Incidents like the thwarted 'shoe bomber' incident in late 2001 and last year's suicide bombing on a Russian aircraft have inspired U.S. authorities to look for better ways to check airline passengers for bombs. The Transportation Security Administration is now trying out a new machine that could make pat-down searches a thing of the past.
Checking baggage for explosives hasn't been a problem. Airport security can put bags in x-ray machines, open them up to look inside, or use advanced technology that can detect traces of chemicals often used in explosives.
But checking people's bodies is not so easy. A TSA initiative that began last September to rigorously frisk more people led to dozens of sexual harassment complaints. So the agency has now installed what looks like a longer, more complex walk-through metal detector in nine airports around the country. The machine -- called an Explosive Detection Trace Portal - tests the air for traces of explosives.
"The machine actually will talk to the individual, tell them to stand inside and wait, and as soon as they are cleared, it will tell them to proceed," explains Jose Ralls, TSA Director for McCarran International Airport in Las Vegas, where two of the detectors are in place.
Mr. Ralls watches as a passenger is screened. "Now he knows to go on through," he says, "and he just waits, and as soon as the air is analyzed he will be able to proceed forward."
The machine blasts air downward and across the individual inside the portal. Mr. Ralls says the experience often startles travelers. "That is why our people are out there, to explain to them the noise that they will be hearing," he says.
The way it's supposed to work is that suspicious particles on clothing and exposed skin get blasted toward the floor -- where, within seven seconds, the machine can detect 40 different types of explosives. If any are found, security is alerted.
According to the manufacturer, Smith Detection, the portals have an error rate of less than 1%. Company vice president Mark Lastra says the technology is commonly used elsewhere, mostly in "highly controlled facilities, such as nuclear power plants and government buildings with high security needs."
The TSA hopes the technology will also cut down on passenger wait times. The agency is collecting data from the airports in the test phase to determine whether the machines are faster and more efficient than human inspectors.
So far, the detectors have received mixed reviews from passengers at McCarren.
"It's going to make me feel a lot safer on the flights," said one traveler. But another worried that the machine might wrongly single out people who work with gunpowder or other chemicals. "People do absorb chemicals from the different jobs that they do," he observed. A third passenger said she didn't think the technology went far enough. "Going back to September 11th," she said, "this probably wouldn't have stopped it from happening. So maybe people have to be more inventive now."
The Transportation Security Administration plans to deploy five more of these portals elsewhere in the nation over the next three months, and eventually would like the explosivedetectors to be as common as metal detectors.