The Highway Capacity Manual (HCM) is a publication of the

Transportation Research Board The Transportation Research Board (TRB) is a division of the National Academy of Sciences, Engineering, and Medicine, formerly the National Research Council of the United States, which serves as an independent adviser to the President of the Unite ...

(TRB) of the

National Academies of Sciences, Engineering, and Medicine The National Academies of Sciences, Engineering, and Medicine (also known as NASEM or the National Academies) are the collective scientific national academy of the United States. The name is used interchangeably in two senses: (1) as an umbrell ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. It contains concepts, guidelines, and computational procedures for

computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, e ...

the capacity and quality of service of various highway facilities, including

freeway A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms ...

s, highways, arterial roads,

roundabout A roundabout is a type of circular intersection or junction in which road traffic is permitted to flow in one direction around a central island, and priority is typically given to traffic already in the junction.''The New Shorter Oxford En ...

s, signalized and unsignalized intersections,

interchanges Interchange may refer to: Transport * Interchange (road), a collection of ramps, exits, and entrances between two or more highways * Interchange (freight rail), the transfer of freight cars between railroad companies * Interchange station, a rai ...

, rural highways, and the effects of

mass transit Public transport (also known as public transportation, public transit, mass transit, or simply transit) is a system of transport for passengers by group travel systems available for use by the general public unlike private transport, typical ...

pedestrian A pedestrian is a person traveling on foot, whether walking or running. In modern times, the term usually refers to someone walking on a road or pavement, but this was not the case historically. The meaning of pedestrian is displayed with ...

s, and

bicycle A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bic ...

s on the performance of these systems. There have been seven editions with improved and updated procedures from 1950 to 2022, and major updates to the HCM 1985 edition, in 1994, 1997 and 2015. Chapter 1 The HCM has been a worldwide reference for transportation and traffic engineering scholars and practitioners, and also the base of several country-specific capacity manuals. The most-recent version, the ''Highway Capacity Manual, Seventh Edition: A Guide for Multimodal Mobility Analysis'' was released in January 2022. Before that HCM 2016 or HCM6, was released in October 2016. The latest edition incorporates the latest research on highway capacity, quality of service, active traffic and

demand management Demand management is a planning methodology used to forecast, plan for and manage the demand for products and services. This can be at macro-levels as in economics and at micro-levels within individual organizations. For example, at macro-leve ...

, and travel time reliability. The Sixth Edition of HCM consists of four Volumes. Three volumes are available either in hard copy or PDF, whereas Volume IV is only available online. Volume IV of HCM is free, only requiring readers to create an account i
hcmvolume4.org

History

There are more than seven decades of research behind the ''HCM''. The first edition of the ''Highway Capacity Manual'' was released in 1950 and contained 147 pages broken apart into eight parts. It was the result of a collaborative effort between the Transportation Research Board (TRB) and the Bureau of Public Roads, the predecessor to the Federal Highway Administration. The following editions were published by TRB in 1965, 1985, 2000, 2010, 2016, and 2022. The fifth edition of ''HCM 2010'' was the culmination of a multiagency effort—including TRB, American Association of State Highway and Transportation Officials (AASHTO), and Federal Highway Administration—over many years to meet the changing analytical needs and to provide contemporary evaluation tools. In 2013 TRB contracted the development of a major update to the 2010 Highway Capacity Manual. The new and revised material was scheduled to be published as a 2015 interim update of the HCM 2010, known as the ''HCM 2015 Update''. The final version, published as the ''Highway Capacity Manual, Sixth Edition: A Guide for Multimodal Mobility Analysis'', or HCM 2016, or HCM6, was released in October 2016 and is available from TRB. The sixth edition incorporates the latest research on highway capacity, quality of service, active traffic and

, and travel time reliability.

References

{{reflist

External links

Official website HCM 6th EditionHCM6 Overview
McTrans, Transportation Institute, University of Florida
Highway Capacity Manual, 6th Edition (2016), Volume 4
Road traffic management Roads in the United States

History

See also

References

External links