Work & Hearing
Within the structures of the ear, nose and throat are complex and interrelated
mechanisms that allow a person to make sound, hear, maintain balance,
smell, breathe, and swallow. Traditionally, treatment of the ear otology
was associated with that of the eye in medical practice. With the development
of laryngology the study of the throat in the late 19th century, the connection
between the ear and throat became known. Thus the birth of a discipline
Many people associate otolaryngologists with the treatment of ear infections,
hearing loss and sinus problems. Otolaryngology actually encompasses the
treatment of many diverse conditions, including: dizziness, facial plastic
and reconstructive surgery, head and neck cancer, hearing loss, problems
of the larynx and sinus, difficulties swallowing, tumors of the auditory
nerve, and voice production.
When diagnosing ear, nose, and throat disorders, it is important to differentiate
genetic disorders from those due to environmental influences. This is often
difficult as similar clinical features may be produced by different environmental
factors or by different genes or groups
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Expandable foam plugs
These plugs are made of a formable material designed to expand and conform
to the shape of each person's ear canal. Roll the expandable plugs into
a thin, crease-free cylinder. Whether you roll plugs with thumb and fingers
or across your palm doesn't matter. What's critical is the final result—a
smooth tube thin enough so that about half the length will fit easily into
your ear canal. Some individuals, especially women with small ear canals,
have difficulty rolling typical plugs small enough to make them fit. A few
manufacturers now offer a small size expandable plug.
Pre-molded, reusable plugs
Pre-molded plugs are made from silicone, plastic or rubber and are manufactured
as either “one-size-fits-most” or are available in several sizes. Many pre-molded
plugs are available in sizes for small, medium or large ear canals.
A critical tip about pre-molded plugs is that a person may need a different
size plug for each ear. The plugs should seal the ear canal without being
uncomfortable. This takes trial and error of the various sizes. Directions
for fitting each model of pre-molded plug may differ slightly depending
on how many flanges they have and how the tip is shaped. Insert this type
of plug by reaching over your head with one hand to pull up on your ear.
Then use your other hand to insert the plug with a gentle rocking motion
until you have sealed the ear canal.
Advantages of pre-molded plugs are that they are relatively inexpensive,
reusable, washable, convenient to carry, and come in a variety of sizes.
Nearly everyone can find a plug that will be comfortable and effective.
In dirty or dusty environments, you don't need to handle or roll the tips.
Canal caps often resemble earplugs on a flexible plastic or metal band.
The earplug tips of a canal cap may be a formable or pre-molded material.
Some have headbands that can be worn over the head, behind the neck or under
the chin. Newer models have jointed bands increasing the ability to properly
seal the earplug.
The main advantage canal caps offer is convenience. When it's quiet, employees
can leave the band hanging around their necks. They can quickly insert the
plug tips when hazardous noise starts again. Some people find the pressure
from the bands uncomfortable. Not all canal caps have tips that adequately
block all types of noise. Generally, the canal caps tips that resemble stand-alone
earplugs seem to block the most noise.
Earmuffs come in many models designed to fit most people. They work to block
out noise by completely covering the outer ear. Muffs can be "low profile"
with small ear cups or large to hold extra materials for use in extreme
noise. Some muffs also include electronic components to help users communicate
or to block impulsive noises.
Workers who have heavy beards or sideburns or who wear glasses may find
it difficult to get good protection from earmuffs. The hair and the temples
of the glasses break the seal that the earmuff cushions make around the
ear. For these workers, earplugs are best. Other potential drawbacks of
earmuffs are that some people feel they can be hot and heavy in some environments.
Manufacturers are receptive to comments from hearing protection users. This
has led to the development of new devices that are hybrids of the traditional
types of hearing protectors. Because many people like the comfort of foam
plugs, but don't want to roll them in dirty environments, a plug is now
available that is essentially a foam tip on a stem. You insert this plug
much like a pre-molded plug without rolling the foam.
