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False Positives on Explosives
I keep reading and hearing about false positives on explosives. How do you avoid them? I heard that even lotion and toothpaste can alarm the test. I guess you can ask them for new gloves from the box and a new swab but then you get branded as "difficult" for even thinking of asking.
Seriously, if the current testing method keeps giving false results, shouldn't they find a better method that is more accurate? Could the current methods be also giving false negatives?! In the end, I guess it doesn't really matter, it's all security theatre. But what if I don't want to play along? |
Sometimes they run the test by picking "random" people out of line. If you time it right you could avoid it that way.
There's not really a good way to avoid a false positive. The test alarms on at least these things:
Keep in mind, the test isn't directly for explosives. It's for a class of chemicals that are components of explosive compounds and also components of many other things... So aside from the contamination and calibration issues - and any unexplained false positives - the test works as designed. That's why a positive on the test leads to a pat down. The pat down is supposed to clear the alarm by "proving" there are no actual explosives on the person. One of the problems is that many TSOs confuse a positive test with a confirmation of explosives. That was apparently never the purpose of the test. It was supposedly designed as a first alert that there may be something dangerous happening. Yeah, that's not a very good design... but there's supposedly nothing better available. |
Avoid the firing range?
I travel to the USA regularly for target shooting competitions... so lots of my clothes/gear would be well contaminated by residue from the smokeless propellants I use.. especially my range bag which has done double duty as my carry on... never had a problem. I have even travelled with a powder thrower.. had THAT in my carry on (it's an expensive item and not terribly rugged) and presumably because it was an unusual looking thing they took it out of the bag and wiped the swab around the interior of the powder reservoir.... NO result... So.. from that experience.. I wouldn't be real concerned about flying after being at the range! :D |
Originally Posted by MDtR-Chicago
(Post 16209041)
Sometimes they run the test by picking "random" people out of line. If you time it right you could avoid it that way.
There's not really a good way to avoid a false positive. The test alarms on at least these things:
Keep in mind, the test isn't directly for explosives. It's for a class of chemicals that are components of explosive compounds and also components of many other things... So aside from the contamination and calibration issues - and any unexplained false positives - the test works as designed. That's why a positive on the test leads to a pat down. The pat down is supposed to clear the alarm by "proving" there are no actual explosives on the person. One of the problems is that many TSOs confuse a positive test with a confirmation of explosives. That was apparently never the purpose of the test. It was supposedly designed as a first alert that there may be something dangerous happening. Yeah, that's not a very good design... but there's supposedly nothing better available. Nitrogen is the gas that forms the largest percentage of the air we breath. For this reason and others, nitrates are absolutely everywhere. The TSA goons are certifiably mad. Whatever these fruit pies are doing, there's no way that their real purpose could be "searching for explosives." No one is that stupid. |
I had a camera bag that alerted at DFW. I know for a fact that the bag had not been in contact with anything remotely dangerous.
I have been told that the ETD equipment has a high false positive rate like every other piece of equipment that TSA has purchased. TSA's answer to security is like using an A380 to move one person across town. The problem is Pistole's Perverts and the processes TSA has in place to screen 2 million people each day who present almost zero threat to commercial aviation all while allowing every airport worker to bypass any meaningful screening. |
Originally Posted by trooper
(Post 16209394)
Avoid the firing range?
I travel to the USA regularly for target shooting competitions... so lots of my clothes/gear would be well contaminated by residue from the smokeless propellants I use.. especially my range bag which has done double duty as my carry on... never had a problem. I have even travelled with a powder thrower.. had THAT in my carry on (it's an expensive item and not terribly rugged) and presumably because it was an unusual looking thing they took it out of the bag and wiped the swab around the interior of the powder reservoir.... NO result... So.. from that experience.. I wouldn't be real concerned about flying after being at the range! :D So between the percentage of false negatives and the percentage of false positives, is there any percentage left over for accurate results from this equipment? Is it ever right? |
Originally Posted by ElizabethConley
(Post 16210072)
So between the percentage of false negatives and the percentage of false positives, is there any percentage left over for accurate results from this equipment? Is it ever right?
If they truly are accurate then how could that information negatively impact the screening process? The only negative would be if the false positive rate is high. The we have the problem of the highly trained TSA workforce having to learn how to push a button. I'm sure teaching that is a significant issue. |
Originally Posted by Boggie Dog
(Post 16210189)
I would like to see Congress force TSA to release records detailing the accuracy of their various machines.If they truly are accurate then how could that information negatively impact the screening process? The only negative would be if the false positive rate is high.
