Learn more about noise-induced hearing impairment and what you can do to prevent it.
Approximately 36 million Americans have hearing loss and one in three developed their hearing loss due to noise exposure. Noise-induced hearing impairment is caused by damage to the delicate hair cells found in the inner ear. These are small sensory cells that convert the sounds we hear (sound energy) into electrical signals that travel to the brain. Once damaged, hair cells cannot grow back, causing permanent hearing impairment. Hearing protection decreases the intensity, or loudness, of noise and helps preserve hearing.
Harmful sounds include those that are too loud and last too long or are very loud and sudden. Harmful noise exposure can include a one-time intense sound such as an explosion, or continuous exposure to loud sounds over an extended period such as sitting too close to the speakers during a concert.
The sound level is dangerous if:
- You must shout to be heard.
- The noise is painful to your ears.
- The noise makes your ears ring.
- You have decreased or muffled hearing for several hours after exposure.
How loud is too loud? The loudness of sound is measured in decibels (dB). Noise-induced hearing impairment can be caused by prolonged exposure to any noise over 85 dB. The infographic below shows the loudness levels of common sounds.