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Can Imaging Technologies Save Us From Terrorists?

Posted by timothy on from the trust-shorter-answers-more dept.

itwbennett writes "In the aftermath of the failed Christmas Day terrorist attack, full body scanning technologies such as millimeter wave and backscatter are regaining popularity, writes blogger Steven J. Vaughan-Nichols in a recent post. But, he asks, do they really work? The TSA seems to think so. It has just issued a contract to purchase more millimeter wave scanners from L3 Communications. Michael Chertoff, the former homeland security secretary, told the New York Times that if these scanners had been in place, they would have caught the would-be bomber. Ben Wallace, the Conservative Member of Parliament in the United Kingdom, disagrees, saying that the technologies can't detect the kind of low-density explosive that the would-be terrorist tried to use on December 25th."

4 of 480 comments (clear)

  1. On a related note. . . by Anonymous Coward · · Score: 5, Informative

    New scanners break child porn laws

    The rapid introduction of full body scanners at British airports threatens to breach child protection laws which ban the creation of indecent images of children, the Guardian has learned.

    Privacy campaigners claim the images created by the machines are so graphic they amount to "virtual strip-searching" and have called for safeguards to protect the privacy of passengers involved.

    Ministers now face having to exempt under 18s from the scans or face the delays of introducing new legislation to ensure airport security staff do not commit offences under child pornography laws.

  2. Re:Just wait... by willy_me · · Score: 4, Informative

    As soon as these scanners are deployed terrorists will simply start to carry the explosives in an internal cavity. 80g of explosives - the amount used on the 25th - only has a volume of 36x36x36 mm^3. There are plenty of places where this could be hidden - just look at the drug mules..

    So you will still need to be searched, even if you are travelling in the nude. But at least the searches would take less time.

  3. Re:RTFA by profplump · · Score: 4, Informative

    Radiation in general isn't the problem. There's some evidence that millimeter wave radiation in particular can un-zip DNA, even at its low energy, due to resonant effects.

    http://www.technologyreview.com/blog/arxiv/24331/

    Now it's not yet clear *how* damaging regular exposure to a millimeter wave scan would be -- millimeter waves already exist in the natural environment and haven't killed us all yet -- so it's entirely possible that there is no real danger. But I'd like to see some of the billions spent on these machines used to verify that before we get too far along.

  4. Re:They are another layer by Anonymous Coward · · Score: 4, Informative

    Hi, original AC here.

    Active systems, as they exist now, are portal only. Thus there is only the exposure to several seconds of either millimeter-wave or x-ray radiation while in the portal. Also, the operators have no control over the emitted power. It is constant, person to person. The SNR of active systems is incredible even at such low radiation levels; increasing it would do nothing useful.

    Regarding your comment of crowd scanning; this is how some passive systems work, but (currently) no active systems. Passive, i.e., picture a CCD. Visible or IR currently, right? Well, imagine a millimeter-wave/terahertz one. Still passive, but can see through clothing at decreased spatial resolution (diffraction limited). No harm done by standing in front of a passive sensor all day long.

    About the transmission/storage of images: That is determined by the final system manufacturer and the TSA. I work only on the imaging hardware and initial display. I tend to agree with you, however.

    Why millimeter-wave over IR? IR cannot penetrate clothing as well as you think. And IR sensors are no more 'safe' than passive millimeter-wave/terahertz sensors: both are 100% safe.