UL burns 18 EVs to develop guidelines for firefighters

UL Research Institutes’ Fire Safety Research Institute has released a new report on EV fires and suppression tactics, called “Full-Scale Electric Vehicle Fire Experiments and Recommendations for Fire Incident Response.”

ULRI conducted full-scale burns of 18 vehicles (what fun!) to examine the differences and similarities between gas-vehicle and EV fires. This included 9 free burns, or experiments conducted without fire suppression. Following the free-burn experiments, the research team burned 9 additional EVs to evaluate common suppression tactics, including water only, EV fire blankets, and water with an added suppression agent. Researchers fully charged the EVs, initiated the battery fires with a propane burner, then allowed the fires to grow for six minutes before beginning suppression. The six-minute delay replicates standard fire response time in North America.

Key findings from the report include:

• Data from free-burn experiments indicated that EV and ICE vehicle fires are similar in fire growth rate, peak fire size and fire duration.
• For most EV fire incidents, water can be used to suppress the cabin fire, limit exposures and control flaming from thermal runaway while the battery burns itself out. None of the tested suppression techniques halted thermal runaway once it started, and an added suppression agent was no more effective than water.
• EV fire blankets should be used with caution. While effective for controlling vehicle flaming, researchers observed that an explosion hazard can occur when flammable gases accumulate underneath a deployed EV fire blanket. Blankets should not be considered a replacement for water-based suppression.
• Full personal protective equipment and self-contained breathing apparatus are required throughout any EV fire incident.

The full report provides detailed considerations for firefighters. The team also developed an EV Fire Tactical Decision Aid, a step-by-step tool designed to analyze, develop and improve fireground decision-making.

“This research moves us closer to understanding how batteries change the fire environment and helps equip first responders to adequately address fires involving this new source of fuel,” said Adam Barowy, Principal Research Engineer for the Fire Safety Research Institute. “Our findings demonstrate that when it comes to EVs, first responders can effectively manage the hazard with familiar tools and tactics.”

Source: UL Research Institutes