The hypothetical situation is actually a very real problem for those who travel and shoot film of any format size. The scanners as I pointed out are in fact detrimental to photographic material.
The main point I have tried to make is that the TSA folks in large part are not educated on the finer points of film sensitivity nor on photography in general.
The TSA (and speaking as one who have friends who are TSA agents BTW) are more concerned over playing their Game Boys, their kids, buying food and doing their general day to day ritual like so many others. Many are there to have a paycheck whilst they attend school and unless they are shutterbugs themselves, look at photography through the lens of their iPhones.
Most do not have the desire nor the incling to learn about the effects of CT scanners on the lives of others, they are there to do a job.
The TSA does have a specific part in their training dealing with film and photographic material and do train to a small degree the effects the scanners have on film.
Film
The main point on that page is at the bottom:
"The final decision rests with the TSA officer on whether an item is allowed through the checkpoint."
Many I know inside the TSA have expressed angst over the over-bearing attitude that they are required by their jobs to project, and as I stated, most are not versed in the finer points of silver halide sensitivity to electromagnetic radiation in the 0.03 to 3 nanometer range.
The effects on light meters may or may not be an issue but IMO this is a question best figured by contacting the manufacturers of said light meters and as I always point out....
If you don't like the situation,
Move to change it! Contact your members of congress and all powers that be to address the issue.