See-through technology that stirred concerns about privacy of passengers being scanned at airports has been adapted for less sensitive use by the U.S. Border Patrol.
The agency is checking vehicles for hidden compartments and contraband with a breakthrough X-ray detection technology mounted in vehicles it calls Z Backscatter Vans, or ZBV.
The mobile device, loaded on a Ford F-350 pickup truck like a camper shell, can scan any vehicle, including semitrailer trucks, in minutes.
It can detect explosives, plastic weapons, nuclear, radioactive or organic threats as well as drugs, said Al White, patrol agent in charge of the Border Patrol’s station at Nogales, Ariz., about 60 miles south of Tucson. It also can detect stowaways, although White said the system won’t intentionally be used to scan for humans.
“This is closer to the vehicle cargo inspection systems used at most ports of entry,” White said. “It uses nonintrusive inspection technologies.”
So-called backscatter radiation technology uses a narrow, low-intensity X-ray beam the size of a laser pointer. The X-rays are reflected from their target to a receiver and then transmitted to a laptop in the truck’s cab that displays the images.
“It does not contain a source of radiation,” White said. “It creates its own X-rays by using an X-ray tube. Therefore, the safety zone is much smaller.”
In February 2007, the federal government began testing a machine at Phoenix Sky Harbor International Airport that used backscatter radiation to scan a person’s entire body. The low-intensity beam scanned the entire body at a high speed, and the amount of radiation given off was equal to 15 minutes of exposure to natural background radiation such as the sun’s rays.
Essentially, it looked through people’s clothing, and early versions showed the human body’s contours with embarrassing clarity. The Transportation Security Administration adjusted the equipment to give the image a line drawing likeness but still manage to detect concealed items. The TSA has stopped testing the backscatter devices because their leases ran out and haven’t been renewed, said Nico Melendez, a spokesman in Los Angeles.
Instead, another device, a “millimeter wave” machine, which began testing late in 2007 is now being used, still on a pilot basis, in about 20 airports around the country, Melendez said.
People who support using such scanners insist that they will ease detection of concealed objects like plastic weapons or liquids that traditional metal detectors miss. But critics in the United States and the European Union called the scanners an unacceptable invasion of human dignity.
The Border Patrol said the technology’s versatility is a huge boon for security and smuggling detection.
“This is what’s impressive,” White said. “It’s able to reveal things such as car and truck bombs, explosives . . . and other organic threats, radioactive threats including nuclear devices and dirty bombs. It’s capable of detecting low levels of radioactivity from gamma rays and neutrons. This is ideal for dirty bombs and conventional explosives. And on top of that, stowaways who could be illegal immigrants or potential terrorists.”