The objectives of this study were to determine average accident rates tor various categories of at-grade intersections and to identify intersections having high accident rates. This involved locating intersections at two or more state-maintained highways and determining the appropriate volumes to use as well as locating the accidents occurring at any given intersection.

A procedure was developed to allow tor the identification of intersections having high or critical accident rates. A list at the intersections of two or more state-maintained roadways was developed. A total of 6,707 intersections were included in the file. Using county, route and milepoint information, accident and volume data were associated with each intersection. Accident rates were calculated for each intersection. The rates are in terms of accidents per million entering vehicles (ACC/MV). Statewide average and critical accident rates were calculated by functional classification. Intersections having critical accident rates were then identified using both the typical procedure and a procedure which accounted for the regression-to-the-mean bias.

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The contents of this report reflect the views of the author, who is responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation.