Highway Capacity Manual

The Highway Capacity Manual (HCM) contains concepts, guidelines, and computational procedures for computing the capacity and quality of service of various highway facilities, including freeways, signalized and unsignalized intersections, rural highways, and the effects of transit, pedestrians, and bicycles on the performance of these systems.

The New HCM Sixth Edition

A major update to the Highway Capacity Manual has been published during the third quarter of 2016. The new manual is entitled, Highway Capacity Manual (HCM) 6th Edition:  A Guide for Multimodal Mobility Analysis. In addition to the added subtitle, which places an emphasis on “multimodal,” the HCM is called 6th Edition (rather than having a year attached to it), with a version number provided for each chapter, to allow for more frequent updates of individual chapters or smaller portions of the manual as new research becomes available. New tools provided in this edition estimate travel time reliability measures, evaluate Active Traffic and Demand Management (ATDM) impacts, assess alternative intersection and interchange designs, and provide multimodal LOS estimates, among others. The 6th edition of HCM is accessible via this link: http://www.trb.org/publications/hcm6e.aspx