FSRI Completes Initial Experiments Investigating the Impact of Vehicle Fires on Personal Protective Equipment
The Fire Safety Research Institute (FSRI), part of UL Research Institutes, recently completed experiments for the first two phases of the Emerging Issues Related to Personal Protective Equipment (PPE) project. This project explores how firefighter PPE performs amid an ever-evolving fire environment. The first two phases focus on exposing turnout gear swatches to electric vehicle (EV) and internal combustion engine (ICE) (i.e., gas-powered) vehicle fires.
EVs pose unique risks to firefighters, in part because when an EV battery burns, it can release particulate and gaseous contaminants such as heavy metals, acid gases, volatile organic compounds, and other hazardous chemicals that can contaminate firefighters’ gear. The level of toxicity from EV fires is not fully understood. By comparing how contaminants from each type of fire impact PPE, the fire service can better understand and evaluate the risks that EV fires pose.
PPE Test Setup Designed to Mimic Firefighting Positions in Vehicle Fires
Researchers designed an experimental setup to examine thermal and chemical conditions during vehicle fires. They measured the temperatures, thermal energy, and gas and particulate emissions from the fires by using heat flux panels, infrared cameras, temperature sensors, and both active and passive air sampling equipment. In addition, swatches made from the three layers of firefighters personal protective equipment (PPE) were positioned around the vehicle.
Experimental setup, showing the vehicle (center), heat flux panels (sides of vehicle), infrared camera (front left), 10 ft. PPE sampling location (front right), plume curtain (top), and plume sampling location (top, gray box).
Experiments were divided into two groups: burnout tests and suppression tests. For each test, researchers positioned PPE swatches at three key locations. In the burnout test, the first two locations were at operating level located at 10 feet and 15 feet from the vehicle—tactical distances where a firefighter might stand to conduct suppression. The third position was above the vehicle directly in the plume, next to the curtain.
For suppression tests, swatches were again placed 15 feet from the vehicle and above the vehicle. The third position in these tests involved attaching swatches directly to the turnout gear of firefighters actively engaged in vehicle fire suppression. Researchers secured swatches on the forearm, to capture potential exposure when reaching under or into a vehicle; on the leg, to measure exposure with less direct contact; and on the chest. The swatches stayed in position from vehicle ignition through suppression. To date, researchers have used this experimental setup in a total of 13 vehicle fires, including burnout tests for three ICE vehicles and six EVs, and four EV suppression tests.
Preparing for the Final Phases of PPE Experiments
The next phases of this project include completing the analysis of the chemical contamination of the PPE swatches and evaluating the effectiveness of laundering techniques. PPE swatch analysis is currently underway to assess the concentrations of heavy metals and polycyclic aromatic hydrocarbons (PAHs)—hazardous chemicals created when organic material is burned. Researchers will also investigate laundering techniques by using a small-scale extractor (i.e., a benchtop washing machine) to compare how well traditional laundering techniques and liquid CO₂ cleaning remove heavy metals and PAHs from PPE.
“This project gives us the unique opportunity to see how today’s evolving fire environment impacts the gear that protects us. We’re committed to fully characterizing these fires and translating the findings into practical insights for the fire service. This will help us contribute to better practices and cleaning techniques related to our personal protective equipment.”
—Richard Kesler, research engineer, FSRI
The progress made in these experiments is critical for a deeper understanding of PPE performance in modern fire incidents, like EV fires. Researchers will publish a detailed analysis of the results in upcoming peer-reviewed publications.
