Fifteen per cent of workers who have been exposed to occupational noise at some point in their careers have tinnitus, a debilitating often high-pitched ringing in the ears, found a new study from the National Institute for Occupational Safety and Health (NIOSH). This is compared to five per cent of workers who have never been exposed to occupational noise.
“Tinnitus is prevalent and very common; especially common among noise-exposed workers,” says Elizabeth Masterson, lead author and epidemiologist at NIOSH in Cincinnati. “Hearing loss prevention and early detection and intervention to stop the hearing loss is critical.”
Tinnitus, which can be constant or intermittent, is the term used to describe noises or sounds heard by an individual that do not come from an external source. While ringing is the most common, it can also be described as buzzing, hissing, pulsing, whistling or roaring. Tinnitus can be very mild in loudness and only noticeable in a quiet room or it can become extremely loud and annoying to the point where the sufferer hears nothing else.
Health and safety managers are likely unaware of how big the problem really is within their own workforce, says Carolyn Wisdom, industrial hygienist and owner of Wisdom Consultants in Edmonton.
“It could be huge… Health hazards are always minimized in the workplace. When I go in to do a noise survey, it’s always worse than people think,” she says. “A lot of businesses have safety professionals but they don’t have anyone to look after health issues, and the safety professionals are not trained in this.”
And as with any other form of occupational hearing loss, workers can file a workers’ compensation claim for tinnitus.
Workers in agriculture, forestry, fishing and hunting have a significantly higher risk of tinnitus, found the NIOSH study, with 13 per cent of workers in this sector suffering from the condition. Nearly one-half (43 per cent) of workers in this industry are exposed to hazardous noise on the job.
In agriculture, farmers need to contend with loud sounds from machinery and animals. They are also not regulated by health and safety regulations — although this is changing in Alberta and P.E.I.
“It was always thought to be a family affair. Many believed the government had no place on farms,” says Wisdom. “There was no education and nobody coming to let them know about this hazard or put any emphasis on it.”
In forestry, workers are cutting down trees with chainsaws and other equipment, which generate tremendous amounts of noise. The equipment also generates carbon monoxide, which further increases the risk of hearing loss as it is an ototoxic chemical. Ototoxic chemicals include solvents, heavy metals (such as lead and mercury) and asphyxiants (carbon monoxide).
“These chemicals can either cause the hearing problem or they can make your ear more susceptible to noise. In which case, in concert with noise, you are more likely to have a hearing loss or have tinnitus,” says Masterson.
Some fishing occupations also have high noise exposure, such as working near the engine or boiler room. The wind and other noises on deck can be very loud as well, says Masterson. Additionally, these workers may not be wearing hearing protection as the safety culture may not be as strong as some other industries.
In commercial hunting, which includes the exploitation and management of game preserves, workers are exposed to gunshots, which can lead to tinnitus.
“Acute but loud noises can cause tinnitus, just from one experience,” says Michael Chrostowski, president and CEO of Sound Options Tinnitus Treatments in Toronto. “I have met people who have been to a firing range or who used a fire arm and didn’t take any steps to protect their hearing and that one incident caused permanent tinnitus.”
Manufacturing also has a significantly higher risk of tinnitus, found the NIOSH study, with 11 per cent of workers in this sector having the condition. The manufacturing industries that typically have a higher risk are metal, wood products, apparel, petroleum and coal products and machinery.
The report cited other research that found 70 per cent of drop-forge operators and 22 per cent of meat-packers had tinnitus.
“When you have this machine coming down and hitting metal as it’s hot, when it hits, that’s like 145 decibles — that’s about what a gun shot is,” she says, noting manufacturing workers can be exposed to both constant noise and impulse noise (a very quick, loud sound).
Architects and engineers also have a significantly higher risk of tinnitus, found the study.
“They are out doing reviews of the sites and giving advice, but they are probably not wearing hearing protection,” says Wisdom. “They think ‘I am only going there for an hour, it won’t be a problem.’ But without hearing protection, people don’t understand they don’t need to be out there long to be overexposed.”
It’s likely architects and engineers do not have the same training or awareness in terms of noise exposure and hearing protection as the primary workers on the sites they are visiting, says Chrostowski.
“They might not know how to use their hearing protection correctly. They may have fewer incidents but it may be more risky for them because they are not as trained as other workers.”
While constant noise, impulse sounds and ototoxic chemicals can contribute to the development of tinnitus, trauma to the head or neck, such as concussion or whiplash, can also cause long-lasting tinnitus, according to the Canadian Academy of Audiology.
Tinnitus can potentially increase the risk of accidents, found the NIOSH study. The constant ringing in the ears can be very distracting on the job and prevent workers from hearing important warning sounds or communications.