The we have the problem of the highly trained TSA workforce having to learn how to push a button. I'm sure teaching that is a significant issue. I would like to see congress totally disband the TSA and replace it with a fresh organization. Fresh name, fresh mission statement, fresh leadership and fresh employees. The new organization should be 1/4 the size of the TSA, or even smaller. It's job should be limited to exercising administrative oversight of Transportation Security. Does Congress have any power whatsoever over the TSA? If so, why haven't they exercised this power? Beyond using a few harsh words, Congress has done nothing to the TSA. Are the harsh words simply a show to fool their constituents into thinking they care, or are the congressmen/women truly powerless? What's going on? Why no action? I don't get it. |
"What's going on? Why no action? I don't get it."
Makes two of us. Chaffetz, Mica Ron Paul and some others talk but nothing gets done. The Alaska State Rep. took the trouble to go to Washington and testify and then nothing comes from it and she apaparently is doing anymore in Alaska. She had the Dem. Gov. and at least one Dem Senator and I'm sure others that supported her. I'll bet if they threatened to work against O's re-election it ight get some action. |
Originally Posted by ElizabethConley
(Post 16210236)
Does Congress have any power whatsoever over the TSA?
Originally Posted by ElizabethConley
(Post 16210236)
If so, why haven't they exercised this power?
Originally Posted by ElizabethConley
(Post 16210236)
Beyond using a few harsh words, Congress has done nothing to the TSA. Are the harsh words simply a show to fool their constituents into thinking they care,
Originally Posted by ElizabethConley
(Post 16210236)
or are the congressmen/women truly powerless?
Originally Posted by ElizabethConley
(Post 16210236)
What's going on? Why no action? I don't get it.
|
Originally Posted by trooper
(Post 16209394)
So.. from that experience.. I wouldn't be real concerned about flying after being at the range! :D
|
I've been thinking that the explosives swab may be an attempt to spread the needle-in-haystack search across the broader population, rather than the ethnic populations in which terrorists are a small but notable subset.
Just a theory. |
Originally Posted by I'd Rather Walk
(Post 16210536)
"What's going on? Why no action? I don't get it."
Makes two of us. Chaffetz, Mica Ron Paul and some others talk but nothing gets done. The Alaska State Rep. took the trouble to go to Washington and testify and then nothing comes from it and she apaparently is doing anymore in Alaska. She had the Dem. Gov. and at least one Dem Senator and I'm sure others that supported her. I'll bet if they threatened to work against O's re-election it ight get some action. That's the one thing that I don't understand. We are told that thing will be changed for the better, but we continue to be harassed by TSA. :( |
better a false positive than a false negative!....
a false negayive could ruin the day for a lot of people! |
Originally Posted by clacko
(Post 16211457)
better a false positive than a false negative!
|
Originally Posted by trooper
(Post 16209394)
Avoid the firing range?
I travel to the USA regularly for target shooting competitions... so lots of my clothes/gear would be well contaminated by residue from the smokeless propellants I use.. especially my range bag which has done double duty as my carry on... never had a problem. I have even travelled with a powder thrower.. had THAT in my carry on (it's an expensive item and not terribly rugged) and presumably because it was an unusual looking thing they took it out of the bag and wiped the swab around the interior of the powder reservoir.... NO result... So.. from that experience.. I wouldn't be real concerned about flying after being at the range! :D do you use smokeless or black powder? :) |
Originally Posted by Caradoc
(Post 16210615)
And yet standing downwind of a fireworks show was enough to trigger the "puffer" machines in ATL before they were mothballed.
Golfing! In Phoenix! Must be a terrorist... |
Originally Posted by barbell
(Post 16211835)
Golfing was a high offense at PHX during this same period.
Golfing! In Phoenix! Must be a terrorist... |
A former colleague had his shoes confiscated by TSA after they tested positive. This was despite TSA's running them through the x-ray feeling them, etc. Said former colleague owned a farm and walked past a fertilizer spreader on the way to get in his car.
TSA refused to clear the shoes based solely on the ETD. He arrived at the corporate meeting shoeless. |
Originally Posted by clacko
(Post 16211457)
better a false positive than a false negative!....
a false negayive could ruin the day for a lot of people! Has there EVER been a documented case where the TSA has detected explosives in passenger luggage? You would think the TSA would make a big deal about this. Have they? |
Originally Posted by fishferbrains
(Post 16212675)
Let's turn this around for a moment:
Has there EVER been a documented case where the TSA has detected explosives in passenger luggage? You would think the TSA would make a big deal about this. Have they? The fellow who arrived at his meeting shoeless did have a great story to tell, though. That is priceless PR for our side.... |
Originally Posted by barbell
(Post 16211835)
Golfing was a high offense at PHX during this same period.
