A drone equipped with thermal imaging reveals where flames are concentrated inside of a burning house, during a training exercise. (Roswell Flight Test Crew)
When firefighters were quelling the last of Oakland's catastrophic Ghost Ship warehouse fire on the morning of December 3, they used a relatively new tool: an unmanned aerial vehicle, or drone.
The small UAV, barely noticeable above the smoking ruins, belonged to the Alameda County Sheriff's Office, and was equipped with a thermal imaging camera. It enabled firefighters to scan for lingering hotspots, which, if not extinguished, can reignite fires and hamper recovery efforts.
Whereas video cameras see reflected light in the visible part of the electromagnetic spectrum, thermal imagers are able to see the infrared band, invisible to the human eye. It’s like being able to see the radio waves from your wi-fi hub.
Thermal imagers can clearly illuminate not only flames and hot gases, but people whom responders would otherwise never see in smoke-filled buildings. They then display those images vividly on small hand-held devices or, more recently, on tiny screens built into firefighters' breathing masks.
A Hot Item
Thermal imaging cameras have been a growing part of firefighters' gear package for years. Departments have been snapping them up at a record pace. An assessment by the National Fire Protection Association showed the percentage of fire departments equipped with the technology rose from 24 percent in 2001 to nearly 80 percent this year.
Over those years, the gadgets more than proved their worth. The logical next step was to make them airborne. Enter the age of the drone.
"It's an absolute game changer for us," says Tom Calvert, a battalion chief with the Menlo Park Fire Protection District. The district is rapidly expanding its drone program because of the edge Calvert says it gives responders to have a UAV in the sky above an incident.
"You can pinpoint over a larger area," he says, "hot spot there, hot spot there — and direct your resources right where they need to go."
Eyes in the Sky
Commander Tom Madigan, who heads the Alameda County Sheriff's drone operation, says the Oakland Ghost Ship fire was the fourth time they've deployed on a fire incident. As Madigan's team flew the drone, an Oakland Fire representative viewed color-coded images on the screen and directed ladder crews where to concentrate their water from overhead.
The Oakland warehouse fire moved very rapidly through the building, putting firefighters on the defensive despite an estimated three-minute response time. Calvert says fast-moving fires have become the norm, in large part because of the plastic and other synthetic materials inside.
"The fuels inside of buildings are different than they used to be 30-40 years ago, when they were cottons and wood fibers and you know, all the natural materials," explains Calvert. "Now it’s petroleum. It’s like gasoline. The fires burn a lot faster now.
So we’ve lost a bit of time, you know, in our battle against time."
Drones could help offset that. Calvert and other experts interviewed for this story say it won’t be long — perhaps a couple of years — before video and thermal camera-equipped drones will automatically take off from fire stations as soon as alarms come in, racing ahead of the engines and paramedics to send back initial data that could save time and lives. Drones could virtually eliminate the ground-level "360," a time-consuming site evaluation that responders currently do as they arrive on scene.
"Before we even get there, we can get very good information about this incident," says Calvert, "and that helps drive where we put people and what we have them do."
Calvert calls thermal imaging and drones two of the four great breakthroughs in modern firefighting, right up there with breathing apparatus and radios. While figures are hard to come by, drones with thermal imaging cameras are rapidly becoming standard equipment for fire companies.
"It's really been picking up," says Romero Durscher, director of education for DJI, a leading maker of drones used by public safety agencies, including the one used in Oakland. "We're seeing more and more first-responder agencies using the technology and there's a whole lot more that are just waiting and trying to figure out best practices."
Those "best practices" are important. As drones become more ubiquitous, they’ve stoked public anxiety over privacy and safety.
"Every time we've had a major new technology come about, there were always concerns," says Durscher.
"We truly believe this technology can have a very positive impact."
"You're going to see an explosion of [this] technology used by public safety agencies," predicts Madigan, whose unit also deploys drones in search-and-rescue and "high-risk" situations such as active-shooter incidents. Calvert agrees.
"I think as you see more actual emergency response-type incidents where you see the drone in use and the benefit it gets us," he says, "it’s hard to argue its value, certainly in emergency response."
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