Evaluation of Traffic Control Devices: Fourth-Year Activities

This project was established to provide a means of conducting limited scope evaluations of numerous traffic control device issues. During the fourth year of the project, researchers completed assessments of five issues: developing an automated process for identifying the start and end of no-passing zones, developing guidelines for the use of pedestrian countdown signals, evaluating the performance of lead-free yellow thermoplastic pavement markings, developing improved guidelines for accessibility issues associated with traffic signalization, and continuing development of the Work Zone Impacts Handbook. The automated nopassing zone activity developed a prototype method of using Global Positioning System (GPS) coordinates to identify the start and end of no passing zones based on vertical alignment. The activity on pedestrian countdown signals synthesized available information to develop some initial guidelines. The signal accessibility and work zone impacts¿ activities are producing separate documents that address those issues.