Warning: Scientists say gas cans carry risk of explosion

Red plastic portable gasoline containers – consumer gas cans sold throughout the U.S. – pose a rare but real explosion hazard many Americans may not know about, an NBC News investigation has found.

"It was ‘boom.’ That was it," said William Melvin, who suffered severe burns on one-third of his body when a gas can he was using allegedly exploded. "It was a miracle that I was still alive."

American consumers buy approximately 20 million gas cans each year, and there are more than 100 million plastic gas cans currently in circulation in the U.S., according to industry estimates.

But lab tests indicate that under certain limited conditions, gas vapor mixtures can explode inside those cans and cause significant injury. At the request of NBC News, the federal government's Consumer Product Safety Commission analyzed incident and injury databases and counted at least 11 reported deaths and 1,200 emergency room visits involving gas can explosions during the pouring of gasoline since 1998.

The results of scientific tests conducted at Worcester Polytechnic Institute's combustion lab with the support of the gas can industry, published earlier this year, show the conditions under which so-called "flashback" explosions inside the cans are possible. Other tests conducted for plaintiffs' attorneys, for a government criminal investigation, and for NBC News all reached the same finding.

The tests show that under certain limited conditions -- including a very low volume of gasoline left inside -- a flashback explosion can occur inside a plastic gas can, when gas vapor escaping the can contacts a source of ignition such as a flame or a spark. The vapor outside the container can ignite and "flash back" inside the can. If it does, and if the gas/air vapor mixture inside the can is a certain concentration, that mixture can ignite and cause an explosion of flame.

The test findings are the latest development in a long-running legal battle between can manufacturers and plaintiffs who have filed product-liability lawsuits.

Attorneys have filed at least 80 lawsuits during the past two decades on behalf of individuals injured in alleged gas can explosions. They have argued that portable plastic gas cans are "dangerous" and "unsafe" because they are "susceptible" to flashback explosions. Most of the lawsuits have named as defendants Blitz USA, until recently the largest manufacturer of plastic gas cans, and Wal-Mart, the largest seller.

Robert Jacoby, now 27, sued after a Blitz can he said he bought at Walmart allegedly exploded in his hand in 2010 while he was reaching down to put it on the ground in his front yard.

"It was just a big gas bomb right in my face," Jacoby told NBC News. "It blew up, covered my whole body just head to toe."

Jacoby said he had poured gasoline from the can onto a brush pile he planned to ignite, but had walked the can 20 feet from the pile when it exploded. He said he had not yet lit a match or any other fire, but claimed a spark from static electricity created by the friction between the plastic can and his denim jeans was the source of ignition.

A fire investigator hired by Jacoby's attorney examined Jacoby's property in the presence of Blitz representatives and says he found no evidence inconsistent with Jacoby's claim, and no evidence that Jacoby had lit the brush pile or that the brush pile had burned.

Jacoby suffered severe burns over 75 percent of his body. He spent four months in a hospital burn unit, and had multiple surgeries and skin grafts, incurring $1.5 million in medical bills. Scar tissue covers most of his torso and arms.

Karen Kornegay sued after her 19-year-old son, Dylan, died in 2010 from the effects of third- and fourth-degree burns he received over 80 percent of his body following an alleged gas can explosion.

Kornegay said her son had poured gasoline from a Blitz can purchased at Wal-Mart to start a bonfire with friends. She said Dylan's friends told her he was walking away from the fire when the can swelled and exploded near his leg, and engulfed him in flames. Dylan spent six weeks in a burn center, underwent 15 surgeries, including the amputation of part of his leg. He succumbed to an infection while at the burn center.

"Dylan was the victim of a gasoline container," said Kornegay, "that blew up."

William Melvin sued after a Blitz can he said he bought at Wal-Mart allegedly exploded in his hand in 2009 while he was refueling his riding lawnmower with the engine off.

Melvin told NBC News he had been mowing, but after the mower ran out of gas he pushed it a few hundred feet to his garage shop, where he had gasoline stored in several plastic cans. About 15 seconds after he started pouring from one of the cans, Melvin said, he saw a flash of fire.

