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Thursday, January 7, 2010

EVER SINCE UMAR Farouk Abdulmutallab allegedly tried to blow up Northwest Flight 253 with explosives in his underwear, a debate has begun anew over the use and usefulness of full-body scanning technology that would have detected his secret cargo. The privacy concerns raised by these machines are understandable. But the precautions taken at every step to guard passenger privacy should allay any fears.

There are two kinds of "full-body" scanners in use by the Transportation Security Administration, the millimeter wave and the backscatter. Passengers using the millimeter-wave machines spend up to 40 seconds having their bodies scanned. The image produced is three-dimensional and looks like a fuzzy negative. Facial features are blurred. But the shape and contour of one's body are easily made out as the radio waves bounce off skin to create an image that allows screeners to check for concealed material that might be under clothing.

The TSA has ordered 150 backscatter scanners. These machines emit low-level X-rays at a passenger going through them. The result is a body image that looks like a chalk etching. Over the next year, the TSA plans to order another 300 scanners.

The TSA takes extra precautions to ensure the privacy of air travelers. The security screener with the passenger cannot see the image that's created. The picture goes directly to a secure and remote place where it is examined by TSA personnel who cannot see the passenger. The two TSA screeners communicate by wireless headset. Once the traveler has been cleared, the image is automatically deleted. According to the agency, the machine's ability to store, print, transmit or save the images is disabled when it is delivered to the airport. And here's one last precaution: Officers in that remote screening room are prohibited from bringing in cellphones, cameras or any device with a camera.

There are now just 40 millimeter-wave imaging scanners in operation at 19 airports, including Baltimore-Washington International Marshall Airport and Ronald Reagan Washington National Airport. Considering Mr. Abdulmutallab's success at getting a concealed explosive aboard an aircraft, thought must be given to making full-body scans a mandatory and primary security screen. The House passed an amendment last June proposed by Rep. Jason Chaffetz (R-Utah) that prohibited this. The Chaffetz amendment has yet to pass the Senate -- and it shouldn't.