Meanwhile, untrained TSA employees are rolling out hundreds of new radiation scanners at airports. The technology is different but TSA malfunctions are simply a matter of time...
I love to hate on TSA as much as the next guy, but the "technology difference" to this medical device is the difference between a nerf gun and a sniper rifle.
The point is that medical professionals can't properly handle a sniper rifle, do you trust TSA employees with any level of radiation deployed on a massively larger scale?
This kind of fearmongering is even worse than what the TSA does. Sure, the X-ray machines could mysteriously fail in such a way as to irradiate you. But it's very, very, very unlikely.
(What's the difference between backscatter x-ray and linear accelerators for surgery? The backscatter machine is designed to emit low levels of radiation. The linear accelerator is designed to send a beam of damaging radiation into the subject. The problem that the article describes was that the radiation beam designed to damage stuff was pointed at stuff that it shouldn't have been pointed at.)
Also, doctors are supposed to be skilled operators, and their machines are designed for that. TSA agents are not supposed to be skilled operators, so the machines they use don't have any knobs that they can tweak incorrectly.
While I agree with the general thrust of your comment, the machines used by the TSA are not "focused" in the same way. It would take much greater effort to create hazardous conditions like these patients experienced.
The TSA systems (at least the backscatter X-ray) do use a focussed moving beam to build up an image. They rely on the continual movement of the beam to limit the dose.
There are a number of safety systems to prevent the machine leaving the beam on should the mechanism stick.
And of course they are operated by the finest trained experts with a comprehensive background in nuclear physics and the ability to react in the fraction of a second before a notifiable dose was delivered