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Evaluation of traffic behavior in response to alternative police lighting
Travis Terry1, Vikki Fitchett1, Ronald Gibbons1
1Virginia Tech Transportation Institute, 3500 Transportation Research Plaza, Blacksburg, VA, 24060, United States.
Abstract:
More than 1500 U.S. law enforcement personnel fatalities occurred from 2007 to 2016, with 39 % of these related to automobile crashes. This study looked at various types of lighting on police vehicles to determine if changes made to the visibility of a police vehicle can impact the surrounding traffic behavior and increase safety for both law enforcement and the general public. Unmarked and marked police vehicles were positioned behind a civilian vehicle on the shoulder of five different multi-lane highways in Virginia, simulating a routine traffic stop. The data collected indicated that more lighting and the use of red in a light bar impact traffic behavior in terms of merging and speed when passing a police vehicle. The benefits may be attributed to the symbolic influence of red as denoting a different type of emergency than a traffic stop in addition to red's chromatic contrast against the blue sky during the daytime.

