By Dean Irvine for CNN
Adjust font size:
LONDON, England (CNN) -- It looks under your clothes and can see you naked. It's the new "Backscatter" X-ray security device and was installed by the U.S. Transportation Security Administration (TSA) at Phoenix Sky Harbor International Airport last week.
Los Angeles International and New York's John F. Kennedy Airport will be next to trial the device that for now will be used only as a secondary security measure.
People who fail the standard screening with a metal detector will have the choice between a scan from the "Backscatter" X-ray machine or a pat-down by security staff.
Passengers selected for screening by the device are asked to stand in front of the closet-size X-ray unit with the palms of their hands facing out. Then they must turn around for a second screening from behind. The procedure takes about a minute.
Since the foiled bomb plots on planes taking off from Heathrow Airport last summer, transport security officials have quickly tried to introduce ways in which to spot a new breed of potential terrorists' weapon.
Current devices at airports, from metal detectors to hand luggage X-ray machines, rely on technology that has not advanced much since the 1950s and cannot detect liquid or plastic explosives, ceramic knives or drugs.
The TSA has done its best to ally fears that security officials will effectively be seeing naked images of passengers. The manufacturers of the machine, American Science and Engineering, Inc, have been instructed to install an algorithm that removes most of the details from the images.
The result is an image that resembles a fairly simple pencil outline drawing, but one that would reveal any concealed objects. It doesn't completely get rid of your body's contours, but it does obscure your face.
This hasn't convinced some and India has ruled out using the machines after trialing them at New Delhi airport last year.
The Central Industrial Security Force that looks after airport security at India's airports claimed that the images the machines produced were too revealing and would offend passengers, as well as embarrassing their security officials.
Cultural sensitivities aside, many might feel uncomfortable with the idea of being seen naked by a stranger, even in an obscured form. But at Phoenix airport the device is 50 feet away from the security checkpoint so the officials who staff them would not be able to see you in the flesh -- to them you would just be a dehumanized black and white outline.
Passenger Kristen Rodgers, 22, of Little Rock, Arkansas, did not go through the screening, but likened it to going to the doctor.
"If you tell yourself they have to look at that all day long, it makes yourself feel better," she told the Associated Press. "If it's just for security, just for 45 seconds, I think it would be worth catching somebody with something harmful."
Just an electronic strip search?
Civil liberties groups had been wary of human X-ray machines in the past; the American Civil Liberties Union likening them to "nothing more than an electronic strip search."
"This technology brings an extraordinary potential for abuse. We certainly should not be using it in our airports before other, less intrusive alternatives have been tried out," said Barry Steinhardt, ACLU Associate Director, in 2002.
Those other alternatives include particle analyzers that blow air on passengers as they walk past and react if any explosive particle is detected. However trials of these walk-through machines have found them to be too glitchy and unreliable.
The TSA have done their best to ensure that images from the "Backscatter" X-ray would go no further than the airport and that they would be erased after they are viewed.
"Backscatter images will not be retained in the system, will not be capable of being printed, and will be deleted as each individual steps away from the machine," states the TSA on their Web site.
People worried about getting a lethal dose of radiation from the device also need not fret. A 10-second scan emits the same amount of radiation as two-minutes spent on a plane at 30,000 feet.
So given the choice, who would not rather undergo a 10-second scan, than face a possibly more intrusive hands-on search by a security official?
An image of a woman taken by the "Backscatter" X-ray machine.
Quick Job Search