This paper discusses the ability of drivers to perceive traffic flow quality on the basis of A,B,C,D,F, grading scale signs along major freeways, when F is total congestion and A is the smoothest, fastest flow possible. In Hennepin County, Minnesota, driver perception was evaluated by using questionnaires. It was found that 52 percent of the respondents correctly identified the correct definition. Also it was found that peak-hour users were more sure and more accurate in their responses, and those who had heard or read about the grade signs were more able to correctly define the meanings. Overall, the survey findings demonstrate that a significant majority of drivers can correctly interpret the meanings of the traffic-condition grades A,B,C,D,F. This ability could be improved by more effective media publicity. The survey also demonstrates that many drivers use the information communicated by the grade in their subsequent route-choice process and travel. Therefore, it can be concluded that the criteria of understanding and use are met and that the traffic grade concept is valid.

Media Info

  • Media Type: Print
  • Features: Figures; Photos;
  • Pagination: pp 105-108
  • Monograph Title: Urban system operation and freeways
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00196608
  • Record Type: Publication
  • ISBN: 0309028272
  • Files: TRIS, TRB
  • Created Date: Sep 15 1979 12:00AM