iirc you need about 5+ passes to have visible xray fogging start to show up from normal carry on scanners from film. Each pass obviously does damage, otherwise no amount of passes would ever affect it.
As for checked baggage scan.. every roll with a sine wave on it I've gotten from others has gone through checked baggage.
Well, I got nothing visible at all on Portra 400 after 14 passes. Maybe you could measure it with a densitometer compared to a control roll but I cannot spot any difference in a side-by-side comparison.
Thanks for the input, everyone. I was fairly convinced there was nothing to worry about, then I read about the 'metal' aspect, and got to wondering. Now I again feel better about it all. I'll report the final outcome next week.
For most people this is well within the realm of "not a problem". I know for me it has never been, either.
For my travel through Canada and the US, this has never been an issue with films 50-800 ISO.
I did however get held up for ~15min once when I gave them my a12 film back and told them they couldn't open it!
The data is actually a bit old. It was from when they established the FAA reccomendations. I would assume that if done again the data would show even more film-safeness (if that is a word) with the newer equipment. Unfortunately I've lost my ties to the scanner manufacturers otherwise I'd ask them... but I think you might be correct about lower dosage levels. I know when I was working those issues the focus was on post-processing techniques to eliminate the need to "re-zap" items yet get better discrimination of contraband. At one time the manufacturers all had their specs online so I suppose with a little effort that could be verified rather easily.
I haven't had a problem with running roll film through security in the US and Western and Eastern Europe. I do carry my film separately from my camera bag because there have been times when they have been a little bit more inquisitive of the camera bag and have done multiple passes of it, or it has sat there for longer than I like. It hasn't been a problem, meaning it hasn't shown up on the negative, but I'd rather avoid it if possible.