By Tatum Todd
oregonlive.com
PORTLAND, Ore. — Multiple lithium-ion batteries exploded in Portland State University’s Engineering Building Tuesday morning, forcing more than 100 students and staff to evacuate the building for about two hours.
The incident is the latest of several lithium-ion battery explosions in the Portland area in in the last year, including two separate apartment fires in September 2024 that burned multiple people out of their homes, a smoldering tablet on a flight that landed at PDX that same month, and an another apartment building fire last August sparked by an e-scooter battery explosion.
Nobody was injured in the PSU explosions on Tuesday, and the Engineering Building, on Southwest Fourth Avenue, has reopened – with the exception of the fourth floor, where the explosion happened, fire and PSU officials said.
Nearly two dozen firefighters responded to the scene around 10:30 a.m. to find a fourth-floor classroom filled with toxic smoke, Portland Fire & Rescue spokesperson Rick Graves told The Oregonian /OregonLive.
Graves said students were using the batteries to power devices for a class project when the first battery exploded — but everyone apparently believed it was an isolated incident and carried on with their work, Graves said.
But soon the remaining batteries also exploded — and the students and staff found themselves in an emergency situation, Graves said.
Portland fire evacuated the building, and fire crews entered wearing air tanks and breathing masks to protect themselves from the toxic fumes.
The crews quickly sealed the batteries in lidded “disposal buckets,” and the smoke was contained within the small windowless room where the batteries exploded, Graves said. Firefighters were then able to vent the fumes out of the room using the building’s HVAC system.
“Portland State’s Environmental Health and Safety staff are conducting air-quality monitoring,” PSU spokesperson Katy Swordfisk said in an email. “No classes will be impacted at this time.”
The smoke in this case was contained and flushed out, Graves said, but he warned people about the dangers of inhaling fumes from lithium-ion batteries that have exploded.
“The smoke from (battery fires) contains significant toxins that can be a respiratory irritant that can cause respiratory distress, and possibly respiratory arrest at times,” Graves said, adding that the fumes can contain hydrogen fluoride, sulfuric acid, nitric acid and benzene. “It’s pretty significant, and it’s a growing concern in the fire service.”
Lithium-ion batteries — which are found in a range of everyday devices, such as laptops, phones, tablets and portable power banks — can explode when they heat up too much, the result of what’s known as a “thermal runaway reaction.” Such reactions are relatively rare, but anyone who feels a battery growing excessively hot to the touch should submerge it in water to stop a potential thermal runaway from escalating, Graves said.
Submerged batteries should stay underwater for up to 48 hours before being taken to a battery-disposal center, he added.
“There have been reports of fires,” Graves said, “where these batteries have ignited, been extinguished and then reignited 24 hours later.”
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