Acceptability of Countdown Signals at an Urban Signalized Intersection and their Influence on Drivers Behaviour

  • Robert Rijavec
  • Jure Zakovšek
  • Tomaž Maher
Keywords: signalized intersection, countdown signal, start-up lost time, headway


There are different factors that affect driver’s behaviour at an urban signalized intersection. Complementary countdown signal heads can be used to inform the driver about the traffic light phase status. In the research presented in this paper, we explored how a countdown signal affects the driver’s reaction. We focused on the analysis of red/amber, red and amber running violations. We also observed and measured traffic flow start-up lost time and headway per cycle. Measurements took place in Ljubljana at a four-way intersection where two countdown signal heads are installed that face different directions. We used the “on-off-on” approach, using video surveillance and detection technology. According to the results of the investigative questionnaire, more than 84% of the surveyed drivers expressed positive opinion about the device. Analyses of field-test results have shown that the red and/or amber running violation rate is higher when the device is turned off. The results of the paper suggest that the countdown device had very little effect on the capacity of an urban signalized intersection.


Jelušić, N., Anžek, M., Ivanković, B.: Information Source Quality in Intelligent Transport Systems, Promet Traffic & Transportation, Vol. 22, 2/2010, pp.125-131

Craig, N., Renatus, N.M., Edward, K.S., Elizabeth, K.B., Judson, M.: Evaluation of alternative traffic light change anticipation system, Accident Analysis & Prevention, Vol. 29, Issue 2, 1997, pp. 201-209

Lum, K. M., Halim, H.: A before-and-after study on green signal countdown device installation, Transportation Research Part F: Traffic Psychology and Behaviour, Vol. 9, Issue 1, 2006, pp. 29-41

Yu-Chiun, C., Chien-Hua, C.: Driver responses to green and red vehicular signal countdown displays: Safety and efficiency aspects, Accident Analysis & Prevention, Vol. 42, Issue 4, 2010, pp. 1057-1065

Li, K., Dong, S., Sun, J., Yu, X.: Study on the influence of signal countdown device on traffic safety of intersections, Proceedings of 2009 International Conference on Measuring Technology and Mechatronics Automation, Zhangjiajie, Hunan, China, Retrieved on 14. 4. 2011, from

Limanond, T., Prabjabok, P., Tippayawong, K.: Exploring impacts of countdown timers on traffic operations and driver behaviour at a signalized intersection in Bangkok, Transport policy, Vol. 17, Issue 6, 2010, pp. 420-427

Žura, M., Maher, T., Rijavec, R., Strah, B., Kostanjšek, J., Marsetič, R., Logar, D.: SITSA-C, Slovenian ITS Architecture - Module Roads: Actual Development of Intelligent Transport Systems and Services, University of Ljubljana, Faculty of Civil and Geodetic Engineering, Ljubljana, 2005, pp. 98 (in Slovene). Retrieved on 14. 4. 2011, from

Baglivo, A.J.: Mathematica Laboratories for Mathematical Statistics: Emphasizing Simulation and Computer Intensive Methods, Society for Industrial and Applied Mathematics, Philadelphia, USA, 2005, pp. 123-125.

Highway Capacity Manual, Transport Research Board, National Research Council, Washington D. C., USA, 2000, Ch. 7: 7-1 – 7-13.

Highway Capacity Manual, Transport Research Board, National Research Council, Washington D. C., USA, 2000, Ch. 8: 8-28.

Sever, D., Dobovšek, M.: Acceptability of HCM 2000 methodology for traffic dimensioning of signalized intersections in Slovene urban environment, Gradbeni vestnik, Vol. 54, 2005, pp. 273-278 (in Slovene)

Chen, H., Zhou, H., Hsu, P.: What do We Know about Signal Countdown Timers? ITE Journal on Web, Vol. 2, 2009, pp. 72-76

Tollazzi, T., Renčelj, M., Rodošek, V., Zalar, B.: Traffic Safety of Older Drivers in Various Types of Road Intersections, Promet Traffic & Transportation, Vol. 22, 3/2010, pp. 193-201

Dobovšek, M., Sever, D.: Dimensioning of Signalized Intersections in Realistic Urban Environment, Promet Traffic & Transportation, Vol. 17, 2005, pp.143-148

Cvitanić, D., Lozić, I., Breški, D.: An analysis of intersection traffic signal warrants, Promet Traffic & Transportation, Vol. 17, 2005, pp. 25-32

How to Cite
Rijavec R, Zakovšek J, Maher T. Acceptability of Countdown Signals at an Urban Signalized Intersection and their Influence on Drivers Behaviour. Promet [Internet]. 1 [cited 2024Mar.1];25(1):63-1. Available from: