Noise Induced Hearing Loss – What is It?
Noise induced hearing loss is the loss of hearing caused by exposure to loud noises. Tiny hairs inside the ear turn vibrations (noise) into signals that the brain processes. Loud noise hurts these tiny hairs and damages their effectiveness. Next to age-related hearing loss, noise induced hearing loss is the leading cause of hearing loss. In fact, the Centers for Disease Control and Prevention (“CDC”) estimates that 5.2 million American children (12.5% of American children) have already suffered permanent hearing loss from exposure to loud noise.
Noise Induced Hearing Loss Can Be Temporary or Permanent
If the noise is loud enough and the exposure long enough, the noise can kill the hair cell – permanently lessening hearing ability. This is permanent noise induced hearing loss. For example, a momentary sound blast from a cordless telephone of about 140dB has caused permanent hearing loss. In scientific terms, the DNA of the hair cells becomes damaged by oxidation, causing cell death.
In contrast, if the exposure to noise only damages the hair cells, the resulting hearing loss is temporary, and the lost hearing will return.
Noise Induced Hearing Loss is Irreversible But Preventable
If the noise exposure kills the hair cell, the resulting hearing loss is permanent and thus irreversible. There is no treatment that result in the recovery of the lost hearing.
The hearing loss typically first occurs at higher sound frequencies (about 4,000 Hz). Hearing loss thereafter progresses down to lower frequencies. Because the hearing loss occurs first at higher frequencies, the person does not readily notice it. Therefore, the person continues to receive exposure to the damaging loud noise.
However, noise induced hearing loss is preventable. One can prevent noise induced hearing loss by avoiding very loud noises or prolonged exposure to less loud noises. Wearing ear protection, such as ear plugs or noise reducing ear muffs, can mitigate the damaging effect loud noises would otherwise have.
People that protect themselves from noise induced hearing loss will likely have better hearing as they age then people that do not protect themselves.