Rob Rupert, a certified safety professional and wildland and structural firefighter, told attendees that lithium-based batteries in phones, scooters, laptops and electric vehicles pose unique fire hazards and that many common extinguishing agents are ineffective or can worsen certain battery fires.

Rupert described thermal runaway — a process where a damaged or overheated lithium cell rapidly fails and can re-ignite hours or days after initial suppression — and cited local incidents including a multi-million-dollar fire loss from an electric scooter charged in low temperatures. He said some lithium chemistries such as lithium iron phosphate (LFP/LiFePO4) are less prone to rapid failure, but still carry risk.

On extinguishers, Rupert outlined the standard fire classifications and how agents work: Class A (ordinary combustibles), B (flammable liquids), C (energized electrical hazards), D (combustible metals) and K (cooking oils). He said that dry-chemical ABC extinguishers are common and universal for quick knockdown, but can be corrosive to electronics and are a single-use discharge; dry powder may not fully extinguish lithium-battery fires and can allow re-ignition. He said some clean agents (halon replacements) are effective but are tightly regulated for environmental reasons.

Rupert warned homeowners about an industry recall: many small plastic-headed consumer extinguishers made by Kidde were recalled because of head failures; owners can claim a free replacement metal-headed unit from the manufacturer’s recall process. He urged people to check serial numbers and manufacturing dates and to replace or service extinguishers that show failed pressure indicators.

For lithium-battery incidents he recommended the following practical steps: remove a hot or smoking device from enclosed spaces and place it outdoors in a metal container away from combustibles, do not rely on water or dry chemical alone to fully extinguish a lithium-battery thermal-runaway event, and be prepared for re-ignition (some EV wrecks and crushed battery incidents have relit days later). He also discussed foam sticks and class-A foam in-line devices that increase water effectiveness for vegetation and Class-A fuels but cautioned that they are not a cure-all for battery fires.

Rupert addressed charging habits and consumer electronics: most UL-marked consumer products are robust, but cheap uncertified batteries and off-brand chargers increase risk. He recommended keeping chargers and devices in ventilated areas, not charging devices in sub-zero conditions without proper battery-management safeguards, and using N95 masks or escape respirators during smoke exposure.

He also covered extinguisher maintenance and selection: pressure-gauged metal-headed extinguishers or rechargeable pressurized-water cans can be practical for homesteads; look for units with refillable air chucks and follow hydrostatic test requirements. He concluded that awareness of battery chemistry, safe charging and proper extinguisher selection and maintenance are essential parts of home fire safety.