Which barrier is specifically designed to attenuate leakage and scatter radiation in a radiology facility?

• A. Secondary protective barrier
• B. Primary protective barrier
• C. Tertiary protective barrier
• D. Accessory barrier

Answer: (A)

The secondary protective barrier is the one designed to attenuate leakage and scatter radiation. Leakage comes from the x‑ray tube housing and is regulated to stay within safe limits, while scatter radiation arises when the x‑ray beam interacts with the patient and surrounding objects. The secondary barrier sits in the path those stray photons can take to reach nearby areas (like the control booth and adjacent rooms) and is built with enough lead to reduce those exposures to acceptable levels based on workload and occupancy. The primary barrier protects against the direct, primary beam, so it’s much thicker and not intended to handle leakage and scatter. A tertiary barrier is added only in specific, additional shielding situations, and an accessory barrier isn’t a standard term for this purpose.