TUNNEL AND UNDERPASS LIGHTING PRACTICE IN USA

THE REPORT COVERS THE ILLUMINATION METHODS USED IN RECENT YEARS OR BEING PLANNED FOR USE IN FUTURE CONSTRUCTION. THE BASIC METHOD OF LONG TUNNEL LIGHTING IS BY COMMERCIALLY ABAILABLE LAMPS WITH AN ENCLOSED LUMINAIRE WHICH PROVIDES MECHANICAL PROTECTION AND CONTROLS THE DIRECTION OF INTENSITY OF THE LIGHT. LAMPS AT THE ENTRANCE MAY BE OPERATED AT MAXIMUM OUTPUT AND STEP REDUCTION IN THE LIGHTING IS EFFECTED BY CHANGING THE LIGHT OUTPUT OR REDUCING THE NUMBER OF LAMPS. FOR NIGHT OPERATION, THE CONTROLS AND CIRCUITS ARE ARRANGED TO OPERATE AT A LOWER LEVEL OF ILLUMINATION. OTHER TYPES OF LUMINAIRES DESCRIBED ARE THE FLUORESCENT LAMP MOUNTED IN A HARD, HEAT RESISTANT GLASS TUBE AND A SPECIAL FORM DEVELOPED IN CALIFORNIA GIVING UNIFORM WALL AND CEILING BRIGHTNESS AND FEATURING AUXILIARY REFLECTORS FOR LAMP-SHIELDING. A COMBINATION OF LIGHT SOURCES IS CONSIDERED ADVANTAGEOUS AND A HIGH INTENSITY SOURCE SUCH AS MERCURY IN COMBINATION WITH THE BASIC FLUORESCENT SYSTEM IS SUGGESTED. ONE OR MORE ROWS OF LUMINAIRES LOCATED NEAR THE JUNCTION OF WALLS AND CEILINGS CAN SATISFACTORILY LIGHT 2 AND 3 LANE TUNNELS. NINE LONGITUDINAL ROWS OF LIGHTS WILL BE USED FOR SOME ZONES OF THE 80 FT WIDTH (IN SOME SECTIONS) NEW MALL TUNNEL IN WASHINGTON, D. C. THE LIGHT DEPRECIATION FACTOR MAY BE FAIRLY HIGH AND DEPENDENT ON FREQUENCY AND THOROUGHNESS OF THE CLEANING AND RELAMPING PROGRAM. INVESTIGATIONS SHOW THAT HORIZONTAL NIGHT ROADWAY ILLUMINATION VARIES BETWEEN 3-20 FOOT-CANDLES. SUN SHIELDS ARE RECOMMENDED AS A MEANS OF REDUCING ENTRANCE ZONE LIGHTING REQUIREMENTS. UNDERPASSES IN RURAL AREAS ARE NOT USUALLY LIGHTED BUT LIGHTING IS NECESSARY IN URBAN AREAS. LOW WATTAGE WALL MOUNTING MERCURY LAMPS HAVE BEEN DESIGNED FOR USE IN UNDERPASSES AND SHORT TUNNELS. FLUORESCENT WALL-MOUNTED OR SUSPENDED LUMINAIRES HAVE ALSO BEEN USED.

  • Authors:
    • Thompson, J A
    • Fansler, B I
    • Ragland, J S
  • Publication Date: 1972-8

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Filing Info

  • Accession Number: 00221823
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 3 1973 12:00AM