This guide accompanies the Vulnerability Assessment Scoring Tool (VAST) and explains how to use the tool. The tool was developed to help State DOTs, MPOs, and other organizations implement an indicator-based vulnerability screen. An indicator-based screen is one method for assessing vulnerability, and relies on two key premises:
- Vulnerability is a function of exposure, sensitivity, and adaptive capacity.
- Certain characteristics of assets can serve as indicators of their exposure, sensitivity, or adaptive capacity.
Thus, the approach involves collecting information about indicators of each vulnerability component and operationalizing that information into relative vulnerability scores. This can be done for any combination of stressors and asset types, and involves several steps: determining the scope of the vulnerability assessment (VAST Steps 1 and 2), selecting indicators (Step 3), collecting data about those indicators (Step 4), and devising an approach to convert raw data about indicators into scores (Step 5). The result is a set of vulnerability scores that can be used to rank assets by vulnerability or inform other analysis of the results (Step 6).
Review the contents of the guide for full instructions on accessing and using the tool.