I think that your concerns about invasion of privacy are unfounded, but I can’t speak to the health hazard issue. I did the operational testing for L3Com’s millimeter wave radar system. The system met the DoD standards for RF emissions, coming in far lower than many fielded RF emitters. I’ve been around that stuff so long, that my chromosones are probably fried anyway. I’ve been scanned by one of these things and would do it again if given the option.
As for the privacy issue, if you want a little sexual thrill, then a trip to the beach or the local supermarket are in order, the display on this thing is not that revealing. It will, however clearly show when someone is trying to conceal an object, it would have certainly detected this device provided the operator was paying attention.
“The system met the DoD standards for RF emissions”
How much do we know about 94 GHz radiation? That’s the same freq as the long-range “people cooker” pain ray that’s also supposed to be safe, as long as you run when you are hit with it.
They say the back scatter xray is safe, given that you get more radiation at altitude. The safety then is given as a relative hazard, not an absolute.