Hearing loss caused by noise can occur
in people of any age. It may develop suddenly or gradually, depending on the
source and intensity of the noise. Noise can affect hearing in several
When a sudden, extremely loud sound, such as an explosion, a gunshot, or a
firecracker close to the ear, damages any of the structures in the ear and
produces an immediate, severe, and permanent hearing loss. This type of injury
often requires immediate medical attention.
When loud sounds (such as
from a rock concert) cause a temporary ringing and hearing loss. Sounds may
also seem muffled. These effects usually don't last more than a few hours,
although they may sometimes last several days or weeks. Repeated exposure to
sounds that cause temporary threshold shifts can gradually lead to permanent
threshold shifts, commonly referred to as noise-induced hearing loss.
Repeated, frequent exposure to loud or moderately loud sounds over a long
period of time (often years). Though permanent, this kind of hearing loss is
almost entirely preventable.
How loud a noise is and how long you are around it determine
whether a noise is harmful. On-the-job (occupational) noise is one of the most
common sources of harmful noise, largely because you are around it all day for
years. For instance, if you work in construction, in a factory, or are in the
military, you may be around harmful noise for several hours each day.
The sounds of recreation and daily activities over many years can also
damage the ear and cause hearing loss. These include:
The noise of power
tools, such as chainsaws or electric drills.
The noise from lawn
mowers, household appliances (such as blenders and vacuum cleaners), and
vehicles (such as snowmobiles and motorcycles).
You can reduce harmful noise levels and prevent noise-induced
damage to your hearing by avoiding noisy situations whenever you can. When you
can't avoid noisy situations, wear hearing protectors such as earplugs or
Noise-induced hearing loss is usually permanent and
cannot be reversed. Hearing aids, which make sounds louder, are often helpful
for this type of hearing loss.
How does noise-induced hearing loss develop?
heard, sound energy has to be strong enough to bend tiny hair cells in the
cochlea, a part of the
inner ear. The force of loud noise can damage these hair cells. A small amount
of damage may have no effect on hearing. But with repeated exposure to noise,
more of the hair cells are damaged, resulting in hearing loss.
Noise-induced hearing loss usually affects both ears. But one ear
may be affected more than the other if you have had repeated, long-term
exposure to a loud sound that is always coming from the same direction, such as
gunfire that is always near the same ear.
How this information was developed to help you make better health decisions.