Leakage radiation is all radiation escaping from within the source assembly except for the useful beam. It is primarily controlled through the design of the tube housing and proper collimator filtering.

Stray radiation is the sum of leakage radiation and scattered radiation.

The x-ray tube housing is a cover for x-ray tubes to prevent leakage radiation to exceed specified limits. X-ray tube housings can be open or sealed.
The maximum permitted radiation measured at a distance of 1 m from the source is 0.876 mGy air kerma (100 mR exposure) in 1 h when the x-ray tube is operated at its maximum continuous rated current for the maximum rated tube potential.