Answers to Questions Your Employees May Ask (NIOSH)

Don't we lose our hearing as we age?
It's true that most people's hearing test gets worse as they get older. But for the average person, aging does not cause impaired hearing before at least the age of 60. People who are not exposed to noise and are otherwise healthy, keep their hearing for many years.
People who are exposed to noise and do not protect their hearing begin to lose their hearing at an early age. For example, by age 25 the average carpenter has "50-year old" ears! That is, by age 25, the average carpenter has the same hearing as someone who is 50 years old and has worked in a quiet job.

Can you poke out your eardrums with earplugs?
That is unlikely for two reasons. First, the average ear canal is about 1¼ inches long. The typical ear plug is between ½ to ¾ inch long. So even if you inserted the entire earplug, it would still not touch the eardrum. Second, the path from the opening of the ear canal to the eardrum is not straight. In fact, it is quite irregular. This prevents you from poking objects into the eardrum.

We work in a dusty, dirty place. Should I worry that our ears will get infected by using earplugs?
Using earplugs will not cause an infection. But use common sense. Have clean hands when using earplugs that need to be rolled or formed with your fingers in order for you to insert them. If this is inconvenient, there are plenty of earplugs that are pre-molded or that have stems so that you can insert them without having to touch the part that goes into the ear canal.

Can you hear warning sounds, such as backup beeps, when wearing hearing protectors?
The fact is that there are fatal injuries because people do not hear warning sounds. However, this is usually because the background noise was too high or because the person had severe hearing loss, not because someone was wearing hearing protectors. Using hearing protectors will bring both the noise and the warning sound down equally.

So if the warning sound is audible without the hearing protector, it will usually be audible when wearing the hearing protector. For the unusual situations where this is not the case, the solution may be as simple as using a different hearing protector. Also, many warning systems can be adjusted or changed so warning signals are easier to detect.

Won't hearing protectors interfere with our ability to hear important sounds our machinery and equipment make?
Hearing protectors will lower the noise level of your equipment; it won't eliminate it. However, some hearing protectors will reduce certain frequencies more than others; so wearing them can make noises sound different. In cases where it's important that the sound just be quieter without any other changes, there are hearing protectors that can provide flat attenuation.
There are also noise-activated hearing protectors that allow normal sounds to pass through the ear and only "turn-on" when the noise reaches hazardous levels. There are even protectors that professional concert musicians use that can lower the sound level while retaining sound fidelity.

Will we be able to hear each other talk when wearing hearing protectors?
Some people find they can wear hearing protectors and still understand speech. Others will have trouble hearing speech while wearing hearing protectors. Being able to hear what other people say depends on many things: distance from the speaker, ability to see the speaker's face, general familiarity with the topic, level of background noise, and whether or not one has an existing hearing impairment. In some cases, wearing hearing protectors can make it easier to understand speech.
In other instances, people may be using hearing protectors to keep out too much sound. You may need a protector that reduces the sound enough to be safe without reducing the sound too much to hear speech at a comfortably loud level. For those people who work in noise and must communicate, it may also be necessary to use communication headsets. Allow your employees to try different protectors. Some will work better than others at helping them to hear speech, and different protectors may work better for different people.

How long does it take to get used to hearing protectors?
Think about getting a new pair of shoes. Some shoes take no time to get used to. Others, even though they are the right size, can take a while to get used to. Hearing protectors are no different from other safety equipment in terms of getting used to them. But if hearing protectors are the wrong size, or are worn out, they will not be comfortable.
Also, workers may need more than one kind of protector at their job. For example, no one would wear golf shoes to go bowling. If hearing protectors are not suitable for the work being done, they probably won't feel comfortable.

How long can someone be in a loud noise before it's hazardous?
The degree of hearing hazard is related to both the level of the noise as well as to the duration of the exposure. But this question is like asking how long can people look at the sun without damaging their eyes. The safest thing to do is to ensure workers always protect their ears by wearing hearing protectors anytime they are around loud noise.

How can I tell if a noise situation is too loud?
There are two rules: First, if you have to raise your voice to talk to someone who is an arm's length away, then the noise is likely to be hazardous. Second, if your ears are ringing or sounds seem dull or flat after leaving a noisy place, then you probably were exposed to hazardous noise.

How often should your hearing be tested?
Anyone regularly exposed to hazardous noise should have an annual hearing test. Also, anyone who notices a change in his/her hearing (or who develops tinnitus) should have his or her ears checked. People who have healthy ears and who are not exposed to hazardous noise should get a hearing test every three years.

