DANB Radiation Health and Safety (RHS) Practice Exam

Ionizing radiation is capable of producing ions when it:

1. Is absorbed by body tissues

2. Is emitted from isotopes

3. Passes through the atmosphere

4. None of the above

The correct answer is: Is absorbed by body tissues

Ionizing radiation is characterized by its ability to remove tightly bound electrons from atoms, thus generating ions. This process occurs when ionizing radiation interacts with matter, and the most common and illustrative setting for this interaction is when it is absorbed by body tissues. When ionizing radiation, such as X-rays or gamma rays, is absorbed by the tissue, it transfers energy to the electrons in the atoms of the tissue, giving them enough energy to escape from their atomic orbitals. This creates ions: positively charged ions (which have lost electrons) and free electrons (which can be negatively charged). This interaction is the fundamental mechanism through which ionizing radiation can cause biological effects, including damage to cells and DNA. While radiation can be emitted from isotopes or pass through various mediums like the atmosphere, these activities do not necessarily result in the production of ions unless there is an absorption event. Therefore, the correct answer emphasizes the importance of the interaction between ionizing radiation and body tissues in the context of producing ions.