"The e-cigarette had a catastrophic failure," Schofield said. "… The batteries overcharged and the batteries failed and expelled the coils at the end of the tube."
The boy suffered first- and second-degree burns, which, though relatively minor, are painful, Schofield said.
The fire marshal said that this is the second time he has investigated an e-cigarette fire. In the other case, a charging e-cigarette shot out its coils into a laundry basket, burning the laundry but causing no injuries, he said.
Schofield, who has heard similar stories from fire marshals around the country, alerted the Food and Drug Administration, which regulates e-cigarettes. He received notification Monday afternoon that the FDA received his report.
The driver had been charging the e-cigarette with the charger that came with the product, though Schofield has heard the device failure also happens with after-market chargers.
"It's a fairly new product so our data on device failure is pretty limited," Schofield said. "…This is not a device that I would plug into my wall and leave unattended. We were fortunate, the [boy's] burns were relatively minor, but it was certainly a wake up call."