Noise Pollution can define as an unpleasant and unwanted sound. We hear various types of sound every day. Sound is mechanical energy from a vibrating source. After, Air Pollution maybe you’ll like to know another Pollution. If yes? So, this article explains about Noise Pollution, and their topics – sources, effects, and control. A type of sound may be pleasant to someone and at the same time unpleasant to others. The unpleasant and unwanted sound is called noise. Sound can propagate through a medium like air, liquid or solid.
Here is article explains the Noise Pollution and their topics; Sources, Effects, and Control.
The sound wave is a pressure perturbation in the medium through which sound travels. Sound pressure alternately causes compression and rarefaction. The number of compressions and rarefactions of the molecules of the medium (for example air) in a unit time is described as frequency. It is expressed in Hertz (Hz) and is equal to the number of cycles per second.
There is a wide range of sound pressures, which encounter the human ear. An increase in sound pressure does not invoke the linear response of the human ear. A meaningful logarithmic scale has been devised. The noise measurements are expressed as Sound Pressure Level (SPL) which is the logarithmic ratio of the sound pressure to a reference pressure.
It is expressed as a dimensionless unit, a decibel (dB). The international reference pressure of 2 x 10-5 Pa is the average threshold of hearing for a healthy ear. The decibel scale is a measure of loudness. Noise can affect the human ear because of its loudness and frequency (pitch). The Central Pollution Control Board (CPCB) committee has recommended permissible noise levels for different locations as given in Table;
Sources of Noise Pollution:
The main sources of noise are various modes of transportation (like air, road, rail-transportation), industrial operations, construction activities and celebrations (social/religious functions, elections, etc) electric home appliances. High levels of noise have been recorded in some of the cities of the world. In Nanjing (China) noise level of 105 dB has been recorded, while in some other cities of the world these levels are: Rome 90 dB, New York 88 dB, Calcutta 85 dB, Mumbai 82 dB, Delhi 80 dB, Kathmandu 75 dB.
Major causes/sources of noise pollution are:
Progress in technology (industrialization) has resulted in creating noise pollution. Textile mills, printing presses, engineering establishments, and metal works, etc. contribute heavily to noise pollution.
These operate from workshops located on the ground floors of the residential areas and cause annoyance, discomfort, and irritation to the residents exposed to the noise that is inevitably produced.
For example, the situation is much better in modern planned cities like Chandigarh where the industrial area is kept away from the residential areas and both are separated from each other by a sufficiently wide green belt.
2] Automobile or Transport Vehicles:
The automobile revolution in urban centers has proved to be a big source of noise pollution. Increasing traffic has given rise to traffic jams in congested areas where the repeated hooting of horns by impatient drivers pierce the ears of all road users.
Noise from airplanes constitutes an increasingly serious problem in big cities like Delhi & Mumbai. Airport situated in the vicinity of population centers and airplanes pass over residential areas. Heavy trucks, buses trains, jet-planes, motor-cycles, scooters, mopeds, jeeps—the list of vehicles is endless but the outcome is the same — noise pollution.
The household is an industry in itself and is a source of many indoor noises such as the banging of doors, noise of playing children, crying of infants, moving of furniture, a loud conversation of the inhabitants, etc. Besides these are the entertainment equipment in the house, namely the radio, record-players, and television sets. Domestic gadgets like the mixer-grinders, pressure cookers, desert coolers, air- conditioners, exhaust fans, vacuum cleaners, sewing and washing machines are all indoor sources of noise pollution.
4] Public Address System:
In India, people need only the slightest of an excuse for using loudspeakers. The reason may be a religious function, birth, death, marriage, elections, demonstration, or just commercial advertising. The public system, therefore, contributes in its way towards noise pollution.
5] Agricultural Machines:
In modern times, agriculture is highly changing in food farming. They also use modern technic or machines for farming growth. In Tractors, thrashers, harvesters, tube wells, powered tillers, etc. have all made agriculture highly mechanical but at the same time highly noisy. Noise level 90 dB to 98 dB due to the running of farm machines have been recorded in the state of Punjab.
6] Defense Equipment:
We talk about Noise pollution, so we can not forget Defense Equipment or security level sources. Defense Equipment is one of them, We have defense tools to protect the country from outside countries. In every country, they manufacture more and more defense equipment for the protection of the countrymen.
A lot of noise pollution adds to the atmosphere by artillery, tanks, launching of rockets, explosions, exercising of military airplanes and shooting practices. Screams of jet engines and sonic booms have a deafening impact on the ears and in extreme cases have been known to shatter the window panes and old dilapidated buildings.
Effects of Noise pollution:
Noise pollution causes the following effects.
- Interferes with man’s communication: In a noisy area, communication severely affects.
- Hearing damage: Noise can cause temporary or permanent hearing loss. It depends on the intensity and duration of the sound level. Auditory sensitivity reduces with a noise level of over 90 dB in the mid-high frequency for more than a few minutes.
- Physiological and Psychological changes: Continuous exposure to noise affects the functioning of various systems of the body. It may result in hypertension, insomnia (sleeplessness), gastrointestinal and digestive disorders, peptic ulcers, blood pressure changes, behavioral changes, emotional changes, etc.
Effects or Impacts of Noise Pollution – diagram:
Noise is generally harmful and a serious health hazard. It has far-reaching consequences and has many physical, physiological as well as psychological effects on human beings. Extra things:
1] Physical Effects:
The physical manifestation of noise pollution is the effect on hearing ability. Repeated exposure to noise may result in temporary or permanent shifting of the hearing threshold of a person depending upon the level and duration of exposure.
The immediate and acute effect of noise pollution is the impairment of hearing (i.e. total deafness). Human ears have sensory cells for hearing. If these cells are subjected to repeated sounds of high intensity before they have an opportunity to recover fully.
They can become permanently damaged leading to impairment of hearing. In addition to sensory cells, delicate tympanic membranes or eardrums can also permanently harm by sudden loud noises such as an explosion.
2] Physiological Effects:
Physiologica means, relating to the branch of biology that deals with the normal functions of living organisms and their parts. The physiological manifestations of noise pollution are several as mentioned below:
- Headache by dilating blood vessels of the brain.
- Increase in the rate of heart-beat.
- Narrowing of arteries.
- Fluctuations in the arterial blood pressure by increasing the level of cholesterol in the blood.
- The decrease in heat output.
- Pain in the heart.
- Digestive spasms through anxiety and dilation of the pupil of the eye, thereby causing eye-strain.
- Impairment of night vision.
- The decrease in the rate of color perception.
- Lowering of concentration and effect on memory.
- Muscular strain and nervous breakdown, and.
- Psychological Effect.
Control of Noise Pollution:
How to control noise pollution? If we do something controlling noise or extra sound out there. So, what they are? The following controlling things below are;
Reduction in sources of noise:
- Sources of noise pollution like heavy vehicles and old vehicles may not allow driving in populated areas if they follow as also control some noise.
- Noise making machines should keep in containers with sound-absorbing media. The noise path will interrupt and will not reach the workers.
- Proper oiling will reduce the noise from the machinery.
Use of sound-absorbing silencers:
- Silencers can reduce noise by absorbing sound. For this purpose, various types of fibrous material could use.
- Planting more trees having broad leaves.
Through Law: Legislation can ensure that sound production is minimized at various social functions. Unnecessary horn blowing should restrict especially in vehicle-congested areas.