On the topic of equivalent sensitivity of enlaring paper, Google AI says: "However, if you're using enlarging paper as a "paper negative" in a camera, you'll need to think in terms of a film ISO equivalent.
Photography Stack Exchange notes that a good starting point for modern enlarging papers used in this way is around ISO 6. Other sources suggest a range of 2-10, or even 3-6 for multigrade RC papers. "
Just as the title says. I'm diving into pinhole photography and I want to calculate exposure time, but it depends on the paper's ISO. The most available photographic paper for me is Ultrafine B/W
photo.stackexchange.com
ISO 5-10 would be about -8 to -9 EV compared to ISO1600,, or about 1/128 as sensitive as ISO 1600, and (assuing one diagnostic CT exposure is 100x the exposure of one diagnostic x-ray), one might 'ballpark' that enlarging paper undergoing CT is at-risk to same level of damage as ISO 1600 film thru security x-ray, if my logic has not failed me.
What we have no assessment about is the degree of damage from Secusity CT being same or less than the degree of damage from Cargo CT, which we know from past testing by Kodak and Ilford is very likely to damage even ordinary ISO photographic film.