Approximately 37 million people over age 18 report some degree of hearing loss, and twice as many men as women between ages 20-69 have hearing loss. About 25 million Americans also report tinnitus, or ringing in the ears. The most common type of hearing loss is age-related loss, but of those 37 million people, about 26 million of those have noise-induced hearing loss.
What is noise-induced hearing loss? This is damage to your hearing caused by any type of loud noise, be it sudden like a gunshot or fireworks, or of longer duration, such as daily exposure to loud noise. When an excessive sound energy hits the inner ear, damage occurs in the inner ear, causing hearing loss. Sometimes this is brief, such as after a rock concert, and can be reversible. However, noise damage is cumulative - it continues to build after repeated exposure. When this occurs, damage to the ears, and hearing loss, can be severe, as well as permanent. While age-related hearing loss happens slowly over time, hearing loss caused by noise exposure can be very rapid, and sometimes instantaneous. When a blast injury occurs - such as exposure to a gunshot - damage is instant, usually permanent, and if accompanied by dizziness, may require surgical intervention to determine if a hole has opened in the inner ear.
OSHA requires hearing protection when exposed to noise for 8 hours at levels of 90 dB, and after only 2 hours at levels of 100 dB. While we know the damage noise can cause to our hearing, other little-known effects include increases in blood pressure and heart rate, increased stomach acid, increased stress levels, anxiety and irritability, as well as reduced job performance.
Below are listed the sound levels of various sounds in our environment, as well as noise:
Faintest sound heard by human ear: 0 dB
Whisper, quiet library: 30 dB
Normal conversation, sewing machine, typewriter: 60 dB
Lawnmower, shop tools, truck traffic: 90 dB
Chainsaw, pneumatic drill, snowmobile: 100 dB
Sandblasting, loud rock concert, auto horn: 115 dB
Gun muzzle blast, jet engine (such noise can cause pain and even brief exposure injures unprotected ears): 149 dB
If you have to shout to be heard over the noise levels, if exposure causes ear pain, ringing, or you notice hearing loss, the noise is most likely damaging your ears. Other factors that may affect your susceptibility to noise damage are light colored eyes or skin, diabetes, Meniere’s disease, smoking, atherosclerosis (hardening of the arteries), and iron or vitamin A deficiencies.
Protect yourself from noise exposure by wearing proper hearing protection, reducing the noise level if possible, or removing yourself from the noise. Protect children’s ears by having them wear earmuffs, and be alert to the possibility of hazardous noise around you. And as we always recommend, have your hearing tested by an audiologist if you feel you’ve suffered damage to your hearing due to noise exposure.