Slow Down! TTI Researchers Recommend Strategies for Slowing Drivers Around Work Zones

Making drivers comply with work zone speed limlits can be a difficult task. In 2000, there were 9500 crashes within a work zone and speed was the major cause in 42% of those crashes. The problem is trying to get people to slow down. Texas Transportation Institute (TTI) has conducted extensive research with TxDOT and other DOTs around the country to determine what makes drivers the most responsive to their speed. In a TxDOT sponsored project conducted by Brewer and his research team to make recommendations on strategies and devices to improve compliance with work zone speed limits (WZSL). TTI’s team conducted an extensive literature review, surveyed TxDOT and other DOT personnel around the nation, and field tested three devices, orange-border speed limit signs, speed display trailers, and portable changeable message signs with radar, to determine their effectiveness in reducing driver speed. Results from their field tests indicated that devices displaying a driver’s speed increased compliance rates by 10 to 27 percent points compared to when the devices were not used. Using these results, TTI produced recommendations for inclusion in TxDOT’s Work Zone Safety and Mobility Manual, including a flowchart to aid project engineers in deciding which devices and strategies to use in a particular work zone for maximum effectiveness.