How Loud Is Too Loud?
Both the amount of noise and the length of time you are exposed to it determine its potential to damage your hearing. Noise levels are measured in decibels (dB). The higher the decibel level the louder the noise.
Standards set by OSHA (Occupational Safety and Health Administration) indicate that continued exposure of unprotected ears to noise over 90 dB will cause a gradual hearing loss in a significant number of individuals. Louder noises will accelerate this damage. The allowed exposure time decreases by ONE - HALF for each 5 dB increase in the average noise level.
How Does Damage Occur?
As mentioned earlier, sound is converted from an airborne vibration to wavelike fluid motion in the inner ear. The motion of the fluid in the cochlea stimulates the hair cells that send electrical impulses to the brain.
It may be helpful to think of the hair cells in the inner ear as reeds in a pond. On a calm day with the wind blowing lightly the reeds sway back and forth in the breeze. On a stormy day the wind blows so hard that the reeds in the pond are forced down flat. Depending on the length or severity of the storm, a number of these reeds will gradually return to their normal condition, but others will have been broken and will not recover.
Repeated exposure to loud noise fatigues the hair cells in the inner ear. Just like the reeds, some of these hair cells will return to the normal position, but others will have been damaged beyond the point of recovery. The destruction of these hair cells is evidenced by permanent hearing loss.
Noise induced hearing loss typically occurs gradually and without pain. Often by the time a person realizes that there may be a problem, it is too late. But there are early warning signs.
If you experience any of the following symptoms, have your hearing tested by a Hearing Health Care Professional:
- A ringing or buzzing (tinnitus) in the ear immediately after exposure to noise.
- A slight muffling of sounds after exposure, making it difficult to understand people after you leave a noisy area.
- Difficulty understanding speech; that is, you can hear all the words, but you can't understand all of them.
Are You At Risk?
Be aware of the warning signs for hearing loss. If you have control of the volume, turn it down; if you don't, wear hearing protection.
There are many options available today to meet specific needs and uses for hearing protection; from products designed to give as much ambient noise protection as possible, to hearing protection devices designed specifically for performing musicians.
Twenty years ago no one wore bicycle helmets, now it's rare when you see someone riding without one. Concrete hasn't gotten harder in the last two decades, people have become much more educated about the risks involved and the dangers they face should they be involved in an accident.
It's a noisy world out there. With the information and resources available today, positive steps can be taken to reduce the occurrence of noise-induced hearing loss.