“If you are on the job and you have to pay attention to important cues, the forklift is backing up or you are in a mine and certain warning bells that let you know the machine — which could pin you to the wall and kill you — is moving and you are hearing this rushing in your ears, it can be a distraction,” says Masterson.
But the biggest issue with tinnitus is it affects sleep and concentration. This means general safety and effectiveness is hampered.
“If you are coming to the job fatigued, that can be a problem for your level of alertness. You’re missing cues, you’re basically just going through the motions,” says Masterson. “If you are driving a vehicle as part of your job, dangerous equipment as part of your job or if you are in a job where communication is absolutely critical — police, fire — you could be missing communication because you are really tired and not alert.”
Tinnitus is also associated with depression and anxiety, noted the report. There have even been a few suicides due to extreme tinnitus, says Masterson.
“As hearing loss worsens it really has a detrimental effect on the communications you have with others… You have to keep asking people to repeat themselves; you get frustrated, they get frustrated, the conversations with important people in your life become shorter because it’s a frustrating experience,” she says. “You lose the volume and quality of the sounds you want to hear: music, TV, a child’s voice. You lose enjoyment.”
The lack of public awareness around tinnitus also contributes to mental health issues, says Chrostowski, as individuals suffering with the condition feel as though no one understands what they are going through.
Occupational hearing loss is entirely preventable and the first thing employers need to do is measure the noise in their workplace, says Wisdom.
“They need to measure their noise sources, tools and equipment as to levels being generated — and then measure employee exposure with noise dosimetry,” she says. “They need to determine what their noise levels are — they can’t fix something if they don’t know they have a hazard.”
The next step is to develop a noise conservation program, which will include many elements, such as methods of noise control. For this, employers need to follow the hierarchy of controls and start with looking for ways to eliminate the noise. One way to do this is by properly maintaining and lubricating tools.
The next step is substitution. For example, there are some tools on the market with low noise levels, so the purchasing department needs to know to look for ones with reduced decibel ratings, says Wisdom.
Next is engineering controls. Encasing the noise is one example. Employers can put a noisy machine in a room that’s soundproof, so only the person who has to go in there to work that machine is exposed.
Administrative controls, such as work scheduling, are the next best thing.
“See if you can split the noise,” says Masterson. “Instead of one in there for eight hours, have two people go in — one for four and another person for four. We just reduced the exposure for that person by half.”
The last step is hearing protection, which unfortunately is often the go-to for employers, says Wisdom.
“They just throw earplugs at people, with no training on how to put them in. Hearing protection should always be the last resort, but it’s actually the first resort in many workplaces,” she says.
Employers should make sure to fit test all workers for their hearing protection and teach them how to use it properly. Supervisors and managers need make sure they are continually enforcing the use of hearing protection, says Chrostowski.
A hearing conservation program should also outline the requirements for audiometric testing and the maintenance of test records. Workers should undergo annual testing so they can know if hearing loss is occurring, says Wisdom.
A plan needs to be in place to educate workers on the hazards of exposure to excess noise.
“It’s important to educate workers on what tinnitus is, what it sounds like and know what their risks are,” says Chrostowski. “With hearing loss, everyone has an idea of what it is and it’s easy to assume it’s not a big deal or they won’t have issues. A lot of us are guilty for taking our hearing for granted.”
One effective education tool is to play an example of what tinnitus sounds like (which is easy to find on YouTube).
For workers currently suffering from tinnitus, health and safety managers need to be even more vigilant with hearing protection, so they prevent these workers from losing any more hearing, says Chrostowski. If possible, the noise exposure should be reduced for workers with tinnitus or eliminated for those with severe cases.
“Treat it as if you would a back injury. You wouldn’t ask a person with a back injury to lift heavy loads, and you shouldn’t ask a person with tinnitus to be exposed to high noise levels,” says Wisdom.
The workplace can also put in place non-verbal communication techniques (hand signals) as well as visual cues (flashing lights), so there is less dependence on hearing for these workers.
The good news is tinnitus can be managed and reduced, says Chrostowski. There are various treatment options available for tinnitus on which employers can provide information. These include tinnitus sound therapies that are available through some hearing clinics or tinnitus retraining therapy provided by trained hearing professionals.
“With the right therapies and support from employers, employees with tinnitus can regain a sense of control and quality of life. Tinnitus can affect a person’s life in many ways, but what makes it worse is feeling that nothing can be done and nobody understands,” says Chrostowski. “Employers have the opportunity and means to address these issues… and in so doing they will improve the lives and productivity of employees with tinnitus.”
This article originally appeared in the October/November 2016 issue of COS.
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