What is noise-induced hearing loss?

Every day, we experience sound in our surroundings, like the sounds from television and radio, household appliances, and traffic. Normally, these sounds are at safe levels that don’t damage our hearing. But sounds are often harmful once they are too loud, even for a quick time, or once they are both loud and long-lasting. These sounds can damage sensitive structures within the internal ear and cause noise-induced deafness (NIHL).

NIHL are often immediate or it can take an extended time to be noticeable. It are often temporary or permanent, and it can affect one ear or both ears. Even if you can’t tell that you simply are damaging your hearing, you'll have trouble hearing within the future, like not having the ability to know people when they talk, especially on the phone or during a noisy room. Regardless of how it'd affect you, one thing is certain: noise-induced deafness are some things you'll prevent.

What causes NIHL?

NIHL are often caused by a one-time exposure to an intense “impulse” sound, like an explosion, or by continuous exposure to loud sounds over an extended period of your time , such as noise generated in a woodworking shop.

Recreational activities which will put you in danger for NIHL include target shooting and hunting, snowmobile riding, taking note of MP3 players at high volume through earbuds or headphones, playing in a band, and attending loud concerts. Harmful noises at home may come from sources including lawnmowers, leaf blowers, and woodworking tools.

Sound is measured in units called decibels. Sounds at or below 70 A-weighted decibels (DBA), even after long exposure, are unlikely to cause deafness. However, long or repeated exposure to sounds at or above 85 DBA can cause deafness. The louder the sound, the shorter the amount of time it takes for NIHL to happen.

How can noise damage our hearing?

To understand how loud noises can damage our hearing, we've to know how we hear. Hearing depends on a series of events that change sound waves within the air into electrical signals. Our acoustic nerve then carries these signals to the brain through a posh series of steps.

1)    Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum.

2)   The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes.

3)   The bones in the middle ear couple the sound vibrations from the air to fluid vibrations in the cochlea of the inner ear, which is shaped like a snail and filled with fluid. An elastic partition runs from the start to the top of the cochlea, splitting it into an upper and lower part. This partition is named the membrane because it is the bottom , or ground floor, on which key hearing structures sit.

4)   Once the vibrations cause the fluid inside the cochlea to ripple, a traveling wave forms along the basilar membrane. Hair cells—sensory cells sitting on top of the basilar membrane—ride the wave.

5)   As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) that perch on top of the hair cells bump against an overlying structure and bend. Bending causes pore-like channels, which are at the ideas of the stereocilia, to open up. When that happens, chemicals rush into the cell, creating an electrical signal.

6)   The auditory nerve carries this electrical signal to the brain, which translates it into a sound that we recognize and understand.

What are the effects and signs of NIHL?

When you are exposed to bang over an extended period of your time , you'll slowly start to lose your hearing. Because the damage from noise exposure is typically gradual, you would possibly not notice it, otherwise you might ignore the signs of deafness until they become more pronounced. Over time, sounds may become distorted or muffled, and you would possibly find it difficult to know people once they talk or need to happen the quantity on the tv . The damage from NIHL, combined with aging, can cause deafness severe enough that you simply need hearing aids to magnify the sounds around you to assist you hear, communicate, and participate more fully in daily activities.

NIHL also can be caused by extremely loud bursts of sound, like gunshots or explosions, which may rupture the eardrum or damage the bones within the tympanic cavity. This kind of NIHL is often immediate and permanent.
Loud noise exposure also can cause tinnitus—a ringing, buzzing, or roaring within the ears or head. Tinnitus may subside over time, but can sometimes continue constantly or occasionally throughout a person’s life. Hearing loss and tinnitus can occur in one or both ears.

Sometimes exposure to impulse or continuous bang causes a short lived deafness that disappears 16 to 48 hours later. Recent research suggests, however, that although the loss of hearing seems to disappear, there could also be residual long-term damage to your hearing.

Can NIHL be prevented?

NIHL is that the only sort of deafness that's completely preventable. If you understand the hazards of noise and the way to practice good hearing health, you'll protect your hearing for all times. Here’s how:

Ø    Know which noises can cause damage (those at or above 85 DBA).

Ø    Wear earplugs or other protective devices when involved in a loud activity (activity-specific earplugs and earmuffs are available at hardware and sporting goods stores).

Ø    If you can’t reduce the noise or protect yourself from it, move away from it.

Ø    Be alert to hazardous noises in the environment.

Ø    Protect the ears of children who are too young to protect their own.

Ø    Make family, friends, and colleagues aware of the hazards of noise.

Ø    Have your hearing tested if you think you might have hearing loss.

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