Rio Rico firefighters test brand new tool to stop electric vehicle fires

RIO RICO, Ariz. (KGUN) -- — For firefighters in Santa Cruz county, the future of transportation is here. In the next 10 years more drivers will cruise down the road in electric cars, trucks and SUVs.

However, the older tools crews use are not guaranteed to put out a fire that starts when an EV's battery explodes.

That's why Rio Rico Medical and Fire District jumped at the chance to be the first department in all of Arizona to test a new tool. In theory, it helps crews save both precious time and water.

KGUN9 joined firefighters trying out the box for the very first time on Tuesday.
But, before Rio Rico Fire crews could get their hands on it, they sat down for a PowerPoint slideshow.

RRMFD used $35,000 in state grant money to buy what Rosenbauer manufacturing calls its battery extinguishing system technology, or BEST.

"We already have electric fire trucks, electric semis, we have all this stuff," RRMFD senior adviser Frank Granados said. "It's here. We're just trying to get ready for it and trying to prepare for it when it does happen."

In the hot summer sun, Granados stood back and watched crews follow Rosenbauer instructor Zach Paul's directions.

The firefighters connected the BEST box to their truck, attached the corresponding hoses, and rolled BEST under a car.

Using air pressure, a steel tip pierced the test car's floor, to get to the simulated heart of an EV battery pack.

"With new tools, it's going to come with some growing pains," Granados said. "We know that, but it's better to have this tool and be able to utilize it than to not have it."

Firefighters looked inside the simulation car after using the BEST box. It was not an EV, but RRMFD said they wanted to get a handle on what this system can do. Crews want to hear the pop of the steel tip coming through the car's bottom so it can spray around 8-10 gallons a minute for as long as they need.

"I worked in the big city for 30 years, had tons of water. Every 100 feet, I had a fire hydrant," Granados said. "Out here, water is a precious resource not just for hydration, but for suppressing fires."

Granados and RRMFD stressed their priority is not to put an EV battery fire completely out. Their approach will change depending on if it's a full EV or hybrid vehicle.

What matters most, they said, is getting the temperature down inside the battery pack. Water from the BEST box will help stop what's called a thermal runaway inside the pack.
After that, crews said then they can focus on covering the rest of the flames burning the car's cabin and exterior.

Granados said depending on whether a driver in an emergency has a full EV or hybrid, their call from a safe place will help firefighters plan their mission.

"(Give us) as much information as they can give us, prior to our arrival with electric vehicles, as to what type of vehicle it is," Granados said. "Our firefighters can now get on their phones and start searching, scanning to see where those points are."

Rio Rico crews said they know they'll run into new risks with EV battery smoke and leaks. The cars can emit dangerous chemicals like hydrogen fluoride.

Because of that, Granados said crews will train to still use a handline to keep the flames at bay. They will also fine-tune their approach to controlling any contaminated water that flows out from the car.