Since I already have hearing loss and wear a hearing aid, hearing prevention programs don't apply to me, right?
If you have hearing loss, it's important to protect the hearing that you have left. Loud noises can continue to damage your hearing making it even more difficult to communicate at work and with your family and friends.

Employee Hearing Conservation Training Program

When feasible engineering and administrative controls don't adequately reduce noise exposures, you (the employer) must provide and pay for hearing protection devices (HPDs).


OSHA's Occupational Noise Exposure standard is in the General Industry regulations at §1910.95. When employees are exposed to 85 or more decibels (dB) averaged over an eight-hour period, the employer must implement a hearing conservation program that includes noise monitoring, hearing tests, hearing protection devices (HPDs), recordkeeping, and an annual training program. All of these provisions can be overwhelming to an employee, but a thorough training program can help employees understand how the program works.

Specific Training Elements

  1. Introduce the hazards of noise.
    The most obvious hazard from being exposed to excessive noise is that it can cause noise-induced hearing loss.
    In addition to causing temporary or permanent hearing loss, excessive noise can:
    • Cause you to miss hearing important warnings or instructions;
    • Cause fatigue from the strain of talking and listening over the noise; and
    • Cause increased blood pressure, headaches, sleeping disorders, and other ailments.
    Trainer's noteTell employees not to believe that they will "get used to" the noise in the workplace.
  2. Describe how engineering controls can reduce or eliminate noise hazards.
    The most effective way to control noise is to eliminate it by using engineering controls. Generally, the term "engineering controls" means using materials and equipment.
    Common examples of engineering controls are:
    • Installing a muffler on a machine,
    • Erecting acoustical enclosures and barriers around noisy equipment,
    • Installing sound absorbing material on walls,
    • Installing vibration mounts under equipment,
    • Making sure moving parts on machinery are properly lubricated, and
    • Buying quieter equipment.
    Trainer's noteProvide examples of how engineering controls have been used to reduce the noise in your workplace.
  3. Explain how administrative controls can reduce noise.
    The next way to control noise hazards is through administrative controls. This involves managing how work is assigned.
    Examples include operating a noisy machine only during a shift when fewer people are exposed, or moving an employee to a less noisy job once he has been exposed to a certain daily dose of noise.
    Even providing quiet areas where employees can get relief from workplace noise is an example of an administrative control. Lunchrooms and break areas should be located away from noise.
    Trainer's noteGive examples of any administrative controls in place at your facility.
  4. Outline the requirements of a hearing conservation program.
    When it is not feasible to otherwise reduce noise to a safe level, the employer has to implement a hearing conservation program. A hearing conservation program is required for all employees whose noise exposure levels equal or exceed an 8-hour time-weighted average of 85 dB.
    The hearing conservation program includes provisions for:
    • Monitoring noise levels,
    • Providing employees with audiometric testing,
    • Using appropriate HPDs,
    • Training, and
    • Recordkeeping.
  5. Describe how noise levels are monitored.
    Noise monitoring is done for many reasons, including:
    • To determine whether noise levels could contribute to hearing loss,
    • To determine whether noise interferes with communication or warning signals,
    • To identify employees for the hearing conservation program,
    • To set priorities for noise control efforts,
    • To identify areas where hearing protection practices are needed,
    • To evaluate specific sources of noise, and
    • To evaluate the success of noise control efforts.
    Monitoring is conducted using sound level meters, dosimeters worn by employees, or other more sophisticated acoustical equipment. Employees must be able to observe the monitoring. Employees who are exposed at or above an 8-hour time-weighted average of 85 dB must be given the results of the monitoring.
    Trainer's noteDisplay your noise monitoring equipment.
  6. Explain how you provide hearing tests.
    Employers have to provide affected employees with hearing tests in order to know if the hearing conservation program is effective.
    A technician uses an instrument (an audiometer) to send sounds (tones) through headphones. The person being tested responds to the test sounds. The chart that records responses to the test sounds is called an audiogram. Employees can request test results.
    You first have a baseline audiogram. This is followed up with annual audiograms. If tests show that you have experienced a certain change in the hearing threshold relative to the baseline audiogram, additional testing or examinations may be necessary, and you need to be refitted and retrained in the use of HPDs.
    Trainer's noteYou may want to have a separate session to explain the audiometric testing program so that employees know what to expect during the tests.
  7. Demonstrate how to use HPDs.
    By wearing HPDs, you reduce the level of sound entering the ear. Three typical types of HPDs are:
    • Earmuffs,
    • Ear canal caps, and
    • Earplugs.
HPDs must be available (at no cost) to any employee who is exposed at or above an 8-hour time-weighted average of 85 dB. Under certain conditions, employees can be requiredto wear the HPDs. You must be able to select HPDs from a variety of suitable choices. The HPDs must fit properly, and you must be trained to use and wear them correctly.
For example, to correctly insert foam earplugs, follow the manufacturer's instructions. In general:
  1. Roll the earplug between your fingers so it is tightly compressed into a smooth, long, slender cylinder.
  2. Reach over your head with the opposite hand and gently lift and pull your ear to straighten the ear canal.
  3. While holding your ear, insert the compressed earplug with your other hand, and hold it in place with a finger while it expands into your ear.
Trainer's noteHave volunteers help you demonstrate how to wear and adjust HPDs.
Quiz: Have you heard about hearing conservation?
For each question, show if you think the statement is "True" or "False."
  1. Noise can cause temporary hearing problems. True/False
  2. Putting a noisy machine on a rubber mat can help reduce noise. True/False
  3. Employees have to buy the earplugs they use. True/False
  4. You don't need a hearing test to know if you're losing your hearing. True/False
  5. Employees have to stay away while noise monitoring is done. True/False
Name: __________________ Date: ________________
Answers to Quiz
  1. True
  2. True
  3. False
  4. False
  5. False

