Apologies if this is common knowledge, but I learned it only today from a newspaper article (F.a.S.): The agents at the airport screening checkpoints obviously are not allowed to ask you to remove your belt as this is a piece of personal privacy (can‘t explain any better in english).

I was actually wondering a few times already why this is handled so differently around the world.

In any case, if you take it off it reduces the riks for a beep ...