AN INVESTIGATION OF HEADLIGHT GLARE AS RELATED TO LATERAL SEPARATION OF VEHICLES

THE CURRENT STATUS OF KNOWLEDGE ON HEADLIGHT GLARE IS DESCRIBED. THE FACTORS INFLUENCING THE AMOUNT AND EFFECTS OF GLARE, THE SUGGESTED METHODS OF ALLEVIATING GLARE, AND THE SOURCES OF EXPERIMENTAL ERROR ARE INCLUDED. ACTUAL FIELD TESTING WAS CONDUCTED IN TWO PHASES: (1) DISABILITY GLARE, WHICH AFFECTS SEEING DISTANCE AND (2) DISCOMFORT GLARE, WHICH IS A PSYCHOLOGICAL PHENOMENON. THE DISABILITY GLARE TESTS INVOLVED OBTAINING SEEING DISTANCES FOR TEN SUBJECTS, EIGHT TARGETS, TWO BEAM CONFIGURATIONS, AND FOUR LATERAL SEPARATIONS (6, 33, 72, 94 FT). DATA WERE ALSO COLLECTED FOR POLARIZES HEADLIGHTING AT THE 6-FT LATERAL SEPARATION. CONCLUSIONS AS TO THE OPTIMUM LATERAL SEPARATION FOR PROVIDING SEEING DISTANCES EQUAL TO OR IN EXCESS OF THE SAFE STOPPING SIGHT DISTANCE FOR 70 MPH ARE MADE, AS WELL AS STATEMENTS SHOWING THE ADVANTAGES OF POLARIZED HEADLIGHTING FOR THE 6-FT LATERAL SEPARATION. STATIC AND DYNAMIC TESTS WERE CONDUCTED ON DISCOMFORT GLARE. THE STATIC TESTS BORDERLINE BETWEEN COMFORT AND DISCOMFORT (BCD) VALUES FOR TEN SUBJECTS, EIGHT LONGITUDINAL DISTANCES, TWO BEAM CONFIGURATION AND FOUR LATERAL SEPARATIONS (6, 33, 60, 94 FT). CONCLUSIONS WERE DRAWN REGARDING THE LATERAL SEPARATION NEEDED TO REDUCE THE DISCOMFORT OF ONCOMING HEADLIGHT GLARE AND THE LATERAL SEPARATION WHICH PRODUCED TOLERABLE LEVELS OF DISABILITY AND DISCOMFORT GLARE. DISCUSSIONS WHICH EVALUATE THE RESEARCH AND SUGGEST THE DIRECTION OF FUTURE STUDY ARE INCLUDED. /AUTHOR/

• Supplemental Notes:
  • No 496, 108 PP, 12 FIG, 11 TAB, 291 REF
• Authors:
  • Webster, L A
  • Yeatman, F R
• Publication Date: 1968

Media Info

• Serial:
  • Illinois Univ Eng Exp Sta Bulletin

Subject/Index Terms

• TRT Terms: Beams; Dynamic tests; Errors; Field tests; Glare; Headlamps; Lateral placement; Methodology; Psychological aspects; Shape; Sight distance; Static tests; Variables
• Uncontrolled Terms: Configuration; Data; Lateral; Separation; Sources
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00223171
• Record Type: Publication
• Source Agency: Nat Safety Council Safety Res Info Serv
• Files: TRIS
• Created Date: Nov 23 1970 12:00AM