noise barrier

acoustics

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July 1, 2026

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The term "noise barrier" refers to structures erected to reduce sound levels, often placed alongside highways to shield residential areas from traffic noise. These barriers work by limiting the diffraction of sound waves, particularly lower frequencies common in road noise. For maximum effectiveness, noise barriers should be positioned as close as possible to either the noise source or the observer, ideally the source. They also need to minimize sound transmission to achieve significant noise reduction.1

It is important to note that the term "sound barrier" can also refer to a phenomenon in aerodynamics, where an aircraft experiences a sudden large increase in drag as it approaches the speed of sound. This is distinct from the acoustic concept of a noise barrier.2

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Noise regulation and mitigation
…noise is the erection of noise barriers alongside the highway, separating the highway from adjacent residential areas. The effectiveness of such barriers is limited by the diffraction of sound, which is greater at the lower frequencies that often predominate in road noise, especially from large vehicles. In order to be…
Read More
…noise is the erection of noise barriers alongside the highway, separating the highway from adjacent residential areas. The effectiveness of such barriers is limited by the diffraction of sound, which is greater at the lower frequencies that often predominate in road noise, especially from large vehicles. In order to be…
Read More