Sound Levels
In the case of sound levels, engine operation is of greatest impact with respect to mobile sources such as automobiles and trucks. Engine noise is a particularly large component of mobile source noise for vehicles operating at lower speeds, where aerodynamic and tire noise is less significant. Petrol and diesel engines are fitted with mufflers (silencers) to reduce noise.
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Famous quotes containing the words sound and/or levels:
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—E.M. (Edward Morgan)
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