A man in England doused himself with gasoline in his apartment and then ignited the “petrol vapours” with a cigarette lighter and burned himself to death in a ball of fire. Two police officers armed with TASER Conducted Energy Weapons had been called to the scene by paramedics, but they were unable to deploy these devices fast enough to abort the blazing suicide.
Later a question arose: If the officers had discharged their CEWs, could that in itself have ignited the fumes, “killing the man they were trying to save, and even themselves?”
An investigator on the case, Chris Clarke, joined forces with another British forensic fire investigations expert, Stephen Andrews, to find out.
In a study recently published, they conclude that, depending on “numerous variables,” the discharge of a CEW in a flammable environment “could prove fatal not only to the target but to the operator as well.”
In the paper describing their work, Clarke and Andrews cite six news stories worldwide that have reported incidents in which subjects are believed to have died from burns inflicted when CEWs were used in the presence of gasoline. “Most published research” on CEWs and flammable vapors, however, has concentrated mainly on pepper sprays and certain “explosive formulations, which are sensitive to electrical discharge.”
The goals of the current study were to confirm
- whether a TASER CEW is “capable of igniting a person who was doused” with gasoline, “one of the most hazardous chemicals the general public can come in contact with,” and
- whether CEW deployment in an enclosed room can cause a gasoline vapor explosion “which might injure or kill all occupants.” On the latter question, the investigators claim, “[t]here is apparently no previous research.”
After some trials with laboratory “bench models,” Clarke and Andrews performed a series of full-scale experiments on a “fire test dummy”–a life-sized wooden mannequin, intended as a “human target simulant.” In some tests, a swatch of pig skin, which has “similar characteristics to human skin,” was affixed to the dummy’s chest. A polyester/cotton shirt and various pieces of clothing were also added and in some cases these were wetted slightly with saline solution “to represent a person sweating in a stressful situation.”
Probes from a TASER X26 were either physically implanted or fired. Of the implanted probes, one was pierced into the dummy’s “chest”; the other was pushed through the shirt fabric “above the timber surface,” to represent a “clothing disconnect.” The probes were moved in different configurations during the experiments, always with the goal of creating strong electrical arcing.
A final variable involved the gasoline. From 100 milliliters to 4 liters (about a gallon) of BP unleaded was doused on the mannequin’s chest and allowed to vaporize from 30 to 60 seconds before the CEW was activated (suggesting time that an officer might spend trying to verbally control a suicidal subject who was intending immolation).
As the variables were changed, ignition of the fuel did not always occur. But flames did break out with impressive enough reliability–sometimes in the millisecond just before fired probes even reached their target–for the researchers to conclude that the CEW “is a competent ignition source” for gasoline and “may ignite a petrol-soaked person…when fired into them.”
Most dramatic were the test firings conducted inside a 20-foot shipping container, meant to simulate a typical room. Here the gasoline-soaked test dummy was hung on the rear wall and a second mannequin, representing an officer configured in the CEW-firing position, was positioned 13 feet away. A TASER bound to the “officer’s” hands was activated by a cord pulled from outside the compartment.
When the CEW discharged, the room was instantly engulfed in flames. In less than 1.5 seconds, heat at the officer’s head and hand level reached nearly 800 degrees Fahrenheit. “The police mannequin showed severe [burns] to about 20% total body surface area,” the researchers report. (The dummy’s Kevlar vest tended to protect the chest area.) For the suspect mannequin, there was “almost 100%” total body surface burned–“very probably fatal for a person if accompanied by inhalation injury.”
For an officer to be safe when firing into a “vapor-rich” room, the researchers conclude, he or she would probably have to be farther away from the target than the full range of the CEW wires.
“There may be many occasions where ignition does not take place” because the necessary variables do not align within explosive limits, Clarke and Andrews explain. But trainers need to warn officers of the possible risks, they write.
“It is [our] opinion…that the only advice and training that can be given to law enforcement personnel is not to discharge TASER devices in any circumstances where the possibility of flammable vapour exists.”
Atty. Michael Brave, national/international counsel for TASER International, Inc., cites this hazard warning: “CEW use can result in a fire or explosion when flammable gases, fumes, vapors, liquids, or materials are present. Use of a CEW in the presence of a fire or explosion hazard could result in death or serious injury. When possible, avoid using a CEW in known flammable hazard conditions.”
For litigated incidents involving CEW-induced fire injuries, Brave suggests consulting Brown v. Burghart, 2013 WL 1334183 (E.D.Pa., Apr. 3, 2013) and Mohney v. Hageter, 2013 WL 391155 (W.D.Pa., Jan. 30, 2013).
An abstract of the Clarke-Andrews study, titled “The ignitability of petrol vapours and potential for vapour phase explosion by use of TASER law enforcement electronic control device,” can be accessed free of charge at the website of the journal Science and Justice by clicking here. The full report is also available there for a fee.
Co-author Chris Clarke, a partner with Fire Investigations LLP in London, can be reached at: firstname.lastname@example.org.
Our thanks to Dr. Mark Kroll, a CEW researcher and adjunct professor of biomedical engineering at the University of Minnesota, for alerting us to this study.