The Hazards of Flash-Bangs

Charlotte-Mecklenburg (N.C.) Police officer and SWAT veteran Fred Thornton was killed late Friday, when a flash-bang device apparently exploded while he was securing his tactical gear in an agency vehicle in front of his home.

This news item surprised POLICE Magazine, because these tactical tools have proven themselves over and over again for the officers who use them to flush out barricaded suspects or enter a building to arrest a high-risk suspect.

CMPD investigators are now sorting out the details of the accident that claimed the life of Officer Thornton, who was the longest-tenured tactical officer with the agency. So we'll have to wait until they finish their work.

However, it should be pointed out that diversionary devices, or "flash-bangs," pack a punch — heat exceeding 1,000 degrees Fahrenheit, a blast reaching 175 decibels and a flash of 1 million Candle-power. As such, safe handling of them is a must.

"Certainly in my position seeing thousands of deployment reports, we emphasize that these are extremely dangerous devices," Don Whitson, a 23-year SWAT veteran with the Fort Collins (Colo.) Police Department, tells POLICE Magazine. "But the trade-out for the safety of the citizens and officers outweighs the dangers of handling them."

Whitson, who teaches a National Tactical Officers Association (NTOA) course on less-lethal weapons, said he was unaware of an officer death caused by a flash-bang device, but acknowledged that it would be possible. Whitson's 40-hour course covers chemical agents, flash bangs and impact projectiles. He introduces officers to the range of less-lethal deployment options that include aerosol, blast grenades, and launched ferret rounds.

"I'm aware of a number of injuries, but I'm not aware of any deaths," Officer Whitson adds. "I've heard anecdotal reports of suspects injured and killed."

As Officer Whitson notes, flash-bang devices aren't like traditional grenades, because the devices don't spray shrapnel when the pin is pulled. The flash exits a circle of small vents, or ports, at the top of the approximately 5-inch-tall device.

In fact, these devices are manufactured with a steel casing that contains the "bang," forcing the explosion upward and through the vents. They usually arrive at the law enforcement agency in two pieces — a body made of hardened gun steel and a metal fuze assembly with attached charge. To assemble the device, an officer screws the fuze and connected charge into the body.

The devices deflagrate using a derivative of black powder called flash powder that provides a quicker, more spontaneous explosion. Each manufacturer offers a proprietary blend of aluminum powder, magnesium and ammonium perchlorate in the flash powder.

Note: A photo that originally ran with this blog depicted a CTS flash-bang device. This was not intended to associate CTS with the Charlotte tragedy. A CTS device was not involved.

Related:

N.C. SWAT Vet Dies From Flash-Bang Blast While Securing Gear

N.C. SWAT Officer's Funeral Relocated to Larger Church

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