A recent investigation reveals that ubiquitous red plastic portable gasoline containers, which are available nationwide, present fairly unknown explosion hazards.

In the United States, consumers purchase some 20 million gas cans annually; there are about 100 million gas cans in circulation, industry estimates indicate, according to the NBC News investigation.

Laboratory testing revealed that under certain conditions, gas vapor mixtures within the cans can lead to injury. While risks are considered rare, injuries may be very significant. NBC News requested that the U.S. Consumer Product Safety Commission (CPSC) analyze injury and incident databases concerning injuries tied to gas cans. The CPSC reported back that, since 1998, no less than 11 deaths and 1,200 emergency room visits were associated with gas can explosions that occurred when gasoline was being poured, according to NBC News.

Test results published earlier this year from a study conducted at Worcester Polytechnic Institute's combustion lab-with the support of the gas can industry-revealed the conditions under which the explosions, referred to as "flashback" explosions, occurred inside the cans. Additional testing conducted for plaintiffs' attorneys, a government criminal investigation, and NBC News all reached the same findings, NBC News reported.

"'Is there a problem?' was the question," said Ali Rangwala, director of the combustion lab at Worcester Polytechnic Institute (WPI) in Massachusetts; Rangwala's team conducted the industry's test. "And our answer to that was, 'Yes, this is a problem.'... We definitely know that the problem exists, and we know that it's not a good idea, for example, to keep the can close to empty in your garages," he added, according to BayouBuzz.

Under specific, limited condition, such as when a small volume of gas remains inside the can, a flashback explosion can occur. When gas vapor escapes the can and makes contact with an ignition source, the external vapor may ignite, flashing back inside the can. If the gas and air mixture within the can is of a certain concentration, the mixture may ignite causing a flame explosion, the NBC New report revealed.

The paper indicated that, "Criteria for flame propagation to the inside of a portable gasoline container have been determined for fuel storage and pouring scenarios.... Extremely small gasoline volumes and/or low ambient temperatures produce conditions inside the PGC [portable gasoline container] that may allow flame propagation to occur." The WPI scientists found that certain conditions presented the greatest explosion risks inside of the gas can: a very small amount of gasoline inside of the can; cool temperatures; and tilting the gas can at a 42-degree angle, which is a typical pouring angle, according to BayouBuzz.

The findings are the latest in an ongoing legal dispute between industry and plaintiffs who have filed product liability lawsuits, according to NBC News. In fact, at least 80 lawsuits have been brought in the past 20 years over alleged injuries associated with gas can explosions. Plaintiffs claim the plastic gas cans are "dangerous" and "unsafe" because they are "susceptible" to flashback explosions, NBC News reported. The majority of the lawsuits name Blitz USA or Walmart as defendants.

In one case, a mam suffered severe burns on about 30 percent of his body when a gas can he was using allegedly exploded. Another man said that the gas can he was using allegedly exploded when he was readying to place the can on the ground in his yard. He suffered burns on about 75 percent of his body. Another young man, 19, died from this injuries after being burned over 80 percent of his body following an alleged flashback explosion. Another man told NBC News that his gas can allegedly exploded when he poured gasoline into his mower.

Industry argues that the plastic gas can are safe and the accidents are due to user error; however, plaintiffs and others argue the explosions are allegedly causing significant, catastrophic injury and loss of life. Lawsuits, according to NBC News, also allege that flame arresters-mesh or disks with holes widely used to interrupt flames in other products-could prevent flashback explosions. "CPSC believes that this technology also should be included in gasoline containers," the CPSC announced. "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."

Sources:

• NBC News; Warning: Scientists Say Gas Cans Carry Risk of Explosion; By Lisa Myers and Richard Gardella; December 4, 2013; http://investigations.nbcnews.com/_news/2013/12/04/21736375-warning-scientists-say-gas-cans-carry-risk-of-explosion?lite
• BayouBuzz; Scientists Show Plastic Gas Cans Can Explode; Media Sources, December 4, 2013; http://www.bayoubuzz.com/us-news/item/561421-scientists-tests-show-plastic-gas-cans-can-explode