Develop a Hearing Conservation Program

An effective hearing conservation program can prevent hearing loss, improve employee morale and a general feeling of well-being, increase quality of production, and reduce the incidence of stress-related disease. Employers must administer a continuing, effective hearing conservation program whenever employee noise exposures are at or above an eight hour time-weighted average (TWA) of 85 dBA or, equivalently, a dose of 50 percent. This is referred to as the action level.

Minimum requirements of a hearing conservation program include:
  • Monitoring program,
  • Audiometric testing program,
  • Hearing protection devices,
  • Employee training, and
  • Recordkeeping.

Monitoring Program

Employers have to develop and implement a monitoring program whenever information indicates that any employee's exposure may equal or exceed the action level. The sampling strategy must be designed to identify all employees for inclusion in the hearing conservation program and enable the proper selection of hearing protectors.
The monitoring requirement is performance-based, as it allows employers to choose a monitoring method that best suits each individual work situation. Either personal or area monitoring may be used. If there are circumstances that may make area monitoring generally inappropriate, such as high worker mobility, significant variations in sound level or a significant component of impulse noise, then the employer must use representative personal sampling unless it can be shown that area sampling produces equivalent results.
Noise measurements must integrate all continuous, intermittent, and impulsive noise levels from 80 to 130 dBA. Monitoring must be repeated whenever a change in production, process, equipment or controls increases noise exposures to the extent that additional employees may be exposed at or above the action level, or the attenuation provided by hearing protectors used by employees is inadequate.
The employer must notify each employee who is exposed at or above the action level of the results of the monitoring and provide them with an opportunity to observe noise monitoring procedures.

Hearing Protection Devices (HPDs)

Hearing protection devices (HPDs) are considered the last option to control exposures to noise. HPDs are generally used during the necessary time it takes to implement engineering or administrative controls, or when such controls are not feasible.
Employers must make HPDs available at no cost to all employees exposed at or above the action level and provide replacements as necessary. Further, they must ensure that HPDs are worn by employees where feasible administrative and engineering controls fail to reduce sound levels within those listed in Table G-16, or who are exposed at or above the action level and who have not yet had a baseline audiogram established or have experienced a standard threshold shift (STS).

HPD Selection and Use
Employees must be given the opportunity to select their HPDs from a suitable variety. Generally, this should include a minimum of two devices, representative of at least two different types. The employer must provide training in the use and care of all protectors provided to employees and ensure proper initial fitting and supervise their correct use.

HPD Attenuation
Attenuation refers to the damping or decrease of noise levels as a result of wearing HPDs. The employer has to evaluate HPD attenuation for the specific noise environments in which the HPD will be used. HPDs must attenuate employee exposure to at least an eight hour time-weighted average of 90 dBA.
For employees who have experienced a standard threshold shift (STS), HPDs must attenuate exposure at or below the action level of 85 dBA-TWA (time-weighted average). The adequacy of the HPDs must be reevaluated whenever employee noise exposures increase to the extent that they may no longer provide adequate attenuation. The employer must provide more effective hearing protectors as necessary.

Employee Training

OSHA requires employers to establish a training program for all employees with noise exposures at or above the action level and ensure employee participation. Training must be repeated annually for each employee in the hearing conservation program and the information must be updated to be consistent with changes in protective equipment and work processes.
The employer must ensure that each employee is informed of the following:
  • The effects of noise on hearing.
  • The purpose of hearing protectors, the advantages, disadvantages, and attenuation of various types, and instructions on selection, fitting, use, and care.
  • The purpose of audiometric testing and an explanation of test procedures.

