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The megacities of Pakistan, such as Karachi, Lahore, Islamabad and Rawalpindi, face the issue of noise pollution. The main source of this pollution is the traffic noise caused by buses, cars, trucks, rickshaws and water tankers. A study showed that on one of Karachi's main roads, the average noise level was around 90 dB and was capable of ...
Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.
Example of transportation noise and how it affects the community. Environmental noise is an accumulation of noise pollution that occurs outside. This noise can be caused by transport, industrial, and recreational activities. [1] Noise is frequently described as 'unwanted sound'. Within this context, environmental noise is generally present in ...
Noise pollution which encompasses roadway noise, aircraft noise, industrial noise as well as high-intensity sonar. The noise for Karachi came to 80 dB (A), the General Noise Index x (G.N.I.) to 460, and the noise pollution level (N.P.L.) to 99 dB (A). These values are significantly higher (P less than 0.01) than the available international data.
A noise barrier (also called a soundwall, noise wall, sound berm, sound barrier, or acoustical barrier) is an exterior structure designed to protect inhabitants of sensitive land use areas from noise pollution. Noise barriers are the most effective method of mitigating roadway, railway, and industrial noise sources – other than cessation of ...
Noise control is a set of strategies to reduce noise pollution by reducing noise at its source, by inhibiting sound propagation using noise barriers or similar, or by the use of ear protection (earmuffs or earplugs). [20] Control at the source is the most cost-effective way of providing noise control.
Noise measurement can also be part of a test procedure using white noise, or some other specialized form of test signal.In audio systems and broadcasting, specific methods are used to obtain subjectively valid results in order that different devices and signal paths may be compared regardless of the inconsistent spectral distribution and temporal properties of the noise that they generate.
Electric and hybrid vehicles could reduce noise pollution, but only if those vehicles make up a high proportion of total vehicles on the road; even if traffic in an urban area reached a makeup of fifty percent electric vehicles, the overall noise reduction achieved would only be a few decibels and would be barely noticeable. [12]