Electronic cigarettes may be safer for the lungs of smokers than the standard leaf-burning variety, some people believe, but Medford fire officials want people to know they can still cause fires.
E-cigs have caused minor fires at two Medford homes recently, Medford Fire-Rescue officials said.
Fire Marshal Greg Kleinberg said the lithium batteries used to power the nicotine vaporizers can explode if they overheat while charging.
Kleinberg said an overheating e-cig caused a mattress to catch fire at one local house, but the flames were quickly extinguished by a resident.
"If he didn't do that right away, it would have been a different story. It would have been a building fire instead of just a small item on fire," Kleinberg said.
On Wednesday, an e-cig exploded while being charged, sending bits of burning battery flying into the ceiling and walls, Kleinberg said. One hot piece of battery landed on a pillow, causing it to smolder and filling the house with smoke, he said.
Neither fire spread beyond the rooms where they started, but the potential for catastrophic damage was there, he said.
"Some of the batteries are failing in them or they are being overcharged," Kleinberg said. "We just wanted to put a warning out there that people need to take precautions using some of these devices. Just unplug it when you go to bed. Make sure you have a working smoke alarm."
He said e-cig users should follow the manufacturer's instructions concerning the devices.
"A lot of these devices are not really regulated right now; some of them are UL listed and some are not, some aren't tested at all," he said.
Most regulated electronic devices go through safety analysis conducted by Underwriters Laboratories or another nationally recognized testing laboratory before hitting the market.
Laws defining regulations and testing standards for electronic cigarettes are still in their infancy.