Which isotopes are considered activated corrosion products?

• A. Co-60
• B. Co-58
• C. Mn-54
• D. All of the above

Answer: (A)

Activated corrosion products are radioactive isotopes formed when corrosion-related materials in the reactor are exposed to neutron flux and become activated. Cobalt is a common impurity in stainless steel components, so when cobalt atoms in corrosion products capture neutrons they become cobalt-60. Cobalt-60 emits strong gamma rays and has a long enough half-life to persist in the system, making it the most significant and widely recognized activated corrosion product in many reactor dose-rate assessments. While other isotopes like cobalt-58 or manganese-54 can also be produced, cobalt-60 is the best representative of activated corrosion products due to its prominent gamma emissions and lasting activity.