Thursday December 19th 2013
Noise is a prominent part of our society and causes significant damage to our ears as well as increasing a risk of cardiovascular diseases. The field of environmental noise works to study what devices create the most noise and how we can reduce that noise to therefore reduce the harm done to humans. An increase in the intensity of a noise is the increase in the energy in its sound waves, and if this energy gets to a certain point it creates damage in the humans ear (70 dB). There are approximately 40 million people who have hearing loss in America and a fourth of these people are having hearing loss because of noise intensity. The damage is done specifically to the different sized hairs in the concha in the human ear, not allowing them to transmit high and low pressure vibrations to the nervous system through electrical signals. Another proven problem that noise causes is stress by stimulating the autonomous nervous system and the endocrine system. There have been studies that prove that increased and constant exposure to loud noise increases the chance of getting cardiovascular diseases such as angina, hypertension (high blood pressure) and strokes. Exposure to noise less than 70 dB does no damage to the human ear and the average conversation occurs at 60 dB. You would expect elderly people to be the only age group to have impaired hearing yet 16% of the 35,151 people surveyed aged 6-18 are impaired in both ears. This is most likely because of the many everyday devices that are above this the 70 dB level. A bulldozer idling produces 85 dB of sound and although this may not seem very high over 70 dB, studies show that just 8 hours (one day at work) can cause permanent damage. Knowing that, it is shocking to hear that headphones can reach to a level of 100 dB. They can cause permanent damage after just 15 minutes per day. Furthermore, a gunshot can cause immediate damage reaching up to 140-190...
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