Updated: 6:35 a.m. July 21

First discovered: 35 hours ago, 7:33 p.m. July 19

Initial location: Black Rock Springs Road and Hwy 395, Poverty Hills, Inyo County, Calif.

Fire unit: Unified Command: Cal Fire San Bernardino Unit, California Highway Patrol, Inyo National Forest and the Inyo County Sheriffs Department

Fire type: Wildfire

Fire name: Rock Fire

Rock Fire initially started 7:33 p.m. July 19 at Black Rock Springs Road and Hwy 395, Poverty Hills in Inyo County, California.

As of Tuesday morning, 2,500 acres of land had been destroyed by it, an increase of 705 acres since the last update. By Tuesday morning, 5% of this wildfire was brought under containment. At this time, there is no information available on the cause of the fire.

Fire containment

Understanding what 5% containment means

Containment indicates what percentage of the fire perimeter has been surrounded by a control line. In this case, it means that 5% of the wildfire is contained from spreading, while 95% is still uncontrolled.

Containment is part of a larger plan for managing a wildfire. It is normally expressed as a percentage and it refers to how much of the fire perimeter has been surrounded/enclosed by a control line that firefighters create. The containment percentage indicates a certain level of control, but it doesn’t always correlate to safety level. Also, it’s important to note that containment doesn’t mean a fire is out.

How is containment measured?

The incident’s central command constantly receives progress reports from firefighters on the ground. As the fireline is constructed, inspected or reinforced, mappers record those details to adjust the containment percentage. The percentage tells the public how much of the fire perimeter is believed to not go beyond the control lines.

Source: Cal Fire