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:

1. Explosives (duh)
2. Explosive powder residue (avoid the firing range)
3. Fertilizer (avoid gardening)
4. Certain hand lotions
5. Nitroglycerin heart medication
6. The leftover residue from the last person who used the same swab
7. Contaminant on the TSO's gloves
8. Potentially, the machine itself could be contaminated and/or not recently calibrated
9. Surprisingly often, for no reason in particular

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

Since no TSA employee has ever found real explosives, it's a sign of serious mental illness to continue to imagine that a "positive" from this goofy system implies the presence of a hazardous substance.

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.

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?

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.

Yes, legally. No, practically (see below).

Congress is composed entirely of cowards and B.S. artists. They care about only one thing: getting re-elected. So, if a plane gets hijacked, and Congressman X voted against TSA, Congressman X will be accused of being "soft on terrorism" and might lose an election.

Yes.

Yes, they ceded their power to TSA some time ago, so they wouldn't be bothered with actually having to vote for, say, groping of six year olds. Any excesses could be blamed on the agency, rather than Congress, so that one was a win-win for this crowd.

Nothing is happening. Nothing ever will. The terrorists have won.

And yet standing downwind of a fireworks show was enough to trigger the "puffer" machines in ATL before they were mothballed.

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.

+1

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!

Not for the person who get's falsely positive-d.