noise coming from outside.
             What is the most pervasive environmental noise source and how many people are exposed to it?
             Urban traffic is by far the most pervasive outdoor residential noise source, although aircraft noise is a significant source as well. Over 96 million persons are estimated to be exposed, in and around their homes, to undesirably high traffic noise levels exceeding 55 dB. But traffic is not the only problem here, heaters, factories, hospitals ,police stations, night clubs and almost every place made for congregate people. The noise comes from many places and forms. There is noises that people do not classify them as noises and them are not bothering everybody. Here like in many other environmental issues ther is also a question of minorities. Many people that is complaining all the time about the traffic noise go to work by car and they are not the right people to complaint about it. Talking about sound pollution is hard to canalizes all the complaints in one channel.
             The people exposed to noise,workers and non-workers.
             Not just the people who is working suffer this pain, also people that try to sleep or to rest are suffering this problem. What about us the students, sometimes every week we need a quiet place where concentrate in our studies without noise. An estimated 15 million American workers are exposed to 75 dB or above which may be hazardous to their hearing. Because of tie overlap between persons in occupational and non-occupational noise exposure situations, there is an estimated total of 20 to 25 million persons, just in the states could may possibly incur in hearing losses . If we start talking about hearing losses we better take this subject into consideration. Is Important, is about health.
             It is a fact that we can loss some power of hearing because of the noise but how? My last desire is to sound like a diccionary but this is how exactly our ear reacts to the external noise.
             The outer e...