Exposure to unsafe noise levels is the leading cause of hearing loss among workers. Understand how noise affects your hearing and what you can do to keep work-related hearing loss at bay.
Noise in the workplace not only can annoy you, but also can harm you. Noise-induced hearing loss from continuous or intermittent exposure to noise is the most common work-related medical problem.
Hearing loss from noise exposure occurs so gradually you might not realize you're losing your hearing. Unfortunately, once you've lost some hearing, the loss is permanent and irreversible. But hearing loss from noise exposure is completely preventable. Keep your hearing intact by understanding when occupational noise puts your hearing at risk and what you can do to protect your hearing.
When is workplace noise too loud?
To help protect your hearing on the job, know three things about noise exposure: decibel levels, duration and noise pattern.
Decibels (db) are units used to indicate sound intensity or volume. Soft sounds are barely audible. Loud ones can cause pain in your ear. Between these levels is the range of sounds you're exposed to every day.
A typical conversation is about 60 db. A lawnmower sounds in at about 90 db. Exposure for more than eight hours a day to noise levels at 85 db or higher puts your hearing at risk. The Occupational Safety and Health Administration (OSHA) requires that employees exposed to such levels have their hearing monitored regularly.
What kind of decibel levels are you exposed to during a typical workday? To give you an idea, compare noises around you to these specific sounds and their corresponding decibel levels:
|Sound levels of common noises |
|Decibels ||Noise source |
| ||Safe range |
|60 ||Normal conversation, bird song |
|80 ||Heavy traffic, ringing telephone |
| ||Risk range |
|85 to 90 ||Motorcycle, snowmobile |
|90 ||Hair dryer, power lawn mower |
|95 to 105 ||Hand drill, spray painter, bulldozer |
|110 ||Chain saw |
| ||Injury range |
|120 ||Ambulance siren |
|140 ||Jet engine at takeoff |
|165 ||Shotgun blast |
Besides sound intensity, the length of time you're exposed to a noise plays a role in hearing loss. The longer you're exposed, the greater your risk of hearing loss. For every 5-decibel increase over 90 db in sound intensity, cut your time exposure in half.
Below are the maximum noise levels on the job to which you should be exposed without hearing protection — and for how long.
|Maximum job-noise exposure allowed by law |
|Sound level, decibels ||Duration, daily |
|90 ||8 hours |
|92 ||6 hours |
|95 ||4 hours |
|97 ||3 hours |
|100 ||2 hours |
|102 ||1.5 hours |
|105 ||1 hour |
|110 ||30 minutes |
|115 ||15 minutes |
Pay attention to the pattern of your noise exposure. Is it continuous, impulsive, intermittent or fluctuating?
- Continuous. Continuous noise is ongoing, such as the hum of the air-conditioning system in your office.
- Impulsive. Impulsive noise happens suddenly and ends quickly, and you may find it startling. Examples include a gunshot or a firecracker.
- Intermittent. Intermittent noise comes and goes, such as the sound you hear when the telephone rings.
- Fluctuating. Fluctuating noise can be both intermittent and ongoing, such as the ebb and flow of sounds that come from street traffic.
A noise that ranks lower on the decibel scale but that continues for longer periods of time actually may be more harmful to your hearing than is a higher intensity noise that's intermittent.
On the job: Could you be at risk?
If you're like millions of U.S. workers, you're exposed to noise levels on the job that put your hearing at risk. You might also be at risk of hearing loss if you're exposed to certain solvents, heavy metals or tobacco smoke. These substances (ototoxic agents) may compound the effects of a noisy environment on your hearing.
Some jobs are a bigger threat for hearing loss than others. Firefighters, police officers or emergency personnel, for example, are routinely exposed to sirens as well as loud noises on the scene of a disaster or emergency. Factory workers, construction workers, farmers or heavy-industry workers often use equipment that generates unsafe levels of noise.
If you suspect unsafe levels of noise in your workplace, talk to your employer about measuring sound levels in your work area. You may be asked to wear a device (dosimeter) to measure the average noise levels of the sounds you're exposed to during your time on the job.
How you can protect your hearing
|Earplugs come in a variety of shapes and sizes. |
Work-related hearing loss is preventable but not reversible. Once your ears are damaged by noise, hearing loss is permanent.
Take steps to prevent work-related hearing loss:
- Wear hearing protectors. A variety of specially designed hearing protectors guard your ears by reducing most loud sounds to an acceptable level — below 85 db. Hearing protectors decrease the intensity of sounds that reach your eardrum. You can use earplugs or earmuffs. Either can be purchased over-the-counter or can be custom-made.
|Earmuffs with cushioned ear pieces protect your hearing in a noisy environment. |
The best hearing protection device is the one you'll wear correctly the entire time you're exposed to excessive noise. Whether you choose earplugs or earmuffs, look for something that offers an airtight seal. Try both kinds to see which fits or feels best. The earplugs or earmuffs must fit snugly to block out the damaging sounds. If your workplace has sound levels that exceed 105 db, consider wearing both earplugs and earmuffs at the same time. Worn together, they offer greater protection. If you're unsure about the proper fit or which device is best for you, consult a hearing specialist (audiologist).
- Limit your exposure. This includes the amount of time spent exposed to the noise and your proximity to it. You can limit your exposure by taking breaks or moving away from the noise source. If that's not possible, always wear protective equipment when workplace noise is louder than 85 db. Protective devices only protect if worn consistently. Removing those devices for only an hour during an eight-hour workday makes the equipment about one-third as effective for preventing hearing loss.
- Be aware of noises around you. You might unknowingly contribute to your risk of hearing loss. Whenever you can, turn down the volume on radios or speakers. Avoid shouting to be heard by someone. A rule of thumb: If you can't hear or be heard by someone within three feet of you because of noise, the noise is loud enough to damage your ears.
- Give your ears a rest. Alternate a noisy activity with a quieter activity. Find a quiet area to take your breaks.
- Use caution when listening to headphones. If you routinely listen to a personal stereo system at work, or if your job requires the use of headphones, such as for transcription purposes, be careful. Set the volume at a comfortable level for a quiet setting. If you find yourself turning up the volume to drown out background noise, then it's probably too loud and you're at risk of damaging your ears. Keep the volume at a safe level. If you're listening to music and turn up the volume for a favorite song, turn it back down once the song's over.
- Test your hearing. If you work in a noisy environment, have your hearing tested regularly by a qualified audiologist. Such testing can provide early detection of hearing loss. If you've lost some hearing, you can learn what to do to prevent further hearing loss. OSHA requires employers to offer hearing conservation programs, including regular testing and preventive measures, to employees exposed to average noise levels of 85 db or greater.
- Seek the help of your employer. If you don't currently have any hearing protectors, ask your employer to provide them. Most workplaces offer hearing protection equipment at no cost to employees. An employer may also explore ways to reduce noise levels confined to a certain area, such as applying acoustic tiles to ceilings or walls near a loud piece of equipment.
Focus on keeping your ears healthy when you're away from work, too. Exposure to noise has a cumulative effect — noise-related damage to your hearing doesn't end once you've left for the day. If your home is noisy or your recreational activities are loud, they count toward your total noise exposure. It all adds up during the course of your lifetime.
Last Updated: 03/04/2005