Exposure to loud noise is the most common cause of hearing loss. Noise-induced hearing loss (NIHL) can be prevented but not reversed.
Sounds entering your ear pass through your eardrum and into the inner ear. Tiny hairs in the inner ear change the sound waves into nerve impulses. Hearing nerves carry these impulses to the brain. The brain interprets the nerve impulses as sound. Different sounds affect different parts of the ear. This allows the brain to know one sound from another, such as vowels from consonants.
You are born with about 30,000 hair cells in the inner ear. That's all you get. If some of these cells are destroyed, the cells are not replaced. The hairs in the inner ear are very sensitive and fragile. They can be destroyed by loud noise.
The hair cells in the inner ear can be destroyed by noise in 2 ways.
The loudness of sound is measured in decibels. For example, normal conversation is approximately 60 decibels. The humming of a refrigerator is 40 decibels, and city traffic noise can be 80 decibels. Sounds that are less than 80 decibels, even after long exposure, are unlikely to cause hearing loss. Noise levels greater than 80 decibels can be damaging. Motorcycles, firecrackers, and firearms can produce sounds from 120 to 140 decibels and can cause hearing loss.
Here are some sounds that can cause hearing loss after continued exposure:
For most people, a noise louder than 120 decibels hurts. If, after exposure to noise, you have a buzzing, ringing, crackling, or roaring sound in your ears, or other people's speech sounds muffled, then the noise may have damaged your hearing. Feelings of ear fullness or pressure may also happen after you hear a loud noise. These symptoms may start to go away after a few minutes or they may last a couple of days or longer. The sounds in your ear, called tinnitus, may continue constantly or occasionally throughout your life.
As noise exposure is repeated, more cells are damaged and the hearing loss can become permanent and more severe. The loss may go unnoticed for a while because it happens gradually. The first noticeable symptom is the loss of the ability to hear higher pitched sounds, such as birds singing. Sounds may become distorted or muffled and it may be hard for you to understand speech.
Besides hurting your hearing, noise can affect your body in other ways.
Hearing loss is detected with a hearing test.
Once the ear's tiny hairs are destroyed, they cannot be repaired. If you have a hearing loss from too much loud noise, the best thing you can do is to protect your ears from further damage by avoiding noise whenever possible. When you cannot avoid noise, use hearing protection. If you have hearing loss, hearing aids can often help you hear better.
Hearing loss from noise can be prevented with proper precautions:
See your provider if: