These are the three fundamentals of Radiation: Time, Distance, and Shielding. Time, the amount of time an object is exposed to X-Rays. Distance, the physical distance the object is to the X-Ray source. Shielding, anything that attenuates the beam of X-Rays, blocks them from the object, IE Lead.
For instance, I had a camera backpack loaded with my lenses and put it in the gray tray and sent it through the X-Ray machine for inspection. Because it was so full of lenses they literally went forward then back then forward then back then forward, then made comments to me, then forward then back. I would imagine that the backpack got plenty of X-Ray exposure. Maybe the equivalent of a dozen trips through the one pass method. Forward is one backward is two and on and on. So stuffing film in their with the lenses allows it to be given a dozen exposures of radiation.
I had my film in a shoulder bag which was in a separate gray tray with my coat or shoes, I forget which, and it got one pass. It seems there is no way or place that film is safe, it's a crap shoot whether the film will go for a radiation ride though the machine and back, or just stop and collect exposure, that's a strong possibility too. They pause and do a look see for a while. The only way to know what exposure is given to the piece of luggage is to have the right type of dosimeter in with the items. The dosimeter would have to be calibrated and there is really no way to do that with equipment that's untouchable so the bottom line is we as the public are screwed. It's getting more and more the case where any reasonable liberty is being taken away by a totalitarian entity. Make a scene or waves and you will be taken away to a room where you will be reduced of your rights permanently. Fumble through the system and you might be all right, but remember they are always watching you and what you do and how you react.
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