Golfing! In Phoenix! Must be a terrorist... When I got the secondary patdown in the private room (I know, shouldn't have allowed that) the machine kept alarming and the TSO made note of the fact that the machine was alarming way too much. When I commented on the fact that it appeared that they had some equipment issues he said, "It's all a bunch of crap." That's a direct quote. better a false positive than a false negative!.... a false negayive could ruin the day for a lot of people! I have several flights coming up in the next week out of SAN. It disturbs me greatly that my need to fly brands me as a suspect in the minds of the government and I may be forced to choose between irradiation or a grope. My flights planned for later this year will be out of an airport that does not have the NOS...SNA here I come. I will be sending letters along with receipts to the SAN airport authority, county commission and city council with an explanation as to why. I'm going to attempt to be a one man crusade to let the city know they are losing money because they allow this unconstitutional charade to take place in our city. I don't know if it will have an impact. But who knows, maybe I will be the one squeaky wheel that gets some attention. |
ETD machines can be programmed to detect just about anything, not just explosives. Here are some of the things that they can be programmed for that have an application useful to the TSA.
RDX (cyclotrimethylenetrinitramine) PETN (Pentaerythritol tetranitrate) TATP (triacetone triperoxide) HMTD (Hexamethylene triperoxide diamine) SEMTEX (Contains for RDX and PETN) NITRO (nitroglycerine) TNT (Trinitrotoluene) HMX (cyclotetramethylene-tetranitramine) The ETD systems are designed to detect trace elements that are contained in explosives using (most commonly) Ion mobility spectrometry, electron capture detection, electrochemistry, and olfaction . If one looks on the component listing of the various products they buy for personal use you may indeed find some of these base chemicals listed, which is why the ETD’s may occasionally alarm on your hand lotion or whatever. These are not “false positives” but actual detection of the chemicals they were designed to detect. ETD machines cannot perform a complete chemical breakdown of the samples provided, they are just not designed to do that. They can only tell us when they detect what they are programmed to detect. TSO’s are not chemists and anyone who expects us to be has some serious problems with reality. If an alarm happens they we need to find out why, it’s as simple as that. That means a search, since lie detectors are somewhat unreliable. TSA is currently testing several different types of ETD based systems such as FIDO (http://en.wikipedia.org/wiki/Fido_Explosives_Detector), the SABRE 2000, plus other technologies like the BLS (Bottle Liquid Scanner), SSD (Shoe Scanning Device), and many more.
Originally Posted by fishferbrains
(Post 16212675)
Let's turn this around for a moment:
Has there EVER been a documented case where the TSA has detected explosives in passenger luggage? You would think the TSA would make a big deal about this. Have they? |
Originally Posted by TSORon
(Post 16213787)
ETD machines can be programmed to detect just about anything, not just explosives. Here are some of the things that they can be programmed for that have an application useful to the TSA.
RDX (cyclotrimethylenetrinitramine) PETN (Pentaerythritol tetranitrate) TATP (triacetone triperoxide) HMTD (Hexamethylene triperoxide diamine) SEMTEX (Contains for RDX and PETN) NITRO (nitroglycerine) TNT (Trinitrotoluene) HMX (cyclotetramethylene-tetranitramine) The ETD systems are designed to detect trace elements that are contained in explosives using (most commonly) Ion mobility spectrometry, electron capture detection, electrochemistry, and olfaction . If one looks on the component listing of the various products they buy for personal use you may indeed find some of these base chemicals listed, which is why the ETD’s may occasionally alarm on your hand lotion or whatever. These are not “false positives” but actual detection of the chemicals they were designed to detect. ETD machines cannot perform a complete chemical breakdown of the samples provided, they are just not designed to do that. They can only tell us when they detect what they are programmed to detect. TSO’s are not chemists and anyone who expects us to be has some serious problems with reality. If an alarm happens they we need to find out why, it’s as simple as that. That means a search, since lie detectors are somewhat unreliable. TSA is currently testing several different types of ETD based systems such as FIDO (http://en.wikipedia.org/wiki/Fido_Explosives_Detector), the SABRE 2000, plus other technologies like the BLS (Bottle Liquid Scanner), SSD (Shoe Scanning Device), and many more. Yes, its not really all that uncommon. Explosives are used not just by terrorists and the military but by quite a few different commercial concerns and police agencies. Hence the reason we dont make a big deal out of it, its about like finding a 1955 penny in a bucket full of pennies. |
Originally Posted by FriendlySkies
(Post 16213822)
Did you cite all of your sources for that info you posted?
