ATSSA: Improving Driver Behavior with Infrastructure Safety Countermeasures

20 Improving Driver Behavior with Infrastructure Safety Countermeasures T he complexity of the driving conditions in a work zone can lead to driver errors that result in potential risk to work-zone workers themselves. Roadway safety infrastructure improvements can help increase the visibility and the overall safety within the work zone to help minimize driver error. Intrusion alarms, for example, notify work-zone workers when an errant vehicle has left the travel lane and has entered the work area. This audible notification provides an additional window of time for workers to safely move to a protected location. Some alarms can also sound when impacted or when a detector is triggered. CASE 13: Alarms, Platforms, and Temporary Attenuators in Work Zones Figure 36. This portable worker alert system provides a warning to road workers in the event a vehicle enters the work zone (Image: Astro Optics LLC – a TAPCO company) Protection for work-zone workers who install and remove signs, drums, and other devices can sometimes be provided via an appropriate, safe truck platform. This worker-protection method of placing or retrieving traffic control devices on roadways helps reduce worker exposure to traveling vehicles and thereby reduces the potential for work-zone incidents and crashes. Temporary attenuators can be used for road construction projects to protect motorists and work-zone workers. One example is a truck-mounted attenuator (TMA). TMAs are energy-absorbing safety devices that attach to the rear of a work truck to help prevent rear-end collisions between slow-moving or stopped work vehicles and traveling vehicles. As a protective shield, TMAs benefit workers and the motoring public when construction or maintenance activities occur adjacent to active traffic lanes. Figure 37. A TMA following impact by an automobile (Image: TrafFix Devices Inc.) An analysis of potential rear-end crashes in mobile and short-duration operations found TMAs to be highly effective in reducing the severity of rear-end crashes and the associated crash costs. In California recently, both a California Department of Transportation (Caltrans) employee and a motorist were spared a severe outcome when a passenger vehicle traveling at a high rate of speed departed its travel lane and struck a Caltrans truck involved in snow removal operations in the left shoulder of Interstate 80. The photos in Figure 37 show the results of that crash. ■