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Security Transportation

Backscatter X-Ray Machines Easily Fooled 342

Pinckney writes "A paper by Leon Kaufman and Joseph W. Carlson in the Journal of Transportation Security asserts that x-ray backscatter machines are not very effective (PDF) even in their intended role. While carelessly placed contraband will be detected, the machines have glaring blind-spots and have difficulty distinguishing explosives from human tissue. As they write, 'It is very likely that a large (15–20 cm in diameter), irregularly-shaped, cm-thick pancake [of PETN explosive] with beveled edges, taped to the abdomen, would be invisible to this technology. ... It is also easy to see that an object such as a wire or a boxcutter blade, taped to the side of the body, or even a small gun in the same location, will be invisible.'"
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Backscatter X-Ray Machines Easily Fooled

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  • by Ismellpoop ( 1949100 ) on Saturday December 11, 2010 @03:15PM (#34524652)
    the former head of Homeland Security, Michael Chertoff helped sell them to the government and the government mandated them and removed everyone's rights.
    American anthem playing in background.
  • by mellon ( 7048 ) on Saturday December 11, 2010 @03:20PM (#34524690) Homepage

    It's highly questionable whether the machines are even capable of identifying "suspicious areas of the image." But suppose for a moment that they are. These scanners are already, in themselves, more of a safety hazard than actually flying. They have been through nowhere near the degree of rigorous safety testing and analysis that any component of an aircraft has to go through. While exposure to the intended dose of radiation for a scan may be safe (even that is debatable), the scanning process is software controlled. Imagine if the software crashes in the middle of a scan, or the scanner mechanism sticks.

    And now, suppose that it is possible to detect suspicious areas of an image and do a more thorough scan. This simply increases the safety risks of these machines. X-ray scanners? How is that exposure going to be controlled? Is testing ever going to be held to the degree of rigor required for aircraft? If not, why should we be willing to accept the risks of using these machines?

    The fact is that if we really care about people taping explosives to their stomachs, the only way to detect this is with a thorough search (a.k.a. "enhanced patdown"). If we are really that concerned about security, that is what every traveler should be subject to. And if we aren't comfortable with searching passengers like that, then we really ought to stop being such cowards and accept the quite minimal risk that someone is going to get one of these Rube Goldberg explosive devices past security and actually succeed in harming an aircraft with it (unlike the shoe-bomber and underwear bomber attempts, which did not harm either aircraft).

  • It's theater... (Score:5, Insightful)

    by sdo1 ( 213835 ) on Saturday December 11, 2010 @03:20PM (#34524698) Journal

    Not to sound like a broken record (does that phase mean anything to people or did I just show my age), but I'm not sure why this surprises anyone. It's not about security. It's about security theater. And until the TSA fundamentally changes the way they do things, it always will be.

  • by Dr. Spork ( 142693 ) on Saturday December 11, 2010 @03:24PM (#34524726)
    Why didn't the TSA test this technology first to make sure it works? I mean, it's not like cloth tape and a flattened explosive are unprecedented or amazingly cunning bits of circumvention! Why not hire 20 nerds and give them a week to figure out if they can sneak something truly dangerous through the scanner? As long as they can do so reliably, wait for the next version of the machine and test again. Only when it works should you place the order!
  • by drumcat ( 1659893 ) on Saturday December 11, 2010 @03:29PM (#34524774)
    Come on. The government? They always buy first, and maybe question later. It's your money they spend, not theirs!
  • by Mojo66 ( 1131579 ) on Saturday December 11, 2010 @03:34PM (#34524822)
    Exactly. Those machines were not installed to make flying more secure, but to make a few select people a bit more richer than they are already. This is how goverments work nowadays.
  • by meerling ( 1487879 ) on Saturday December 11, 2010 @03:37PM (#34524862)
    Terrorists don't care about reliability, look how many suicide bombers die from premature detonation.
    (Feel free to laugh at the joke, both of them, but it's real and some statistics have been published on this.)
    They are very willing to send a half dozen or more people through in the hopes that one makes it to target.
  • by Anonymous Coward on Saturday December 11, 2010 @03:57PM (#34525016)

    Precisely. The shoe bomber got through, and his bomb didn't work. Ditto the underpants bomber. Airport security failed miserably. It didn't matter.

    As for the liquid bombers, it's still debatable whether their bomb would have worked, but who cares? They never even made it as far as the airport!

    I am still waiting for the TSA to present the American people with any evidence -- even the tiniest shred of evidence -- that they have ever once in their entire history caught an actual terrorist.

