SEEING ON THE HIGHWAY, RECENT RESEARCHES ON LIGHTING REQUIREMENTS

SINCE 1930 THERE HAS BEEN A 32 PER CENT INCREASE IN NIGHT TRAFFIC FATALITIES, WHEREAS DEATHS DURING THE DAYTIME HAVE DECREASED 4 PER CENT. A SUBSTANTIAL MAJORITY OF NIGHT ACCIDENTS ON RURAL HIGHWAYS OCCURS ON A VERY SMALL PERCENTAGE OF THE TOTAL HIGHWAY MILEAGE. POOR VISIBILITY PROVED TO BE ONE OF THE MOST IMPORTANT SINGLE FACTORS IN THE ABNORMAL HAZARD AT NIGHT. EXPERIENCE INDICATES THAT ON URBAN STREETS AND ON THE MORE DANGEROUS PORTIONS OF HIGHWAYS, IMPROVED ILLUMINATION HAS REDUCED NIGHT ACCIDENTS ONE-THIRD TO ONE-HALF, AT A COST LESS THAN ONE-THIRD OF THE LOSSES FROM THE ACCIDENTS PREVENTED BY THE LIGHTING. THE AVAILABLE DATA SUGGEST THE DESIRABILITY OF OBTAINING LARGER SCALE EXPERIENCE FOR THE MORE COMPLETE ANALYSIS OF THE EFFECT OF LIGHTING UPON NIGHT ACCIDENTS AND TRAFFIC VOLUME ON HEAVILY TRAVELED AND HAZARDOUS HIGHWAYS. EXTENSIVE RESEARCHES HAVE FOR THE FIRST TIME GIVEN US THE INSTRUMENTS AND TECHNIQUE FOR MEASURING THE END-PRODUCT, VISIBILITY, AS AFFECTED BY COLOR OF LIGHT, GLARE, LIGHT DISTRIBUTION, PAVEMENT BRIGHTNESS, AND OBSTACLE BRIGHTNESS. STARTLING ADVANCES HAVE COME ABOUT IN LIGHT SOURCES AND THEIR CONTROL TO PROVIDE THE MAXIMUM SEEING AND SAFETY PER DOLLAR OF TOTAL COST. ON A VERY HIGH PERCENTAGE OF THE HIGHWAY MILEAGE THE LOWER TRAFFIC DENSITY AND ACCIDENT EXPERIENCE INDICATE THAT FIXED LIGHTING WOULD BE UNECONOMIC. MORE ADEQUATE MOTOR CAR HEADLIGHTS AND THEIR PROPER USE WILL HAVE TO BE DEPENDED UPON FOR BETTER VISIBILITY AT NIGHT. NEW DATA HAVE RECENTLY BEEN ADDED TO THE AVAILABLE KNOWLEDGE OF THE RELATION BETWEEN VISIBILITY DISTANCE AND HEADLAMP BEAM CANDLEPOWER UNDER TYPICAL DRIVING CONDITIONS. MEASUREMENTS HAVE BEEN MADE OF THE EFFECT UPON VISIBILITY DISTANCE OF VARIATIONS IN SPEED, GLARE, AND REFLECTION FACTOR OF OBSTACLES. OF PARTICULAR SIGNIFICANCE ARE DATA OBTAINED WITH OBSERVERS UNAWARE OF THE FACT THAT THEY WERE ENGAGED IN A TEST, PROVIDING FOR THE FIRST TIME QUANTITATIVE INFORMATION ON THE EFFECT OF THE DRIVER-ATTENTION FACTOR. /AUTHOR/

  • Supplemental Notes:
    • Vol 17, ParT I, PP 420 - 434, 5 FIG, 13 PHOT, 12 REF
  • Authors:
    • Reid, K M
    • Dickinson, H C
    • Morrison, R L
    • Lauer, A R
    • Greenshields, B D
    • Holland, M
    • Brown, V J
  • Publication Date: 1938

Media Info

  • Monograph Title: Proceedings of the Seventeenth Annual Meeting of the Highway Research Board Held at Washington, D.C. November 30, December 1, 2, 3, 1937. Part I
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00221297
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 15 1971 12:00AM