Which option is NOT one of the three fission product barriers?

• A. Fuel Cladding
• B. System Piping
• C. Containment Structure
• D. Control Rods

Answer: (D)

The concept being tested is how fission products are kept from the environment. The three barriers that keep fission products inside the plant are: the fuel cladding, which is the outer protective layer around the fuel; the reactor coolant system boundaries, such as the system piping that contains the coolant; and the containment structure, which is the robust outer shell designed to contain any released material. Control rods, while essential for stopping or limiting the nuclear reaction, are not a barrier to fission product release. They control reactivity and shut down the core, but they do not physically contain fission products if cladding or containment are breached.