Scientists are developing earmuffs using high-tech materials to reduce
weight and bulk, but still effectively block noise. On the horizon may be
earplugs with built in two-way communication capability.
Still, the best hearing protector is the one that is comfortable and convenient
and that you will wear every time you are in an environment with hazardous
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Hearing Conservation Program Evaluation Checklist
Training and Education
Failures or deficiencies in hearing conservation programs
(hearing loss prevention programs) can often be traced to
inadequacies in the training and education of noise-exposed
employees and those who conduct elements of the program.
- Has training been conducted at least once a year?
- Was the training provided by a qualified instructor?
- Was the success of each training program evaluated?
- Is the content revised periodically?
- Are managers and supervisors directly involved?
- Are posters, regulations, handouts, and employee newsletters used
- Are personal counseling sessions conducted for employees having problems
with hearing protection devices or showing hearing threshold shifts?
Data indicate that employees who refuse to wear hearing
protectors or who fail to show up for hearing tests frequently work
for supervisors who are not totally committed to the hearing loss
- Have supervisors been provided with the knowledge required to supervise
the use and care of hearing protectors by subordinates?
- Do supervisors wear hearing protectors in appropriate areas?
- Have supervisors been counseled when employees resist wearing protectors
or fail to show up for hearing tests?
- Are disciplinary actions enforced when employees repeatedly refuse to
wear hearing protectors?
For noise measurements to be useful, they need to be related to
noise exposure risks or the prioritization of noise control efforts,
rather than merely filed away. In addition, the results need to be
communicated to the appropriate personnel, especially when follow-up
actions are required.
- Were the essential/critical noise studies performed?
- Was the purpose of each noise study clearly stated? Have noise-exposed
employees been notified of their exposures and appraised of auditory risks?
- Are the results routinely transmitted to supervisors and other key individuals?
- Are results entered into health/medical records of noise exposed employees?
- Are results entered into shop folders?
- If noise maps exist, are they used by the proper staff?
- Are noise measurement results considered when contemplating procurement
of new equipment? Modifying the facility? Relocating employees?
- Have there been changes in areas, equipment, or processes that have altered
noise exposure? Have follow-up noise measurements been conducted?
- Are appropriate steps taken to include (or exclude) employees in the hearing
loss prevention programs whose exposures have changed significantly?
Engineering and Administrative Controls
Controlling noise by engineering and administrative methods is
often the most effective means of reducing or eliminating the
hazard. In some cases engineering controls will remove requirements
for other components of the program, such as audiometric testing and
the use of hearing protectors.
- Have noise control needs been prioritized?
- Has the cost-effectiveness of various options been addressed?
- Are employees and supervisors appraised of plans for noise control
measures? Are they consulted on various approaches?
- Will in-house resources or outside consultants perform the work?
- Have employees and supervisors been counseled on the operation and
maintenance of noise control devices?
- Are noise control projects monitored to ensure timely completion?
- Has the full potential for administrative controls been evaluated?
Are noisy processes conducted during shifts with fewer employees? Do
employees have sound-treated lunch or break areas?
Monitoring Audiometry and Record Keeping
The skills of audiometric technicians, the status of the
audiometer, and the quality of audiometric test records are crucial
to hearing loss prevention program success. Useful information may
be ascertained from the audiometric records as well as from those
who actually administer the tests.
- Has the audiometric technician been adequately trained, certified, and
recertified as necessary?
- Do on-the-job observations of the technicians indicate that they perform
a thorough and valid audiometric test, instruct and consult the employee
effectively, and keep appropriate records?
- Are records complete?
- Are follow-up actions documented?
- Are hearing threshold levels reasonably consistent from test to test?
If not, are the reasons for inconsistencies investigated promptly?
- Are the annual test results compared to baseline to identify the presence
of an OSHA standard threshold shift?
- Is the annual incidence of standard threshold shift greater than a few
percent? If so, are problem areas pinpointed and remedial steps taken?
