There has long been a conduit for used equipment between the U.S. military and law enforcement. Gear and guns purchased for warfare often find their way into the hands of badged civilian officers. Recently, however, there's been a new wrinkle in this relationship: Companies have been modifying and improving technology they first developed for the military and selling the upgraded versions to police agencies.

That's the story behind RedXDefense's new XCAT, a narcotics, explosives, and gunshot residue detection system. The XCAT was developed as the law enforcement version of the company's portable military explosive detector, the XPAK.

The XPAK was a breakthrough product, a man-portable explosive detection system that uses fluorimetric analysis (ultraviolet light analysis) to yield a visual signal that indicates the presence of the test substance. One characteristic of the rugged XPAK is that it is about the size of a military backpack. RedXDefense knew that if the police version of the XPAK was going to be a success it had to be much smaller.

The company's engineers quickly realized that much of the bulk of the XPAK was due to its large sampling surface, which is optimized to collect trace material over a large area. In contrast, the police version required only a small sampling area and only had to be rugged enough to survive fair wear and tear and being stored in a police vehicle. These two factors allowed engineers to significantly reduce the weight to one pound.

But much more went into developing the XCAT than just shrinking the XPAK. To be of optimum utility for law enforcement officers, the XCAT had to be a versatile system that could detect narcotics, explosives, and gunshot residue. What RedXDefense's management wanted was a tool that didn't exist, a handheld unknown substance analysis system that was accurate, versatile, and relatively inexpensive.

That was a tall order, according to Arman Ghodousi, product development manager for RedXDefense, who says research and development on the product took nearly three years. "These testing systems are usually designed for either narcotics or explosives but not both," he says. "But we finally reached a form factor that is conducive to law enforcement operations and can provide a single platform solution at an affordable price."

The XCAT is easy to use. All the operator has to do is select the test card that matches the suspected substance, then sample a trace amount of the substance on the card, and insert it into the machine. The chemistry happens in the machine, and the operator receives notice if the substance is present via a simple indicator, a red light for "yes" and a green light for "no."  Detection occurs in less than a minute, depending on the substance being analyzed.

Ghodousi says the XCAT is designed to replace cumbersome, multi-step colorimetric identification kits that officers often use in the field to conduct presumptive tests on suspect chemicals. "It achieves superior accuracy without the effort and the subjective analysis," he explains, "but it's not as accurate as spectroscopic analysis." However, spectroscopic systems are generally not used in the field because they are very expensive and somewhat fragile.

The company is currently shipping production XCATs to law enforcement agencies and commercial security organizations around the world.

Ghodousi says that one of the great advantages that the XCAT offers is RedXDefense's ability to add new test cards to its product line. For example, the company recently developed a card for detecting "bath salts" (the designer drugs mephedrone, methylone, and methylenedioxypyrovalerone (MDPV).

"The XCAT uses simple, proven technologies that we've reconfigured into a new form factor to deliver affordable and versatile detection capability," Ghodousi says. "We are really excited about it and about what it can do for law enforcement officers."

Editor's note: This story was updated on April 1, 2013.

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XCAT Detector