A STUDY OF DAYTIME RUNNING LIGHT DESIGN FACTORS. FINAL REPORT

Prior research has suggested that use of daytime running lights (DRL) on operating vehicles can reduce the frequency and severity of collisions. Possible DRL implementations include high-beam headlamps (with reduced intensity), low-beam headlamps, turn signals, parking lamps and dedicated DRL lamps. Questions have, therefore, arisen regarding the impact on DRL effectiveness of a number of lamp design features and parameters. Research issues involve the effects on vehicle conspicuity under daytime illumination but also potential negative consequences of DRL such as masking of adjacent turn signals and glare under dawn/dusk conditions. The objective of the effort reported here was to obtain data on perceptual effects of DRL intensity, lamp area, color, number of lamps and lamp/background contrast in the above areas. Three experiments were performed to investigate human performance as functions of these design parameters in tasks involving peripheral vehicle detection, turn signal detection and rearview mirror discomfort glare produced by DRL. Detection distance for a vehicle approaching at a 15 degree peripheral angle was influenced primarily by DRL intensity in the range from 0 to 2000 cd. and was greater for dual separated lamps than for a single center-mounted one. Amber lamps resulted in greater detection distances than did clear ones for lamps having areas of 50 to 100 sq cm. This trend was reversed for 200 sq cm lamps. Decrements in probability of turn signal detection were associated primarily with lamp area. Rearview mirror discomfort glare was mainly a function of DRL intensity. Ratings of the degree of glare and the probability of electing to dim the mirror increased regularly with intensity from 500 to 2000 cd. A recommended DRL intensity distribution was developed based on the data.

• 
• Corporate Authors:

  Carlow Associates

  8315 Lee Highway
  Fairfax, VA  United States  22031

  National Highway Traffic Safety Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Kirkpatrick, M
  • Baker, C C
  • Heasly, C C
• Publication Date: 1987-8

Media Info

• Features: Figures; References; Tables;
• Pagination: 102 p.

Subject/Index Terms

• TRT Terms: Daytime running lamps; Experiments; Motor vehicles; Research; Traffic safety; Visibility
• Subject Areas: Highways; Research; Safety and Human Factors; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 00496555
• Record Type: Publication
• Source Agency: National Highway Traffic Safety Administration
• Report/Paper Numbers: HS-807 193
• Contract Numbers: DTNH22-85-C-07149
• Files: HSL, TRIS, USDOT
• Created Date: Aug 31 1990 12:00AM