Noise-induced Hearing Loss -How to Prevent It

The human ear can hear sounds ranging in frequency from 20 Hertz (Hz.) to 20000 Hz. Sounds above 20000 Hz. and below 20 Hz. are inaudible to the human ear. Most human cultures have developed languages that are aural-oral in nature. Hence, the sense of hearing becomes very important for communication in these languages.

In the English language, speech sounds range between 500 Hz. and 6000 Hz. Even a mild hearing loss in any part of this frequency spectrum, will result in an impairment of the expression and the reception of the oral language. When one's expressive and receptive language is impaired, one's social, educational an emotional development may be undermined.

In the discipline of audiology, a hearing loss refers to all levels of impairments. Hearing levels are measured in decibels (dB) across the frequencies 125 to 8000 Hz. Persons with normal hearing will hear sounds in these frequencies starting with an intensity between 0 and 26dB. When a person's hearing threshold rises beyond 26dB, then a hearing loss is indicated. There are five categories of hearing impairments, 27-40dB mild; 41-55dB moderate; 56-70dB severe; 90dB and over, profound. When noise is found to be the cause of a hearing impairment, the person is said to have a noise-induced hearing loss.

During the industrial revolution, when factories of all kinds were springing up across the nations of Europe and North America, workers were exposed to noisy work conditions. Many workers in those factories lost their hearing as a result of the excessive noise they endured. Today, laws have been enacted in those countries to protect workers from noise. These laws have gone a long way in eliminating noise-induced hearing loss in the workplace. Despite this, many individuals continue to subject themselves and others to loud noises on a regular basis. Of the more than 28 million Americans who have a hearing impairment, a third of them have in some way attributed their impairment to excessive noise.

Persons who are exposed to noise levels 85dB and over are certain to incur a hearing loss after some time. An exposure to a noise level of 90dB will produce a permanent hearing loss in a much shorter time than the exposure at 85dB. In other words, the higher the noise level and the longer the exposure, the greater the increase of the rate at which the damage is done to the hearing mechanism.

Noise-induced hearing loss is insidious. The loss occurs in such a way that it is not noticed until the damage is already done. Hearing loss caused by noise first impairs the person's ability to hear sounds around 6000Hz. A person so affected, may still be able to hear the majority of speech sounds, but will have problems understanding a normal conversation. As the impairment progresses, the ability to understand a conversation will continue to deteriorate. Eventually the person may have to wear a hearing aid to assist him in hearing normal speech.

There are several useful tools found around the home that produce noise above the 85dB level. Included in are lawnmowers, chain saws, jackhammers, generators, power saws and other power tools, hedge trimmers, stereos and music systems. When using these and other noisy equipment, care must be taken to avoid direct exposure to the noise they emit.

Preventing Noise Induced Hearing Loss

1.Wear earplugs or earmuffs when operating noisy machinery.

2.Turn down the volume on loud music.

3.Stay away from any source of loud noise if possible.

4.House noisy machinery in enclosures that minimize the noise on the outside.

5.Mount noisy equipment on rubber mats to reduce the noise level.

Always remember that a noise is too loud when it interferes with the conduct of a normal conversation. Your hearing is important. It allows for effective communication and social interactions on all levels. It contributes immensely to the ability to enjoy music, movies, the wonderful sounds of nature, friends and family. Do not let noise ruin your hearing that you can no longer enjoy the best things that life has to offer. Take control of the noise in your environment and conserve your hearing.