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SpeedGuard Radar Speed Reporting System--NE

Status: Complete

Description: The SpeedGuard radar speed reporting system is a speed monitoring display which informs drivers of their speeds and thereby encourages them to slow down if they are traveling above the speed limit. The objective of the system is to reduce the speed of traffic and increase speed limit compliance. Statistically significant reductions in speeds and improvements in the uniformity of speeds were observed in both passenger cars and non-passenger cars after the deployment of the SpeedGuard system. The 85th-percentile speed, upper limit of the pace, and mean of the highest 15 percent of speeds were reduced by 4 or 5 mph and dropped to or below the 55-mph speed limit. The percentages of passenger cars and non-passenger cars complying with the 55-mph speed limit increased 17 and 15 points to 91 and 90 percent, respectively. The system proved to be effect at reducing speeds and increasing speed uniformity in the study context. It should be noted that data collection included only 7 hours of data after system deployment, and no data was available with respect to the persistence of the speed reductions farther downstream.

Report: MwSWZDI-2000-McCoy-Speed_Display.pdf 267 kb (published 2000)

State conducting research: Nebraska


  • Speed Measurement Labs


  • McCoy, Pat (University of Nebraska, Lincoln)

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