I've had about 20 pat downs in many different airports. I've never had to wait more than three minutes for someone and everyone has always been professional and courteous. As much as I hate the TSA and complain about them, the airport staff has been nice and helpful. In two or three cases they went out of their way to help me, beyond what I expected.

Edit: I should also add that I'm a middle class white male who looks "respectable". I'm not going to experience the discrimination some minorities may endure so take that for what it's worth.

But each time they ask me if there are any sensitive areas, each time I tell them, "Yes, my nuts", and each time they been respectful of my junk.

They really could do better about keeping people with their stuff that's been passed through the X-ray machine, but overall they seem to appreciate that you want to keep an eye on it.

edit: Also, the most shocking part of the whole ordeal is usually the looks from the OTHER people in line, like they think you're going to be killed or assaulted, or "why don't you just cooperate, it's easier". That's the part that really makes me sad.

[1]http://fivethirtyeight.blogs.nytimes.com/2012/10/18/gallup-v...

[2] http://www.huffingtonpost.com/2012/06/17/gallup-poll-race-ba...

[3] http://andrewsullivan.thedailybeast.com/2012/10/rasmussen-an...

It's like asking: is abstinence effective for preventing stds? And then inferring that people prefer abstinence to condoms.

Efficacy isn't as useful as how an issue plays on the emotions of voters.

These scanners exposé you to less than 1/200th the radiation dose of a standard plane flight, and between 1/200th and 1/400th of a standard chest X-ray.

Yes, ionising radiation can cause cancer. But your chance of getting cancer anyway is 1 in 2.4.

I have no love of excessive security measures, and I personally don't think that we should ever unnecessarily cause people to be exposed to radiation, especially when other methods can do the same job without radiation, and even moreso when the efficacy of the scanners is unproven.

But I have a particular dislike of the psychogenic claims that arise around technologies that posit to do this or that, when the action of the machine or technology in question is noninvasive and especially when the action is not substantively different from normal daily exposures that every human receives anyway

Refs:

standard CXR 2.4x background radiation

Backscatter Imaging 6-7% of a days background radiation (0.25 microsiverts per 'scan =1.5hrs @ background radiation or 2 minutes of an airplane at altitude)

Abdo CT: 2.7 years BG radiation

- http://www.medicalnewstoday.com/articles/219970.php

- http://en.wikipedia.org/wiki/Backscatter_X-ray

Their contention is that the argument that the backscatter x-rays are 1/200th of the dose you get from cosmic radiation on a flight is invalid, as the backscatter x-ray is specifically designed to direct the radiation to a very thin layer of surface tissue, whereas cosmic radiation is distributed throughout the entire body.

Yes, these professors were refuted by other UCSF radiology professors [2], but the science will not be settled until an independent study is conducted of the machines given the context of their potential for misuse and mis-calibration by individuals who are not radiology technicians.

So if you don't want your comment to come off as offensive, perhaps it would be wise to not start off with "Are you making this up, ill-informed or do you not understand physics and radiation?"

[1] http://www.whitehouse.gov/sites/default/files/microsites/ost...

[2] http://blogs.sfweekly.com/thesnitch/2010/11/tsa_scanner_cont...

You pretty much back up my point. People who don't know the science should not comment in alarmist tones about it.

Fearmongering generally does more harm than good. In this case it seems like everyone hates the TSA, hates the full body scanners, objects to being dosed with radiation, and so psychogenic illnesses are claimed to be caused by the machine.

So the claims are false, the machines work like they're supposed to, it's just no one wants them there so hurdles are placed in the way of their implementation. Hurdles that are false.

I don't disagree that we should look further into the use, especially as I say above because there are other methods that do not use ionising radiation that seem to be just as effective

So yes, I would take the same attitude to the 3 UCSF Med school professors, just as I have to the world-famous neurosurgeon who told me as we microwaved our food in between surgeries that I had to 'wait for 3 seconds after it finishes or else the rays escape and can increase your risk for cancer' or the former head of the AMA who said during a lecture that 'there is a study that shows that homeopathy is active against cancer' with no supporting evidence. Position and title generally only qualify a person to make comments in a specific domain, as those 3 professors discovered when they got smacked down by the radiologists.

If people want to believe weird and wacky things, that's fine. If those things contravene the known laws of physics, then either there must be some spectacular evidence, at which point I will believe anything, or it simply isn't true.

you make the claim They are likely unsafe, and some small subset of people scanned may end up quite sick.

But there is still no evidence from what you are saying. I felt, in another variation of Poe's law, that you were in fact making a claim re backscatter for people claiming sickness after moving through one. In the same manner that people claim that they can detect wifi signals and it makes them sick, or fluoride in the water is making them sick, or just why are there rainbows in our water these days?

Quoting figures I feel is even more relevant - if you are giving someone 1/200th of a CXR, you can't claim that the CXR is only penetrating the internal organs - some fraction, perhaps 1/200th (maybe less) is going to be absorbed by the skin too, because, as you would well know, that is how X-rays work.

The fact we have greater penetration at the higher energies used for a CXR or other diagnostic imaging does not rule out using the comparison to Backscatter X-rays. In fact, it can be used to validate it.

Please note again that I am not suggesting that these machines should be rolled out everywhere and that we should have to use them, because I think it's a stupid security measure.

Sounds like you're describing the dystopian future we read about and see in movies.