Noise Pollution.pptx 1

8/10/2019 Noise Pollution.pptx 1

1/36

Noise Pollution


2/36

WHAT IS NOISE POLLUTION?

Sound that is unwanted or disrupts ones quality of lifeis called as noise. When there is lot of noise in theenvironment, it is termed as noise pollution.

Sound becomes undesirable when it disturbs thenormal activities such as working, sleeping, and duringconversations.

It is an underrated environmental problem because ofthe fact that we cant see, smell, or taste it.

World Health Organization stated that Noise must berecognized as a major threat to human well- being


3/36


4/36

Noise Pollution: Sources and Types

It is broadly divided into two parts:

IndustrialNon-Industrial Noise
http://rashidfaridi.com/2013/03/19/noise-pollution-sources-and-types/http://rashidfaridi.com/2013/03/19/noise-pollution-sources-and-types/http://rashidfaridi.com/2013/03/19/noise-pollution-sources-and-types/http://rashidfaridi.com/2013/03/19/noise-pollution-sources-and-types/


5/36

Industrial Noise Noise produced by industries is called IndustrialNoise. In general it is produced, at every stage in

industry by various aspects like welding,hammering, drilling, blowing, running machinery,motors, sheet metal work, lathe machine work,

operation of cranes, grinding, turning, riveting,fabricating, forging, compressing, vaccumising,breaking, moulding, steaming, boiling, cooling,heating, venting, painting, pumping, packing,

transporting etc. It creates very serious of large-scale noise problems; significantly affect theworking people as well as surrounding people.


6/36

Non Industrial Noise Further types of non-industrial-noise Road Traffic Noise

Rail Traffic Noise Aircraft Noise Residential & Community Noise


7/36

Road Traffic NoiseRoad traffic is the most widespread source of noise

in all countries and the most prevalent cause ofannoyance and interference. It is directly

proportional to the volume of vehicles. Increasingof population is increasing of vehicles and hence

increasing of Noise pollution. The major sources ofnoise in automobiles are exhaust, intake, engine

and fan, and tires at high speed. The noise outputof all components increases with speed. As anexample, keeping all the conditions same, an

approximately 10 dB (A) increase with speed of acar from 30mph to 60mph.


8/36

Road Conditions

Traffic Clearance

Condition of Vehicles

Speed of the Vehicle

The Road traffic noise not only depends onvolume of vehicles and also depends on

several factors, some of them are below:


9/36

Rail Traffic Noise Noise from the trains includes 1) diesel Exhaust 2)Engine and Air Intake 3) Cooling Fans 4) Wheel-railinteraction 5) Electric generator and electric traction

motor 6) miscellaneous noise generated in freight andpassenger cars etc. Other intermittent noises includes

car impact sounds when trains are braking andaccelerating and the sounds of sirens or horns that

produces 10 to 20 dB (A) higher than from othersources. The noise generated in communities having

long haul or rapid transit vehicles (like Metros) in their

environment will depend primarily on track observerdistance, frequency and train length and condition oftrack. The rapid transit trains are short, so that theirnoise duration time is much less than that of goodstrains. Rapid transit vehicles produce lower level of

noise than compare to lengthy trains.


10/36


11/36

Aircraft Noise Noise from commercial aircraft is only a problem

around airports as this is where aircraft converge atlow altitude and high engine power. Increasing airtraffic with different types of aircrafts and cityexpansion will exacerbate the noise problems. Noisepollution of an aircraft will increase with the speed.The aircraft noise reduction; traffic and flight pathrestrictions can alleviate them.

The invention of supersonic aircrafts has added more

noise for the plight of persons who live nearaerodromes. Taking off and landing of an aircraftproduces unbearable noise.


12/36


13/36

Residential & Community Noise In normal day to day activities, various home appliances

in our residences produce noise. Some of the major sourcesare Exhaust Fans, lawn movers, mixis, grinders, Fan, Cooling& Heating System, T.V & Music System, motors used forpumping etc.

Community noise is one of the major sources for affecting alarge number of people living within the community. Itoccurs due to various activities of community duringreligious festivals, fairs, marriages, or public functions. Theuse of amplifiers provides one of most frequent sources ofdisturbances. Loudspeaker systems are in almost continualuse at many open-air events


14/36

Impacts of Noise


15/36

Noise is defined as unwanted sound .

