Today the Houston TSA did something I've never experienced or seen before, or even heard of. I was selected out of the line at security. Then they swabbed both sides of both of my hands and then put the swab in a machine. The machine reported back in red, explosive material. Thereupon I was padded down all the way and all my carry-on stuff was examined. They took all of my electronics into another room for further investigation. After a half hour of this crap I became an American again.

Does anyone know what this machine is? Why would they pull a gray haired retired gent out of line to go through this? Is this done at other airports?

The machine is an Explosives Trace Detector. These are very common -- I can't think of the last airport I've seen that didn't have them by the security screening. Some fraction of people get swabbed. E.g., I've been selected "randomly" more times than I can remember, I've gotten swabbed every time I've opted out of the backscatter x-ray machines, and recently I got swabbed when I got the dreaded SSSS (presumably random), too.

I haven't read anything about the false positive rate (e.g., how often the machine indicates explosives when there aren't any, as in your case). If it's low enough, then how you were treated doesn't strike me as unreasonable (and this coming from me, who is no fan of airport security theatre). On the other hand, if the false positive rate is high (say, more than a tiny fraction of a percent), then putting you through a 30 minute delay is unacceptable.

The facts that you are gray-haired, retired, and a gentleman are irrelevant, and should not be factors in reducing security. You don't have to be young, employed, and impolite to blow up an airplane. (Well, actually, since a true gentleman wouldn't be a terrorist, that should be grounds for bypassing security. The problem, though, is how to distinguish a true gentleman from someone who is just pretending. )

An interesting question is what caused the false positive. Do you take nitroglycerin for a heart condition? Have you been handling anything explosive or chemically similar (fertilizer, perhaps?). If we can figure out what caused the false alarm, we might save ourselves a bunch of time the next time we fly.

I experienced this in Copenhagen, only there they pulled every other passenger. My husband walked through, I was swabbed, and so was my purse. There were sweet and polite, offered me a chair to sit.

They didn't find anything wrong, so no additional searches. My husband was relieved to know he is not married to a criminal

I am gray-haired too, but tell me please, what would stop me from trying to smuggle something? My age? Yeah, right! Or what would stop somebody from dropping something in my bag when I am not looking? TSA just doing their job.

How do people with colostomy bags make it through security?
Good luck if you played golf on a recently fertilized golf course.
When he was in the Marine Corps, my son had a cast on his hand when he qualified with his rifle. They took several swabs that indicated his hand and the cast was explosive.
I suppose the TSA has a quota for the number of people they have to harass every day. I am all for the women who go through security in bikinis.

EDS trace machine is what they put you through

They have done it to me coming back from Colombia

Last year...they have a daily quota to meet chemical combos of all kinds

Can trigger a false positive

Solo males Tend to win this lottery a lot in my experience

Prefer Colombia detection methods they have cute little yellow lab dogs

In nifty blue uniforms to match their handlers think their noses are better too

I have gone through that in a couple European countries.... Didn't even stop to think it was because I'm old...... LOL

Those swab machines are pretty normal at most TSA posts. I think some hand lotions will even set them off...so they are less than reliable...