OPTIMIZATION OF ROADWAY LIGHTING SYSTEMS

OBJECTIVE AND SUBJECTIVE STUDIES WERE CONDUCTED USING FULL-SCALE ROADWAY LIGHTING LABORATORY FACILITIES TO DETERMINE THE OPTIMUM GEOMETRIC CONFIGURATION OF ROADWAY LIGHTING SYSTEMS TO PRODUCE A SATISFACTORY DRIVING ENVIRONMENT FOR FREEWAY-TYPE FACILITIES. CONSIDERATIONS IN DETERMINING THE OPTIMUM GEOMETRIC CONFIGURATION WERE: (1) OBTAINING A MORE FUNCTIONAL SYSTEM, (2) REDUCING GLARE, (3) REDUCING THE OVERALL COST OF INSTALLATION, OPERATION, AND MAINTENANCE, AND (4) REDUCING THE NUMBER OF POLES TO REDUCE FIXED-OBJECT HAZARDS. IT WAS DETERMINED THAT A MORE ECONOMICAL AND FUNCTIONAL LIGHTING SYSTEM CAN BE OBTAINED BY INCREASING THE MOUNTING HEIGHT OF CONVENTIONAL MEDIUM DISTRIBUTION TYPE MERCURY VAPOR LUMINAIRES. IT WAS FOUND THAT 400-WATT LUMINAIRES MOUNTED AT 40 FT AND SPACED AT 200 FT APART PRODUCED THE MOST FUNCTIONAL SYSTEM FOR ROADWAYS WITH TWO AND SOMETIMES THREE LANES IN EACH DIRECTION. TYPE III 1,000-WATT MERCURY VAPOR LUMINAIRES MOUNTED AT 50 FT AND SPACED 300 FT APART PRODUCED THE MOST FUNCTIONAL LIGHTING SYSTEM FOR ROADWAYS WITH THREE TO SIX LANES IN EACH DIRECTION. THE BENEFITS DERIVED FROM HIGHER MOUNTING HEIGHTS ARE: (1) REDUCTION IN DISCOMFORT DUE TO GLARE, (2) IMPROVED UNIFORMITY OF ILLUMINATION, AND (3) GREATER SAFETY AND LOWER COST OF INSTALLATION AND OPERATION DUE TO FEWER LUMINAIRES PER MILE.

Media Info

  • Media Type: Print
  • Features: Figures; References;
  • Pagination: pp 34-47
  • Monograph Title: Lighting, visibility and driving
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00220134
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Jul 29 1994 12:00AM