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Emergency Vehicle Visibility and Conspicuity Study

NCJ Number
Date Published
August 2009
45 pages
This report analyzes emergency vehicle visibility and conspicuity (the feature of being conspicuous among other vehicles on the road) so as to guide and broaden efforts to improve roadway safety for all emergency responders and civilian drivers in the course of rapid responses by emergency vehicles.
One of the principal findings is the need for additional research on emergency vehicle visibility and conspicuity in the United States, with an emphasis on distinguishing them from civilian vehicles when traveling to emergency incidents and while at incident scenes. Other key findings are that the increased use of retroreflective materials holds great promise for enhancing the conspicuity of emergency vehicles; however, it is theoretically possible to "over-do" the use of retroreflective materials, which can interfere with drivers' ability to recognize other roadway hazards. In addition, fluorescent colors, especially fluorescent yellow-green and orange, provide higher visibility during daylight hours. Also, the use of contrasting colors can assist civilian drivers in recognizing a hazard amid the visual clutter of the roadway. One suggestion is to outline vehicle boundaries with "contour markings," using retroreflective material, especially on large vehicles. A related suggestion is to concentrate retroreflective material lower on emergency vehicles in order to optimize reflection from approaching vehicles' headlamps. For law enforcement vehicles, retroreflective material should be concentrated on the rear so as to maintain stealth when facing traffic or patrolling. The report emphasizes the importance of the visibility and conspicuity of emergency vehicles by reporting statistics on the prevalence of injuries and deaths among emergency service workers on U.S. roadways. 15 figures, 4 tables, 108 references, and appended Reflective Sheeting Identification Guide, background for chevrons on the rear of fire apparatus, and selected NFPA requirements for emergency vehicles

Date Published: August 1, 2009