SFO bag checkers flying blind 

click to enlarge Deeper look: Airport scanning machines’ “slicing capability” allows screeners to closely examine the contents of luggage using technology similar to that of a CT scan machine, left. - COURTESY PHOTO
  • Courtesy Photo
  • Deeper look: Airport scanning machines’ “slicing capability” allows screeners to closely examine the contents of luggage using technology similar to that of a CT scan machine, left.

Baggage screeners at San Francisco International Airport warn that the Transportation Security Administration has disabled a key function of the multimillion-dollar X-ray machines that scan the contents of every bag leaving SFO.

After airport ticket agents deposit passengers’ luggage on a conveyor belt, screening machines using CT scan technology determine whether the bags pose a threat. Bags deemed safe continue to the plane, but bags that trigger an alarm go to Level 2 inspection. Screeners say it is there that the machine’s so-called “manual slicing capability” is sorely needed.

This slicing function enables baggage screeners to zero in on suspicious bags by creating a computer-generated image of a particular cross-section. They compare the densities of objects inside bags to the densities of known airline threats. When they find a match, the machines automatically call for manual inspection, said Steve Hill, a former spokesman for machine manufacturer Morpho Detection.

SFO’s machines still provide one or two automatic slices, but several screeners call that insufficient. Without manual slicing, three screeners interviewed for this story say, they are ill-equipped to assure the safety of the luggage they are approving to travel on airplanes out of San Francisco.

Six longtime baggage screeners allege that every day, dozens to hundreds of bags identified as potential bomb threats are loaded onto planes at SFO without being inspected. Two weeks ago, after a year of inquiries by The San Francisco  Examiner, federal officials allegedly began investigating SFO’s baggage screening operation.

Screeners say the TSA disabled manual slicing, which allows workers to control the  slicing process, back in 2004, when the agency was weighing whether to keep alive its private partnerships with firms such as Covenant Aviation Security, which handles security at SFO. The changes made Covenant’s operation appear more efficient, but it dumped bags on the already short-handed baggage inspection room, whistle-blowers say.

“They wanted more output and more bags to be processed, but it just compounded the problem,” said one longtime baggage screener. Since inspectors are under immense pressure to process bags quickly, the screener added, “removing slicing invited corruption.”

Screeners said the time allotted to evaluate each bag has been reduced from nearly a minute to just seconds. In theory, screeners now have 15 to 20 seconds per bag, whistle-blowers said. But due to the machines’ speed, as many as five extra bags can enter a worker’s queue before he or she has finished the first bag. As a result, screeners often don’t get to bags in time.

In and of itself, this time reduction is not the problem, screeners say. Unchecked bags and those deemed to be threats are automatically redirected onto a belt leading down to Level 3 inspection, where Hill said bags are swabbed for explosives and either sent to the plane or — in extremely rare cases — destroyed by a bomb squad.

The problem lies in the fact that Level 3 inspections can take 15 minutes — time that Covenant management desperately wants to save, said Ron Davis, a retired SFO supervisor. As a result, screeners who flag “too many” bags are often switched to less busy terminals or pressured to clear more luggage, one screener said. And employees who violate security protocols are promoted, Davis said.

“Some supervisors are cheating,” said one screener. “If the real protocol were followed without cheating, they would see a drastic change in the number of suspect bags sent to the baggage inspection room, and they wouldn’t be able to handle it.”

A Covenant spokeswoman declined to answer any questions about the company’s use of scanning equipment.

But Covenant manager Fred Baptista quarreled with the notion that time was an issue affecting security.

“This is a place of procedures,” Baptista said. “It doesn’t matter if it takes 10 minutes or 10 seconds — you follow your procedure. No government agency is going to come in and tell you to work faster.”

Hill of Morpho Detection, the Newark-based company that built the airport’s baggage security system, said most bags flagged by machines are “false alarms” that don’t contain explosives. In general, he said, screeners nationwide rarely use slicing because X-ray machines can adequately scan most bags.

Jeff Price, an associate professor of aviation management who authored a textbook on aviation security, hypothesized that manual slicing may have been disabled because it caused screeners to send too many false alarms down to the inspection room and lengthen inspections.

“If that function was creating a high false-positive rate, then maybe it wasn’t working as well as they’d like it to be,” Price said.


Editor's Note: This story was corrected on August 31, 2012.


The August 30 San Francisco Examiner story “SFO bag checkers flying blind” improperly identified Steve Hill as an employee of Morpho Detection, a Newark-based maker of baggage-scanning machines. Although Hill was an employee of Morpho at the time he was interviewed, he is no longer employed by the company.

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Niko Kyriakou

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