The Surface Safety Risk Index is a method used to evaluate the severity of risks associated with runway safety events. This index employs modeling techniques to assign risk weights based on the outcomes of such events, including aircraft damage, injuries, and fatalities. The weights are determined by their proximity to a potential fatality, acknowledging both lives saved and instances of minimal aircraft damage. Developed by the U.S. Federal Aviation Administration (FAA), this index is part of the Surface Safety Metric (SSM). The SSM aims to identify the most critical risks present in the runway environment more accurately. Unlike earlier metrics that focused solely on the number and severity of runway incursions, the SSM considers all relevant events occurring in this area. Essentially, the Surface Safety Risk Index serves as the methodology for assessing the severity of these events.
