ROAD traffic noise has risen compared to about 10 years ago.
Universiti Teknologi Malaysia’s (UTM) Institute of Noise and Vibration director Prof Dr Mohd Salman Leong says this is based on measurements taken by the institute in several locations in Malaysia.
For example, the average noise levels at daytime along the Cheras-Kajang Expressway in the Klang Valley spiked by 19% or 12.4dBA (dBA stands for “A-weighted decibels”, and is a measure of sound).
From 64dBA in 2010, the levels increased to 76.4dBA in 2017 – one can imagine the difference in volume to sound like the noise going from a business office sound level to the level of a vacuum cleaner in action.
At night, the expressway became noisier too – from 57.8dBA in 2010 to 73.2dBA in 2017.
“The noise increase is most probably due to increased traffic volume and vehicles travelling at higher speeds, ” Dr Salman says, adding that some toll booths along the highway were abolished in 2012, hence increasing the chances of speeding.
The percentage of heavy vehicles on the road may also have increased, leading to louder traffic, he says.
In another area, noise measurements at a road in the Kuala Lumpur suburb of Taman Tun Dr Ismail, Pinggir Zaaba facing the LDP Highway, also showed increases.
During the day, noise levels rose from 65.7dBA in 2010 to 70.6dBA, while at night, the levels increased from 64.7dBA to 67.4dBA.
Dr Salman points out that road traffic is recognised as the most pervasive and widespread noise source that affects communities.
“Other noise pollution sources tend to be more localised.
“This is true in Malaysia, and is similar to other cities in the world based on noise studies done in Malaysia and elsewhere.
“This is a direct consequence of physical development, ” he explains.
The top three causes of noise pollution in Malaysia today based on UTM’s observations and previous studies are road traffic, construction works and commercial activities, including entertainment premises.
Noise pollution in general has increased with increasing development in Malaysia in a similar manner as in other countries.
“There are, however, concerted efforts in the European Union and other developed countries to mitigate further increases and reduce noise through policy planning and noise abatement measures.
“The same can be said about this in Malaysia, especially in new infrastructure projects like highways and railways, as well as construction works, ” he adds.
To the average person, Dr Salman says noise pollution can be defined as unwanted or excessive sound that affects communities.
“Acceptable environmental noise is dependent on land use and the community where the noise is generated.
“In an urban residential area, the internationally acceptable noise levels are 65dBA (the volume of laughter) during the daytime and 60dBA (the volume of normal conversation) at night, ” he says.
“Noise levels need to be substantially higher than this to be unhealthy, ” Dr Salman says.
The World Health Organisation Guideline for Community Noise and the US Environmental Protection Agency recommend an outdoor ambient noise limit of 75dBA for safe, long-term environmental noise exposure.
“In the workplace occupational health risk for hearing impairment, 85dBA is the recommended noise limit (for an eight-hour working day) for long term exposure for 40 (working) years.
“It is generally safe for a person to be exposed to a noise level higher than the mentioned levels, as safe exposure is dependent on the sound level and duration of exposure, ” Dr Salman says.
Environmental noise pollution is not as unhealthy or damaging as excessive noise in the workplace.
“Noise pollution is generally a disturbance issue.
“It does, however, affect quality of life, can disturb sleep and, for some people, lead to increased stress, ” he says.
But the main effects from noise is usually annoyance.
Higher noise levels would have a higher percentage of the population perceiving the noise to be highly annoying, according to the Department of Environment’s Guidelines on Environmental Limits and Control 2019.