This area is intended for interaction among HCM users to exchange information and ideas on applying HCM procedures. When issues rise to the level that requires formal response from the TRB Committee on Highway Capacity and Quality of Service, they should be submitted for Interpretation Request.
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RE: Unable to download Supplemental 28
by Ian Johnson
General questions, applications, and questions regarding the HCM 6th Edition
RE: QAP diagrams for leading Protected-Permitted
by Shen Dong
Questions & Clarifications
Having trouble with something in the HCM 6th Edition? Need further information to clarify a position? Conversations here will help create the ongoing errata for the manual found in the Interpretations page on this website.
RE: Climbing lane on a freeway section LoS procedure?
by Scott Washburn