AN INTERIM REPORT ON A STUDY OF DISABILITY VEILING BRIGHTNESS

FOR NONUNIFORM FIELDS OF VIEW AS FOUND IN ROADWAY LIGHTING WITH LARGE GLARE SOURCES PRESENT, THE STRAY LIGHT PRODUCES DISABILITY VEILING BRIGHTNESS (DVB) WHICH CAN ADVERSELY INFLUENCE VISIBILITY AND MUST BE TAKEN INTO CONSIDERATION WHEN EVALUATING ROADWAY LIGHTING SYSTEMS. THIS RESEARCH WAS DESIGNED TO: (1) DETERMINE THE DVB OF SELECTED ROADWAY LIGHTING SYSTEMS OF 1000-WATT LUMINAIRES, AND (2) DETERMINE THE EFFECT OF MOUNTING HEIGHT ON DVB FOR 400- AND 1000-WATT LUMINAIRES. THE DATA FOR ALL THE SYSTEMS TESTED WERE SUMMARIZED BY CONSTRUCTING CONTOURS BASED ON THE K-VALUES FOR EACH LIGHTING SYSTEM. FROM THE PATTERNS FORMED BY THE CONTOUR LINES OF THE DIFFERENT SYSTEMS, IT CAN BE SEEN THAT CHANGES IN MOUNTING HEIGHT DO NOT NECESSARILY CHANGE THE PATTERN AS TO FORM, BUT ONLY CHANGE THE INTENSITY. FOR A LOW MOUNTING HEIGHT, THE INTENSITY IS HIGHER THAN FOR A HIGHER MOUNTING HEIGHT. SYSTEMS WITH LUMINAIRES IN ONESIDE MOUNTING CONFIGURATIONS AND MEDIAN MOUNTING CONFIGURATIONS PRODUCE APPROXIMATELY THE SAME PATTERNS OF DVB. INTENSITY OF DVB AND PAVEMENT BRIGHTNESS IS GREATER FOR 1000-WATT LUMINAIRE SYSTEMS THAN FOR CORRESPONDING 400-WATT LUMINAIRE SYSTEMS. FLUCTUATION OF DVB IS GREATER FOR THE 400-WATT SYSTEMS THAN FOR THE 1000-WATT SYSTEMS. FOR A STAGGERED SYSTEM, A 1000- WATT SYSTEM WITH 50-FOOT MOUNTING HEIGHT PROVIDES BETTER CONDITIONS FOR VISION THAN A 400-WATT SYSTEM WITH 45-FOOT MOUNTING HEIGHT. FOR ANY OF THE 1000-WATT SYSTEMS THE LEVEL OF DVB APPEARS TO BE LOW ENOUGH NOT TO BE A CRITICAL FACTOR IN VIEW OF THE HIGH PAVEMENT BRIGHTNESS PRODUCED BY THE SYSTEMS.

• Supplemental Notes:
  • Res Rept No 75-5, 43 PP, 30 FIG, 4 TAB, 2 REF, 1 APP
• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 1600 E Lamar Boulevard
  Arlington, TX  United States  76011

  Texas State Department of Highways & Public Transp

  11th and Brazos Streets
  Austin, TX  United States  78701

  Department of Transportation

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  Bureau of Public Roads /US

  400 7th Street, SW
  Washington, DC  United States  20590
• Authors:
  • Rowan, N J
  • Jensen, H C
  • Walton, N E
• Publication Date: 1967-6

Subject/Index Terms

• TRT Terms: Brightness; Glare; Height; Luminaires; Pavements; Power; Street lighting; Visibility
• Uncontrolled Terms: Intensity
• Old TRIS Terms: Disabling glare; Highway pavement
• Subject Areas: Energy; Highways; Pavements; Safety and Human Factors;

Filing Info

• Accession Number: 00219929
• Record Type: Publication
• Files: TRIS, ATRI, USDOT, STATEDOT
• Created Date: Jan 16 1994 12:00AM