Page 93 - Viva ICSE Science 5 : E-book

Sirens are generally provided to emergency vehicles. Sirens of diff erent emergency
vehicles have diff erent sounds.

Noise Pollution

Any loud and unpleasant sound is called noise. When noise becomes so excessive that

it causes disturbance to the health of living beings, it is called noise pollution. It is harmful
not only for human beings but also for animals.

Causes of noise pollution

• Machines in factories and industries make a lot of noise. It disturbs the people and
animals living in the nearby area.

• Certain construction activities like making roads, fl yovers and buildings cause
disturbance to people of that area.

• Movement of vehicles like cars, buses, trains and
aeroplanes (during landing and takeoff ) produce
disturbing noise. Excessive honking from vehicles

contributes to noise pollution.
• Loud noise produced by bursting crackers also cause

noise pollution.

• Use of loud speakers, listening to loud music and noise created by the use of electrical
appliances at home also add to noise pollution.

Harmful eff ects of noise pollution

Noise pollution has harmful eff ects on the physical and mental health of living beings.

• Constant loud noise leads to lack of sleep. This makes a person
tired and restless.

• It gives rise to health problems like headache, irritation,
hypertension and stress.

• Concentration level of people decreases, which has bad eff ect
on the work they do.
Did You Know!
• Noise pollution can cause temporary or permanent
Sound is measured in
deafness.
decibels (db). A sound level
• People cannot talk to each other during loud noise. It more than 80–100 db is
harmful for our ears.
causes disturbance.

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