Noise induced hearing loss (NIHL) is the complete or partial loss of hearing that occurs as a result of loud noises. Noise induced hearing loss can occur suddenly as the result of exposure to a one-time loud sound, such as an explosion, or can occur over time with routine exposure to loud sounds. Though noise induced hearing loss caused by impulse sound can result in immediate loss of hearing, it may or may not be permanent. However, noise induced hearing loss that occurs over time is often permanent. It is estimated that out of the roughly 30 million Americans with some degree of hearing loss, one-third are suffering completely or partially from noise induced hearing loss.
NIHL is the result of damage to the inner ear caused by loud sound. The inner ear is comprised partly of sensitive nerves and hairs as well as tiny bones, all of which work together to translate sound wave vibrations into audible sounds distinguishable by the brain. When the inner ear becomes damaged, sounds can become muffled or completely blocked.
All sound is measured in decibels. Normal levels of sound, such as conversation, do not cause noise induced hearing loss. Typically, sounds of less than 80 to 90 decibels, even with prolonged exposure, do not cause damage to the inner ear. However, loud sounds in excess of 100 decibels, especially after prolonged exposure, can cause NIHL.
The most frequent sources of sounds that can cause noise induced hearing loss are work and hobby related. People who work around construction equipment such as power tools and heavy machinery are at risk of noise induced hearing loss. Other potentially harmful sounds include racecars, firearms, and loud music. The best way to reduce the risk of noise induced hearing loss is to protect the inner ear in situations where prolonged exposure to loud sound is unavoidable.
Wearing earplugs or earmuffs is one way to protect your ears and reduce the risk of noise induced hearing loss. Be aware of noises that are potentially harmful to the ear and avoid them when possible. Protect younger children from potentially damaging sounds and encourage them to play music, especially on headphones or earbuds at a reasonable level.
Be aware that many people with noise induced hearing loss are not aware it has affected them because NIHL often occurs over time. Schedule routine hearing tests with your physician or an audiologist to monitor your hearing abilities. Having NIHL identified early can prevent hearing impairment later in life.