Yesterday I used the TSA Pre-Check lane at a major U.S. airport, and as I went through the metal detector, the "random beep" went off. Fine. I'm pointed to the millimeter wave scanner, and I politely indicate I'm opting out. The agent hollers "Female Opt Out!" about a dozen times while I patiently wait. He periodically apologizes for the delay.

Meanwhile, my bags are sitting on the conveyor belt on the other side of security, having gone through the x-ray machine. I see two problems.

1. Any idiot could grab my bags. Goodbye wallet, goodbye ID. Not TSA's problem, so I understand why they don't really care about this.

2. Bigger problem. If I really were trying to conceal anything, anyone who was traveling with me but wasn't selected for random screening could just grab my bags and head to the gate. Once I clear my secondary screening (which would now be easier and quicker, since there are no bags to inspect!), we would just reconnect at the gate and I'd have all my stuff back, minus the obligation to have it go through the secondary screening by TSA.

I haven't actually tried this, but it strikes me as a big gaping hole in the security process. What am I missing?

If they didn't call a bag check on your bags they are considered cleared.

The bags have been inspected so there is no more risk in someone else grabbing them and boarding than if you grab them and board.

I don't think there's a real concern here.

I respectfully disagree.

Every time I've been randomly selected, I have been asked to identify my bags and they are brought by the agent to the secondary screening area.

If I fail the swab test (which I often do because I'm not going to stop wearing lotions that contain glycerine every time I fly), then my bags are manually inspected. And during that manual inspection, everything is swabbed and checked.

So I still think there's a problem here. If my bags were considered cleared, then TSA wouldn't be manually inspecting them when I fail a swab test. But given current procedures, one can easily avoid having their bags manually inspected upon random screening with the simple cooperation of a travel buddy.

Not to mention how poor the TSA's failure rate is at catching prohibited items. So no, the fact that they came through the x-ray doesn't mean they're safe at all...

TSA and gapping hole are synonymous.

1) When I have to opt out or get a random I watch my bags like a hawk. If TSO complains about me moving out the area they ask me to wait in I remind them I keeping my possessions secure. Once when my bags were going out of my sight I asked a one stripper to get them for me (they did). The TSO in charge was miffed.

2) If you really wanted to conceal something you would just keister it. The TSA ain't gonna find anything where the sun don't shine. That is the gapping hole.

Why opt out of the MMW scanners? They're not the old cancer boxes and they don't display images, either.

Why? Because they work so poorly that they regularly generate false positives. You get a patdown if you have a positive.

So, if I'm getting a patdown anyway, why go through the machine first?

Without getting into details about my own personal medical history, I'll tell you this. The millimeter wave scanners emit nonionizing radiation that is not believed to produce DNA damage that would lead to cancer. However, they use a form of electromagnetic radiation in a spectral region that can produce thermal effects, that is, heat. It's believed that the exposure we're talking about here doesn't actually heat tissue, but no one has determined the long-term effects of exposure (if any). Since it's easy for me to opt out, I do.

I take lots of other known and unknown risks in my life. This one I skip. Happy to live in a world where I get to make that choice for myself, and you get to make that choice for yourself.

Even when it false positives you get less of a pat-down than if you opt out.

There's no reason to think this poses any hazard. It's certainly far less than you get from a cell phone.

Far less than you get from a cell phone?

Evidence to support that claim?

Seriously, dude, not going to debate this with you. You make your decisions about which scanners to go through, and I'll make mine.

Consider the range.

The same thing applies even without an opt-out. In the airport I usually handle most or even all of the luggage. She tends to be transporting things that confuse the x-ray operator and get inspections--I always grab the bags that didn't alarm so they only end up searching whatever bag alarmed, not the rest of our stuff.

My experience says that's not always true.