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New Explosive Detection Tech
cruci writes to tell us Yahoo! is reporting that a New Zealand company, Syft, has developed a new way to detect many different kinds of explosives (and their individual ingredients) in real time. Designed for what the company calls "photocopier simplicity", CEO Geoff Peck claims that the technology is ready to deploy immediately and is already deployed in some ports and hospitals. From the article: "The Voice100(TM) employs Selected Ion Flow Tube - Mass Spectrometry (SIFT-MS). While SIFT-MS has been in academic use for more than 20 years, Syft Technologies is the first company to offer a commercial instrument with the full discriminating analytical power of a laboratory-grade mass spectrometer."
If you have these exquisitly sensitive machines that can detect even a few molecules of material, aren't they by the same token super-vulnerable to being attacked by "chaffing" or overloading?
You have to look at the false positive and negative rates for detection. If you have a test that is 99.99% specific, it will still fail in practical use in an airport, as that means that 1 out of 10,000 people will come up positive. If you have a lot of people going through you will still have a big problem (London had over a million flights last year). This is the same issue as using automatic detection of terrorists – It's one thing to match/no match a known ID (e.g. biometric passport) to a person; it's another to match every passer by to every known terrorist.
Going back to chemical detection: this level of sensitivity will mean that every person runs the risk of coming up positive eventually. This amounts probably about 100,000 people in the U.S., and lots more elsewhere in the world.
Not the U.S. I think we made it adequately clear that our DHS doesn't exist to improve homeland security, rather just to scare the citizenry.
Someone had to do it.
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>The Voice100(TM) instrument's core feature is its ability to continuously detect and quantify the concentration of Volatile Organic Compounds (VOCs) in whole air.
In other words, if the bad guy's dumb enough to make his explosive before passing through the screening station, he gets picked up.
But since hydrogen peroxide isn't an organic compound, Abdul walks up to the scanner and it says "Nothing to see here. Move along."
And since acetone is a VOC, when Mohammed walks up to the scanner, the scanner screams bloody murder... which would be fine, except that it also probably screams bloody murder for every woman with a bottle of nail polish remover in her purse. So Mohammed gets told to move along, too.
*blam*
Airlines are like democracies: We have to destroy them to save them.
We should be detecting bombers not bombs. Bombs form a nearly endless variety. Bombers are an easier class of object to detect, I believe. The fact that the bombers try to hide the bombs on their person or in their carry on luggage suggests they they themselves don't fear the system's scruitiny. In the old days they had to figure out ways of getting the bomb on the aircraft without them being anywhere near it. How times have changed.
Semtex doesn't explode when you burn it.
I have no problem with his argument, except from what I have read, the bad guys were going to mix the chemicals on the ground AFTER they had passed the initial security checkpoint but before they had boarded the plane. For example in the bathroom next to the Duty Free shop. Therefore his whole argument doesn't really hold up. They could mix the chemicals in the bathroom in glass bottles, and then transfer them into water bottles (or was it sports drink bottles?) and then detonate them on the planes. Otherwise it is a good critique. It just goes to show you that people who want to blow up planes aren't complete idiots.
I work in a chemistry lab where we regularly synthesis small quantities of explosives. Last weekend I took a flight and (very stupidly) wore the same shoes that I normally wear to work. They swabbed my shoes down and passed me through without a second glance. It didn't occur to me until after I was through security that there was surely some trace amount of explosives on my shoes that should have been detectable. Upon further reflection I realized that the detector was probably only set to look for a few certain common explosives, and the explosive compounds that we work with in my lab are relatively esoteric.
I think that the very narrow specificity of these machines is a major problem. You might be able to detect the 20 most common explosives, but it would be trivially easy for any competent organic chemist to come up with a new explosive that the detector wouldn't be looking for. Perhaps the detectors that we have now look for nitroglycerin, but what about nitroglycerin with an extra methyl group hung off the end of the carbon chain? Or an ethyl group? Or an isopropyl group? What if instead of ammonium nitrate you used butyl-ammonium nitrate? Or butyl ammonium with some other, less common oxidizer like permanganate/perchlorate/whatever? Do you see my point? You could make a slight modification to almost any existing explosive and render it undetectable to these bomb scanners, because the scanners only look for things that they have been specifically trained to look for. They have no capability to actually examine the structure of a molecule and judge whether it's explosive or not. It's kind of like using a "knife detector" that has been set to look for the most common brands of knifes, when in fact you could sharpen almost anything into a knife with a little effort.
Don't forget the whole accusation is based on Pakistani intelligence interrogations - yes they do have an interested in reporting there are terrorist attacks planned, yes they do torture, and yes that does sparkle the imagination of the tortured. There is, from what little information there was in the press releases, the serious possibility this whole panic is based on nothing but rumor and the ideas of someone who saw Die Hard With A Vengeance and learned there are liquids that become explosive when you mix them.
Many of you will probably already know that the timing of the "bust" was carefully planned between Bush and Blair to coincide with a vote of no confidence planned against Blair on the same day.
In a very similar way, Syrian intelligence has been known to produce extremely convenient intelligence. They were the guys who said Al-Zarqawi was in the leader of Al-Qaeda in Iraq - and sole proof of the Saddam-Terrorism connection - in the beginning of 2003, when Al-Zarqawi was neither a leader, nor an Al-Qaeda member, nor in Iraq.
The above is not off topic, but means there is no reason to be surprised when the whole story is implausible. It also means there is no reason to be surprised that Scotland Yard and all involved intelligence services, despite the knowledge of their weapon experts, fail to announce the plan was nonsensical.
blow your mind already