- Are audiometric trends (deteriorations) being identified, both in individuals
and in groups of employees? (NIOSH recommends no more than 5% of workers
showing 15 dB Significant Threshold Shift, same ear, same frequency.)
- Do records show that appropriate audiometer calibration procedures have
- Is there documentation showing that the background sound levels in the
audiometer room were low enough to permit valid testing?
- Are the results of audiometric tests being communicated to supervisors
and managers as well as to employees?
- Has corrective action been taken if the rate of no-shows for audiometric
test appointments is more than about 5%?
- Are employees incurring STS notified in writing within at least 21 days?
(NIOSH recommends immediate notification if retest shows 15 dB Significant
Threshold Shift, same ear, same frequency.)
Referrals to outside sources for consultation or treatment are
sometimes in order, but they can be an expensive element of the
hearing loss prevention program, and should not be undertaken
- Are referral procedures clearly specified?
- Have letters of agreement between the company and consulting physicians
or audiologists been executed?
- Have mechanisms been established to ensure that employees needing evaluation
or treatment actually receive the service (i.e., transportation, scheduling,
- Are records properly transmitted to the physician or audiologist, and
back to the company?
- If medical treatment is recommended, does the employee understand the
condition requiring treatment, the recommendation, and methods of obtaining
- Are employees being referred unnecessarily?
Hearing Protection Devices
When noise control measures are infeasible, or until such time as
they are installed, hearing protection devices are the only way to
prevent hazardous levels of noise from damaging the inner ear.
Making sure that these devices are worn effectively requires
continuous attention on the part of supervisors and program
implementors as well as noise-exposed employees.
- Have hearing protectors been made available to all employees whose daily
average noise exposures are 85 dBA or above? (NIOSH recommends requiring
HPD use if noises equal or exceed 85 dBA regardless of exposure time.)
- Are employees given the opportunity to select from a variety of appropriate
- Are employees fitted carefully with special attention to comfort?
- Are employees thoroughly trained, not only initially but at least once
- Are the protectors checked regularly for wear or defects, and replaced
immediately if necessary?
- If employees use disposable hearing protectors, are replacements readily
- Do employees understand the appropriate hygiene requirements?
- Have any employees developed ear infections or irritations associated
with the use of hearing protectors? Are there any employees who are unable
to wear these devices because of medical conditions? Have these conditions
been treated promptly and successfully?
- Have alternative types of hearing protectors been considered when problems
with current devices are experienced?
- Do employees who incur noise-induced hearing loss receive intensive counseling?
- Are those who fit and supervise the wearing of hearing protectors competent
to deal with the many problems that can occur?
- Do workers complain that protectors interfere with their ability to do
their jobs? Do they interfere with spoken instructions or warning signals?
Are these complaints followed promptly with counseling, noise control, or
- Are employees encouraged to take their hearing protectors home if they
engage in noisy non-occupational activities?
- Are new types of or potentially more effective protectors considered as
they become available?
- Is the effectiveness of the hearing protector program evaluated regularly?
- Have at-the-ear protection levels been evaluated to ensure that either
over or under protection has been adequately balanced according to the anticipated
ambient noise levels?
- Is each hearing protector user required to demonstrate that he or she
understands how to use and care for the protector? The results documented?
Keeping organized and current on administrative matters will help
the program run smoothly.
- Have there been any changes in federal or state regulations? Have hearing
loss prevention program’s policies been modified to reflect these changes?
- Are copies of company policies and guidelines regarding the hearing loss
prevention program available in the offices that support the various program
elements? Are those who implement the program elements aware of these policies?
Do they comply?
- Are necessary materials and supplies being ordered with a minimum of delay?
- Are procurement officers overriding the hearing loss prevention program
implementor's requests for specific hearing protectors or other hearing
loss prevention equipment? If so, have corrective steps been taken?
- Is the performance of key personnel evaluated periodically? If such performance
is found to be less than acceptable, are steps taken to correct the situation?
- Safety: Has the failure to hear warning shouts or alarms been tied to
any accidents or injuries? If so, have remedial steps been taken?
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