Diagrammatic guide signs for use on controlled access highways. Volume 1, Recommendations for diagrammatic guide signs

1972Final reportMast, T. M.PDFTech ReportFHWA-RD-73-21;NTIS-PB226077DOT-FH-11-7815/StaffGuide signsSymbol signsWarrants (Traffic control devices)StandardsFreewaysTraffic signs and signals - United StatesTraffic safety - United StatesUnited StatesUnited States. Federal Highway Administration. Offices of Research and DevelopmentMast, Truman M.Kolsrud, Gretchen S.United States. Federal Highway Administration. Traffic Systems DivisionBiotechnology, inc.NTL-OPERATIONS AND TRAFFIC CONTROLS-Traffic Control DevicesNTL-SAFETY AND SECURITY-Highway SafetyFederal Highway AdministrationThe purpose of the diagrammatic signing research project was to develop warrants and standards for the use of diagrammatic guide signs on controlled access highways. Volume 1 summarizes the entire diagrammatic signing research program objectives sponsored by the Federal Highway Administration. It presents the recommended warrants, standards and guidelines for diagrammatic guide signs and the research basis for the recommendations, and suggests techniques and measures for the evaluation of highway signing. This volume was prepared jointly by the Office of Research, Federal Highway Administration, and BioTechnology, Inc. Research findings obtained under the project indicate that drivers require more time to read and interpret information on diagrammatic signs in comparison with conventional signs. Moreover, as the graphic component on the sign becomes more complex, driver information interpretation time increases. Accordingly, in those cases where diagrammatic signs have been recommended, the standards specify that simple graphic designs must be used. Research results clearly indicate that diagrammatic guide signs will produce a benefit to motorist performance at interchanges where traffic must exit to the left of the through route. Such interchanges include major forks where exiting traffic must take the left fork. Also included are interchanges where there is a single left exit from the roadway and where there is a left exit in combination with a right exit