Access to Information and Training Materials
Employers have to make copies of the noise standard available to affected employees and post a copy in the workplace. They also are required to provide affected employees with any informational materials pertaining to the standard that are supplied to the employer by OSHA and give OSHA copies of all material relating to the employer's training and education program (on request).


OSHA has specific recordkeeping requirements for noise monitoring and employee testing results.

Exposure Measurements
Employers must maintain an accurate record of all employee exposure measurements. These records must be retained for two years.

Audiometric Test Records
The employer must retain all employee audiometric test records. These records must include:
  • Name and job classification of the employee.
  • Date of the audiogram.
  • The examiner's name.
  • Date of the last acoustic or exhaustive calibration of the audiometer.
  • Employee's most recent noise exposure assessment.
Additionally, the employer has to maintain accurate records of the background sound pressure level measurements in audiometric test rooms. These records must be maintained for the duration of the affected worker's employment.

Access to Records
All records required by the noise standard must be provided upon request to employees, former employees, representatives designated by the individual employee, and OSHA.
Employers who cease to do business must transfer to the successor employer all records required by the noise standard. The successor employer has to retain these records for the remainder of the periods described previously.

Recording Hearing Loss on the 300 Log

Noise-induced hearing loss is a serious and irreversible condition. However, it is not the type of occupational injury that typically requires days away from work for recuperation. All work-related hearing losses of 10 decibel shifts that result in a total 25 decibel shift above audiometric zero have to be recorded on the 300 Log.

Audiometric Zero and STS
A standard threshold shift (STS) is a change in hearing threshold, relative to an employee's baseline audiogram (hearing test), averaging 10 decibels (dB) or more at 2,000, 3,000, and 4,000 hertz (Hz) in one or both ears. If an employee's audiogram reveals that a work-related STS has occurred in one or both ears, and the total hearing level is 25 decibels or more above audiometric zero in the same ear(s) as the STS, the case is recordable.
If you have an employee with a recordable STS, document the case by checking the "hearing loss" column (M)(5) on the OSHA 300 Log.

Retesting allows you to exclude false positive results and temporary threshold shifts from the data. If you retest the employee's hearing within 30 days of the first test, and the retest does not confirm the STS, you are not required to record the hearing loss case on the OSHA 300 Log. However, if the retest confirms the STS, record the hearing loss illness within seven calendar days of the retest.

Hearing Loss that Occurs with Aging
You may take into account the hearing loss that occurs as a result of the aging process and retest an employee who has an STS on an audiogram to ensure that the STS is permanent before recording it. When comparing audiogram results, adjust the results for the employee's age when the audiogram was taken using Tables F-1 or F-2, as appropriate, in Appendix F of the Occupational Noise Exposure standard.

Noise Dose
Hearing loss is presumed to be work-related if the employee is exposed to noise in the workplace at an 8-hour time-weighted average of 85 dBA or greater, or to a total noise dose of 50 percent, as defined in OSHA's noise exposure standard.
Noise dose is defined as the amount of actual exposure to noise relative to its permissible exposure limit. A dose greater than 100 percent represents exposure above the limit. For hearing loss cases where the employee is not exposed to this level of noise, refer to the rules in §1904.5 to determine if the hearing loss is work-related.
If a physician determines that the hearing loss is not work-related or has not been significantly aggravated by occupational noise exposure, you are not required to consider the case work-related or to record it on the 300 Log. For example if the hearing loss occurred before the employee was hired; or hearing loss that is unrelated to workplace noise, such as off the job traumatic injury to the ear or infections.
Use this 'decision tree' to determine whether the results of a audiometric exam given on or after January 1, 2003 reveal a recordable STS.

Note: In all cases, use the most current baseline to determine recordability as you would to calculate a STS under the hearing conservation provisions of the noise standard (§1910.95). If an STS occurs in only one ear, you may only revise the baseline audiogram for that ear.
* The audiogram may be adjusted for presbycusis (aging) as set out in 1910.95.
** A separate hearing loss column on the OSHA 300 Log beginning in Calendar year 2004.

