Chassis Components, Engine Company, Haddon

Today’s New Vehicle Car Fires

Issue 8 and Volume 23.

Carl j. Haddon

Over the years, we’ve learned, or certainly should have learned, how new vehicle construction has changed and how many of our tried and true old-school methods, tactics, and tools for vehicle extrication are now considered antiquated and downright dangerous for patients and rescuers alike.

Carl j. Haddon

Likewise, we’ve learned how residential building construction has changed (as well as how furniture construction and room content materials have changed) and, as a result, we have had to severely alter how we think about some of the decisions we make concerning fire attack. This has also affected some of the firefighting equipment, personal protective gear, and apparatus that we use as well as our game plan.

What about new vehicle fires? We understand that new vehicles are made differently, and they are made with lots of high-strength steel that makes extrication more of a challenge. Are you aware of and educated about what the combustibles found in new vehicles consist of? Do you know if today’s new vehicle fires are Class A, B, C, or D? And, most importantly, do you know what tools, equipment, personal protective equipment, apparatus, and firefighting agents you should use (and those you should not use) to fight these fires?

I recently asked a “salty” colleague of mine, who readily proclaimed to me that “all vehicle fires are Class A fires.” Are they really Class A? If so, conventional wisdom tells us that the use of water, dry chemical powders, and firefighting foam should extinguish them, right? But, today’s new vehicles are filled with magnesium, titanium, aluminum, and lithium ion batteries that are highly combustible. Do you still want to throw water at them with these Class D components?

1 The result of a fire involving a new high-strength aluminum body truck. (Photos by author.)

2 Thermal runaway causes a lithium ion car battery to erupt, resembling a cross between a jet engine and a volcano.

3 Electric and hybrid car fires pose many new hazards to firefighters.

1 The result of a fire involving a new high-strength aluminum body truck. (Photos by author.) 2 Thermal runaway causes a lithium ion car battery to erupt, resembling a cross between a jet engine and a volcano. 3 Electric and hybrid car fires pose many new hazards to firefighters.

If you have never seen a lithium ion (hybrid/full electric) vehicle battery fire, you are in for a treat and a nightmare all rolled into one. When these batteries catch fire because of thermal runaway, they look and sound like a cross between a volcano and a small jet engine. They reach tremendous temperatures and spew molten copper and aluminum (that will destroy turnout gear). These batteries typically burn in multiple bursts as the individual battery cells ignite and burn. They are regularly responsible for large multiple secondary flash fires from ignition of the gases that they emit. In many vehicles, these large lithium ion battery packs are located underneath and behind the rear passenger seats. To protect these batteries from damage on impact, some models (i.e., the later generation of Chevy Volt) have these batteries encased in ultra-high-strength-steel battery boxes, making them virtually impossible to access with a hoseline.

These batteries don’t burn independently of the rest of the vehicle. They quickly spread the fire and intense heat to the other parts of the vehicle, which easily ignite the large quantity of magnesium components found throughout the passenger compartment, dash/cowling area, steering components, and engine compartment. Do you still want to throw water at this “Class A” fire?

European studies show that if water alone can even be successful on these battery fires, it takes an estimated 3,000 gallons. Do you bring/dispatch 3,000 gallons of water to a vehicle fire? How long might it take you to get 3,000 gallons to a fully involved vehicle fire on a congested freeway? At this point in the (Class D) conversation, conventional firefighting foams and water are ineffective, contraindicated, and dangerous to use on these vehicle fires.

When I teach, students want to talk about hybrid and electric high-voltage shock hazard issues. When you pull up on a vehicle fire, do you know if the high-voltage power supply has been shut down before you open up on it? If not, do you have any concern about the high-voltage power feeding back through your hose stream to the brass nozzle you’re holding with wet gloves? Just checking: Class A … or Class C?

Let’s take this hybrid/electric lithium ion car battery fire scenario to the next level. In many of today’s hybrids, there exists a combination of electric and naturally aspirated gasoline-powered motor/engines. In many models, these battery packs are located behind or under the back seat. Directly behind the lithium ion battery pack box lies a gasoline tank that fuels the gasoline engine. When this fuel tank ruptures, or should the accident involve a big rig or another vehicle with substantial amounts of hydrocarbon-based fuel (gas or diesel) that is leaking, burning, and flowing (three-dimensional flowing fuel fire), do we still have a Class A fire situation? It sounds a lot to me like a 3D Class B fire. Both water and foam [National Fire Protection Association (NFPA) 11, Standard for Low-, Medium-, and High-Expansion Foam] are contraindicated on flowing 3D Class B fires, so now what are we going to do?

4 Putting the wrong firefighting agent on a lithium ion battery and combustible metal car fire can have disastrous and explosive results.

4 Putting the wrong firefighting agent on a lithium ion battery and combustible metal car fire can have disastrous and explosive results.

Some of you may think that this scenario sounds like a never-ending Hollywood disaster movie, but this exact type of fire incident has become an everyday reality for departments around the world. So, are today’s new vehicle fires to be treated as Class A, Class B, Class C, or Class D metal fires? My point is, don’t narrow your view. Plan, train, and be prepared for the worst and hope for the best. There’s not much worse than attacking a vehicle fire as a Class A fire with water or foam and unexpectedly encountering a batch of burning magnesium that’s competing with a burning lithium ion battery for the best fireworks show.

This is not a rural vs. urban or career vs. volunteer issue. These vehicles are on all our roads, highways, and freeways—right now, every day. Are you as educated about the hazards of new fire dangers as you are on new building construction? Do you presently employ or have access to firefighting agents that can be used on metal and 3D Class B fires? Have you trained on how to access and extinguish lithium ion battery fueled car fires? If you answer no, you’re not alone. Most departments are unprepared until they encounter it! This is simply more technology that we must stay on top of. These are big issues, and fortunately there are new technology firefighting solutions available to us.

I am a big proponent of the water additive (not wetting agent) encapsulator technology (NFPA 18A, Standard on Water Additives for Fire Control and Vapor Mitigation, 7.7). True encapsulator agents (in simple solutions of one to three percent, depending on the brand) make very short work of these new vehicle fires and all the Class A, B, 3D B, and D components. I intentionally leave out the Class C electrical component because even though studies show that true encapsulator solution is very effective, I can’t condone opening up on an electrically charged fire source of any kind.

Only you know if your department is prepared with the information, training, and solutions for these new car fires. In the meantime, do your homework. Educate yourself, your crews, and your bosses about the changes in vehicle construction, components, new vehicle fires, needed equipment, and new technology. It’s all about “sharing knowledge forward.”


CARL J. HADDON is a member of the Fire Apparatus & Emergency Equipment Editorial Advisory Board and the director of Five Star Fire Training LLC, which is sponsored, in part, by Volvo North America. He served as assistant chief and fire commissioner for the North Fork (ID) Fire Department and is a career veteran of more than 25 years in the fire and EMS services in southern California. He is a certified Level 2 fire instructor and an ISFSI member and teaches Five Star Auto Extrication and NFPA 610 classes across the country.