Driver Feedback on Monetary Penalty and Its Impact on Work Zone Speed

Across the nation, one work zone fatality occurs every 10 h (about 2.3 per day) and one injury, every 13 min (110 per day). Speed limit compliance in and around work zones concerns transportation agency officials because excessive speeds have proved to be primary causes of crashes in work zones. As much as 25% of fatal crashes in work zones may have involved high speeds. Research was conducted with the use of a changeable message sign with radar (CMSR) at one work zone location on a four-lane, divided highway in Arizona. The CMSR, which was triggered by radar-detected speed, provided feedback to drivers about the amount of their potential traffic fine. A review of the literature indicated that this type of feedback has received only limited study. The CMSR alternated one speed feedback message, “Your Speed XX mph,” with another, “Possible Fine $XXX.” The dollar amount varied according to the speed of the vehicle. The coupling of speeding-fine feedback with alternating feedback on vehicle speed led to an observed reduction of speeds in the tested work zone. Reductions in mean speeds were modest, at approximately 4 mph. However, the impact on excessive speeders was significant. The number of speeders that traveled 5 and 10 mph, or more, above the speed limit decreased by one-fourth. At the extreme speeds of 15, 20, and 25 mph over the speed limit, the number of speeding vehicles was reduced in each case by half.