Noise pollution makes men more irritable.

The effect of noise pollution is multifaceted &inter related.

The impacts of noise on human being, animaland property are as follows.


16/36

16

(1) It decreases the efficiency of a man

Regarding the impact of noise on humanefficiency, there are number of experimentswhich point out the fact that human efficiencyincreases with noise reduction.

Thus human efficiency is related with noise.

Impact of noise on human


17/36

PH 0101 UNIT 1 LECTURE 9 17

(2) Lack of Concentration

For better quality of work there should beconcentration.

Noise causes lack of concentration.

In big cities, mostly all the offices are on mainroad, the noise of traffic or the loud speakers ofdifferent types of horns divert the attention ofthe people working in offices.


18/36


(3) Fatigue

Because of noise pollution, people cannotconcentrate on their work.

Thus they have to give their more time forcompleting the work and they feel tiring


19/36


(5) It causes Blood Pressure

Noise pollution causes certain diseases in human. It attacks on the persons peace of mind. The

noises are recognized as major contributingfactors in accelerating the already existingtensions of modern living.

The tensions result in certain disease like bloodpressure or mental illness etc.


20/36


(6)Temporary or Permanent Deafness

The effect of noise on audition is well recognizedin Mechanics, locomotive drivers, telephoneoperators etc.

All have their hearing impairment as a result ofnoise at the place of work.

Physicist, physicians & psychologists are of theview that continued exposure to noise level above80 to 100 dB is unsafe.

Loud noise causes temporary or permanentdeafness.


21/36


Impact of Noise on Animals

Noise pollution damage the nervous system ofanimals.

Animal looses the control of its mind.

They become dangerous.


22/36


Control of Noise Pollution

The techniques employed for noise control can bebroadly classified as

(1) Control at source(2) Control in the transmission path .


23/36


(a) Reducing the noise levels from domesticsectors

The domestic noise coming from radio, taperecorders, television sets, mixers, washingmachines, cooking operations can beminimized by their selective and judiciousoperation.


24/36


(b) Maintenance of automobiles

Regular servicing and tuning of vehicles will

reduce the noise levels.

Fixing of silencers to automobiles.


25/36


(c) Control over vibrations The vibrations of materials may be controlled

using proper foundations, rubber padding etc., toreduce the noise levels caused by vibrations.


26/36


(d) Low voice speaking

Speaking at low voices enough forcommunication reduces the excess noise levels.


27/36


(e)Prohibition on usage ofloud speakers

By not permitting the usage of loudspeakers inthe habitant zones except for important meetingsor functions.


28/36


(f) Selection of machinery

Optimum selection of machinery tools orequipment reduces excess noise levels.

For example selection of chairs, or selection ofcertain machinery / equipment which generate

less noise (sound) due to its superior technology.


29/36


(g) Maintenance of machines

Proper lubrication and maintenance of machines,vehicles etc., will reduce noise levels.

For example, it is a common experience that,many parts of a vehicle will become loose whileon a rugged path of journey.

If these loose parts are not properly fitted, theywill generate noise and cause irritation to thedriver/passenger.


30/36


(2) Control in the transmission path

The change in the transmission path will increase thelength of travel for the wave and getabsorbed/refracted/radiated in the surrounding

environment.The available techniques are:(a) Installation of barriers (b) Installation of panels

(c) Green belt development


31/36


(a) Installation of barriers

Installation of barriers between noise source and receivercan attenuate the noise levels.

The barrier may be either close to the source or receiversubjected .


32/36


R D

SourceReceiverBarrier

Barrier close to source


33/36


D

Barrier

Receiver

Source

R

Barrier close to receiver


34/36


(b) Installation of panels or enclosures

A sound source may be enclosed with a paneledstructure such as room as a means of reducing the noiselevels at the receiver.

The actual difference between the sound pressure levelsinside and outside an enclosure depends not only on thetransmission loss of the enclosure panels but also on the

acoustic absorption within the enclosure and the detailsof the panel penetrations which may include windows ordoors.


35/36


(c) Green Belt Development

Green belt development can reduce the soundlevels.

The degree of reduction varies with species ofgreenbelt.

The legal regulations direct the industries to

develop greenbelt four times the built-up areafor attenuation of various atmosphericpollutants, including noise.


36/36

Documents

Noise Pollution.pptx 1