Sandia LabNews

Improved stun device is reusable

Reusable explosive device offers help to law enforcement

Before a crowd of business-suited observers, the slender man in running shoes hurls a cannister about the size of a small soda can into the concrete-walled room — a test cell in the rear of Sandia’s Explosive Components building.

The explosion’s extreme brightness and sharp report — like a flashbulb going off a foot from the eye, a firecracker a foot from the ear — momentarily daze a reporter who has arrived too late to don ear plugs and sunglasses.

A pungent cloud of white dust drifts toward the observers, most from Washington.

"The smell of victory," says one, sniffing.

The nonlethal, newly patented device, developed by Mark Grubelich (2552), is of interest to law enforcement officials as a cheaper, safer way than those currently used to stun kidnappers or terrorists in a room where hostages are kept at gunpoint.

Violence contained

The observers — "mostly from organizations with ‘I’ as one initial," says one — know that the idea is to break down a door or window, quickly toss in a diversionary device (also called a stun grenade or flash-bang), and take advantage of the baddies’ resultant disorientation to capture, disable or, if unavoidable, kill them while freeing their victims.

However, most devices currently in widespread use — mostly based on technology developed at Sandia — contain a metal powder that violently combines with a salt containing oxygen. When this mixture — aluminum and potassium perchlorate — is ignited by a grenade-style fuse, an explosion takes place within the body of the device. This creates a zone of extreme pressure nearby — dangerous if the device lands near a hostage’s neck or head. The explosion also destroys the shell of the device containing the explosive, making such apparatuses expensive to use as training tools.

The new device lobbed by Mark is made of plastic and contains only metal powder and no oxidizer. Instead of ignition within the cannister, the particles are forced like a burst of talcum powder out through 16 quarter-inch-diameter holes in the bottom of the structure. The ejected particles hang momentarily in air, "flared like a peacock’s tail," says Mark. They form a sheet of metal dust about five feet in diameter before igniting by combining with oxygen present in the air. The distributed powder means that the pressure in the immediate vicinity of the exploded device is lowered to a safer level. It also means that the cannister is undamaged and can be reloaded for a few dollars, making it easy to use as a training device.

The new configuration is also simple to adapt for a variety of law enforcement needs. Prison officials require a grenade that, if remaining whole after use, is too soft and flexible to be used as a blackjack by rioting convicts. Soldiers require a lightweight cannister that can be carried over long distances. Police can carry the cannister in their cars, so weight is not a factor, but they want no explosive material within the cannister so any that fall into the wrong hands can’t be restructured into a bomb.