A New Way to Detect
Liquid Explosives

The foiled terror plot in Great Britain aimed to exploit vulnerabilities in airport security, but new technology may help patch those holes. In recent months, the Transportation Security Administration has begun testing a new tool for detecting such materials, security industry sources tell TIME. The device, Ahura's FirstDefender, is a handheld chemical identification system about the size of a hardcover book. The FBI, U.S. Customs and Immigration and the Department of Homeland Security have already begun using the gadget to detect and identify chemical hazards, but it hasn't yet been implemented in airports. The TSA recently deployed two $160,000 explosives detection machines for Chicago's Midway International Airport, but those machines, known as puffers, aren't made to identify sealed liquids. The agency has yet to put into place FirstDefender devices, which cost about $30,000, though it now confirms that it is testing the FirstDefender. "Ports of entry need technology to identify dangerous substances within containers," says Ahura CEO Doug Kahn.

Older machines used to examine liquids were so large that they were generally anchored to labs. But given the portability of this 3.5-pound tool, the TSA could quickly deploy it in airports nationwide. The gadget is simple enough to use that airport screeners and security officials with just several hours of training could monitor suspicious materials in transit. In its latest iteration, the FirstDefender can identify 2,500 liquid and solid substances. The U.S. Army Edgewood Chemical and Biological Center issued a recent assessment of the new handheld as an effective portable tool in detecting dangerous substances, including sarin and mustard gas: "The FirstDefender can be suitable for (non-trace) field detection and identification of liquid that may contain CW [chemical weapon] agents," the report concluded.

The waterproof and shockproof device has already been used by hazmat teams in New York and Washington and in military operations, and Ahura has plans to develop an even smaller, cell-phone-size implement. How does the technology work? Explosive liquids tend to have strong chemical signatures, which the device can read, even through bottles or other containers. The technique employed, called Raman spectroscopy, uses a laser for optical analysis. After shining a light on a substance, liquid or solid, the device analyzes the optical characteristics of the scattered light that reflects back. "You can read the substance as if it had a bar code," explains Ahura founder Daryoosh Vakhshoori.