WBBSE Class 6 Geography Chapter 9 Noise Pollution Introduction
1. When sounds become intolerable, painful, and irritable to human beings, it produces noise pollution.
2. Sounds that do not cause any type of physical or mental discomfort to human beings or other animals are known as musical sounds.
3. Unit for measuring the intensity of sound is called decibel (dB).
4. The instrument used to measure the intensity of sound is called a decibel meter.
Read and Learn More WBBSE Class 6 Geography Notes
5. A board depicting special signs used to control noise pollution and warn the people is known as a Silence Board.
6. A Silence Board is hung near schools, hospitals, and other institutions. This means that it is legally forbidden to blow horns near these institutions.
7. The highest level of sound that human ears can tolerate is 65 decibels. This value is also designated by WHO as the safe decibel level.
8. The main sources of noise pollution are vehicular traffic and industrial plants.
9. Noise pollution can cause irritation, loss of hearing, headache, and other ailments to human beings.