As a hearing conservationist, National Hearing Conservation Association (NHCA) President Theresa Schulz has heard more than her share of heartbreaking stories from workers suffering from hearing loss. But nothing prepared her for the compelling story she heard during a presentation at an annual NHCA conference almost a decade ago.
The presenter was a former construction worker in his mid-forties who had significant hearing loss. He started working in construction in his teens, often using jackhammers without wearing hearing protection. He explained during the presentation that a few years ago his sister, with whom he had a strained relationship, was diagnosed with terminal breast cancer.
As she was dying in the hospital, the two tried to mend the rifts in their relationship. She tried to tell him something, but because she was surrounded by the buzzing sounds of medical equipment, he wasn't able to hear what she was trying to say.
According to Schulz, the presenter told the audience that not hearing her last words haunts him. “When people tell me you just hear what you want to hear, it makes me angry, because I never wanted to hear anything more than that in my whole life,” Schulz recalls him saying.
Examples like this point to how devastating hearing loss can be for a worker, not just because it impacts his or her actual ability to hear, but also because it can affect personal and emotional well-being.
While noise exposure is a pervasive problem in the workplace - it is estimated that the number of workers who suffer from noise-induced hearing loss is in the tens of millions - it is entirely preventable.
Twenty years ago, OSHA implemented detailed noise exposure regulations (29 CFR 1919.95) and since then, many employers and safety professionals diligently have monitored noise levels at work sites, posted warning signs, purchased earplugs and routinely testing employees' hearing. Yet noise-induced hearing loss continues to occur at an alarming rate.
The Start of a Movement
Forty years ago, well before OSHA implemented its regulations on hearing protections, people thought that losing their hearing as they got older was a fact of life. They were not aware that occupational noise exposure was the cause of hearing loss for many victims.
Richard Danielson, an associate professor at the Baylor College of Medicine and a consultant for NASA Johnson Space Center, says a study conducted in the 1960s on the Mabaan tribe in Sudan challenged that assumption. The study found that the primitive tribal elders, who had no access to any form of man-made technology that could produce noise to harm their hearing, had the same level of hearing as the teenagers of the same tribe.
“This proved that you didn't have to lose your hearing just because you got older,” Danielson says.
Although the findings triggered what Danielson calls the “birth of the hearing conservation” movement, noise-induced hearing loss is considered a troubling occupational hazard, with the National Institute for Occupational Safety and Health (NIOSH) labeling it one of the 10 most serious occupational illnesses and injuries dealt with today. Still, says Elliott Berger, senior scientist for auditory research at Aearo Corp., occupational hearing loss does not receive the same attention as other serious workplace illnesses and injuries.
“Hearing loss is an injury that you can't immediately recognize,” says Berger. “In the safety industry, we are so accustomed to things that draw blood or that cause immediate injury, we rush to give those immediate attention, and that makes hearing loss a low priority in many cases.”
Physical and Emotional Impacts
Berger warns that while the physical signs of hearing loss aren't as obvious as fall-related injuries, for example, the impact is substantial. He says that some evidence suggests that people who have had chronic noise exposure above 85 decibels (dBA) experience higher serum cortisol levels in blood (a sign of stress), increased blood pressure and accompanying headaches, insomnia and irritability. Workers who wore hearing protection showed decreased levels of cortisol, which reduced their levels of fatigue and irritability.
Other hearing conservation experts note that many people believe the most profound physical impact of hearing-related injuries is losing the ability to hear. Schulz explains that noise-induced hearing loss also can cause people to suffer from tinnitus or “ringing in the ears.” People with tinnitus hear sounds that exist only in their own ears - ringing, whistling, buzzing or clicking, for example.
“Tinnitus can be, for many, even worse than the hearing loss itself, as the sounds can become distressing and in many cases, they never go away,” Schulz says.
Tinnitus is only one of many symptoms of noise-induced hearing loss. Other symptoms include a gradual decrease in sound or a growing distortion, particularly of speech comprehension. Because hearing loss advances slowly, sufferers may not be aware of the impairment at first. They even may be unconsciously compensating for the loss by reading lips or turning up the radio or television volume, which can be even more frustrating, since the sound will not be as clear and sharp as it was when they had normal hearing.
With hearing loss, the physical impact almost always leads to an emotional effect, Schulz adds. As the vast majority of our interactions are either in person or over the phone, a person who loses his hearing will experience stress when he constantly has to ask others to repeat themselves. This can cause strain among family relationships, and even has been the cause of divorce among some couples, according to Schulz. As a result, individuals with hearing loss often socially alienate themselves from others, Schulz says.
“Helen Keller, who was blind and deaf, had a great quote, which speaks to how much worse a malady it is to be deaf than it is to be blind: ‘Blindness separates us from things, but deafness separates us from people,’” Schulz recalls.
Hearing loss not only can be dangerous for workers experiecing hearing impairment, but for other employees working with them as well. Besides communicating with one another, workers must be able to hear announcements and pages over a public address system, as well as fire and other evacuation alarms or vehicle back-up signals. Equipment operators rely on subtle changes in sound to gauge whether their equipment is running correctly. All of these things can be impacted when one or more employees experience hearing loss.
Ways to Control Noise Exposures
Workers in any field can be exposed to high levels of noise, but there are certain industries - mining, agriculture, construction, manufacturing and utilities, transportation and the military - that run the highest risk of exposing employees to noise-induced hearing loss.