  • Comment removed (Score:5, Insightful)

    by account_deleted ( 4530225 ) on Saturday December 11, 2010 @03:59PM (#34525024)
    Comment removed based on user account deletion
  • by DavidTC ( 10147 ) <slas45dxsvadiv.v ... m ['box' in gap]> on Saturday December 11, 2010 @04:02PM (#34525034) Homepage

    Yup, experts have been warning about this all year. Meanwhile, explosives detectors (you know, the ones removed from airports last year because they were too much trouble to maintain) seems to be a banned topic in the news.

    Meanwhile, we're letting utterly unchecked luggage onto the plane.

    Don't worry, we've solved that by banning wifi. Luckily, there's no other way besides wifi and by hand to detonate explosives.

    Unfortunately the TSA now has too much invested to suddenly admit it probably wasn't a good idea to stop using the more effective machines that are less invasive (they were the round swabs on luggage) replaced with the less effective machines that are more invasive.

    The TSA doesn't have to 'admit' things regardless.

    As I've suggested, the TSA should be required to operate something like this:

    There is an independent office outside the whole TSA, operated by non-TSA people. Let us all it the TSA Inspector General office.

    You show up there and present some object to wish to smuggle past TSA, or take one from them. It doesn't have to be the actual banned object, but it has to be one that would 'serve the function' of the object.

    They write down your name and what you're doing. You give them a $100 bond.

    If you manage to get that item past TSA, you then got to the IG office on the other side, and explain how you did it, and they pay you $1000 out of TSA's budget. The TSA is not allowed to know your name or any other identifying information so they can't start searching you extra. (The IG's office, OTOH, will know your name and the plane you're going to, and you won't be let on the plane, and be in rather a lot of trouble if you don't show up at their office with the stuff.)

    If you don't get it past TSA, you forfeit the bond.

    REPEAT.

    The very first thing people will do is smuggle 'razor blades'. By the thousands. Easy easy money-making scheme. There's all sorts of ways to hide very sharp things.

    At some point, the TSA will stop banning stuff they can't possibly stop. Or go broke. Or actually get to the point where only naked people get through.

    Let's call it 'privatized security testing'.

  • Re:It's theater... (Score:5, Insightful)

    by Inominate ( 412637 ) on Saturday December 11, 2010 @04:06PM (#34525068)

    It's not even theater anymore, it's about the TSA buying expensive machines to make their friends rich.

  • by Beryllium Sphere(tm) ( 193358 ) on Saturday December 11, 2010 @04:27PM (#34525184) Journal

    >not very effective (PDF) even in their intended role

    You're implicitly buying in to the claim that their intended role has something to do with safety.

    The purpose of a system is what it does. The ~$200,000 scanner purchases funnel tax money to a company which made payments to the former director of Homeland Security. They condition people to being treated like prisoners. The first was deliberate.

    They're working perfectly.

  • by bkmoore ( 1910118 ) on Saturday December 11, 2010 @04:31PM (#34525204)

    Most people don't realize that backscatter is an imaging tool and not a bomb detector. It requires a human operator to interpret the image. If the bomb is well blended into body contours, there is a high probability that the operator would miss it. If you look at the backscatter sales literature (it's on their web sites) it shows images of people with concealed knives or guns. Stuff that would also set off a metal detector.

    In my opinion, it is a little disingenuous that the TSA is using the bomb threat as the justification to switch from metal detectors to backscatter. One of the reasons that the shoe and underwear bombers failed is they weren't able to conceal a proper detonator (which contains metal), and resorted to trying jerry rig a lighted fuze detonator. So in that sense, the metal detectors did do their job. But if concealed explosives were the primary threat, then x-ray in tandem with bomb sniffing dogs or some type of actual bomb detector would be more effective. The other downside to imaging is the human operator spends hours looking at thousands of passengers. There is a good chance that the operator won't be alert enough to spot a bomb or weapon, even when it is not perfectly concealed.

  • by dgatwood ( 11270 ) on Saturday December 11, 2010 @04:32PM (#34525214) Homepage Journal

    I basically agree with you, but I'd go one step farther.

    It's highly questionable whether the machines are even capable of identifying "suspicious areas of the image." But suppose for a moment that they are.

    Suppose we live in a world of fluffy pink unicorns and candy canes. The fact that we're even posing such a hypothetical scenario is part of the problem; we shouldn't even give them the benefit of the doubt. These pieces of garbage should never have been ordered at taxpayer expense until there was consistent, demonstrable proof of their effectiveness. The safety debate shouldn't even be happening now. The safety, privacy, and medical records debates should be happening ten years from now when they finally build a machine that is effective (read "full body CT scan or MRI scan"), and these worthless, overpriced toys shouldn't even be here.

