Guidelines for Selection and Application of Warning Lights on Roadway-Operations Equipment

Roadway-operations equipment used for construction, maintenance, utility work, and other similar activities generally operate within roadway right of way. These vehicles and mobile equipment operate on all types of roadways, during day and night hours, and under all weather conditions. To improve motorist and work-crew safety, equipment must be readily seen and recognized and, therefore, warning lights are provided on the equipment to alert motorists of potentially hazardous situations. Amber warning lights have traditionally been used although lights of other colors are often added with the intent of helping the traveling public better see the equipment. Combinations of amber, blue, and white lights and other forms of warning lights (e.g., lighted bars, lighted "arrow sticks," strobe, LED, and alternating flashing) are used. There is a concern that this variety of lighting on roadway-operations equipment has evolved without adequate consideration of the effects on the awareness and responsiveness of motorists. There are no widely accepted guidelines for selecting warning lights on roadway-operations equipment that consider the type of equipment, weather conditions, day- and night-time operation, color of vehicle, and other relevant factors. Research is needed to develop guidelines for use by transportation agency personnel in selecting and procuring lights that will substantially enhance motorist awareness. The objective of this research is to develop guidelines for selection and application of warning lights to improve the conspicuity and recognizability of roadway-operations equipment used for construction, maintenance, utility work, and other similar activities. Roadway-operations equipment shall include vehicles and mobile equipment used in these activities.


  • English


  • Status: Completed
  • Contract Numbers:

    Project 13-02

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590

    American Association of State Highway & Transportation Officials

    444 North Capitol Street, NW, Suite 225
    Washington, DC    20001

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  USA  20001
  • Project Managers:

    Hanna, Amir

  • Performing Organizations:

    Virginia Polytechnic Institute and State University, Blacksburg

    Department of Aerospace and Ocean Engineering
    Blacksburg, VA  USA  24061
  • Principal Investigators:

    Gibbons, Ronald

  • Start Date: 20040729
  • Actual Completion Date: 20061231
  • Source Data: RiP Project 8999

Subject/Index Terms

Filing Info

  • Accession Number: 01463116
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 13-02
  • Files: RiP, USDOT
  • Created Date: Jan 3 2013 2:17PM