Aviation securityBackscatter body scanner making a comeback

Published 29 July 2014

Airline passengers have already said bon voyage to the controversial backscatter X-ray security scanners, pulled from U.S. airports in 2013 over concerns about privacy and potential radiation risks. The devices may, however, be reintroduced in the future, in part because they produce superior images of many concealed threats, and Congress still wants to know whether these systems — currently used in prisons, in diamond mines, and by the military — produce safe levels of radiation for screeners and the people they screen.

Airline passengers have already said bon voyage to the controversial backscatter X-ray security scanners, pulled from U.S. airports in 2013 over concerns about privacy and potential radiation risks. The devices may, however, be reintroduced in the future, in part because they produce superior images of many concealed threats, and Congress still wants to know whether these systems — currently used in prisons, in diamond mines, and by the military — produce safe levels of radiation for screeners and the people they screen.

Two years ago, researchers from the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, produced a report stating that the radiation exposure levels produced by one widely used class of backscatter machines were in compliance with applicable national and international safety standards. A NIST release reports that to evaluate these results, as well as similar findings at other institutions, Congress ordered an independent third-party assessment of the backscatter systems to be carried out by a team selected by the National Academy of Sciences (NAS). Last week, NIST hosted the NAS study at the Gaithersburg campus, in a lab that contains a government-surplus backscatter machine that once screened passengers at LaGuardia Airport.

Government agencies regularly ask the National Academies to conduct in-depth studies, says Erik Svedberg, senior program officer of the NAS National Materials and Manufacturing Board and study director for the NAS assessment of the scanner.

“As an independent not-for-profit organization, the National Academies can take a look at almost any issue within their purview without having a ‘stake in the game,’” Svedberg says.

The NAS group will be using the same model of scanner that NIST used to make its measurements — a Rapiscan Secure 1000 that was widely used to screen passengers at airports around the nation. NIST’s scanner is one of very few available machines in the country that is not either in storage or active use, says NIST researcher Lawrence Hudson, co-author of NIST’s original 2012 report.