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Are You at Risk?

About Hearing Loss

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Hearing Risk FAQ

About Tinnitus

Sound Check

Decibel Trivia

Say What?

Hearing Loss What Is It?

Hearing Advice -- Crabby





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When you notice a difference between loud sounds and quiet ones, your ears are perceiving changes in sound pressure level. Intensity (or volume) is measured in decibels (dB). Zero (0) dB is the softest sound that can be heard. Normal conversation is around 40dB to 60dB, a whisper around 30dB. A rock concert can average between 110 and 120 dB. Pain from hearing is subjective. Levels below 125 dB may be painful to some individuals. The sound from a jet plane is approximately 140 dB.

At rock shows, the dB level can be as great as 140 dB in front of the speakers, but less than 120 dB at the back which is still very loud and dangerous.Danger Zone

The maximum exposure time for unprotected ears per day is 8 hours at 85 dB SPL, A-weighted, slow response For every 3 dB increase in volume, the maximum exposure time is cut in half.

  • 95 dB - 4 hours

  • 100 dB - 2 hours

  • 110 dB - 30 min

  • 120 dB- 7.5 min

Many hearing professionals believe that these permissible levels are still too high for hearing safety. NIOSH, the National Institute for Occupational Safety and Health recommends 85 dB for eight hours a day.

Other sources of noise: boom cars, bars, dance clubs, motorcycles, auto races, monster trucks, farm and factory equipment, power tools, guns, sporting events, crowd noise, stereo headsets.

Hearing Damage

Noise-induced hearing loss affects both the quantity and the quality of sound. Understanding human speech becomes difficult because words become indistinct. Excessive sound exposure damages hearing by over-stimulating the tiny hair cells within the inner ear. There are between 15,000 and 20,000 of these microscopic sensory receptors in the cochlea (coke-lee-ah). When these hair cells are damaged, they no longer transmit sound to the brain. Sounds are muffled. Hearing damage through noise exposure is permanently lost. Hearing aids amplify the remainder of your hearing.

Is Your Hearing at Risk?

Warning signs:
After exposure to loud music or noise you may experience one or more of the following:

  • Ringing or buzzing in the ears

  • Slight muffling of sounds

  • Difficulty in understanding speech. You can hear all the words, but you can't understand them.

  • Difficulty in hearing conversation in groups of people when there is background noise, or in rooms with poor acoustics.

If you experience any of these early warnings, don't wait to seek help. Have your hearing checked by an audiologist, or have your ears examined by an ear specialist. Protect your hearing by wearing ear plugs or turning down the volume. Take breaks. Give your ears a chance to recover.

Who is an Audiologist

Who is an Otolaryngoloist

Types of Hearing Aids

How Our Hearing Works

ear diagramThe OUTER EAR acts like a funnel to direct sound waves from the air to the tympanic membrane (eardrum). Sound causes the tympanic membrane to vibrate. These vibrations cause the three bones in the MIDDLE EAR (malleus, incus, and stapes) to move mechanically. The middle ear sends these mechanical vibrations to the INNER EAR, where they are picked up by tiny hair cells (cilia) and sent as electrical impulses along the auditory nerve to the brain.

Hearing Loss: It's A Matter of Degrees

Degree of Hearing Loss can be mild, moderate, severe, or profound.

Mild (25-40 dB). A person with a mild hearing loss will have difficulty following conversation if the speaker is more than six feet away or if there's noise in the background.

Moderate (40-70 dB). A person with moderate hearing loss would be able to hear if the speaker is speaking loudly and at no more that 3 to 5 feet away. They'll also have trouble hearing with background noise and will need to wear a hearing aid to hear conversation.

Severe (70-90 dB). A person with a severe hearing loss would be able to hear someone's voice if the speaker shouts and is 1 foot away. Without a hearing aid the person would not be able to understand speech and only be able to hear some loud sounds( a siren, for example).

Profound (91 dB or more). A person with a profound hearing loss is only able to hear very loud sounds. With hearing aids they would probably be able to hear loud sounds, like perhaps a telephone ringing or a name being called but, it would be difficult to understand speech. With training their ability for understanding some speech may improve.

Types of Hearing Loss

28 Million Americans have a hearing loss; 80% of those affected have hearing damage that is irreversible and permanent.

17 million Americans are affected by sensorineural hearing damage resulting from heredity, birth, trauma, disease, advanced age, or exposure to noise.

A sensorineural hearing loss is damage to the hearing nerve in the inner ear.

Advances in hearing aid technology have made great improvements in total or at least partial rehabilitation. They can assist in understanding speech and improving the clarity of sound. They cannot restore hearing to normal in the way that eye glasses correct vision.

When there is difficulty in both the middle and inner ear, a mixed hearing loss (conductive and sensorineural) exists.

A conductive hearing loss occurs when the hearing nerve functions properly but there is difficulty in the outer or middle ear transmitting system. Sound can not conduct properly to the inner ear nerve or cochlea.

Conductive hearing loss can be the result of many different conditions. The most common is fluid in the middle ear. Fluid builds up behind the ear drum which sometimes becomes infected. This can be treated with antibiotics and other medications. If drug therapy fails, drainage can be accomplished through a small incision in the eardrum (myringotomy). Tubes may be inserted to provide middle ear aeration.

Otitis media is the most common form of temporary hearing loss among children.

Another cause of conductive hearing loss is the fixation of the hearing bones (otosclerosis) which can be corrected through a surgical procedure called a "stapedectomy." Holes or perforations in the eardrums and damaged hearing bones can be corrected by reconstructive surgery.

Hearing loss may be a symptom of ear disease. It is important to have your hearing examined by an ear specialist, (otologists or an otolaryngologist), or have your ears evaluated by an audiologist.

Rehabilitation advances in speech reading, counseling, auditory training, hearing aids and assistive listening devices (ALDs) help overcome the handicap of hearing loss. Hearing aids are now available that fit entirely within the ear canal and are practically invisible to the human eye.

Hearing loss in the profoundly deaf can sometimes be aided by a cochelear implant. This is a device which consists of a magnetic coil placed in the mastoid bone behind the ear. An electrode connects to the inside of the inner ear and stimulates the hearing nerve which enables sound to be perceived.

2 Million Americans are Profoundly Deaf

There is a difference between being deaf and being hard-of-hearing. People are either born deaf or become deaf later in life through accident or illness. American Sign Language (ASL) is used by most culturally deaf people as their primary means of communication. ASL is recognized as a language of its own and is the fourth most commonly used language in the United States. Hard-of hearing people usually use their residual hearing and communicate verbally.





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