Some U.S. airports have new X-ray scanners at security check points called CT scanners. They're different from previous X-ray security scanners and you really need to avoid sending your film through them. CT Scanners can ruin unprocessed film!
According to the Transportation Security Administration's website, Computer Tomography (CT) “is similar to CT technology used in the medical field” and creates a 3-D image that can be viewed and rotated 360 degrees for a thorough analysis." Current X-ray screening technology for carry-on bags uses 2-D images.
According to the TSA, CT technology has been added to security checkpoints at the following airports as of November 2019. (If you don't see your airport on the list, we recommend you find out if they have CT scanners before you fly.)
Place undeveloped film and cameras containing undeveloped film in your carry-on bags and request a hand inspection during security screening.
Kodak has even updated their guidelines for the “Storage and Care of KODAK Photographic Materials” to reflect these new CT scanners, recommending photographers always hand-carry their film and always request a visual inspection at security checkpoints.
According to Kodak's guidelines, which you can download here, the end goal of TSA is to have CT scanners at every airport. (Shout-out to Kosmo Foto for originally breaking this important news here and here!)
Keep those rolls safe and base fog-free by following these best practices:
Avoid placing your film in a checked bag at all costs! The radiation of X-ray machines used to screen checked luggage is quite strong and will likely damage any film that passes through. What will this damage look like? It'll show up much like heat fog or base fog: cloudy, low contrast, extra grainy mush—yum. Occasionally, the damage also appears as a sin wave or line repeating through the roll. Fun times!
Instead, store your film in a zip-close bag and take it with you on board. Bonus: your precious rolls never leave your side! While checked luggage can disappear or take a detour, your carry-on and film stays with you.
When you reach security, request your film be hand-checked in lieu of sending it through a potentially damaging X-ray machine. Request denied? Not to worry, 800 ISO and lower can travel safely through multiple normal X-ray scanners (not CT scanners!) without noticeable damage. But keep in mind, radiation is cumulative, so play it safe and request your film to be hand-checked whenever possible.