examine those scores and determine the areas with the highest rates of injury. This is done using the following steps: 1. Map the sliding windows analysis results for each mode (as well as for commercial vehicles) individually. 2. For each mode, determine the threshold score required to be included in the HIN. This step eliminates streets that have a lower crash density, thereby prioritizing streets that have higher crash severities and frequencies. 3. With a HIN created for each mode, create an overall HIN, comprising any segment that is on one or more modal HIN. The goal of the HIN threshold setting process is to independently settle on a sliding windows score for each mode, then identify key corridors where risk is highest, and create a network that covers a selective set of city streets but a relatively large share of crashes, with an emphasis on KSI crashes. These scores differ by mode and location in some instances due to the differences in the number of crashes. For example, a score of 10 may be high for the pedestrian network, but relatively low for a motor vehicle network, as there are so many more motor vehicle crashes than pedestrian crashes. A segment that meets or exceeds the weighted crash score threshold noted for each mode, below, were included in mode-specific HIN and the overall HIN. The threshold scores used for the Fort Worth Safety Action Plan are listed below.
Pedestrian: 5
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Bicycle: 4
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Motorcycle: 8
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Motor Vehicle: 50
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▪ Commercial Motor Vehicle: 8 Comparing the fraction of crashes – especially KSI crashes – that are on the HIN against the fraction of roads that make up the HIN (by roadway centerline mileage) illustrates how a small subset of roads account for a disproportionate share of crashes, especially KSI crashes.
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