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Sound advice on hearing conservation
The article aims to provide a helpful overview of the requirements, as well as some compliance tips to give your programs a boost, or to help you get one off the ground.
Hearing conservation (29 CFR 1910.95)
More than 10 percent of the
The hearing conservation section of OSHA’s noise exposure standard requires that employers establish “a continuing effective hearing conservation program” if their facility generates high noise levels – that is, levels exceeding 85 decibels (dB) on an eight-hour time-weighted average (TWA).
The noise volume in a typical office is about 70-75 dB. A sander emits about 85 decibels, factory noise is 80-90, and the sound of a pneumatic drill is about 100. By way of comparison, a whisper is about 10 dB and a car horn is 120. It’s estimated that more than 9 million people are exposed to job-related noise levels above 85 dB, most of whom work in manufacturing and utilities.
High noise levels are quite common in workplaces where metal-on-metal impacts occur, such as metal fabrication plants. But food processing, textiles, lumber and wood, and many other industries are also big noisemakers. When assessing the risk of noise-induced hearing loss, it’s essential to consider the exposure duration. Noise levels even as high as 130-140 dB can be harmless if the duration is extremely short and if there are no or few repetitions.
It’s the law!
OSHA says that if employees are regularly exposed to noise levels above 85 dB, they must be required to wear hearing protection devices in areas of high noise. Also, they must be trained in the potential hazards of noise exposure and must be offered a choice of hearing protection devices. The training program must include:
1) information on the effects of noise on hearing;
2) the purposes of hearing protectors, including their advantages and disadvantages, the attenuation provided by various types, and the instructions on their selection, fitting, use and care;
3) the purpose of audiometric testing and an explanation of testing procedures.
Protection measures can include the following:
- reorganizing equipment, facilities and/or tasks to reduce noise levels
- monitoring individual and work-area noise levels and reporting high levels to employees
- testing employee hearing with annual follow-ups
- providing hearing protectors where needed
Noise reduction strategies
Noise can be reduced in a work area through a variety of strategies. Among them:
- separating noisy machinery or operations
- keeping equipment well-maintained and lubricated so it doesn’t rattle or squeak
- replacing worn or loose machine parts
- using substances like wood or plastic instead of metal when possible
- using sound-absorbing acoustical tiles on the floor, ceiling or walls
- considering noise levels during the new equipment purchasing process
- trying to perform noisy maintenance tasks after hours
The standard requires that hearing protectors reduce the noise to no higher than 90 decibels. There are three categories of protectors:
Earmuffs usually provide the greatest amount of protection to the ears. They consist of a headband, ear cups and ear cushions.
Earplugs seal the ear canal and keep noise from getting through to the ear’s delicate parts. There are quite a variety on the market. Some come in standard sizes, while others are custom-fitted to the ear.
Canal caps are soft pads on the ends of a headband, similar to headphones. The caps, which must fit snugly, seal the entrance to the ear canal rather than entering it, as earplugs do. Some particularly noisy environments may call for wearing more than one kind of protector (e.g., plugs and caps or muffs).
Beyond compliance, it just makes sense that a successful program must include the support and involvement of supervisors and top management. They should be especially aware of the reasons for the program, why hearing is so important to preserve, and what happens to the noise-exposed ear when it is unprotected. They should also wear hearing protection themselves in posted areas – not just to set a good example, but to protect their own precious hearing.
Invisible and insidious
Noise, like other occupational health hazards, is insidious. Those with noise-induced hearing loss may not even become aware of the problem until it has reached serious levels, and by that time the loss can be permanent. Noise is also an invisible risk – unlike a solvent or a sharp object, the risk cannot be seen, which leads some employers and employees to underestimate its importance.
In most cases, noise-related hearing loss occurs gradually, starting with a temporary loss that over time can become permanent. An overly noisy environment can have serious effects on a worker’s ability to communicate. Experts say that communicating in noise levels above 85 dB is not satisfactory for the speaker or for the listener. Noise can also mask acoustic warning signals and the sounds of properly functioning equipment. And, it can negatively affect job performance.
While routine tasks are not usually affected, complex tasks are, especially as the noise gets louder. Intermittent, unpredictable noise is especially detrimental to optimal functioning. Some studies have shown that even fairly moderate levels of noise can raise anxiety and increase the risk of antisocial behavior. Although the research is somewhat controversial, there is some evidence of a link between noise exposure and stress diseases such as cardiovascular disorders and ulcers. There’s also plenty of anecdotal evidence that workers are less fatigued, less irritable and sleep better when they’re part of a hearing conservation program. As well, they appear to have fewer accidents and absences.
Train and motivate!
It’s important that hearing conservation training – whether it’s group or individual – instruct but also motivate employees to wear their protection when necessary. Some trainers like to use the metaphor of grass to represent the tiny sensory (or “hair”) cells of the inner ear. Usually, blades of grass will straighten up after they’ve been bent by being walked on. However, if one continues to tread on the same patch day after day, the grass will eventually die, leaving a bare spot. That’s similar to what happens to the ear’s hair cells when assaulted by high-decibel sound.
Employees should be told about the symptoms of noise-induced hearing loss, including persistent tinnitus or ringing in the ears, a sensation of muffled hearing after a work shift, difficulty understanding conversation in groups or noisy surroundings, and the sense that people are mumbling.
Training should extend beyond the formal sessions – supervisors should routinely make sure that ear plugs are inserted correctly, check ear muffs, head bands and cushions, and ask employees about their use and comfort. A simple yet valuable technique for motivating employees is to explain their audiometric test results to them, perhaps comparing a current audiogram to a previous test and comparing it with a “normal” result. If threshold levels are deteriorating, it’s time to remind the worker about fitting and wearing hearing protection.
Supervisors should be sensitive to unusual situations. For example, some workers may be fearful that wearing the protector could make them unable to hear a malfunctioning machine or could compromise their ability to communicate. There are, however, special types of hearing protectors that are especially designed to facilitate communication and thus might be an appropriate solution.
Some employers have found that workers comply better with hearing protection rules when their families are involved. Businesses may choose to provide audiometric tests for spouses and children. This gets people talking about hearing protection on and off the job.
SIDEBAR
Occupational noise exposure checklist (1910.95)
n Engineering and administrative controls are used in areas where noise levels exceed the permissible noise exposure.(b)(1)
n A hearing conservation program has been implemented when noise exposures equal or exceed an eight-hour time-weighted average (c)(1)
n A noise monitoring program has been implemented exposures equal or exceed an eight-hour time-weighted average (d)(1)
n A training program been instituted for all employees who are exposed to noise at or above an eight-hour time weighted average of 85 decibels. ((k)(1)).
n The training program is repeated annually for each employee in the program.((k)(2)).
n Employees are kept informed of the following:
- the effects of noise on hearing ((k)(3)(I));
- the purpose, advantages, disadvantages, selection, use, fitting and care of hearing protectors ((k)(3)(ii));
- the purpose and procedures of audiometric testing ((k)(3)(iii));
- accurate records of employee exposure measurements are maintained (m)(1);
- audiometric test records are retained ((m)(2)).
About the author:
This article provided by TrainingOnline.com, an e-learning division of Business and Legal Reports Inc. and a publisher of quality compliance, training and productivity tools for the workplace. For more information on the company’s range of products and services, visit www.TrainingOnline.com.
