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Noise Pollution. Also called “environmental noise”. D ispleasing sound that disrupts the activity or balance of life. ( The word noise comes from the Latin word nausea, meaning seasickness .)
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Also called “environmental noise” • Displeasing sound that disrupts the activity or balance of life.(The word noise comes from the Latin word nausea, meaning seasickness.) • Sources – construction, transportation, motor vehicles, aircraft, railway noise, industrial machinery, car alarms, audio systems, barking dogs (!) …..
Measured in • decibels (db) – a measure of pressure • Noise above 140 db can cause pain • Constant noise above 85 db can cause hearing loss Sound waves (vibration of air molecules) put pressure on the eardrum – vibration is converted into nerve signals sent to the brain
Effects on humans • Behavioural – stress, annoyance, aggression • Health – sleep disturbance, tinnitus (ringing in ears), hearing loss, rise in blood pressure, heart disease, immune system changes, low birthweight babies… • Volume AND Length of exposure will determine effects.
Mitigation (lowering) • Barriers on highways • Quieter jet engines
Limitation of trucks on some roads • Ear protection (e.g. industrial workers) • Noise codes (e.g. limit noise after 11 pm), specific equipment regulations