Over the last several years, Battelle has conducted studies with the U.S. Department of Transportation (DOT) to better understand how axial cracks develop under different operating conditions. Optimizing both physics-based models and empirical data, researchers created a leading-edge tool to predict crack growth under different operating scenarios. Use of this tool, entitled PipeAssess PI, can help operators reduce reliance on frequent, unoptimized inline inspection and hydrostatic tests, as well as reduce maintenance costs by informing prioritization of repair and replacement decisions.