Overtaking and passing maneuvers are two of the most common sources of conflict between two or more vehicles on two-lane, two-way rural roads. While the signing and marking of passing/no-passing zones has received considerable attention there is still a lack of consensus relative to the effectiveness of the various methods, how they should be used, and what the enforcement policies should be. In this context, the research effort reported on herein was directed to the evaluation of several alternative methods for marking/signing of passing and no-passing zones in rural two-lane situations.

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