July 7, 2016
With each terrorist attack on another airport, train station or other public space, the urgency to find new ways to detect bombs before they’re detonated ratchets up.
Chemical detection of explosives is a cornerstone of aviation security. Typically called “trace detection,” this approach can find minuscule amounts of residue left behind after someone handles an explosive. A form of this technology called ion mobility spectroscopy is what Transportation Security Administration officers are using when they swab and test your laptop, hands or other items at the airport. In a few seconds, a sample is vaporized, and the resulting chemical ions are separated by molecular size and shape, triggering an alarm if an explosive compound is detected.
But this method is labor-intensive and slow for large volumes of stuff, and its effectiveness can depend on the sampling skill of the officer. It relies on contact sampling, which requires security personnel to have access to surfaces where residue may have been left. That’s not useful if a bomber has no intention of going through a security line and having his personal effects searched.
Some security teams rely on dogs, which can be trained to sniff out explosives using their exquisite sense of smell. But the logistics and training involved with the routine deployment of canines can be arduous, and there are cultural barriers to using dogs to directly screen people.
What researchers have wanted to develop for a long time is a new chemical detection technology that could “sniff” for explosives vapor, much like a canine does. Many efforts over the years fell short as not being sensitive enough. My research team has been working on this problem for nearly two decades – and we’re making good headway.