It was stated previously that it is false that X-Ray machines will harm negatives below 1600. As much is not the case. X-Ray machines CAN impose "waves" on your negatives (below 1600), which produces a soft-glow or diffused look. While this won't always happen, it's honestly not worth the chance.(posted 8576 days ago)This past November, I was on a trip to Florida. On the way home, the airport security attendant refused to hand-inspect my camera bag and only after a verbal argument, would he hand-inspect my film.
The little man ranted on and on about how his X-Ray machine was safe up to 1600iso. He waved manuals and documentation, but sadly, the Plus-X pan [iso 125] film that was still in my camera came back quite fuzzy.
Folks, if you can get by the x-ray machine, then do. It's not worth ruining your film to make *their* job easier.