Every day, the Transportation Security Administration (TSA) screens 1.8 million passengers and their baggage at 450 different airports within the United States. It’s an overwhelming task, and yesterday a Congressional oversight committee heard just how overwhelming.
John Roth, inspector general of the Department of Homeland Security (which oversees the TSA), discussed the findings from covert testing of security operations at eight different airports. The results, he said, were “disappointing and troubling”; they included failures of technology, lapses in procedures, and instances of human error. Roth declined to give specifics, however—the names of the airports tested, the number of tests, and the actual results remain classified. Peter Neffenger, who took over as administrator of the TSA in June, also testified, saying that the TSA’s focus on efficiency—getting disgruntled passengers through the checkpoints quickly—had come at the expense of security effectiveness.
Airport security lapses are not limited to the United States. A recent study by Jenny Kathinka Kruger and Boris Suchan of the Ruhr University in Bochum, Germany, published in the journal Aerospace Medicine and Human Performance, points to similar problems with screeners at the Frankfurt/Main airport. Covert inspections there revealed that “Nearly every second bag containing a forbidden item (e.g., an improvised explosive device or IED) was transferred through the security check without any difficulties.” The authors looked at the conditions under which screeners worked as well as their training, and arrived at some startling conclusions: Screeners did not train with actual X-ray images of luggage, and there was little vetting of job candidates. “Almost every applicant is accepted,” note the authors, rather than hiring only those, for example, with the ability to mentally rotate the objects seen in the X-ray reading.
In yesterday’s hearing, TSA’s Neffenger said the agency is taking steps to streamline training, including enhanced instruction on the proper use of screening technology: “It turns out we hadn’t taught them how important it was to use it properly…. We actually told them how the equipment worked; that was something we hadn’t done before.” The agency is also reducing the number of procedures screeners are expected to memorize. “There were 3,100 separate tasks and 88 different forms of pat-down,” said Neffenger. “That’s impossible, there’s no one who can do that.”
There is at least some good news, however—it turns out that X-ray screening machines are safer than some people had feared.
In 2010, the TSA began installing X-ray backscatter machines in U.S. airports. The agency had been using a small number of X-ray machines since 2008, but they were meant to complement existing systems that used millimeter waves (a type of non-ionizing radiation) to detect metal weapons and explosives concealed on passengers’ bodies. After the 2009 “underwear bomber” incident (in which a terrorist attempted to detonate plastic explosives he had smuggled on board a Northwest Airlines flight after passing through a standard security screening in Amsterdam), X-ray machines were installed as primary systems, particularly in “category X” airports, which, because of the amount of passenger traffic they receive, are considered more likely targets for terrorist attacks.
The X-ray machines immediately raised privacy concerns: The images of screened passengers were extremely detailed, clearly showing genitalia as well as any body piercings or prosthetics. TSA asked the machines’ manufacturers to develop software that would display a generic figure, almost like a chalk outline. But when Rapiscan Systems, the manufacturer of the X-ray backscatter units, was unable to comply, TSA removed all 250 X-ray machines from U.S. airports in 2013.
In addition to privacy concerns, the X-ray machines raised questions of cancer risk due to radiation. In 2011, the European Commission had banned body scanning backscatter X-ray machines “in order not to risk jeopardising citizens’ health and safety.” A PBS Newshour/ProPublica story that aired around the same time reported that “the TSA conducted only limited tests on the backscatter machines [before they were installed], and no independent safety tests had been done at all.” David Brenner, the director of the Center for Radiological Research at Columbia University Medical Center, was quoted saying that the odds are one in ten million that people will develop cancer as a result of a backscatter scan. “It’s a very small risk,” Brenner said, “but if a thousand million people walk through these machines, it’s a whole different ballgame.” Brenner predicted that when fully deployed, backscatter scanners could cause cancer in 100 travelers each year.
Because TSA is currently evaluating second-generation X-ray backscatter machines for use in airports, the Department of Homeland Security asked the National Research Council to study the radiation risk to travelers from these devices. The NRC’s findings have now been released and published by the National Academies Press.
The study had two objectives: To determine if the machines complied with current health and safety standards regarding radiation, and to make sure they had safeguards in place to prevent overexposure to radiation (due to accidental failure or deliberate tampering, for instance). The committee was asked not to evaluate whether the existing standards adequately protect human health.
The NRC panel concluded that the machines comply with current radiation risk standards, and that “the dose received under worst-case scenarios of...system failure, those failures that result from the beam becoming stuck while still producing X-rays, does not exceed the applicable standard and therefore cannot result in overexposure.”
The committee also evaluated whether special populations, including children and developing fetuses, as well as frequent flyers and airline and airport staff who might be expected to get more frequent screenings, could be at higher risk. Here too, they found no evidence to support such a concern.