Thermal Imager Use at MVIs

Today’s challenges for the fire service are getting more complex when responding to a motor vehicle incident, says Manfred Kihn.
Today’s challenges for the fire service are getting more and more complex when responding to a motor vehicle incident (MVI), regardless of if it involves a single vehicle on a back road, a multivehicle accident, or a major pileup on a freeway or an interstate.

Vehicles in travel are usually powered by gasoline or diesel, but with “green technology” becoming more and more popular, people are gravitating toward hybrid and electric-powered vehicles. Different types of vehicles call for different thermal imager (TI) tips and tricks. In this article, I will break down differences in vehicle types and how your TI can help you navigate through MVIs.

Hybrid and Electric Vehicles

Hybrid electric vehicles are powered by an internal combustion engine and an electric motor, which uses energy stored in batteries. An example of this is the Toyota Prius. A hybrid electric vehicle cannot be plugged in to charge the battery. Instead, the battery is charged through regenerative braking by the internal combustion engine.

Electric cars function by plugging into a charge point and taking electricity from the grid. They store the electricity in rechargeable batteries that power an electric motor, which turn the wheels. Electric cars accelerate faster than vehicles with traditional fuel engines, so they feel lighter to drive (popularly seen in Tesla models).

When arriving on scene to calls in darkness, on a back road, or involving multivehicle pileups, do we really pay attention to what types of vehicles are in involved? Usually not, as we are focused on the situation at hand and prioritize what needs to be done, such as patient care and extrication. This where the use of a TI can aid first responders arriving on scene to help gather information regarding any potential hazards.

Before approaching any vehicle, you should conduct a 360° scene survey using your TI and look for hazards such as fuel leaks, down utility/power lines, and so on. At the same time, determine what type of vehicle is in the accident, especially if patient extrication is required. If the vehicle is a hybrid or electric model, it can have different battery placement and type compared to a standard vehicle. The battery can be in the undercarriage and run the length between the front and rear wheels, which is important to know when cutting into a vehicle to save a life. Damaged or heavily overheated lithium-ion batteries in electric vehicles can transit into a thermal runaway reaction with further heat and gas release. The heat may cause a battery fire and a fast gas release may damage the battery pack casing. This type of heat will certainly be visible; using your TI can help determine your course of action.

 A power utility line hazard on the roof of a vehicle. (Photos courtesy of Bullard.)

 A fuel drum hazard lying next to a vehicle at an incident.

Semi Trucks

Another challenge for the fire service is the response to semi truck incidents involving commodities transportation such as Home Depot or Lowe’s. These trucks carry everything from garden fertilizers and chemicals to household cleaning products, paints, and thinners. Encountering these during an incident will keep your fire department’s hazmat team busy.

Conducting a 360° size-up with a TI is vital, but there are three main priorities:

  • Patient care and extrication—again, only if the vehicle is approachable and there are no harmful hazards for the first responders. If there are, those must be mitigated for safety reasons.
  • Check the stability of the side saddle diesel fuel tanks, using your TI for any spills or leakage. Remember that diesel fuel is lighter than water, even though the molecular weight is greater. Water has a higher density than diesel; therefore, diesel floats on water. This can be detected using a TI. This is important to note if there is water around the incident area.
  • Carefully examine the exterior walls of the truck’s trailer for any potential heat signatures, similar to what you find when conducting a 360° size-up at a typical structure fire. Keep in mind that if the trailer displays a shiny/glossy surface, you will pick up reflections while using your TI. Changing your angle of view will help eliminate that limitation. Report any detected heat signature to the hazmat team to make them aware of any potential interior hazards.

Using a TI at a motor vehicle incident is not going to solve all your problems, but it is another tool for when you have diminished vision in nighttime or limited-visibility conditions. Think about that the next time you roll in on the scene to an MVI and the TI is sitting in the charger next to you. Grab it and bring it with you. It can’t hurt!

Manfred Kihn is a 19-year veteran of the fire service, having served as an ambulance officer, emergency services specialist, firefighter, captain, and fire chief. He has been a member of Bullard’s Emergency Responder team since 2005 and is the company’s fire training specialist for thermal imaging technology. He is certified through the Law Enforcement Thermographers’ Association (LETA) as a thermal imaging instructor and is a recipient of the Ontario Medal for Firefighters Bravery. If you have questions about thermal imaging, you can e-mail him at

No posts to display