[Physics Class Notes] on Noise Pollution Prevention Pdf for Exam

Noise Pollution 

The word or term noise is derived from a Latin word ‘Nausea’ which generally means sickness in which one feels like vomiting. The term Noise is the unpleasant and undesirable sound which leads to discomfort in human beings. The intensity of sound is measured in decibels, denoted by dB. The faintest that we can say is the lowest sound which can be heard by the Human ear is 1 Db. Due to increasing noise around the civilizations, noise pollution which has become a matter of concern. Some of its major causes are vehicles, aircraft, industrial machines, loudspeakers, crackers, etc. We can also see that some other appliances also contribute to noise pollution like television, transistor, radio, etc. when they are generally played at high volume.

Hazards of Noise Pollution

The term noise pollution can be hazardous for the to human health in the following ways give below:

It is a direct result of noise pollution caused due to elevated levels of blood for a longer duration.

The constant the exposure of human ears to loud noise that is beyond the range of sound that human ears can withstand damages the eardrums resulting in loss of hearing.

Lack of sleep might result in fatigue and low energy levels throughout the day affecting everyday activities. Noise pollution hampers the sleep cycles leading to irritation and uncomfortable state of mind.

Heart-related problems such as an increase in the level of the blood pressure and stress and cardiovascular diseases might occur in a normal person and a person suffering from any of these diseases that might feel the sudden shoot up in the level.

Causes of Noise Pollution

It is said that it mainly consists of the traffic noise which has increased in recent years with the increase in the number of vehicles. The increase in noise pollution generally leads to deafening in older people or headache, hypertension, etc. The noise from gadgets and household utensils etc. are some of the main sources along with musical instruments and the transistors, loudspeakers and the sound caused by heavy industrial machines. Note that according to many researchers, industrial noise pollution which damages the hearing ability to around 20%. The following are the causes and sources of noise pollution:

• Process of Industrialisation: Industrialisation process has led to an increase in noise pollution as the use of heavy machinery such as generators, mills, huge exhaust fans is prominent, usually resulting in the production of unwanted noise.

• Traffic Vehicles: the increased number of vehicles on the roads are the second reason for noise pollution.

• Events such as weddings, then the public gatherings involve loudspeakers to play music resulting in the production of unwanted noise in the neighbourhood.

• Construction sites: the area of mining and the construction of buildings etc are said to add to the noise pollution.

The following are examples of noise pollution:

• Unnecessary usage of horns.

• Using loudspeakers either for religious functions or for political purposes.

• Unnecessary usage of fireworks.

• Industrial noise.

• Construction noise.

• Noise from transportation such as railway and aircraft.

Noise Pollution Control

There are some of the noise pollution preventive measures provided in the points below.

• Honking in public places like teaching institutes that are the hospitals, etc. should be banned.

• In hospitals and industrial buildings, adequate soundproof systems should be installed.

• Musical instruments’ sound should be controlled to desirable limits.

• The dense cover of the trees is useful in noise pollution prevention.

• Explosives should be not used in forest, mountainous, and mining areas.

An excessive sound can have deleterious effects on human health and wildlife, and environmental quality. Noise pollution is commonly generated inside many industrial facilities and some other workplaces but it also comes from highway railway and airplane traffic and from outdoor construction activities.

Noise Pollution Control Measures

The waves of sound are vibrations of the molecules of the air carried from a noise source to the ear. The term sound is typically described in terms of the loudness the amplitude and the pitch the frequency of the wave. Loudness, also known as the sound pressure level, or SPL which is measured in logarithmic units called decibels. The normal human ear can detect the sounds that range between 0 dB of hearing threshold and about 140 dB with sounds between 120dB and 140 dB causing pain. The ambient SPL in a library is about 35 dB while that inside a moving bus or we can say the subway train is roughly 85 dB. The construction of buildings can generate SPLs as high as 105 dB at the source. The SPLs decrease with distance from the source.

The rate at which the energy of the sound is transmitted known as the sound intensity and is proportional to the square of the SPL. This is because of the logarithmic nature of the decibel scale an increase of 10 dB represents a 10-fold increase in sound intensity an increase of 20 dB represents a 100-fold increase in intensity a 30-dB increase represents a 1,000-fold increase in intensity and so on. When the sound intensity is doubled, the SPL increases by only 3 dB.