Craig, Curtis

This flyer was created as part of Report 2023-04, "Development of a Mobile App for Reporting Work Zone Intrusions," published January 2024.

Work zone intrusions represent a significant safety risk to workers. To help better understand these situations, the Minnesota Department of Transportation partnered with the University of Minnesota to create a method to document intrusion events. This information provides a deeper understanding of the circumstances under which these events occur and enables data-driven decision making when considering ways to reduce or mitigate work zone intrusions. This work focuses on the development of a mobile smartphone app that allows workers to report intrusions from the field immediately after they occur, allowing for timely and accurate intrusion reporting. The work zone intrusion mobile app is developed using an iterative, user-centered design process that solicits feedback from work zone personnel, supervisors, and work zone safety stakeholders at every step in the process. The app uploads completed report data to the existing eSAFE system, allowing for a single repository of collected intrusion report data. To support deployment of the system, training workshops and supporting training and communications materials are created for distribution among users. Throughout the development and deployment of the app, user feedback shows that the app is easy to use and well liked.

Decisions made regarding driver sight distance at rural intersections are complex and require considerations for safety; efficiency; and environmental factors. Sight distance; cross-traffic velocity; and vehicle placements significantly affect driver judgment and behavior at these intersections. A series of rural; two-lane thru-STOP simulated intersections with differing sight distances and traffic speeds were created and then validated by county and state engineers. Experimental data from 36 participants in a time-to-collision (TTC) intersection crossing judgment task and a rural highway thru-STOP intersection driving simulation task was analyzed to clarify the influence of rural thru-STOP intersection characteristics on driving performance and decision-making. Results demonstrated that longer sight distances of1;000 ft. and slower crossing speeds (i.e.; 55 mph) were more accommodating for participants attempting to select gaps and cross from the minor road; corresponding with (1) lower mental workload; perceived risk; difficulty; and anxiousness; and (2) better performance in terms of estimated crash rate; and larger TTCs. Second; longer distances of 1;000 ft. appear to aid drivers' responsiveness on the main road approaching an intersection; specifically when another driver on the minor road runs the stop sign. Minor road drivers positioned close to the roadway at the stop sign; compared to standard stop bar placement; tended to help reduce the speed of main road drivers. Overall;results demonstrated a systematic improvement in the performance of both minor and major road drivers with the implementation of a1;000-foot sight distance at rural thru-STOP intersections.

sed a multifaceted approach to improving compliance to the Minnesota crosswalk law in Saint Paul; Minnesota; including: (1) education; (2) measurement; (3) enforcement efforts; (4) social norming; and (5) engineering treatment. The multifaceted activities were planned and implemented in Saint Paul with city traffic engineers and enforcement officers. The study initially observed 32% yielding and frequent multiple threat passing at 16 unsignalized; marked crosswalks throughout Saint Paul; measured through staged pedestrian crossings by the research team. A program was implemented that used a phased treatment approach of disseminating educational materials; conducting four waves of high visibility enforcement (HVE); displaying yielding averages on feedback signs across the city; and introducing low-cost engineering solutions through in-street signs. The results demonstrated a significant impact from education; HVE; and engineering to increase yielding to as high as 78% at enforcement sites and 61% at untreated sites. Multiple threat passing was also reduced. Overall; the study demonstrated that the HVE program and combined low-cost engineering were effective at improving compliance to the crosswalk law.

While necessary for roadways; work zones present a safety risk to crew. Half of road workers deaths between 2005 and 2010 were due to collisions with motorists intruding on the work zone. Therefore; addressing intrusions is an important step for ensuring a safe work environment for crewmembers. However; a recent research synthesis at the Minnesota Department of Transportation found that few states had an explicit method for systematically collecting work zone intrusion data. The purpose of this work zone intrusion interface design project was to design an efficient; comprehensive; and user-friendly reporting system for intrusions in work zones. A user-centric; iterative design process was employed to design an adaptable web-based and paper report to account for simple documentation of intrusions not deemed a threat to worker safety and a detailed report for more thorough documentation of serious intrusion events. Final recommendations include organizational changes and support to encourage workers to complete the form and provide valuable data to the state.

Work zones present an increased risk to drivers and the work crew. To mitigate these risks; this study investigated the potential effects of in-vehicle messages to communicate work zone events to the driver. The researchers conducted literature reviews on risks imposed by work zones; along with design guidelines for any in-vehicle messaging system. The researchers then conducted a work zone safety survey to illustrate driver attitudes in Minnesota toward work zones; along with smartphone use and in-vehicle messages through smartphones. The survey found that a significant number of drivers make use of smartphones in the automobile; and they placed these smartphones in various locations throughout the vehicle. The survey was followed by a driving simulation study that tested drivers in two different types of work zones. Participants drove through these work zones three times; each with different messaging interfaces to communicate hazardous events to the driver. The interfaces included a roadside; portable changeable message sign; a smartphone presenting only auditory messages; and a smartphone presenting audio-visual messages. There was better driving performance on key metrics including speed deviation and lane deviation for the in-vehicle message conditions relative to the roadside signs. Furthermore; drivers reported significantly less mental workload and better usability; work zone event recall; and eye gaze behavior for the in-vehicle conditions relative to the roadside sign condition.