What is defined as radiation that emerges from the leaded tube housing in directions other than that of the useful beam?

Leakage radiation is defined as the type of radiation that escapes from the leaded tube housing in directions that do not contribute to the useful beam projected towards the target. This radiation is a concern in radiology because it can increase the exposure of individuals to ionizing radiation, which is undesirable.

Leaded tube housing is designed to confine the useful beam while blocking or reducing the intensity of any stray or leakage radiation. The presence of leakage radiation can indicate potential issues with the integrity of the tube housing or that the equipment is not functioning properly, thus raising safety and regulatory concerns.

Other terms mentioned, such as scatter radiation, refer to radiation that has interacted with matter and is re-emitted in different directions, and secondary radiation typically arises as a result of the interaction of the primary beam with materials in its path (like patient tissues or the surrounding environment). These concepts are important but distinct from leakage radiation, which specifically refers to unattenuated radiation coming from the equipment itself rather than being a product of interactions with external materials.