The objective of this project is to develop accident reduction factors associated with various types of highway safety improvements. These factors will be used in the cost-optimization procedure to rank safety improvements.

The basis of the accident reduction factors developed in this study is a survey of states and a review of literature. The recommended reduction factors are presented in a table which lists the percent reduction in all accidents or specific types of accidents for given types of improvements.

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The contents of this report reflect the views of the authors, who are 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 or the Kentucky Transportation Cabinet. This report does not constitute a standard, specification, or regulation.