13.8 Changeable Message Signs The purpose of changeable message signs is to communicate important messages succinctly. Keep display messages to a maximum of two phases. Avoid splitting information across phases, use a consistent format for calendar dates, and make...
13.2 Overview of Work Zone Crashes Young male motorists (ages 25 – 34) are most likely to be involved in work zone crashes. Knowledge of work zones and how they influence safety is valuable for reducing crash risk. Table 13.1 provides general guidance on structuring...
16.6 Rumble Strips Rumble strips are raised or grooved indentations on the shoulder or median. When a vehicle departs its lane and travels over rumble strips, motorists hear an audible alert and experience a vibrating sensation that warns their vehicle has departed...
6.12 Signs on Horizontal Curves Use curve warning signs to communicate downstream changes in horizontal alignment to motorists. Signs need to include a directional arrow that indicates if a curve bends to the left or right. Advisory speed signs can also be used. Table...
6.10 Countermeasures to Improve Pavement Delineation Good pavement surface markings allow drivers to (a) detect and recognize curves earlier, (b) reduce speeds appropriately, and (c) adjust their lateral position. Table 6.3 provides design guidance for markings. Table...
