An Exploration of Driver Perception Reaction Times Under Emergency Evacuation Situations

Driver behavior under emergency condition may be quite different from that under the normal conditions. Perception-reaction-time (or PRT) is an important parameter to reflect a driver's capability to maneuver in response to an event. Studies on PRT under normal condition have been widely conducted and AASHTO provides a recommended value for PRT (2.5 second). However, there are very few studies on PRT under emergency conditions (e.g. evacuation activity) in the literature. The objective of this study is to compare PRT values between normal and emergency conditions. With the help of a driving simulator a simulation scenario is used to create driving environments under both the normal and emergency evacuation conditions. A questionnaire survey is conducted to verify if the driving environment created in the lab truly reflects these two conditions from both subjective and objective aspects. In addition, three scenario sets are considered in the study to analyze variations of perception reaction time (PRT): (1) the driver experiences an unanticipated incident; (2) the driver experiences deceleration, and (3) the driver experiences acceleration. Experiments are carried out based on the SimWorld simulator by AutoSim Corporation. The experiments are divided into two phases. During first phase drivers (participants) operate under normal conditions. Then, drivers are told to watch video clips related to an emergency and the heart rate of the driver is recorded during the whole process of watching. The second phase starts when the heart rate value of a driver indicates that this driver comes into an emergency condition. The preliminary result indicates that the PRT under emergency conditions is different from that under the normal situation. The value of PRT under normal situation is greater than that under emergency evacuation situation. Moreover, the differences in PRT for acceleration and deceleration scenarios between normal and emergency are quite significant. The results from this study can help traffic engineers recalibrate traffic flow models. Additionally, the results will be helpful for the development of the simulation software for emergency evacuation.


  • English

Media Info

  • Media Type: DVD
  • Features: Figures; Photos; References; Tables;
  • Pagination: 15p
  • Monograph Title: TRB 89th Annual Meeting Compendium of Papers DVD

Subject/Index Terms

Filing Info

  • Accession Number: 01157062
  • Record Type: Publication
  • Report/Paper Numbers: 10-1453
  • Files: TRIS, TRB
  • Created Date: Jan 25 2010 10:39AM