Abstract
The primary task of pavement markings is to provide a visual cue to drivers to assist them with vehicle position along a roadway and help them make a proper lane change decision. The objective of this study was to determine the safety effectiveness of wider pavement markings with regard to traffic safety. The study collected and analyzed crash data at 38 locations in the state of Idaho. In the United States, the default pavement marking width is typically 4 inches and the color is white or yellow. Before and after studies using comparison group and Empirical Bayes methods were applied to determine that if there was a relationship between the implementation of wider pavement markings and vehicle crashes. Safety performance functions (SPF) for run-of-the-road crashes (ROR) in Idaho for two-lane rural highways were also developed. This study concluded that there is a strong relationship between wider pavement markings width and a reduced number of ROR crashes especially fatal and serious injuries crashes. For this reason, the implementation of wider pavement marking widths by agencies along two-lane rural highways is encouraged to provide a long-term safety benefit for the motoring public. This study will recommend strategies for state DOTs to increase safety and suggest a need to revise the MUTCD definitions on marking widths. The research results showed that wide pavement marking implementation has the potential to reduce fatal and serious ROR crashes by 10.07 percent with an expected cost to benefit ratio of approximately 1:25.