    The fact of the matter is that people described in great detail a number of fairly straightforward attack vectors for circumventing these things before the government even ordered them. The whole "body cavity" problem is so obvious that our government buying these things verges on pure comedy. And before anyone makes the irrelevant claim that you can't hide enough explosives in a body cavity to bring down a plane, I would point out that 9/11 involved 19 people. How much explosive material could you fit in 19 body cavities? If the answer is, as I suspect, "plenty", then these scanners are worthless even if they can detect explosives on the outside of your body.

    The only way to reliably detect such things is by knowing your passengers. Even enhanced patdowns are useless against organized terrorist attacks. Profiling really is the only effective means of combatting terrorism, and those who say otherwise are kidding themselves.

  • by Solandri ( 704621 ) on Saturday December 11, 2010 @04:42PM (#34525278)

    This has always puzzled me. The passengers are thoroughly inspected, but I see many airports where you can still reach (and compromise) the planes themselves quite easily.

    That's because airport security is security theater. Even with terrorism and accidents, planes are already the safest way to travel between two points. The security at the airport is just a dog and pony show to reassure fliers and give the impression that the government is "doing something about it". The effectiveness of the security measure is rather meaningless because a 50% reduction in almost-never will still be almost-never.

    In fact concern over the new scanners and pat-downs at airports is probably going to kill more people than any terrorists. People uncomfortable with the invasion of privacy may choose to drive to their destination rather than fly. And you're roughly 15-20x more likely to die from an automobile accident than from a plane crash/terrorist incident over a trip of the same distance.

  • by ElMiguel ( 117685 ) on Saturday December 11, 2010 @04:44PM (#34525296)

    surely the difference between sound and RF energy is not too hard for a TSA agent to understand.

    You overestimate how much the average person knows about science, never mind a TSA agent.

    And don't call me Shirley.

  • Comment removed (Score:4, Insightful)

    by account_deleted ( 4530225 ) on Saturday December 11, 2010 @04:58PM (#34525366)
    Comment removed based on user account deletion
  • by smilinggoat ( 443212 ) on Saturday December 11, 2010 @05:05PM (#34525404) Homepage Journal

    Adam Savage of Mythbusters walked through a backscatter with two 12" razor blades [youtube.com] and they never noticed.

  • by Reziac ( 43301 ) * on Saturday December 11, 2010 @05:14PM (#34525442) Homepage Journal

    "These scanners are already, in themselves, more of a safety hazard than actually flying. They have been through nowhere near the degree of rigorous safety testing and analysis that any component of an aircraft has to go through."

    Consider the level of testing and analysis that the *very same device* would require if it were labeled "medical equipment" rather than "airport security equipment". Consider also the site and personnel licensing required to operate one (probably akin to that required for a modern xray machine).

  • by careysub ( 976506 ) on Saturday December 11, 2010 @05:28PM (#34525522)
    And then there are the body cavity bombs that have already been used. These are more powerful and are actually easier to engineer than irregular pancake "Woochie" bombs (a special effects prosthetic maker). Only body cavity searches or medical scanners will detect these by imaging. And there are also the possibility of weapons being passed via the concourse services - is the news stand supply chain truly secure against penetration? There is a point where trying to completely eliminate one category of threat passes the point of futility - when the residual threat is dwarfed by other unaddressed ones - we are surely there now, as we are also past the point where further intrusive measures reduce risks by such tiny amounts that other considerations must take precedence.
  • by toooskies ( 1810002 ) on Saturday December 11, 2010 @05:51PM (#34525656)

    The low risk of terrorism is because while blowing up a plane with a bomb is possible, you're pretty much targeting random people. And if you're going to target random people, you may as well blow up a subway in NYC, or a professional sports game, or the security line at the airport. Same people dead, just as much fear (or more), and a lot less security than what is in our airports. Sure, a plane falling out of the sky will also cause collateral damage on the ground, but that is also very difficult to aim, so if anyone on the ground gets hurt it's again a random target. And that can happen anywhere.

    What was novel about 9/11 was using the plane as a weapon. As soon as you prevent that (i.e. assuming people want to use the plain as a missile instead of a vehicle) then you never again have more at risk than the people in the plane. And we have-- locked cockpits and aware citizenry is enough to prevent that from ever happening again.

