Environmental Pollution by Traffic Noise in the City of Colombo, Sri Lanka
Traffic noise levels in most cities of the world are higher than the recommended levels. Exposure to high levels of noise may cause adverse health effects such as ischemic heart diseases and noise induced hearing loss. We conducted a cross-sectional study to determine road traffic noise levels at 60 selected locations in the city of Colombo, Sri Lanka. On randomly selected days we measured equivalent continuous sound pressure level (LAeq) for six hours during the day. From these measurements LAeq for eight hours were calculated and used as the average noise level of a particular location. LAeq (8 hrs) within Colombo ranged 76.6 to 84.0 dB; well above the Sri Lankan recommendation of 63.0 dB (an increase of 13.3 to 21.0 dB), and the WHO recommendation of 55.0 dB (an increase of 21.6 to 29.0 dB). These levels translate into increase of sound pressure level by 21.4 to 794.3 times above the recommendations on the logarithmic scale of dB. Thirty-eight of 60 locations recorded levels more than 80.0 dB. Road traffic noise levels in Colombo were well above the recommended levels. Though the increase in measured decibels might not appear to be too high, in reality this translates into an increase manifold times in the sound pressure level that reaches the ear.
Berglund, B. and T. Lindvall (1995). Community Noise. Archives of the Center for Sensory Research, Stockhalm.
Berglund, B., Lindvall, T. and D.H. Schwela (1999). Guidelines for community noise. World Health Organization, Geneva.
Department of Census and Statistics (2012). Census of population and housing 2011. Population of Sri Lanka by Districts. [Accessed 04 April 2013] http://www. statistics.gov.lk/PopHouSat/CPH2011/Pages/sm/CPH%20 2011_R1.pdf
Gaja, E., Gimenez, A., Sancho, S. and A. Reig (2002). Sampling techniques for the estimation of the annual equivalent noise level under urban traffic conditions. Applied Acoustics, Elsevier, 64(1): 43-53.
Kalansuriya, C.M. (2010). Community perception and assessment of transportation noise. MPhil. Faculty of Science, University of Colombo, Sri Lanka.
Li, B., Tao, S. and R.W. Dawson (2002). Evaluation and analysis of traffic noise from the main urban roads in Beijing. Applied Acoustics, Elsevier, 63(10): 1137-1142.
Ministry of Transport, Environment and Women’s Affairs (1996). National Environmental (noise control) Regulations No. 1, 1996. Colombo, Sri Lanka.
Onnu, M.U. (2000). Road traffic noise in Nigeria: Measurements, analysis and evaluation of nuisance. Journal of Sound and Vibration, Elsevier, 233(3): 391-405.
Ozer, S., Yilmaz, H., Yesil, M. and P. Yesil (2009). Evaluation of noise pollution caused by vehicles in the city of Tokat, Turkey. Scientific Research and Essay, Academin Journals, Nigeria, 4(11): 1205-1212.
Piccolo, A., Plutino, D. and G. Cannistraro (2005). Evolution and analysis of the environmental noise of Messina, Italy. Applied Acoustics, Elsevier, 66(4): 447-465.
Sampath, S., Murali Das, S. and V. Sasi Kumar (2004). Ambient noise levels in major cities in Kerala. The Journal of Indian Geophysical Union, National Geophysical Research Institute, Hydrabad, India, 8(4): 293-298.
Simpson, M. and R. Bruce (1981). Noise in America: The extent of noise problem. EPA Report No. 550/9-81-101.
[Accessed 09 November 2012] http://www.nonoise.org/ epa/Roll6/roll6doc7.pdf
Walls, C. (1994). Noise induced hearing loss of occupational origin: A guide for medical practitioners. Occupational Safety and Health Service, Department of Labour, Wellington, New Zealand.