ABC: U.S. Airport Full Body Scanners Too Unreliable to Use, Germany Says

Discussion in 'Aviation Passenger Security in the USA' started by Mike, Sep 2, 2011.

  1. Wimpie

    Wimpie Original Member

    This is not true. The passive MMW scanners do not have the necessary resolution to detect things. This is why TSA has not bought any. The images leaked from the courthouse in Florida last year were from this technology;
    http://www.brijot.com/products/gen2

    The youtube video panning the scanners in Germany from about a year ago:
    http://www.youtube.com/watch?v=idICUSiGcqo
    shows how hopeless the passive scanners are.

    Recently, Germany rejected the active ones (L3 with ATD) as worthless as well, with >50% false positives.

    CLEARLY, this is the wrong technology for detecting explosives.
     
    barbell likes this.
  2. Mike

    Mike Founding Member Coach

    I said workable concept, not a successful product. If people quit working on things because the early prototypes and products didn't meet people's ultimate objectives, nothing would ever be developed. We'd still be burning whale oil at night.

    Shifting the discussion to detecting is explosives is a red herring on your part (as well as a dumb propaganda move by TSA).
     
  3. nachtnebel

    nachtnebel Original Member

    As an owner of a .45-70, at 405 gr, this is a graphic description of a huge drop-off in potential health risk, that both you and RadioGirl describe. So a cellphone would actually pose more risk than a mmw....since you're holding it up to your head, if you don't use blue tooth.
     
  4. Mike

    Mike Founding Member Coach

    As an owner of a .45-70 handgun with a hair trigger (Thomson Center), I'd strongly suggest that defeatists not get in my way. I might mistake them for buffalo.
     
  5. exbayern

    exbayern Original Member

    Are you sure about that? There are a lot of issues surrounding this, and the final report is not even released yet.

    Apologies for the horrid source but this is the best I can find on short notice with little time. The Bild is seen as a sort of tabloid for the common masses but I cannot find a better source at the moment (most likely because the final report has not been released)

    http://www.bild.de/politik/inland/nacktscanner/aus-fuer-nacktscanner-19686366.bild.html

    Here we finally see some figures.

    809,000 passengers were voluntarily screened between 27 September 2010 and 31 July 2011. Of these 54 procent had a false alarm. 31 percent of the total passengers scanned were given a green light as the machines found nothing.

    So 31 percent of 809,000 passengers were scanned with no further check needed. Maths is not my strong suit, but that means that 69 percent of the 809,000 passengers scanned DID require a physical check, and of those 69 percent, 54 percent had no further findings.

    Disappointing: the alarm rate could only be resolved with a follow up hand search. But the expensive hand checks were to be replaced with these machines costing between 110,000 and 130,000 Euros.
    
    The article goes on to discuss 'back to the lab' and how the German federal police has told L3 that they need to look at improvements before the machines will be considered again.
     
  6. barbell

    barbell Coach Coach

    The big elephant in the room is how do we know that those 31% cleared as needing no further hand check are truly "clear". Yeah, of course no planes blew up over Germany. In spite of TSA, no planes are blowing up over the US, either. The point is, in a test like this, we have no idea that the 31% given the "all clear" were actually clear.

    So, as exbayern correctly points out we either have a 69% fail rate that actually increases the expensive hand check these machines were supposed to eliminate, or we have a 31% fail rate where we don't know conclusively that those people truly were "clean."

    Either way, it's obvious that these machines are nothing more than expensive, shiny junk.
     
  7. exbayern

    exbayern Original Member

    Apologies in advance as I am trying not to be overly political here and am trying to remain diplomatic, but I strongly disagree that all it will take is tweaking of these machines to have them implemented in Germany.

    This on the day that Teflon Angie has earned another dent in her armour... Remember, we have over 70 years of collective history which motivates us and causes us to review our collective moral compass every now and again. This is the country which permits householders to grey out their property on Google Streetview (and more than a quarter million have done so - thanks in large part to Naked Guy Climbing into Trunk Whilst Dog Watches Nonchalantly, who raised the awareness of privacy issues). This is the country where the Pirate Party (who received almost a million votes in the last election) regularly stages naked campaigns at airports to raise awareness of their platform of privacy, anti-surveillance, and civil rights. This is the country which has faced airline terror for decades, long before it became the topic of daily conversation in America.

    And perhaps most importantly, this is the country which is starting to question how much to help its friends, and how much it can afford to help its friends. Paying to keep our southern neighbours afloat hurts us all, and doing the bidding of a friend which may violate our civil rights, violate our Basic Law, and cost us a significant financial amount with possible little tangible return is not an option that many will support. And when the topic of helping friends arises, all one has to do is whisper 'Kunduz' and our most recent shame forces us again to consult our moral compass.

