSHA standard.
- OSHA’s hearing conservation program sets noise limits for workers at an average of 85 decibels during an eight-hour period. For every increase of 3 decibels, cut the exposure time in half.
- In addition to providing hearing protection for workers, organizations may establish engineering and administrative controls such as buying quieter machines.
- Organizations can empower workers by providing them with sound-level meters and encouraging them to be part of the solution to reduce noise.
Imagine a massive rock – bigger than a house. Now, imagine being part of a work crew that has to blast that rock out of the ground and into countless pieces of tiny, crushed rock. Imagine the noise.
“It’s very hard to turn big rocks into little rocks quietly,” said Kelly Bailey, a 36½-year veteran of Birmingham, AL-based Vulcan Materials Co.
Although noise exists, so do solutions. At Vulcan, Bailey has helped the organization garner national recognition for its efforts to prevent occupational hearing loss. As the company’s director of safety, health and environment, Bailey traveled to St. Petersburg, FL, in 2013 to accept the NIOSH Safe-In-Sound Excellence in Hearing Loss Prevention Award.
Bailey’s message to fellow safety professionals is simple: By taking steps to protect your workers from hearing loss, you make your organization safer, stronger and more satisfied.
“Noise is certainly a hazard that you want to have under control,” said Bailey, whose organization employs about 7,000 workers in 19 states, the District of Columbia, the Bahamas and Mexico. “That’s why the exposure monitoring program is so important. You need an army to address it. We try to get as many levels of our employment involved in the monitoring aspect and the controlling aspect.”
Defining the issue
According to OSHA, approximately 30 million workers are exposed to hazardous noise every year in the United States. Thousands of those workers sustain hearing loss because of noise exposure. The Bureau of Labor Statistics estimates that, since 2004, about 125,000 U.S. workers have reported “significant, permanent hearing loss” associated with their jobs.
Temporary hearing loss because of short-term noise exposure may be addressed with proper rest, but permanent hearing loss can’t be reversed. People who lose hearing often deal with psychological and social effects such as frustration, feelings of isolation and stress. Ramifications extend into the workplace, where a worker with hearing issues might not recognize an alarm or a warning from a colleague.
“Hearing loss itself is considered a health issue,” said Dr. Amanda Azman, a NIOSH research audiologist with the Pittsburgh Mining Research Division. “It’s a negative health outcome of certain activities, but it leads to a safety issue in the workplace. That’s why it’s important to ensure that people can maintain the hearing that they have, not to lose any more, and for those who are younger and maybe haven’t been in the industry for so long, promote to them how important it is to protect their hearing.”
How loud is too loud?
OSHA’s permissible exposure limit for noise is 90 dBA for an eight-hour period. For every 5 dBA increase, the agency’s Occupational Noise Exposure Standard calls for workers to cut their maximum exposure time in half. For example, 95 decibels is safe for up to four hours, 100 decibels is safe for up to two hours, and so on.
Additionally, the standard calls for general-industry employers to create a hearing conservation program when workers are exposed to 85 dBA or higher for an eight-hour period.
NIOSH and other leading experts recommend cutting workers’ exposure time in half for every 3 dBA increase, as opposed to the 5 dBA marker within OSHA’s standard. For example, 88 decibels is safe for up to four hours, and 91 decibels is safe for up to two hours.
Baseline and annual audiograms may help participants in a hearing conservation program determine whether workers are avoiding hearing loss. If a worker shows a change in hearing test results – described by experts as a “standard threshold shift” – the employer is required to fit or refit the worker for hearing protection, train the worker on proper use, and ensure the worker wears the protection.
OSHA offers the following signs that a workplace might be too noisy:
- Workers hear ringing or humming in their ears at the end of the workday.
- A worker must shout to be heard by another worker an arm’s length away.
- Workers notice temporary hearing loss at any point when leaving work.
“There are many things that individual companies or manufacturers can do,” Azman said. “Almost all mining companies should have some sort of hearing conservation program. The problem is that they don’t necessarily follow all of the components.
“The biggest item that’s sometimes missed is doing the area noise monitoring regularly, and first looking at potential engineering and administrative controls for noise issues before handing out hearing protection. Not to say that hearing protection is bad or doesn’t work – it’s actually quite good – but the first two steps in the Hierarchy of Controls – engineering and administrative controls – are a better solution. It’s more widespread. It’s not reliant on one person wearing one set of hearing protection.”
NIOSH leads a “Buy Quiet” inititaive that encourages the use of quieter, more modern machines.
“Even if you can reduce the noise coming off the machine by 3 decibels, that’s a big difference in the amount of noise that worker is being exposed to,” Azman said. “It makes a big difference in the amount of time they can work around a machine. It makes a difference in the type of hearing protection they may need based on the [noise reduction rating]. So 3 decibels might not sound like a lot, but it actually is.
“One other thing is machine maintenance. In anything where there is large equipment, when maintenance is bad, often the machine starts to rattle and shake and bump in ways that don’t happen if they’re in good working order. If you have an old machine that is noisy, it doesn’t mean nothing can be done.”
Vulcan began conducting audiometric tests in 1976 – years before the practice was required by OSHA and the Mine Safety and Health Administration. The tradition continues 40 years later at the organization, which supplies workers with sound-level meters and encourages them to test noise levels. The devices, which cost about $80, empower workers to protect their hearing, Bailey said.
“We have hourly employees that are doing sound-level meter testing, and if they find a piece of equipment, immediately they can go after it themselves – before the safety and health guy may even know it’s happening,” Bailey said. “We have a lot of people contributing to reducing noise.”
New workers at Vulcan quickly learn about the importance of testing noise levels.
“When we acquire a smaller, mom-and-pop operation, they weren’t getting this kind of treatment [before the acquisition],” Bailey said. “At first, you do your audiometric testing, and everyone is a little bit apprehensive about it. But they soon learn that it’s part of the Vulcan way, the Vulcan culture. You’re not going to be in trouble for having a high noise. You’re going to be involved in the resolution of that issue.”
The mining sector has the highest prevalence of hazardous noise exposure of any industry, according to NIOSH. Hearing loss is a lagging indicator, and it could take years before experts know whether current efforts are succeeding. Another challenge: Separating occupational noise from recreational noise. Safety professionals can help by reminding workers to protect their hearing off the job as well, particularly when it comes to hobbies such as using power tools, listening to loud music and driving all-terrain vehicles.
Azman said she is optimistic that long-term data will show progress in hearing protection.
“One of the good things we’re seeing is an improvement in recognition that noise is a hazard, that hearing loss is a bad thing, and that you don’t have to accept that it’s just a condition of your job,” Azman said. “We’re seeing an improvement in that recognition, where I don’t think maybe 15 years ago noise and hearing loss was really recognized as such a life-changing issue. “People don’t lose their lives from noise, and that’s why sometimes it’s maybe not recognized as much as the other hazards that exist. But it changes your life.”