What's the difference between a 'controlled' fire and a 'contained' fire?
They might sound similar but they have different meanings on how firefighters are making progress.
Firefighters work on a controlled burn during the Caldor Fire in Christmas Valley in South Lake Tahoe, California, U.S., on Thursday, Sept. 2, 2021.
( David Paul Morris/Bloomberg / Getty Images)
When listening to wildfire managers describe progress against large blazes, you might hear them talk about containment or the fire being under control.
They might sound similar, but they have different meanings.
As firefighters work to contain a fire, they are creating a fuel break around the perimeter. When you hear a fire might be "20 percent contained," it means they have completed a fire break around 20% of the edge. When a fire is "100% contained," it means the fuel break around the fire has been completed.
Fire officials say the fire break can include natural barriers or a manually constructed fire line.
Then when firefighters say the blaze is "controlled" or "under control," it means the fire is extinguished, including spot fires. Firefighters have also had the opportunity to strengthen the fire line to ensure any flare-ups won't cross the break.
Note that a fire can remain out of control while it is still contained.