    I am not patriotic, and am willing to admit that we have hurt so many people in so many ways over the past century. I don't think that Germany is superior to others; I just believe that we have made so many painful and costly mistakes that we are being extra cautious to avoid making more. And when it comes to surveillance and privacy rights, we only need to think back 22 years to recall what that did to us as individuals and as a country.

    Of course, I may just be the eternal optimist, and may find that in a few months we bow to the pressure , violate our Basic Law again, and install L3 scanners in every airport in Germany. :(
     
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  8. Bungnoid

    Bungnoid Original Member

    I'm just responding to the language in the story: "Test of full-body scanners: Effective, but not yet ready for nation-wide rollout" [bolding mine]. So they are not quite ready for implementation because they are fooled by sweaty and folded clothing. But surely the technology will be improved at some point in the future to correct this deficiency. I'll guess that it won't take too long for L3 to come up with a solution. Based on the article, I don't see any impediment to future implementation once these issues are addressed. There was no mention of any other issues besides the false positive rate--for example, privacy objections.
     
  9. exbayern

    exbayern Original Member

    And you are missing critical pieces of information by referring to one short press release. I have read the articles for over a year now (and posted many of them), as well as been quite involved in the debates and discussions about privacy and surveillance and personal rights.

    Reading one short press release, as an outsider, not following the daily news on the subject, you won't necessarily understand all the issues.

    Even if the EU does eventually create the framework to permit countries to use the scanners, countries decide for themselves what they will do.
     
  10. nachtnebel

    nachtnebel Original Member

    A 45-70 in a handgun? You, sir, are a glutton for punishment. I made the mistake of agreeing to a session with an Israeli desert eagle in 50AE; d#mned unpleasant.

    Technically, ATR is probably against the 4th; practically, if the false positives are somewhere in the ballpark of wtmd, I can live with it. If the machine gives off false positives and or alarms on common items like hygiene stuff, it is DOA.
    Don't be feeling our crotches because your machine is sh!tty."
    On a tangent, I'm waiting for a flight now, and over at the bookstore I can see a sign that says "Men's Interests". Strikes me as funny. I wonder if it is located next to the Women's section.
     
  11. exbayern

    exbayern Original Member

    Interesting point. The test in Germany was entirely voluntary. Would someone wearing sanitary items or incontinence items etc volunteer to go through a scanner, and run a rather strong risk of having someone become aware of those items?

    Assuming that the number of volunteers wearing such items was low, then that further skews the results.
     
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  12. nachtnebel

    nachtnebel Original Member

    I think we'll find out soon.
     
  13. Mike

    Mike Founding Member Coach

    With a 16" compensated barrel it's not too bad off a bench rest. It's a single shot with a veerrrrry light trigger, so it's not a carry gun.

    Someone did make a 4- or 5-shot .45-70 revolver 15-20 years ago. I don't think I could stomach that. I used to pre-bandage my hand before I'd put on the shooting gloves for my .44 mag. I finally just started loading light (800 fps instead of 1400). I like the gun, not the effect in either direction.
     
  14. RadioGirl

    RadioGirl Original Member

    Wow, a Girl goes away for a long weekend and you guys work overtime. :eek: (I'm too tired to do numbers tonight. Go to The Other Place and read up where I've done all this before.) But anyway, here we go again :

    First, I'm going to let you in on the really scary part. ;) Everything in the universe emits radio waves. Really. Look up black body radiation. Radioastronomy studies the universe by detecting the faint radio signals emitted by stars, and the even more extraordinarily faint radio signals emitted by dust and gases in outer space. You, sitting right there in front of your computer, are emitting radio waves. Yeah, you. That's what the passive MMW devices detect. The table you're sitting at, and the chair you're sitting on, are emitting radio waves.

    But these levels are many orders of magnitude (thousands or millions or billions of times fainter) than the power levels from small handheld radio devices like keyless entry or the WiFi in your laptop or the Bluetooth headset, which are in turn, many orders of magnitude smaller (thousands or millions of times fainter) than high powered radio systems like TV broadcasting or military radar or (up at the top end of the power scale) the pain rays some have mentioned.
    AM/FM radio and television receivers work by generating (in the electronics) a known frequency component (local oscillator) and, in essence, subtracting it from the received (time-varying) frequency signal to get the "original" (baseband) signal. The generation of the known frequency component can leak and be detected, but as it's not connected to the antenna, it doesn't get transmitted as efficiently and so appears at a very low level. Yes, radar detector detectors work by listening for that local oscillator signature.

