Noise Pollution

• It is a loud and unpleasant sound created by people or machines that can cause discomfort.
• Noise is loud, annoying, distracting, intrusive, and physically painful.
• The noise sources could be road traffic, jet planes, garbage trucks, construction equipment, manufacturing processes, leaf blowers, and boom boxes.
• The intensity of sound is measured in decibels (dB).
• If the sound intensity is increased by about 10 dB, it will double the increase in loudness.
• According to WHO (World Health Organization), a person's hearing can be damaged if exposed to noise levels over 75 dB over a prolonged period.
• WHO recommended that the sound level indoors should be less than 30 dB.

Properties of sound

1. Loudness

• It is the intensity and strength of sound perceived by human ears.
• It is measured in decibels.
• The intensity of the audible sound is 10 decibels.

2. Frequency

• It is measured in Hertz.
• It is defined as the number of vibrations per second.
• The range of human hearing is 20-20,000Hz.
• Above 20,000 Hz is called ultrasound, and below 20Hz is called infra-sound.

Effects of Noise Pollution

• Hypertension: Exposure to loud and unpleasant noise elevates blood levels which can cause hypertension in humans.
• Annoyance: Irregular and loud sounds cause displeasure to hear and annoy.
• Physiological effects: The physiological features like breathing amplitude, blood pressure, heart-beat rate, pulse rate, and blood cholesterol are affected.
• Hearing disability: Constant exposure to loud sound cause damage to eardrums leading to loss of hearing.
• Sleeping disorder: Excessive and loud noise affect the sleep cycle, leading to low-energy level and fatigue.
• Human performance: The working performance of workers/humans will be affected as it distracts the concentration.
• Nervous system: It causes pain, ringing in the ears, and feeling of tiredness, thereby affecting the functioning of the human system.
• Damage to the material: The buildings and materials may get damaged by exposure to infrasonic/ultrasonic waves and even collapse.

Control

• Noise level reduction from domestic sectors.
• Regular maintenance of automobiles leads to the lowering of sound.
• Loud Speakers should be prohibited.
• Heavy machinery used in Industries should be regularly maintained.
• The building should be designed in such a way that it absorbs sound.
• The planting of trees leads to a reduction in Noise Pollution.
• Highways traffic should be diverted from cities and towns to bypasses and over-bridges.
• Workers working in Heavy industries should be provided with protective devices like cotton plugs.

Government Measures

• Ambient noise level for various areas has been defined by Noise Pollution (Control and Regulation) Rules, 2000.

• Monitoring noise Pollution in seven metropolitan cities- Mumbai, Delhi, Kolkata, Chennai, Bangalore, Lucknow, and Hyderabad through a network of 70 noise-monitoring stations.
• Excessive noise is a crime under section 268 of IPC.
• Environment Protection Act, 1986 has recognized noise as a pollutant.
• 'Silence Zone'- 100-meter radius around schools, colleges, hospitals, and courts.
• Section 133 of IPC uses loudspeakers in public as a punishable offense.
• Central Motor vehicle Rule, 1989 banned pressure horns (sirens and multi-tone horns) except for police vans, fire brigade, and ambulances.

Question for Practice

1. Acceptable "Noise Pollution Level" In India range between:

A. 16-35 dB

B. 40-75 dB

C. 70-100 dB

D. 10-15 dB

Answer in the comment section.