14.2 Task Analysis of Rail-Highway Grade Crossings

14.2 Task Analysis of Rail-Highway Grade Crossings Traffic control devices play a valuable role in warning motorists of downstream rail crossings. Table 14.1 lists compliance issues and guidelines that influence whether motorists stop when warned of impending trains....

13.12 Determining Work Zone Speed Limits

13.12 Determining Work Zone Speed Limits Decisions about work zone speed limits need to account for road geometrics and the location of work zone features (e.g., lane closure tapers, work activity). If possible, keep work zone speed limits within 10 mph of normal...

13.10 Sign Legibility

13.10 Sign Legibility Factors that influence sign legibility include retroreflectivity, color, letter/number font, and location (e.g., roadside or overhead). Prismatic sheeting enhances sign retroreflectivity. Use of fluorescent colors increases sign visibility in...

13.8 Changeable Message Signs

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

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...