Donning orange fire-resistant suits and carrying 60 pounds of support gear on their backs, they're on the front lines of the wildfires with chain saws and hand tools, clearing brush or setting backfires to stop the flames from spreading.
But they aren't officially firefighters -- they're prison inmates.
With help from the California Department of Forestry and Fire Protection (Cal Fire) and the Los Angeles County Fire Department, the state Department of Corrections and Rehabilitation jointly operates 43 adult conservation camps, or fire camps, throughout the state, according to the corrections department.
They're called conservation camps because that is part of their purpose: Inmates maintain hiking trails, clear flood channels and reduce fire danger by cutting brush or large stands of trees when there are no fires ongoing.
"The inmates are all doing some form of conservation work every day that they are not on a fire line," Bill Sessa, a spokesman for the corrections department, told CNN.
Inmates with minimum-custody status, meaning those with the lowest security risk, can volunteer for the program, according to Sessa. He said inmates are screened and must be physically fit for rigorous activity, disciplined and willing to work on a team and take responsibility.
Those who are selected to participate in the program are permanently assigned to one of the camps, where they're supervised by corrections officers, and stay there year-round, Sessa said. There are around 3,800 inmates housed at the camps, he said.
The camps are more informal than prisons, Sessa said, as there are no electric fences and inmates stay in dorms. The relationships between the staff and inmates are more casual.
"They're fundamentally different, and that's one of the attractions that makes inmates apply to them," he said of the camps.
On the front lines
After being selected for the program, the inmates participate in a two-week training program where they take part in physical training and are taught firefighting techniques by Cal Fire staff.
When responding to wildfires, the inmates work in crews of 12 to 14 people under the direction of professional fire captains from Cal Fire or the LAFD, Sessa said.
"Our crews do a very specific job. They don't get into a highlight reel or (TV) airtime, they don't fly a helicopter or drive a fire truck. ... They cut containment lines," he said, referring to using techniques such as clearing brush to keep a wildfire contained within boundaries.
Sessa described each crew as a line in which everybody has a job related to the person in front or behind them with the goal of containing or stopping the fire.
"These people are in the front line because their job is to get ahead of the fire," Sessa said. "Our crews are quite often put between the homes and the fire trying to cut containment lines."
He said there are crews working on around 15 of the wildfires ravaging California.
"It's been quite a while since I can remember that we have had this many fires moving this fast," he said. "Crews often work 24 straight hours and then get 24 hours of rest. This firestorm -- we had crews that worked 72 straight hours.
When you get into these prolonged circumstances, everybody's concern is how to give these guys some rest, because you can't go an entire summer like this. The 72 hours, they did it because they had to do it. It's not something we would prefer them to do."
Across the state, Sessa said there are 1,700 inmates on the front lines of the catastrophic wildfires, and the rest are helping in other ways.
"Every inmate we have right now is either on a fire line, on a rest period from being on a fire line, or providing backup to fire protection somewhere and ready to go to a fire," he said. "In a firestorm like the one we have now, we move crews from all over the state to get them to where they're needed. We also have to move crews around to make sure we don't leave areas unprotected."
Sessa said the goal of the program isn't just to put out fires, and that most of the inmates who volunteer have no intention of becoming firefighters.
"The value of this program is it teaches people life skills that most of us take for granted but many of them came to prison without," he said. "They learn discipline and to show up on time, and some leadership.