Electronic cigarettes—also called personal vaporizers or electronic nicotine delivery systems—are perceived by many smokers as a safer alternative. But according to a recent report from the U.S. Fire Administration (USFA), e-cigarettes come with their own unique risks: namely, fires and explosions.

In fact, a number of recent fires have been attributed to e-cigarettes, causing some concern within the fire service community, according to the USFA. To better understand the problem, the USFA examined media reports of 25 e-cigarette fire incidents in the U.S. dating from 2009 through June 2014, which is not a complete list.

• The battery in the device was being charged in 20 incidents.
• Two incidents occurred during use.
• It wasn’t clear in two incidents whether the e-cigarette was in use, idle or being charged.
• One incident occurred during transportation on a cargo aircraft.
• Ten injuries and no deaths were reported by the media.
• Several burn injuries were reported. Two serious injuries occurred when devices exploded in users’ mouths.

The media reports generally characterize these incidents as explosions because the event occurs suddenly and is accompanied by a loud noise, a flash of light, smoke and flames. The battery or other components were ejected under pressure and are described by the media as flying across the room, often igniting combustible items where they landed. Luckily, most fires were minor, resulting in damage to carpets, drapes, bedding, couches or vehicle seats.

As you might expect, several lawsuits have been filed against e-cigarette manufacturers for injuries received when the e-cigarettes exploded. The most recent suit was filed in Salt Lake City on Nov. 4. According to published reports, the e-cigarette unexpectedly blew up while a man used it at his home in February 2013. The explosion sent burning debris and battery acid into his mouth, face and eyes and caught his hair on fire, the lawsuit says.