[old_tv_nut]

The high voltage rectifier should not be a significant source of x-rays as far as I can figure - The voltage across it is low when it's conducting and high when it's not conducting.

The high voltage regulator, however, has high voltage on it while conducting. If all the elements are aligned well, the internal elements provide quite a bit of shielding; the scare started with tubes that were improperly constructed. If no one is going to be below the bottom of the regulator, and you keep some distance, it's probably OK. The caution I would add is that I don't know how to differentiate between a proper and improper tube by eye.