Schulz says many people are under the impression that the first line of defense against hearing loss is to wear hearing protection devices such as earplugs and earmuffs, but that is not the case.
“If you think about this common sense-wise, wouldn't it be easier to just try and make your environment quieter?” she asks.
Brad Witt, director of hearing conservation for Sperian Protection, says eliminating occupational noise through engineering controls should be the company's first line of defense if possible. Certain measures, such as installing “silencers” (mufflers and baffles, for example) on equipment, work by absorbing sound.
“Sometimes, though, it is very difficult to do that, either because it is often times not feasible or technically possible,” Witt notes.
If applying engineering controls to eliminate noise is not possible, limiting the noise exposure or implementing administrative controls is the next best thing. Witt recommends that employers rotate their workers in the production area. For instance, instead of having a worker exposed to occupational noise for 8 hours, employers should have two workers there for 4 hours at a time. In addition, Witt also advises safety managers and supervisors to give workers breaks away from work or production areas, “anything to reduce their exposure time,” he says.
Issues With Hearing Protectors
If administrative controls also are not feasible, hearing protection devices should be utilized to protect workers. Although the number, variety and effectiveness of hearing protection devices have improved since the devices first came out around World War II, workers are not always keen on wearing them.
Issues with comfort, costs and convenience are common complaints workers have when required to wear hearing protection, but according to Witt, the number one reason why workers don't consistently wear protection is that they can't hear what others are saying.
“So even though ear plugs are passed out, workers take them out to talk to their coworkers and it defeats the whole purpose,” Witt points out.
Technological advances in hearing protection have enabled manufacturers to come out with hearing protection that manages sound, rather than just blocking it. For instance, level-dependent earmuffs have microphones mounted on the surface of the earcups, which feed the signal to an amplifying circuit with a built-in limiter. While wearing them at a construction site, for example, a worker would clearly hear warning signals and co-workers' voices, but also be protected from the intermittent noise of power tools or unexpected impact sounds, Witt says.
“In this day and age, there are over 200 hearing protector devices available, and workers can pick or choose which one best meets their needs,” Witt emphasizes.
Changing a Mindset
No matter how effective the device, a hearing protector only works if the wearer uses it as recommended. NIOSH's Senior Research Audiologist Mark Stephenson, Ph.D., says when he goes out to jobs sites, he notices that a majority of people aren't wearing hearing protectors, and says the agency is considering how it can use health communication theory to improve education and training programs on hearing protection.
“You can lead a person to hearing protectors, but you can't get them to wear them,” Stephenson says.
He notes that while an abundance of information about hearing protection often is made available to workers, the trick is to present this information so it sticks and doesn't seem like another job requirement. One of the methods NIOSH has been looking at, Stephenson says, is creating 30-minute training videos that focus on specific needs and that are available in formats that workers can use at home or on their Ipods.
“We want to apply principles of marketing to implement change in workers' behavior towards hearing protection,” Stephenson notes. “They have to believe in the benefits and effectiveness and they have to believe that barriers such as cost, comfort and ability to communicate can be easily overcome.”
Danielson says one way to get workers' attention is “to build it to your audience.” He likes to do this via demonstrations. As a consultant for NASA Johnson Space Center, he deals with professionals - pilots and engineers - who are technologically savvy. Knowing this, he took the opportunity to explain the damaging effects of hearing loss by comparing the complex anatomy of an ear to the motherboard of a computer. He held the motherboard up and explained the 30,000 sensory cells in an ear were organized in a similar fashion to the way a motherboard was set up. Then he went on to demonstrate how the ear looks after it has been routinely exposed to occupational noise without any hearing protection.
“I took a heavy hammer and whacked the motherboard to pieces,” he says. “They jumped out of their chairs!”
This visual demonstration used a comparison workers can identify with, and helped them understand how damaging hearing loss can be.
“You have to make it creative for the audience so they can understand it better,” says Danielson.
Hearing Protection Fit Testing
Another reason why hearing loss is so prevalent among workers is because there is no ideal way to assign a proper earplug or earmuff when accounting for a person's noise exposure, amount of protection required and individual hearing sensitivity. According to Berger, hearing conservationists have attempted to do this using noise reduction ratings (NRR), which are provided by manufacturers in keeping with the EPA's hearing protector labeling regulation. But, according to Berger, “this approach is fraught with error.”
“The numbers are based upon an optimized fitting scenario in a controlled laboratory environment that bears little resemblance to the conditions under which workers wear [hearing protectors] on a daily basis,” he contends.
That's why Berger recommends individual fit testing. According to him, fit testing serves many purposes in a hearing conservation program, but the most important one, he says, is that it can serve as tool to train and motivate employees to wear their hearing protectors.
Fit testing has been available in hearing conservation labs for years, but there are a number of potential systems that could provide solutions and eliminate the incidence of incorrectly worn hearing protectors, Berger explains.
All the hearing protection devices that are available on the market are useless if employers aren't drawing workers' attention to the problem of hearing loss through proper training and motivation, Berger notes. And it's a shame, he says, because hearing loss is one workplace illness is entirely preventable.
“There is no need for noise-induced hearing loss, because a correctly worn hearing protector can virtually solve all noise exposure problems,” he emphasizes. “All you need to do is wear it and wear it right.”