Kodak's previous published wisdom a few years ago:
  1. With film of ISO 400 and less, the carry-on baggage scanner is safe for multiple passes of the film thru scanner
  2. With film of ISO 1600 and higher, try to get your film hand inspected (which NEVER WORKS in London Heathrow airport!!!!)
  3. NEVER EVER put your film thru checked luggage, which is put thru a CT Scan which will ruin unprocessed film