Environmental Studies Unit 9 – Noise Pollution

Vocabulary flashcards cover key terms, sources, effects, and control measures related to Unit 9 – Noise Pollution, aiding students in mastering essential definitions for exam preparation.

Noise Pollution

Any undesired, unpleasant, or high-level sound that disturbs human, animal, or environmental health.

Noise

An unwanted and nasty sound (Latin: ‘Nausea’) that causes discomfort to living organisms.

Decibel (dB)

The standard SI unit for measuring sound intensity; 1 dB is the faintest sound the human ear can detect.

Sound Pressure Level

A measure of how humans perceive sound intensity; varies among individuals.

Noise Exposure Limits

Acceptable noise thresholds for humans, as recommended by the World Health Organization.

Sound Level Meter

Instrument used to measure and monitor environmental sound levels.

Industrialisation (Noise Source)

Use of heavy machinery—compressors, generators, metal presses—producing excessive noise in factories and plants.

Poor Urban Planning

Congested housing, insufficient parking, and small industries that collectively raise city noise levels.

Social Events

Parties, weddings, and festivals that play loud music via loudspeakers, creating community noise.

Transportation Noise

Horns, engines, and traffic from cars, buses, trains, and aircraft contributing to urban noise pollution.

Construction Activities

Equipment such as bulldozers, air hammers, and dump trucks that generate high-intensity site noise.

Household Chores (Noise Source)

Domestic gadgets—vacuum cleaners, mixer-grinders, TV, mobile phones—that raise indoor noise levels.

Fireworks

Explosive celebrations (e.g., Diwali crackers) producing hazardous sound bursts and potential hearing loss.

Agricultural Machines

Tractors, harvesters, thrashers, and powered tillers whose operation creates rural noise pollution.

Defence Equipment

Military drills, artillery, jet engines, and rocket launches emitting extreme noise levels.

Miscellaneous Causes

Noise from boilers, plumbing, generators, markets, schools, bus stands, and office hardware.

NIHL (Noise-Induced Hearing Loss)

Permanent or temporary hearing damage caused by prolonged exposure to loud sounds.

High Blood Pressure (Noise Effect)

Elevated heart rate and hypertension triggered by continuous loud noise exposure.

Loss of Hearing Ability

Damage to inner-ear cells and eardrums from noise levels beyond acceptable limits.

Disturbance (Mental)

Sleep disruption, stress, anxiety, and reduced concentration resulting from persistent noise.

Effect on Crops

Reduced growth quality because plants require quiet environments; chronic noise hinders development.

Effect on Buildings

Vibrations from heavy noise causing cracks, shattered glass, and structural damage.

Effect on Marine Animals

Underwater noise (ships, dynamite fishing) disrupting navigation and survival of sea life.

Green Muffler

Planting dense rows of trees/bushes as barriers to absorb and dampen sound waves.

Soundproofing

Using insulated windows, doors, and materials to block external noise intrusion.

Barriers (Trees)

Natural or artificial structures placed between source and receiver to reduce noise transmission.

Lubrication & Maintenance

Regular servicing of machines to lessen friction and lower noise emissions.

Earplugs

Personal protective devices worn in ears to reduce incoming sound and protect hearing.

Control at Receiver's End

Providing ear muffs, noise caps, or plugs to individuals in noisy workplaces.

Controlling at Source

Reducing noise by redesigning, enclosing, or damping vibrating machinery at its origin.

Innovative Designing

Architectural planning—well-sealed doors/windows—to minimize indoor penetration of outdoor noise.

Noise Mufflers

Silencing devices fitted to engines or exhausts to lower emitted sound levels.

Soundproof Windows

Double-pane or insulated glass installations that block external noise.

Acceptable Noise Level

General comfort range of 30 dB – 60 dB for humans; levels beyond can be harmful.

Vibration Damping

Placing materials such as neoprene or cork under machines to absorb vibratory noise.

WHO Noise Guidelines

International recommendations specifying safe exposure levels to prevent health impacts.

Hearing Protection Aids

Collective term for earplugs, earmuffs, and noise caps used to safeguard auditory health.