What is the primary purpose of sealed source jackets in radiopharmacy?

• A. They provide containment to prevent spills and leaks.
• B. They calibrate the activity for dosing.
• C. They shield fully in all directions (like shielding blocks do).
• D. They provide cooling for the source.

Answer: (A)

Containment of the radioactive material is the main function of a sealed source jacket. The jacket surrounds the sealed capsule to form a leak‑tight barrier, keeping any contents from escaping into the work area or onto staff and surfaces. This is crucial for safety during all handling, storage, and transport, because even small leaks can contaminate equipment, surfaces, and people. Shielding and cooling are important safety considerations too, but they come from separate design features and systems: shielding is provided by appropriate shielding materials around the source or by its encapsulation, and cooling is only needed in particular situations, not the jacket’s primary role. Calibrating the activity is done with dedicated equipment and standards, not by the jacket itself.