So in May of this year, Susan Collins, the ranking member of the Senate's Homeland Security Committee, authored a Senate bill provision that would require an independent study of the backscatter machines. A truly independent study. And, late last night, Collins made an announcement: The TSA has agreed to contract with the National Academy of Sciences to study the health effects of the radiation delivered by the backscatter machines. Yes. YES. The agency, Collins said in a statement, "has heeded my call to commission an independent examination into the possible health risks travelers and TSA employees may face during airport screenings."

In other words: We might finally get a (reasonably) definitive and science-driven answer to the nagging question of airport scanner safety. According to the DHS contracting notice dug up by Politico Pro:

The Department of Homeland Security, Office of Procurement Operations (OPO), Washington, DC intends to award a sole source contract to the National Academy of Sciences pursuant to FAR 6.302-1 to convene a committee to review previous studies as well as current processes used by DHS and equipment manufacturers to estimate radiation exposure resulting from backscatter x-ray advanced imaging technology (AIT) systems used in screening air travelers and provide a report with findings and recommendations on: (1) whether exposures comply with applicable health and safety standards for public and occupational exposures to ionizing radiation, and (2) whether system design (e.g., safety interlocks), operating procedures, and maintenance procedures are appropriate to prevent over exposures of travelers and operators to ionizing radiation. This study will not address legal, cultural, or privacy implications of this technology.

It's worth repeating: This study will not address legal, cultural, or privacy implications of this technology. The privacy concerns -- the considerations that have been even more controversial than the machines' health effects -- won't be studied here. That's another question, for another day. But the fact that there will be a health-focused study, and the fact that it will be run by the NAS, is good news -- for science, for straight talk, and for anyone who has walked through an airport body scanner and wondered, "Is this really safe?"

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