"The gas can exploded and blew me back into the shop," Melvin said.

Melvin suffered severe burns on his face, arms, legs and all of his torso and spent weeks in a burn unit. He has largely recovered and has returned to his work as a racecar body repairman.

Attorney Diane Breneman has represented Jacoby, Kornegay and Melvin, and about 30 other plaintiffs.

"Any time a spark or flame gets near a can, you are holding a potential bomb," said Breneman. "That's the reality of it. … It's not a safe product."

The plastic gas can industry disagrees. "Today's gas cans are very safe," said William Moschella, an attorney for the Portable Fuel Container Manufacturers Association, a trade group of plastic gas can manufacturers. "They are used billions of times a day without incident by people who use them appropriately."

Moschella noted that all plastic gas cans are imprinted with warnings that "vapors can explode" and "can be ignited by a flame source many feet away."

In lawsuits, Blitz and other manufacturers have argued that any alleged injuries were caused by the users’ own negligence and misuse, and that the cans were not at fault.

The defendants argued that Robert Jacoby was negligent because he was using gas to ignite a brush fire, that Dylan Kornegay was negligent because he had used gas to ignite a bonfire, and that William Melvin was negligent because he poured gas into the tank of a mower with an engine that was not cool.

Jacoby maintains he never ignited the brush fire. Kornegay's mother acknowledges that her son's use of gas to light a bonfire was a mistake, but claims he would not have died if the can had not exploded. Some fire experts say that while pouring gas on a fire may cause the fire to flare up and burn someone, it's the explosion involving the gas can itself that covers the victim in flames and causes catastrophic injuries.

Melvin acknowledged that his mower's engine was warm, but contends that it's standard practice for many consumers to add fuel to engines that are off but not completely cool.

The American Petroleum Institute and others publish gasoline handling precautions which warn consumers to "put gasoline in a small engine (like a lawnmower) only when the engine and attachments are cool."

Moschella told NBC News that most of the alleged incidents of internal can explosion have involved consumer misuse – such as pouring gasoline on a fire. He argued that all the incidents more likely have resulted from vapor explosions occurring outside the cans, and asserted that no one has proven in court that an explosion incident resulted from an ignition inside a can.

"This is really only occurring in a laboratory environment," Moschella said. "We haven't seen a case where that has been demonstrated."

"It's not clear at all that what is occurring in the real world, in real life, is that gas cans are exploding," said Moschella.

Gas Cans Alleged 'Defect': No Flame Arresters

The lawsuits allege that all the incidents were flashback explosions of the kind WPI's results demonstrated, from ignitions inside the cans.

They allege that the gas cans are "susceptible" to such internal combustion explosions and are therefore "dangerous," "unsafe" and "defective" for a specific reason: because their design does not include a flame arrester, a part the lawsuits allege could prevent flashback explosions.

Flame arresters -- pieces of mesh or disks with holes that are intended to disrupt flame -- are in use in metal "safety" gas cans, in fuel tanks, and in storage containers of other flammable liquids such as charcoal lighter fluid and rum.

"Any can that doesn't have a flame arrester is unsafe, period," said Breneman, the plaintiffs' attorney.

The gas can industry is "intently" studying whether to add arresters, said Moscella. "We can only add that to the can if it won't make the can less safe."

Dylan Kornegay's mother Karen has started a website in her son's given first name, Matthew, to educate others about the hazard of plastic gas can explosions. The website is called "Matthew Didn't Know."

"Dylan didn't know. I didn't know," Kornegay said. "He didn't have to die. His injuries could've been so much less."

After inquiries from NBC News and a review of both injury reports and flame-arrester engineering the Consumer Product Safety Commission issued a statement calling on the consumer gas can industry to incorporate flame-arrester technology into its gasoline containers.

"CPSC believes that this technology also should be included in gasoline containers," the statement said. "CPSC is calling on the industry to regain the momentum that was lost in years past by designing their products to include this safety technology. In addition, CPSC is asking voluntary standards organizations to incorporate a flame arrestor system into applicable safety standards for gas cans."

More from NBC News Investigations:

Follo w NBC News Investigations on Twitter and Facebook