Individual noise measurements were obtained on 10,500 motor vehicles operating on Kentucky highways. The roadways were selected to represent varied geometric and environmental conditions and posted speed limits. Percentages of automobiles and trucks exceeding a given level of noise were determined. As expected, noise levels of trucks were significantly higher than for automobiles, and larger trucks produced higher noise levels than smaller trucks. For any vehicle type, noise increased with an increase in speed limit.

Report Date


Report Number

No. 375

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The contents of this report reflect the views of the authors who are responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Bureau of Highways. This report does not constitute a standard, specification, or regulation.