Which term best describes a physical barrier that contains the beam and prevents radiation from exiting the system?

• A. Warning System
• B. Master Switch Control
• C. Administrative Controls
• D. Protective Housing

Answer: (D)

The main idea here is a solid, physical enclosure that encloses the radiation source and beam path to stop radiation from escaping. This is provided by the protective housing, which acts as the primary barrier containing the beam. It’s designed with shielding material and may include interlocks to ensure the system can’t operate when access points are open, so leakage is physically prevented. Other options describe ways to manage risk (warnings, procedures, or turning the system off) but do not by themselves form a physical barrier. That containment role is exactly what a protective housing provides.