A STUDY OF SELECTION OF YELLOW CLEARANCE INTERVALS FOR TRAFFIC SIGNALS

THERE IS GREAT VARIANCE IN THE VALUE USED BY DIFFERENT STATES AND DIFFERENT REFERENCES IN SELECTION OF SIGNAL YELLOW INTERVAL LENGTH. BY A THEORETICAL AND LOGICAL ANALYTICAL APPROACH, INCLUDING CONSIDERATION OF SOME HUMAN BEHAVIOR ITEMS, THIS INVESTIGATION SOUGHT TO ARRIVE AT A REASONABLE COMPROMISE OF QUANTITATIVE VALUES, PARTICULARLY REGARDING PERCEPTION-REACTION TIME, FOR USE IN CALCULATING LENGTH OF YELLOW FOR STOP AND GO SIGNALS. THE DATA TAKEN BY THE LAPSED TIME MOTION PICTURE TECHNIQUE SUPPORTS THE CONCLUSION, BASED ON THE 85TH PERCENTILE FIGURE, THAT THE AASHO RECOMMENDATION OF ONE AND ONE-HALF SECONDS PERCEPTION- REACTION TIME WHEN A STOP CHOICE IS MADE IS VERY REASONABLE. THIS WOULD LEAD TO A THEORETICAL NEED FOR INCREASE OF YELLOW INTERVALS. HOWEVER, OTHER LOGIC DOES NOT SUPPORT THIS MAJOR INCREASE OVER THE ONE SECOND RECOMMENDED BY THE I.T.E. HANDBOOK AND OTHER STATES' PRACTICES, SO THE PRESENT POLICY USED BY MICHIGAN SEEMS A REASONABLE AND JUSTIFIABLE COMPROMISE. EXTENSIVE ADDED RESEARCH IS NEEDED ESPECIALLY IN THE FIELD OF DRIVER BEHAVIOR AND CAPABILITIES WITH REGARD TO USE OF THE YELLOW INTERVAL BEFORE THE OPTIMUM COMPROMISE CAN BE REACHED. /AUTHOR/

• Supplemental Notes:
  • Rept Tsd-tr-104-69, 66 PP, 20 FIG
• Corporate Authors:

  Michigan Department of State Highways

  State Highways Building, PO Drawer K
  Lansing, MI  United States  48904
• Authors:
  • Jenkins, R S
• Publication Date: 1969-2

Subject/Index Terms

• TRT Terms: Behavior; Drivers; Motion pictures; Reaction time; Theory; Time intervals; Traffic signals; Yellow interval (Traffic signal cycle)
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00225663
• Record Type: Publication
• Files: TRIS, STATEDOT
• Created Date: Mar 19 1971 12:00AM