Bill Pellan, director of investigations at the Pinellas County Medical Examiner's Office, said the Florida man's death was ruled accidental because the cause of death was a projectile wound to the head.
Tallmadge Wakeman D'Elia, a TV producer, was killed in a fire in his St Petersburg, Florida bedroom on May 5.
FEMA, a company that routinely keeps statistics on e-cigarettes and other vaping devices, reports that D'Elia's death is the first of its kind in the United States.
The pen exploded into pieces, at least two of which were sent into his head, the medical examiner said, ad he suffered burns on about 80 percent of his body. In this case, the autopsy noted that D'Elia was using a "mod" type e-cigarette manufactured by Smok-E Mountain.
The Florida man was found to be covered by burns as the exploding vape pen turned into a lethal projectile.More news: West Ham to appoint new manager in 10 days after Moyes departs
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Between January 2009 and December 2016, there were 95 reported incidents of explosions and fire involving an electronic cigarette, resulting in 133 injuries, 38 of which were severe, the U.S. Fire Administration said.
Though such incidents are rare, this isn't the first time a spontaneous e-cigarette explosion has raised concerns. Wilder told ABC Action News that he, as well as many other local store owners, won't sell unregulated e-cigarettes.
Use vapes with safety features, including protection against overcharging.
He explained: 'Any other e-cig that has a computer chip in it prevents that from happening'.
Smok-E Mountain, however, told ABC its e-cigarettes do not explode, suggesting instead that the device's battery or atomizer was likely to blame. In 2016, an e-cigarette exploded in a NY man's trousers pocket. "That's typically the biggest issue which causes batteries to fail", he said.