This comparative study evaluates the influence of an amber blackout on driver response along an approach to a signalized T-intersection. About 20 hours of traffic data were recorded during the amber blackout, which was the result of a faulty signal display system, where drivers approaching a signalized intersection after the termination of the green signal encountered no amber light indication for the entire duration of 3 seconds before the onset of the all-red display. An identical timeframe of traffic data from the following day during regular amber light operation was available to assess driver response during this critical signal phase-change period. The findings indicated that during the amber blackout, drivers would decelerate initially to slow down their vehicles and then take advantage of the blackout by violating the red signal during the first 2-3 seconds as far as traffic flow conditions permitted. The increase in red-running violations could be attributed to drivers who could have crossed during amber slowing down their vehicles that subsequently crossed during red. Also, drivers located further upstream who deliberately violated the red and drivers who could have stopped but chose to violate the red signal contributed to such an increase. These results confirm the importance of an amber signal after the termination of green and emphasize the importance of adequately illuminating signal lights.

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    The Boulevard, Langford Lane
    Kidlington, Oxford  United Kingdom  OX5 1GB
  • Authors:
    • Lum, K M
    • Tan, Y W
  • Publication Date: 2003-9


  • English

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Filing Info

  • Accession Number: 00963382
  • Record Type: Publication
  • Files: TRIS, ATRI
  • Created Date: Sep 30 2003 12:00AM