Backscatter X-Ray Technology
Backscatter X-ray technology is a method of using X rays to see inside objects. The science is complicated, but the upshot is that you can see people naked:
The application of this new x-ray technology to airport screening uses high energy x-rays that are more likely to scatter than penetrate materials as compared to lower-energy x-rays used in medical applications. Although this type of x-ray is said to be harmless it can move through other materials, such as clothing.
A passenger is scanned by rastering or moving a single high energy x-ray beam rapidly over their form. The signal strength of detected backscattered x-rays from a known position then allows a highly realistic image to be reconstructed. Since only Compton scattered x-rays are used, the registered image is mainly that of the surface of the object/person being imaged. In the case of airline passenger screening it is her nude form. The image resolution of the technology is high, so details of the human form of airline passengers present privacy challenges.
EPIC’s “Spotlight on Security” page is an excellent resource on this issue.
The TSA has recently announced a proposal to use these machines to screen airport passengers.
I’m not impressed with this security trade-off. Yes, backscatter X-ray machines might be able to detect things that conventional screening might miss. But I already think we’re spending too much effort screening airplane passengers at the expense of screening luggage and airport employees…to say nothing of the money we should be spending on non-airport security.
On the other side, these machines are expensive and the technology is incredibly intrusive. I don’t think that people should be subjected to strip searches before they board airplanes. And I believe that most people would be appalled by the prospect of security screeners seeing them naked.
I believe that there will be a groundswell of popular opposition to this idea. Aside from the usual list of pro-privacy and pro-liberty groups, I expect fundamentalist Christian groups to be appalled by this technology. I think we can get a bevy of supermodels to speak out against the invasiveness of the search.