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Originally Posted by TSORon
(Post 16213787)
Yes, its not really all that uncommon. Explosives are used not just by terrorists and the military but by quite a few different commercial concerns and police agencies. Hence the reason we dont make a big deal out of it, its about like finding a 1955 penny in a bucket full of pennies. |
Originally Posted by TSORon
(Post 16213787)
ETD machines can be programmed to detect just about anything, not just explosives. Here are some of the things that they can be programmed for that have an application useful to the TSA.
RDX (cyclotrimethylenetrinitramine) PETN (Pentaerythritol tetranitrate) TATP (triacetone triperoxide) HMTD (Hexamethylene triperoxide diamine) SEMTEX (Contains for RDX and PETN) NITRO (nitroglycerine) TNT (Trinitrotoluene) HMX (cyclotetramethylene-tetranitramine) The ETD systems are designed to detect trace elements that are contained in explosives using (most commonly) Ion mobility spectrometry, electron capture detection, electrochemistry, and olfaction . If one looks on the component listing of the various products they buy for personal use you may indeed find some of these base chemicals listed, which is why the ETD’s may occasionally alarm on your hand lotion or whatever. These are not “false positives” but actual detection of the chemicals they were designed to detect. ETD machines cannot perform a complete chemical breakdown of the samples provided, they are just not designed to do that. They can only tell us when they detect what they are programmed to detect. TSO’s are not chemists and anyone who expects us to be has some serious problems with reality. If an alarm happens they we need to find out why, it’s as simple as that. That means a search, since lie detectors are somewhat unreliable. TSA is currently testing several different types of ETD based systems such as FIDO (http://en.wikipedia.org/wiki/Fido_Explosives_Detector), the SABRE 2000, plus other technologies like the BLS (Bottle Liquid Scanner), SSD (Shoe Scanning Device), and many more. Yes, its not really all that uncommon. Explosives are used not just by terrorists and the military but by quite a few different commercial concerns and police agencies. Hence the reason we dont make a big deal out of it, its about like finding a 1955 penny in a bucket full of pennies. I have a solution. It's called DESIGN A MACHINE THAT CAN DETECT THE ENTIRE COMPOUND. And yes it can be done. But companies are being asked to instead design machines that look up our butts and try to find a person who is sweating cause they MIGHT be a te****ist. And trust me...nobody will mistake TSA smurfs for chemists. Garbage men maybe. Pedophiles probably. But no, not chemists. |
Originally Posted by phoebepontiac
(Post 16213869)
But some people report getting an extra intrusive back room custody frisk as a result of a positive swab. I'd call that a big deal. And what about the guy who got his shoes confiscated? And the person whose hair conditioner caused, what was it, two hours of freaking out over everything in her bag, with multiple TSA folks and LEO's involved? These are anecdotes, yes, but there are enough of them to call your "not a big deal" into question.
Originally Posted by TXagogo
(Post 16213928)
I have a solution. It's called DESIGN A MACHINE THAT CAN DETECT THE ENTIRE COMPOUND.
Originally Posted by TXagogo
(Post 16213928)
And yes it can be done. But companies are being asked to instead design machines that look up our butts and try to find a person who is sweating cause they MIGHT be a te****ist.
|
Originally Posted by TSORon
(Post 16213787)
ETD machines can be programmed to detect just about anything, not just explosives. Here are some of the things that they can be programmed for that have an application useful to the TSA.
|
Originally Posted by TSORon
(Post 16213787)
ETD machines can be programmed to detect just about anything, not just explosives. Here are some of the things that they can be programmed for that have an application useful to the TSA.