Controlling Workplace Noise

Engineering Controls

Workplace safety and health specialists agree that engineering controls are the best way to control noise. That's true if the engineering control is effective, practical, and affordable. When you replace a noisy machine with a quiet one, modify it to make it quieter, or change the sound path so that the noise never reaches the listener, you're using an engineering control.
If you have an old, noisy electric hand drill, you can replace it with a newer, quieter one. But, if you have a large noisy chipper/shredder, replacing it may not be practical. Instead, you might enclose the shredder to isolate the noise.
Enclose the Offending Equipment
Creative solutions may also be effective ones. Construction workers were using a concrete mixer to de-grease metal parts by tumbling them in sawdust — effective but noisy. To reduce the noise level to below 85 decibels, the employer built an enclosure around the mixer with two-by-fours and acoustic sound board, sealing the access door with polyurethane foam. The cost was minimal and the design was effective; it lowered noise levels to 78 decibels.
Increase the Distance
When you double the distance between the worker and the sound source, you decrease the sound pressure level by six decibels. For example, a hazardous 96-decibel noise source at five feet is a safe 84 decibels at 20 feet.
Reduce the Impact
When you reduce the height that materials collected in bins and boxes will drop, you can quiet noisy processes. Consider lining containers with damping materials such as plastic or rubber to keep them quiet.
Applying practical engineering controls to a noise problem can be challenging because there may not be ready-to-order solutions. You're more likely to find a solution when you:
  • Understand what's causing the noise.
  • Determine how the noise is reaching the worker.
  • Identify the most appropriate point, or points, at which to control the noise, either at the source, along the sound path, or at the worker.

Administrative and Work Practice Controls

Unlike engineering controls that prevent hazardous noise from reaching a worker, administrative controls manage workers' activities to reduce their exposure. Closely related to administrative controls are work practice controls, which emphasize safe practices.
Administrative and work-practice controls are usually less expensive than engineering controls because there are no significant capital costs involved in changing or modifying equipment. In some cases, administrative controls can reduce employee exposure to noise and increase productivity by rotating employees through a demanding, noisy task. Work practice controls can also improve performance by emphasizing safe work practices.
Administrative and work practice controls usually may not be as effective as engineering controls because they don't control the noise exposure. Noisy machines are still noisy and the exposure is still present. Some controls that can be used to reduce exposure include:
  • Reduce the time employees spend working in noisy areas;
  • Rotate two or more employees so that each is exposed to noise less than 85 decibels, averaged over an eight-hour day.
  • Shut down noisy equipment when it's not needed for production.
  • Ensure that employees maintain equipment so that it runs smoothly and quietly.
  • Ensure that employees know how to perform their tasks and operate equipment at safe noise levels.
  • Use warning signs to identify work areas where noise exceeds safe levels.
  • Encourage employees to report noise hazards to supervisors.
If you can't eliminate or control noise with an engineering control, you may be able to control it with an administrative control. However, if an administrative control won't reduce employee exposures to safe levels, you'll need to consider a third noise-control tool — hearing protectors.

Personal Protective Equipment: Hearing Protectors

When workplace noise equals or exceeds 85 dBA, averaged over an eight-hour period, can't be reduced through engineering, administrative, or work practice controls, employees must be provided with hearing protection. Those who receive hearing protectors must have the opportunity to select them from a variety of types that are compatible with their work tasks. Employees must also be properly fitted and trained to use and care for their hearing protectors.
There are two types of hearing protectors: ear plugs and earmuffs. Both types reduce the pressure of sound that reaches the eardrum and are the next line of defense when noise levels can't be reduced to safe levels with engineering or administrative controls.
Expandable Foam Plugs
Expandable foam 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-fitsmost" 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
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.
Miscellaneous Devices
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.
Select the Right Protection
The best hearing protector is the one that is comfortable and convenient and that will be worn every time a person is in an environment with hazardous noise. Select hearing protectors based on comfort, convenience, and compatibility. Employees won't wear hearing protectors that are uncomfortable or difficult to use or that interfere with their work. To ensure they will wear the protectors, allow employees to choose, with the help of a person trained in fitting hearing protectors, from among a variety of appropriate types and sizes.
Most hearing protectors are labeled with a noise reduction rating (NRR) indicating a protection level in decibels. However, these ratings are not reliable outside of a testing laboratory, which is where they received the rating. The NRR rating tends to overestimate the protection a hearing protector will provide under realworld conditions.
One way to estimate the real-world effectiveness of a hearing protector is to subtract 7 dB from the manufacturer's NRR as shown below:
  • Noise level to which the worker is exposed, averaged over an eight-hour period...95dBA
  • NRR shown on the hearing protector label .......25 decibels
  • Subtract 7 dB from the NRR .............25 - 7 = 18
  • Subtract 18 dB from 95 dBA ........95dBA - 18dB = 77dBA
This hearing protector may be able to reduce the worker's exposure from 95 dBA to 77 dBA.

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