LIO RICO, Arizona (KGUN) — The future of transportation is here for Santa Cruz County firefighters. Over the next decade, more drivers will hit the road in electric cars, trucks and SUVs.

However, the old tools used by crews are not guaranteed to be able to extinguish fires that occur when an EV’s battery explodes.

That’s why the Rio Rico Medical Fire District jumped at the chance to be the first department to test the new tool across Arizona. In theory, it helps the crew save precious time and water.

KGUN9 joined firefighters in testing the box for the first time on Tuesday.
But before the Rio Rico Fire crew actually got to work, they sat down to watch a PowerPoint slideshow.

RRMFD used a state grant of $35,000 to purchase what Rosenbauer Manufacturing calls their Battery Fire Extinguishing System Technology (BEST).

“We already have electric fire trucks, electric semi-computers and everything,” said RRMFD Senior Advisor Frank Granados. “It’s here. We’re just trying to be prepared for it and be prepared when it happens.”

In the hot summer sun, Granados stood back and watched the crew follow the instructions of Instructor Zach Paul Rosenbauer.

Firefighters connected the BEST box to the truck, attached the corresponding hoses and rolled the BEST under the car.

Using air pressure, a steel tip penetrated the floor of the test car and reached the simulated heart of the EV battery pack.

“There will be some growing pains with the new tools,” Granados said. “I know that, but it’s better to have this tool and be able to use it than not to have it.”

Firefighters looked inside the simulation car after using the BEST box. It wasn’t an EV, but RRMFD said they wanted to figure out what the system could do. Crew members want to hear the sound of steel tips popping from the bottom of the car so they can spray 8 to 10 gallons per minute as much as they want.

“I worked in a big city for 30 years and there was a lot of water. There was a hydrant every 100 feet,” Granados said. “Here, water is a valuable resource not only for hydration, but also for fire suppression.”

Granados and RRMFD emphasized that completely extinguishing EV battery fires is not a priority. The approach changes depending on whether it is a full EV or a hybrid vehicle.

The most important thing is to reduce the temperature inside the battery pack. Water from the BEST box helps prevent so-called thermal runaway inside the pack.
Crew members said they could then focus on covering the remaining flames burning the car’s cabin and exterior.

Granados said the call from a safe location helps firefighters plan their missions, depending on whether the emergency driver owns a full EV or a hybrid vehicle.

“Before you arrive with an electric vehicle, please give us as much information as possible about what kind of vehicle it is,” Granados said. “Firefighters in our country can now use their mobile phones to initiate searches and scans to see where the scene is located.”

The Rio Rico crew said they knew they faced new risks from EV battery smoke and leaks. Cars can emit dangerous chemicals such as hydrogen fluoride.

As such, Granados said crew members will continue to be trained to use handlines to prevent flames. It will also tweak its approach to managing polluted water runoff from cars.