(ThermoLuminescent Dosimeter. Radiation badge thing that indicates with exposure.)

Same with the commercial nuclear industry. They don't like you taking them off site most of the time.

Same thing with all imaging technicians in a hospital. Ex: X-ray, MRI, CT.

Wow, there is a similar comment above[0] suggesting radiation badges for flight crew. I was going to ask if typical badges are sensitive enough to register the expected dose from flight.

If I understand correctly, you're saying a single commercial flight is enough to trip the dosimeter?

[0] https://news.ycombinator.com/item?id=37178559

NYC-Tokyo over the polar route for a flight crew over an entire year gives you as much as a single full body CT.

A single full body CT of radiation every year for that flight crew.

Not necessarily, but if it gets xrayed going through security then when they heat it up so that it luminesces, it'll be so bright that it messes up their carefully calibrated detector. This is expensive to fix and the dosimetry people get really mad at you.

Source: wore one of these daily for years and would get regular reminders not to bring them on flights or anywhere else they would have to go through an xray machine (eg some federal buildings)