Systemic Safety Project Selection Tool

EXAMPLE 5. New York State Department of Transportation Evaluation of Curve Radii as a Potential Risk Factor – Long Description

Example 5 shows the results of analyzing curve radius as a risk factor. The horizontal axis represents the lengths of curve radii on undivided, rural, two-lane state highways with a posted speed limit of 55 miles per hour in four categories. The four categories are: 100 to 300 feet, 301 to 500 feet, 501 to 700 feet, and 701 to 959 feet. The vertical axis represents percentages ranging from 0% to 14%. Two bars representing percentage are shown for each category of curve radius length. One of the bars represents the percent of lane departure crashes that occurred on a curve within the radius range, and the other represents the percent of curves on the state highway system that are within the radius range.

12 percent of the lane departure crashes occurred on a curve within the 100 to 300 foot radius range. 7 percent of the curves on the state highway system are within the 100 to 300 foot radius range.

12 percent of the lane departure crashes occurred on a curve within the 301 to 500 foot radius range. 10 percent of the curves on the state highway system are within the 301 to 500 foot radius range.

7 percent of the lane departure crashes occurred on a curve within the 501 to 700 foot radius range. 6 percent of the curves on the state highway system are within the 501 to 700 foot radius range.

4 percent of the lane departure crashes occurred on a curve within the 701 to 959 foot radius range. 5 percent of the curves on the state highway system are within the 701 to 959 foot radius range.