Incorporating Highway Safety into Level of Service

by Walter J. Diewald, (A.M.ASCE), Transp. Systems Planner; Transp. and Space Systems Dept., Battelle Columbus Labs., Columbus, OH,

Serial Information: Transportation Engineering Journal of ASCE, 1974, Vol. 100, Issue 2, Pg. 417-429

Document Type: Journal Paper


The Highway Capacity Manual is used extensively for highway design and highway evaluation purposes; it relies upon the relationship between travel speed and the volume/capacity ratio for an expression of the level or quality of traffic service. A need exists to include more consideration of highway safety within the concept of level of service, and an examination of the concept of probability of danger of collision has been conducted. This approach takes into account various values of the probability of danger of collision and provides a means of introducing a third major parameter into level of service determination. The results indicate that, for the single-lane, car-following situation, the current levels of service are not completely adequate for safety considerations.

Subject Headings: Highway and road design | Highways and roads | Safety | Traffic capacity | Probability | Traffic accidents | Traffic volume | Traffic speed

Services: Buy this book/Buy this article


Return to search