Fire staff warn of electric-vehicle hazards in parking garages; NFPA changes could raise sprinkler needs

During the April meeting, district staff warned that electric-vehicle (EV) fires present heightened challenges for parking structures, especially podium-style construction with parking below residential units.

Assistant Chief Nearings explained that EV batteries can experience thermal runaway when a single cell fails, a process that can cascade through battery modules and produce much higher temperatures than conventional internal-combustion-engine fires. "It puts out a significant violent reaction," Nearings said, and staff cited several large parking-structure fires in Europe to illustrate structural risk and the potential for extensive water use.

Staff described two code-related pressures: the 2022 NFPA updates reclassified many parking garages from "ordinary hazard 1" to "ordinary hazard 2," which increases sprinkler demand roughly 30% (from 0.15 to 0.2 gallons per minute per square foot in the presenter's example). The district noted the state has not yet adopted the 2022 NFPA edition; staff discussed the option of adopting targeted local amendments for parking structures before state adoption, subject to legal guidance.

Board members asked whether retrofits would be required for existing structures (staff said no retroactive blanket retrofit is planned, but permits for new construction could be adjusted and staff discussed verifying hydraulic capacity before allowing charging-station installations in older garages). Staff also flagged broader mitigation tools: designated EV parking, increased pipe sizing and heads, ventilation control, and the ability to terminate power to charging systems.

No ordinance was adopted at the meeting. Staff said they are consulting legal counsel and ICC professionals and will return with draft language and technical guidance for the board to consider.