    A candle flame emits light. A 100 W bulb emits light. Car headlights emit light. High-powered search beams (the ones they wave in the air at night for Hollywood openings) emit light. The Sun emits light. If you stare into a high-power search beam or the Sun you'll damage your eyes. Sit all evening at a candlelit table, no damage. Even though you're much closer to the candle than to the Sun, the difference in power level is a critical distinction.

    Bottom line: the power levels emitted by "radio emitters" - including you - vary widely, and you can't just lump them all in together. To say that the MMW might be dangerous because it emits the same kind of energy as "pain rays" is like saying you can't have a lit candle on the table because a search beam is dangerous to look at.
    WTMD uses coils which produce a magnetic field which is disturbed by metal passing through it. It isn't a radio transmitter in the sense that a cell phone or a WiFi or a MMW is a radio transmitter.
    I understand that this technology is unknown, and therefore a bit frightening, to many people. But consider that the keyless entry keyfob in your pocket also emits radio waves at very low levels. Do people worry that their keyfob might someday go out of calibration and burn their leg? No, of course not, because to go from the power level necessary for its purpose to the power level necessary to burn flesh is not an increase of 3% or 10% or even 50%, it's an increase of perhaps a million fold. Things just don't go out of calibration by that magnitude.
    You raise some interesting points and I understand why people might be concerned, but to be honest I took those into account in my (numerical) analyses over at That Other Place.

    In terms of "barriers" or "blockage", I'm going to estimate that most of us spend more time outside than we would spend in airport scanners. Where I live, it takes longer to walk across the parking lot to the terminal than it takes to do a MMW scan. Whenever you are outside you are being exposed to radio energy from television and radio broadcasting, satellites, overflying aircraft, cell phone towers and (a surprising large number of) other commercial radio transmitters with nothing between you and the energy but your clothes. Gojirasan is right that police radar frequencies go through glass without much loss (see below). And the auto doors at the supermarket are aiming the radio energy straight at you from, what, maybe 6 or 10 feet away, not miles, with nothing between you and it but your clothes. People hold a cell phone up to their head for long periods of time, with nothing at all between the transmitter and skin. You may be using WiFi right now, and some of the energy from both the access point and your computer are hitting your body, including uncovered face, hands, etc.

    Secondly, what you are referring to as "diffusion" is called free space attenuation. It is based on the fact that the radio energy drops off as the square of the distance. If you are twice as far from the television transmitter as I am, you are being exposed to 1/4 the energy I am. If 10 times the distance, then 1/100 of the energy. This is not theory; it is provable from straightforward closed-form mathematics. (If you're behind a hill or building, there is some additional loss of energy, but not as much as you might think.) So the comparison goes like this: (a) what is the emitted energy at the transmitter? (b) how far away is the object from the transmitter, and what is the loss associated with that distance? (c) what additional losses (terrain, going through glass, etc) are relevant? The losses are then subtracted from the initial transmitted energy to determine the energy level at the object (a human body, in this case).

    A good analysis (and I do good analyses) also takes into account the directivity of the transmitter. Again, an analogy is useful. A candle or a 100 W bulb are (roughly) omnidirectional - energy goes in all directions - while a car headlight and those search lights are directional - most of the energy is aimed in one direction although some is visible from the side. TV towers and (most) WiFi access points are omnidirectional - signals go everywhere - while radars and auto door openers are directional - most (but by no means all) of the energy is aimed in one direction, but lower levels are emitted in the other directions. The degree to which a transmitter is directional is added to the analysis in the paragraph above.

    Furthermore, there is an analysis of how the received energy at the body is distributed over the surface of the body. Energy concentrated in a small area is more significant than energy spread out over the whole body. So the final number is in the units of power per unit area, for example, Watts per square centimeter.

    You describe the MMW as "beams shot directly at its body in all directions over its entire surface at the exact same time" but in fact the MMW works by scanning a single small beam of energy back and forth and up and down in a raster-type scan. Imagine studying the Venus de Milo with a small flashlight in an otherwise pitch dark room. If the whole body were illuminated at once, the detectors wouldn't be able to determine what bit had reflected from which part of the body. The scanner goes over each part of your body and the receiver monitors the reflected energy from that point, building up an image pixel by pixel. So in fact each part of your body is only briefly illuminated.