  • by jimicus ( 737525 ) on Saturday December 11, 2010 @05:52PM (#34525664)

    Really? Who?

    I'm deadly serious, if Al Qaeda et al were anything like the threat they're supposed to be, we'd be hearing of attempted bombings every month. With regular successes.

    What we hear is of amazing cockups and attempts at blowing things up which are not only jaw-droppingly stupid, but the time it takes for anyone to spot them and say "Hang on a minute... since when did arabs ship printers to synagogues?" is also jaw-dropping.

  • by arb phd slp ( 1144717 ) on Saturday December 11, 2010 @06:51PM (#34525958) Homepage Journal

    A security measure that is not perfect can still be good. Okay it can be circumvented by a limited set of actions.

    A terrorist attack also doesn't have to be perfect to be good. Neither the shoe, underwear, nor toner-cartridge bombs went off and they still cost $billions. Unfortunately, the long-term economics of this don't favor us.

  • by kd5zex ( 1030436 ) on Saturday December 11, 2010 @07:09PM (#34526060)

    Do you think the TSA is going to make a scene every time they successfully stop a terrorist attack?

    Without a doubt.

  • by ls -la ( 937805 ) on Saturday December 11, 2010 @07:34PM (#34526198) Journal

    This obviously means that we are going to need better technology. We'll need technology that will be able to give us a full color representation of your completely nude body, but only if you're a hot chick. - Your Friendly local TSA Agent

    Even better, implement beer goggle technology into these full body scanners, so no matter how the passenger really looks, the TSA agent will never need eye bleach at the end of his or her shift.

    How about reverse beer goggles. No matter how hot the people going through the scanner are, the agents that see the scans will want to gouge their eyes out with a spoon.

  • by JWSmythe ( 446288 ) <jwsmythe@nospam.jwsmythe.com> on Saturday December 11, 2010 @07:48PM (#34526256) Homepage Journal

        Shreds of evidence are abundant. They've caught people trying to carry guns, knives, screwdrivers, and baby bottles onto airplanes. I don't know what the numbers are, but since they've confiscated several screwdrivers and half-empty soda bottles from me, I'm sure the numbers are huge.

        What you're really looking for is solid evidence. Prove that any significant number of threats have been stopped because of any new technology or methodology. The publicized cases were:

        1) Shoe bomber. Defeated by his inability to work a book of matches, and stopped by other passengers and flight crew.

        2) Underwear bomber. Defeated by his inability to acquire functional explosives. Again, he was stopped by other passengers and flight crew.

        3) Binary explosive bomber. The explosives weren't binary (to be mixed for explosion), they were pre-mixed. They never made it anywhere near an aircraft, and were possibly yet another law enforcement operation to catch those who may consider doing something by guiding them far enough to prosecute.

        So no, what you see happening in airports is security theater. It creates the illusion of security, because the common citizens have to jump through the hoops, in the name of security.

       

  • by mdarksbane ( 587589 ) on Saturday December 11, 2010 @08:33PM (#34526456)

    Indeed. Why would anyone bother sneaking a bomb through airport security when malls, stadiums, high school graduations, and even the airport security line are such easy and terrifying targets.

    The whole usefulness of attacking an airplane is to take control of a multi-million dollar man-guided missile. That's not going to happen any more, with the secure cockpit doors and passengers who aren't likely to along quietly.

  • by crovira ( 10242 ) on Saturday December 11, 2010 @11:06PM (#34527056) Homepage
    this autopsy performed on you?" Its theater. You're supposed to be lulled into a sense of complacency. This will catch only the incompetent terrorists. But given the fact that these guys are obviously not the sharpest knives in the drawer, (obviously since they've been talked into believing that there's an afterlife, that they'll be entitled to a bunch of grapes when they reach Valhalla, or wherever you go when you're no longer going anywhere, they're pretty friggin' stupid,) the system should catch all of those morons.
  • by fahlesr1 ( 1910982 ) on Sunday December 12, 2010 @12:04AM (#34527224)

    Behavioral profiling, such as what is practiced by the Israelis, is both cheaper and more effective than searching for weapons. If we adopted behavioral profiling, screened all baggage for explosives and ran passengers through the air-puff chemical sensors we'd have a system that protects travelers privacy much better, is much more effective and significantly cheaper than our current system.

    Explosives are the real threat anymore. A few terrorists wonldn't be able to take over an airplane, not now that the passengers will fight back and the cockpit doors are reinforced. Preventing passengers from bringing things like nail clippers is just asinine.

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