Due to the nature and potential duration of a fire involving an electric vehicle, the second due company, whether it be a rescue or squad company play a vital role in the strategies and tactics of fire suppression operations.

Here are a few considerations for second due companies in response to an electric car fire.

Upon arrival and not completed, establish a delineated Hot Zone and ensure all personnel are in full PPE and donned with their SCBA and on air.
Consider ventilation. The buildup of vapors from an EV are potentially toxic, flammable and explosive. If deemed safe, the second due engine should consider and attempt to open two doors of the vehicle to allow and prevent buildup of vapors.
Attempt to shut down the high voltage system of the EV, if it is not already on fire.

Provide access for the suppression team to the location of the battery in order for water to be applied directly on it. This will help cool the battery and prevent thermal runaway.
Ways to open the vehicle for access to the battery depending its location

Remove the doors and rear seat top
Open and remove the trunk lid
Tilt the vehicle for access to the floor batteries. Consider using air bags, spreaders and cribbing, a comealong or winch to do so.

The main purpose of the second due company for electric vehicle fires is to provide safety for all personnel on scene and work in obtaining access to the EV battery location to help prevent further thermal runaway. Since cooling these batteries could take up to 30 minutes or more, it is vital there is a dedicated company on scene working to identifying and gaining access to this crucial piece of the vehicle.

Key Terms

High Voltage

For automotive applications, any voltage greater than 30 volts alternating current, or AC, or 60 volts direct current, or DC, is considered to be a high or hazardous voltage due to the potential to produce serious injury or death due to electric shock. Electric drive systems on commercial vehicles can operate at voltages as high as 800 volts, both AC and DC, and can produce peak currents as high as 100 amps, which make contact with high voltage components even more dangerous.

High Voltage Cables

Visible orange cables are another indication that a vehicle has a high voltage system. That is because there is a voluntary Society of Automotive Engineers, or SAE, recommended practice that specifies that all high voltage cables have an orange outer covering. While voluntary, this practice has been adopted by virtually all manufacturers.

Until next time, work hard, stay safe & live inspired.

Automotive technological advancements have evolved drastically over the years. Modern amenities of connectivity are found is every new car being brought onto the market today. Social media apps, real time traffic and weather updates to cameras not just for backing up but also for covering multiple blind spot areas of the car. Although the biggest advancement and great challenge for firefighters is in the invention of electric vehicles (EV).

Firefighters must be aware of the dangers of these vehicles and have steps in place when responding to vehicle fires involving electric vehicles. For purposes of this article, we are going to outline steps to take when responding to an electric vehicle fire as the first arriving engine company.

Secure a Water Supply

As any well-trained engine company, the first thing that must happen is to secure a water supply immediately upon arrival. This is a crucial step in a meaningful knock on the fire. When compared to an internal combustion vehicle (gas fueled), an electric vehicle can take up to ten times the amount of water to cool or extinguish.

Let's think about this. An internal combustion vehicle would normally take 500-1000 gallons of water to cool or extinguish while an EV would take a minimum of 10,0000 gallons of water alone to extinguish or cool the battery. Reports have shown that it has taken 30,000 - 40,000 gallons of water to do such fire suppression on EVs.

Up to 150 000 liters of water needed to put out a fire in an electric car | CTIF - International Association of Fire Services for Safer Citizens through Skilled Firefighters

Once a water supply is established, the next best option is to treat this like a motor vehicle extrication and if possible, stabilize the car and initiate any victim removes if required. The silent movement of these vehicles could cause them to roll and cause for other hazards putting firefighters at higher risks of injuries from the moving vehicle.

Handline Selection

Due to the naturae of these vehicles and the amount of water needed to either cool or extinguish the fire, it is best to either stretch a 2 1/2-inch handline or if staffing permits, pull multiple 1 3/4-inch handlines. As suppression team(s) approach the vehicle, it is important to utilize the reach of the straight stream of the nozzle and to take note of the reaction the vehicle is having with the water. The initial application of water may cause a flare up of fire due to the combustibles within the EV.

Locate the Battery

Upon extinguishment of the main body of fire, it is imperative that firefighters quickly locate and identify the location of the battery, and this is important for monitoring signs of thermal runaway using a thermal imaging camera (TIC), including:

Identify the heat signature present
Vapors escaping from the battery pack
Listen for popping sounds from the battery pack
Locating visible fire around the battery pack

*Note, the thermal runaway temperature for lithium-ion batteries is approximately 176 degrees Fahrenheit or 80 degrees Celsius. Beyond this, the risk of chemical reactions leading to thermal runaway increases drastically. The maximum temperature during thermal runaway can reach greater than 300 degrees Celsius or 572 degrees Fahrenheit.

If any of these signs are identified, the battery pack should begin to be cooled and performed in such manner:

The stream from the hose line should be directed to one area on the battery pack and applied for 3 to 5 minutes
After the 3 to 5 minutes, firefighters should assess the battery again for thermal runaway and the items listed above.
Should the signs of thermal runaway still be presentable or have seemed to be found on a new area of the battery, the stream should be again applied for another 3 to 5 minutes, followed by another assessment of the battery pack.
This process should be repeated until the pack is no longer showing any elevated temperatures.

Monitor the Battery

After fire suppression team(s) have cooled the or extinguished the battery and all hot spots on the battery have cooled, it is best for an engine company to remain in place with an established water supply still in place for at least 30 minutes before the EV is moved from the hot zone.

Key definitions to take note of:

Thermal Runaway

Thermal runaway occurs when a lithium-ion battery becomes overheated and is often triggered by overcharging, a short circuit or other cell stress. A chain reaction in the cell that generates gas is triggered by excess heat. This can spread to the rest of the battery pack if not mitigated, which can cause other cells to overheat and then decompose. The runaway causes the release of flammable gasses as it takes hold and the battery cells break down.

Lithium-ion Battery

A lithium-ion (Li-ion) battery is an advanced battery technology that uses lithium ions as a key component of its electrochemistry. During a discharge cycle, lithium atoms in the anode are ionized and separated from their electrons. The lithium-ions move from the anode and pass through the electrolyte until they reach the cathode, where they recombine with their electrons and electrically neutralize.

As the fire service studies and investigates the complexity of electric vehicles fires, it is imperative that we continue to remain diligent when responding to EV fires and keeping up with the everlasting changes of how to approach and attack fires involving electric vehicles.

Until next time - work hard, stay safe & live inspired.

EV Rescue

https://autorescueapp.com/index.html

NFPA

https://www.nfpa.org/education-and-research/emergency-response/emergency-response-guides#aq=%40culture%3D%22en%22&cq=%40taglistingpage%3D%3D(%22EV%20Guides%22)%20%20&numberOfResults=12&sortCriteria=%40title%20ascending

Electric Vehicle Fire Considerations for Second Due Company Response

Electric Vehicle Fire Considerations for the First Due Engine Company