    You also dwell on the fact that the person being exposed is in an enclosed space but if the radio energy is going in a straight line from the transmitter to your body (and in this case it is), it doesn't matter what is behind or around your body. Yes, I suppose the energy could bounce off the walls and hit you again, but by then it has travelled a longer distance and so lost more energy before it hits you a second time. Would you worry more about using a cell phone in a car than outdoors, or about using WiFi in a small room rather than the open air.

    In the analysis that I did in the Other Place, I used the power levels filed with the FCC (which are consistent with other information I have from friends in the industry who have developed scanners used in the manufacturing industry, and from peer-reviewed papers in the field). I took into account the rather short distance between the MMW transmitter and the body being scanned, which allows a very accurate estimate of the free space attenuation, and I didn't account for any other losses due to additional barriers. I took into account the fact that the beam is focused on a spot on the body as it scans back and forth. After all that, my assessment is that the power per square centimeter as measured on the body is roughly 1/100,000 of that due to a cell phone. It is well below that from a automatic door opener at the supermarket, even after accounting for the difference in distance.

    I'm not saying MMW = safe. I don't have the biology expertise to say that. I'm just saying that the energy - as compared apples and apples - is much lower than that from other radio devices in common use. You can draw your own conclusions.
    With respect - and I do respect your opinions :) - to insist that the government spend money on long-term studies of the health effects of MMW even when, by comparison to other, well-known technologies the levels are extremely low is the same reasoning as"we have to confiscate your water and shampoo because there is a risk that they might be explosives."

    OBLIGATORY DISCLAIMER: I object to the NoS - whether MMW or x-ray - on 4th amendment grounds. I am horrified by the cost of the damn things. I despair at the visual images of Americans standing in a position of surrender to their government. I am suspicious that the government is using them as a dragnet for drugs and currency. They are slow, and as the main topic of this thread shows, they are ineffective. They lead to unacceptable levels of abuse of people with prostheses, sanitary items or medical devices. I am deeply concerned about the risk of having one's possessions ransacked while standing in the surrender position. The x-ray version is definitely of concern from a health POV. In short, we have a great many reasons for opposing the deployment of this technology. But let's not stir up fear just because we don't understand the technology - the TSA does too much of that already. :(
     
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  15. exbayern

    exbayern Original Member

    No new body scanners at German airports (from a somewhat better source, the local Hamburg paper)
    http://www.abendblatt.de/politik/de...-Koerperscanner-auf-deutschen-Flughaefen.html

    After the end of the apparently unsuccessful test ended at HAM, no scanners will appear at German airports. That was the decision of Interior Minister Hans-Peter Friedrich after the results of the ten month test phase of two machines in Fuhlsbüttel.

    The article goes on to discuss how it is too early to implement the scanners, and the significant false alarms and further follow up seraches required as a result.

    When they will reappear at German airports in test and implemented is open.

    And from die Welt online http://www.welt.de/print/die_welt/p...rperscanner-scheitern-an-Schweissflecken.html

    More than every second passenger had a false alarm. Simple pleats defeated the 120,000 euro machines.

    Considering that the headline is about how sweat stains defeated the machines, the tone continues to be mocking these useless, expensive toys.
     
  16. Mike

    Mike Founding Member Coach

    Unfortunately the tone in U.S. newspapers is "rah, rah, rah", with AGITPROP pushing out dozens of articles full of spoon-fed drivel every time one of the new, "less-intrusive" scanners is installed at another airport. I've seen a total of 3 Google hits (ABC & two affiliates) reporting on the German experience with them.
     
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  17. Lisa Simeone

    Lisa Simeone Original Member

    Indeed. This is the perennial problem. And it won't be solved by any technology, any equipment, no matter how shiny and new.

    More to the point, all this crap is just further refinement on the violation of our rights. I won't step into any frigging machine. The walk-through metal detector is as far as I will go. If these other things start showing up at courthouses, malls, restaurants, etc., then I say bye-bye to jury duty, shopping, dining out, etc. I won't put up with this sh*t.
     
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  18. Bungnoid

    Bungnoid Original Member

  19. Mike

    Mike Founding Member Coach

    I wouldn't even go to a mall or restaurant that used WTMD.
     
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  20. Lisa Simeone

    Lisa Simeone Original Member

    Good point. Ditto. I was still thinking airports, if the TSA's reign of molestation ever ends, and courthouses, where WTMD are pretty standard. (By the way, speaking of the latter, one lawyer somewhere in the country, can't remember where, will have to comb my files, refused to go through a Chertoffomizer at his courthouse, so he couldn't do his job, so he had to appeal to the judge who was waiting for him in the courtroom, etc. etc. This guy filed suit.)
     

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