Scitech | Invasion of the body scanners

Airports use technology to get up close and personal with passengers

X-ray vision is usually the stuff of science fiction, available only to comic book heroes like Superman who wield the ability to selectively “see” through certain objects in order to find bad guys, fight crime, and make the world a better place.

In the real world, science has developed technology that appears akin to the superhero power, but in reality is much less refined and directed. Clark Kent’s idealized penetrative gaze cuts a couple of corners when it comes to physics. Still, recent applications have a similar, albeit more contested and controversial, goal: airport surveillance.

Last Tuesday, the federal government announced that airports across Canada would be introducing full body scanners – large portals that use electromagnetic radiation to detect a weapon or bomb a traveller may have concealed beneath their clothing – to enhance security measures for U.S.-bound flights. The investment was sped up in response to the December 25 attempted bombing of Flight 253, travelling from Amsterdam to Detroit.

Using electromagnetic waves to detect materials like metal, the rays are unable to penetrate very far below the skin’s surface, producing a reflected three-dimensional image of, essentially, a naked human body – accessorized only by any metal or plastic items stowed on a person.

According to the Canadian Air Transport Security Authority, the purchased portals belong to a new generation of scanners that use millimeter wave radiation, which, electromagnetically-speaking, is comparable to the microwave.

Shirley Lehnert, of the Montreal General Hospital’s Division of Radiation Oncology, said, “The energy of such radiation is too low to directly disrupt chemical bonds or cause electronic transitions.” She did, however, recognize there are some concerns with radiation such as this, which is also found in cell phones.

Another type of body imaging machine – first-generation scanners – use low-energy x-rays, which have a much higher frequency than millimeter waves. Frank Verhaegen, professor and head of research at the Maastro Clinic in the Netherlands, explained that the concern with these x-rays is the energy they deposit in your body during a scan – a potentially harmful effect, according to his research.

“It is well known that the lower their energy, the more damaging. X-rays do their damage by breaking DNA strands which may lead to genetic instability, cancer in the long-term, or acute diseases if the dose is high enough,” Verhaegen said.

While the millimeter wave technology is less damaging than these x-rays, Verhaegen was concerned about airports where the old x-ray scanners may still be in use. 

Beside the questions about health concerns, the scanners have also raised issues of privacy. Stéphane Leman-Langlois, associate professor of criminology at the Université de Montréal and author of Technocrime: Technology, Crime and Social Control, believes passengers should be turning their attention to this aspect of the technology.

“Scanners, with their actual impact on reducing terrorism or other crime, are in fact going to be used for other stuff…like a guy who forgot nail clippers in his…pocket,” said Leman-Langlois. “[Security guards are] going to catch a lot of these guys, whether they are trying to pass these things wittingly or unwittingly…. They’re going to catch zero terrorists.”

One reassurance seems to be that full body scanners do not disclose unique details about an individual’s identity: when your body is scanned, the security official does not discover your name or see your face.

However, the same cannot be said for other areas of surveillance research currently in development, like radio-frequency identification (RFID) tags for passports. Leman-Langlois explained that these computer chips can store information about identity and facial recognition, meaning that in the future, an airport official could scan a passport chip and instantly confirm you are who you claim to be.

“Any kind of card that contains information stored on an RFID chip is actually readable at a distance,” Leman-Langlois said. “But that means if [airports] can do it, anyone else can do it with less legitimate intentions.”

Leman-Langlois remained unconvinced that measures like digital passports and full body scanners would serve their security purposes effectively, pointing to the flaws of reactive security.

“The problem with this is that it assumes terrorists are going to try the same thing that they tried before,” he said. “In that loop of constantly reacting to small detailed actions that terrorists or criminals or whoever will come up with over the years, you’re never really going to catch up.”

Leman-Langlois called instead for proactive security, and old-fashioned investigation and intelligence.

“This is how you do security. It’s far less spectacular and it doesn’t have that appearance of the perfect, magic, one-security-fix that the portal has, but it works. The portal – we don’t know if it works or not.”

Scanners will be introduced to Canadian airports as soon as this month, but passengers can choose to submit to a physical pat-down instead, if they prefer.