Highway Capacity Manual, 3rd Edition

TRB Special Report 209: Highway Capacity Manual, 3rd Edition is a collection of state-of-the-art techniques for estimating capacity and determining level of service for many transportation facilities and modes. The 3rd edition of this manual was updated in 2000 as Highway Capacity Manual 2000.

The first Highway Capacity Manual was published in 1950 and provided definitions of key terms, a compilation of maximum observed flows, and the initial fundamentals of capacity. Analytical procedures were included for uninterrupted-flow facilities, signalized intersections, weaving sections, and ramps. The second edition was published in 1965. It was a significant extension of the 1950 edition and is most noted for its introduction of the level-of-service concept. The third edition was published in 1985. Again the breadth and depth of the previous manuals were extended. The 1985 edition is perhaps most noted for the extension into facilities other than highways, refinements to the level-of-service concept, and the accompanying computer software. The 1994 update of the third edition provided new analytical procedures in response to the increased levels of research and professional interest in this topic.