As wildfires spread across Los Angeles, authorities are struggling to contain the blazes, which the public can track via CAL FIRE, a web service provided by the state’s Department of Forestry and Fire Protection. As of late Thursday, the Sunset fire in Hollywood Hills, which broke out on Wednesday, has been fully contained, while five other fires—including the first and largest Palisades fire as well as the Eaton, Hurst, Kenneth, and Lidia fires—remain active and uncontrolled (threatening to destroy life, property, and natural resources). [time-brightcove not-tgx=”true”] But what does it mean for a fire to be 0% contained—as is the case currently for the Eaton and Kenneth fires—or 6% contained like the Palisades fire, 10% contained like the Hurst fire, or 60% contained like the Lidia fire? Read More: Your Questions About Wildfire Smoke and Health, Answered The National Wildfire Coordinating Group (NWGC) defines wildfire containment as “the status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop the fire’s spread.” These control lines, according to a CAL FIRE factsheet on the 2021 Caldor fire, can be natural like rivers or man-made like dug-out firebreaks.