Originally Posted by Newt_on_Swings
Newt are you talking about film in CHECKED luggage?? Because the banding lines only occur in checked bags. Kodak doesn't give a warning about carry on luggage unless it's being x-rayed 5 times. And with all the travel I do with film, I haven't had any issues with carrying on film, and I'll carry as much as 200 rolls at a time.
In the US by Federal regulation ( FAR section 108. 17 E, FAR 108.205 E) if you insist on a had search they HAVE to give you one. They may be reluctant, but they HAVE to do it anyway. I would be careful though if you're carrying sheet film, because I have heard from several people that when they handed over boxes of sheet film, they were opened. So if you travel with sheet film expect to get it x-rayed.
Also consider not just the exposure to x-ray scanners as a factor but flight duration. The longer the flight at high altitude the greater the exposure to cosmic and solar radiation. And not just your film, you too!!