Warning: Batteries are included.
Dell Inc.'s recall Tuesday of 4.1 million laptop computer batteries at risk of fire raised the specter of the average person unwittingly toting an arsenal of potentially lethal incendiary devices including cellphones, personal digital assistants and portable music players.
Rest assured, the risk of a cellphone burning your hair off is considerably lower than rear-ending someone while talking on the 210 Freeway. But the lithium ion batteries that power Dell laptops and other essentials of life on the go have long been known to burst into flames from time to time.
Physically and chemically, the release of energy that makes your iPod rock is a delicate process. The rise of laptops, BlackBerrys and Game Boys has made lithium ion batteries so prevalent -- U.S. consumers bought 1.2 billion last year -- that it's almost impossible to go a day without using something that might catch fire for no apparent reason.
So in a world of terrorism alerts and trans fats, what's the relative danger of self-immolating gadgetry? Somewhat more than getting killed by lightning, but somewhat less than dying from food poisoning.
"There's no such thing as a zero risk in the world," said James Kapin, chairman of the American Chemical Society's Division of Chemical Health and Safety in Washington. "I have a 25-mile freeway commute; that's a pretty significant risk that most people don't think about. The risk of a laptop battery exploding is very, very low."
That reassures people such as David M. Lynch of Brea -- to an extent. The 52-year-old marketing executive doesn't fret about a cellphone flambe.
"I'm not terribly worried about my hair catching fire," he said. But he has stopped setting his laptop in his lap to allow better ventilation. "I really have to put it on a tray now, because it does heat up."
Dell recalled the batteries for 33 laptop models after receiving six reports of overheating. Last year, concerns that the batteries posed fire hazards prompted Hewlett-Packard Co. and Apple Computer Inc. to recall hundreds of thousands of batteries.
The Consumer Product Safety Commission logged 339 reports from 2003 to 2005 involving potentially faulty laptop computer batteries and cellphone batteries, spokesman Scott Wolfson said. The incidents ranged from smoking and charring to laptops bursting into flames. No one has been seriously injured.
It's the downside of better living through chemistry. All batteries produce electricity through chemical reactions. When you turn on a device, the reaction starts by running electrons between the battery's two oppositely charged electrodes.
Lithium ion batteries -- named for the lithium hexafluorophosphate inside them -- pack large amounts of energy into a small space. That makes them ideal for power-hungry portable devices. They also generate a lot of heat. Even a microscopic defect in the battery's innards can let the heat get out of control.
Laptops are particularly vulnerable because the other components also generate a lot of heat, but "every consumer device you own -- a cellphone, an MP3 player, a PDA -- they're all powered by lithium ion batteries," said Carmi Levy, a senior research analyst at Info-Tech Research Group in London, Canada. "This is not an issue that's strictly limited to Dell. This is not an issue that's strictly limited to laptops. It covers the entire consumer electronics space. I would expect manufacturers of all types of consumer electronic products would look very closely at their devices."
The Consumer Product Safety Commission has issued recalls of products with potentially faulty battery packs -- including cameras, flashlights and crib mobiles.
In 2004, the Federal Aviation Administration and the Research and Special Programs Administration banned cargo shipments of non-rechargeable lithium batteries aboard passenger planes, saying they posed a fire hazard when transported in the cargo hold, where the fire suppression systems couldn't put out the flames.
Systems in the passenger cabins, FAA spokesman Laura Brown said, can put out such fires.
Brown said the FAA and the group that regulates transport of hazardous materials were completing a study of fires involving rechargeable lithium ion batteries in the holds of planes.
After receiving reports of incidents and injuries involving cellphone batteries, the Cellular Telecommunications and Internet Assn. joined with the product safety commission in issuing guidelines last year for the proper care and handling of lithium ion batteries.
Don't drop them, put them on or near a hot surface or get them wet.
"You've got electricity, you've got heat and you've got reactive chemicals, so there's certainly a potential for something bad to happen," the American Chemical Society's Kapin said. "A fire, an explosion, something like that."