The Fire Behavior Index (FBI) is a Technosylva metric which quantifies the potential intensity, severity, and spread of a new fire. By integrating both Flame Length and Rate of Spread, it provides a single, comprehensive metric for assessing fire behavior.
FBI values are dynamic and can fluctuate rapidly based on fuel type and changing weather conditions, such as temperature, relative humidity, wind speed, and rainfall. As a result, it is not a static measure and evolves in response to environmental changes.
The closest Canadian equivalent is Head Fire Intensity (HFI).