RDX (cyclotrimethylenetrinitramine) PETN (Pentaerythritol tetranitrate) TATP (triacetone triperoxide) HMTD (Hexamethylene triperoxide diamine) SEMTEX (Contains for RDX and PETN) NITRO (nitroglycerine) TNT (Trinitrotoluene) HMX (cyclotetramethylene-tetranitramine) The ETD systems are designed to detect trace elements that are contained in explosives using (most commonly) Ion mobility spectrometry, electron capture detection, electrochemistry, and olfaction . If one looks on the component listing of the various products they buy for personal use you may indeed find some of these base chemicals listed, which is why the ETD’s may occasionally alarm on your hand lotion or whatever. These are not “false positives” but actual detection of the chemicals they were designed to detect. ETD machines cannot perform a complete chemical breakdown of the samples provided, they are just not designed to do that. They can only tell us when they detect what they are programmed to detect. TSO’s are not chemists and anyone who expects us to be has some serious problems with reality. If an alarm happens they we need to find out why, it’s as simple as that. That means a search, since lie detectors are somewhat unreliable. TSA is currently testing several different types of ETD based systems such as FIDO (http://en.wikipedia.org/wiki/Fido_Explosives_Detector), the SABRE 2000, plus other technologies like the BLS (Bottle Liquid Scanner), SSD (Shoe Scanning Device), and many more. Yes, its not really all that uncommon. Explosives are used not just by terrorists and the military but by quite a few different commercial concerns and police agencies. Hence the reason we dont make a big deal out of it, its about like finding a 1955 penny in a bucket full of pennies. |
Hmmm... Fireworks use Black Powder.. which (unlike modern Smokeless propellant) IS actually an "Explosive"*... (not a terribly efficient/powerful one of course) but an explosive nonetheless...
* classified as "1.1D" on the NATO system IIRC... Wonder if that's why the "puffer" machines alarmed? They actually worked????:eek: |
Originally Posted by CalVol
(Post 16213547)
I will be sending letters along with receipts to the SAN airport authority, county commission and city council with an explanation as to why.
I'm going to attempt to be a one man crusade to let the city know they are losing money because they allow this unconstitutional charade to take place in our city. I don't know if it will have an impact. But who knows, maybe I will be the one squeaky wheel that gets some attention. I've already sent such letters to the mayor, airport manager, and convention bureau in STL. Since it's now been 2 months since the TSA Contact Center promised I would hear from a customer service manager at SAN regarding my 30 minute detention for declining the free cancer dose, I will be giving the leaders of San Diego some "nice" letters, as well. CalVol, keep it up! |
Originally Posted by trooper
(Post 16214821)
Wonder if that's why the "puffer" machines alarmed? They actually worked????:eek:
|
Originally Posted by TSORon
(Post 16213787)
Yes, its not really all that uncommon. Explosives are used not just by terrorists and the military but by quite a few different commercial concerns and police agencies. Hence the reason we dont make a big deal out of it, its about like finding a 1955 penny in a bucket full of pennies.
It's also a big deal that my tax dollars are being used to abuse to me and anyone else who happens to want or need to fly!!! Then throw in the cavalier attitude of the folks paid to abuse us and, well, I better stop now before being sent to the penalty box.:mad: |
Originally Posted by trooper
(Post 16214821)
Hmmm... Fireworks use Black Powder.. which (unlike modern Smokeless propellant) IS actually an "Explosive"*... (not a terribly efficient/powerful one of course) but an explosive nonetheless...
* classified as "1.1D" on the NATO system IIRC... |
Originally Posted by trooper
(Post 16209394)
Avoid the firing range?
I travel to the USA regularly for target shooting competitions... so lots of my clothes/gear would be well contaminated by residue from the smokeless propellants I use.. especially my range bag which has done double duty as my carry on... never had a problem. I have even travelled with a powder thrower.. had THAT in my carry on (it's an expensive item and not terribly rugged) and presumably because it was an unusual looking thing they took it out of the bag and wiped the swab around the interior of the powder reservoir.... NO result... So.. from that experience.. I wouldn't be real concerned about flying after being at the range! :D I'm convinced that the machine is just a random number generator. |
Originally Posted by TSORon
(Post 16214041)
If we were to make a big deal out of incidents such as you describe what purpose would it serve?
It can ‘eh? Can you provide us with a link to such technology please? I for one would be very interested in reviewing the technical specifications. As for proven "technology", they're called D-O-G-S. As they are a highly mobile and effective deterrent and screening force; why would we invest otherwise? |
Originally Posted by Combat Medic
(Post 16218069)
I have a good friend that used one backpack for a year carrying mines, grenades, and C4. A month later he used it as a carry on and the TSA's swabs didn't find anything.
I'm convinced that the machine is just a random number generator. Just another page out of the play? |
Originally Posted by fishferbrains
(Post 16218142)
As for proven "technology", they're called D-O-G-S. As they are a highly mobile and effective deterrent and screening force; why would we invest otherwise?
|
I had a swap alert in MIA a couple months ago. TSO walked over to the other machine. It gave an all clear and I was on my way.
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