NOISE pollution is a silent killer. The source of most outdoor noise worldwide is mainly caused by machines and transportation systems, motor vehicles engines, aircrafts and trains. Outdoor noise is summarised by the word environmental noise.Â
Poor urban planning may give rise to noise pollution, since construction of industrial and residential buildings can result in noise pollution. Documented problems associated with urban noise go back as far as Ancient Rome.Â
High noise levels can lead to hearing loss and can contribute to cardiovascular effects in humans and an increased incidence of coronary artery disease.Â
In animals, noise can increase the risk of death by altering predator or prey detection, and interfere with reproduction and navigation, and contribute to permanent hearing loss.Â
Sound strength is measured in decibel (dB). About 85 dB can damage our hearing. According to World Health Organisation (WHO), generally 60 dB noise can damage a person's hearing ability temporarily and 100 dB may cause him/her complete deafness.Â
The noise in Dhaka city's busy roads has been estimated to somewhere near 60dB which is much above the tolerable level.Â
We see in traffic signal points horns being blown unnecessarily. I have seen some bus drivers blowing their horns as they drive speedily. Â Sound pollution is especially harmful for children and elderly people.Â
Older males exposed to significant occupational noise demonstrate more significantly reduced hearing sensitivity than their non-exposed peers, though differences in hearing sensitivity decrease with time. We see today's young people listening to loud music from iPod which is also dangerous. Â
Street noise can be reduced by the use of noise barriers, limitation of vehicle speeds, alteration of roadway surface texture, limitation of heavy vehicles, use of traffic controls. Â
Aircraft noise can be reduced by using quieter jet engines. Altering flight paths and runways has benefited residents near airports.
We must create a sound pollution free environment for ourselves and for our children. We should not forget the health quote "A healthy attitude is contagious but don't wait to catch it from others. Be a carrier."
Rumana Sharmeen
Dhaka University Â