One of the newest security screening technologies under examination by the TSA uses scattered X-rays to identify potential threat objects underneath a passenger’s clothing.

Backscatter machines emit low-dosage X-ray beams that create an image of a person when picked up by detectors. The technology is capable of detecting “the broadest range of threats, from ceramic knives to explosives”, says Joe Reiss, director of marketing at Billerica, Massachusetts-based American Science & Engineering (AS&E), manufacturer of the Z Backscatter personnel screening system.

AS&E was in August awarded a $722,000 contract by the TSA to upgrade the Z Backscatter system and deliver an advanced version of it for testing and evaluation. TSA chief technology officer Clifford Wilke says backscatter technology “holds a lot of promise”, but still needs work to address public privacy concerns.

Reiss notes that AS&E is working to overcome privacy concerns in two ways: by upgrading the technology itself, and by addressing the way in which it is used by security officials at the airport. On the former issue, he says the company is developing a “privacy enhancement filter” that will prevent screeners from seeing a detailed image of a passenger’s body. “This will remove the detail so all that appears on the screen is an outline of the person’s anatomy. Threat objects are overlaid on this image.”

The second privacy protection method is to ensure that the airport official who views the image is located remotely, away from the passenger checkpoint and, therefore, unable to see the face of the passenger undergoing X-ray screening. “The image analyst may be located in the airport, but will not be at the checkpoint. This person can instantaneously let the screener at the checkpoint know via two-way radio communication if a threat object is present and what type of threat it is,” explains Reiss.

Wilke describes backscatter technology as “new and groundbreaking”, but notes that that there remains a great deal to learn, such as how the system would work in an airport situation and how passengers would react to it. He adds that the TSA will “move accordingly” on implementing a pilot test that uses backscatter technology. The agency is already behind schedule on establishing a backscatter pilot; former TSA chief David Stone in December 2004 told delegates attending the American Association of Airport Executives’ Fourth Annual Aviation Security Summit that roughly four pilot tests would be launched in the second quarter of 2005.

Rapiscan Systems, a subsidiary of California-based OSI Systems, has also developed a backscatter security screening system. The Secure 1000 Backscatter system recently underwent a four-month pilot test at London Heathrow, OSI chairman and chief executive Deepak Chopra told a US House Committee on Homeland Security last month.

Source: Flight International