28-03-2011, 11:54 AM
PRESENTED BY:
sk.rameeza
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Introduction
The Noise Pollution is something that has existed since a long time ago. Now it begins to produce its effects. We can’t ignore the problem but deal with studying and trying to look for solutions in order to avoid that it increase and decrease everyone more and more, that why we must work together without self interest because at the end it is not only the country or continent that is suffering but also the world in which we live in.
What is Noise Pollution ?
In simple words the Noise Pollution can be defined like the excess of sound that disrupts the normal conditions of the environment in a certain area.
Sounds are considered noise pollution if they adversely affect wildlife, human activity, or are capable of damaging physical structures on a regular, repeating basis. In the broadest sense of the term, a sound may be considered noise pollution if it disturbs any natural process or causes human harm, even if the sound does not occur on a regular basis.
What is Decibel (dB) ?
The decibel (dB) is a measure of sound intensity; that is, the magnitude of the fluctuations in air pressure caused by sound waves. The decibel scale is logarithmic, not arithmetic. This means that a doubling of sound intensity is not represented as a doubling of the decibel level. Decibels are usually measured with a filter that emphasizes sounds in certain frequencies.
• Human hearing
MACHANISMS
• Physical characteristics
• Psychophysics:
• objective and quantitative study of the relation of physical stimuli and sensory perceptions
Structure of the human ear
Effects Of Noise On Humans
a) Auditory effects interfering with hearing; auditory fatigue and deafness.
b) Non-auditory effects interfering with social behaviour
c) Physiological effects affecting biological functions
d) Endocrine and hormonal changes relating to stress and noise levels. i.e. raised adrenaline and cholesterol.
e) Psychological effects; physical and mental fatigue, loss of concentration, lower efficiency……………..
Cardiovascular effects
Noise has been associated with important cardiovascular health problems. In 1999, the World Health Organization concluded that the available evidence showed suggested a weak association between long-term noise exposure above 67-70 dB(A) and hypertension. More recent studies have suggested that noise levels of 50 dB(A) at night may also increase the risk of myocardial infarction by chronically elevating cortisol production
Possible Solutions
• Auditory personalized protection
• Absorbent materials
• Acoustics barriers
• Isolations
• Sheds Sonomuffled
