Activated corrosion products are formed as a result of neutron activation of which materials?

• A. Fission Gases
• B. Neutron Activation of Corrosion Products
• C. External Contamination
• D. Dissolution of Fuel

Answer: (B)

Activated corrosion products arise when corrosion products that have formed on reactor materials in the coolant are bombarded by neutrons. These corrosion products—oxide and particulate forms of metals like iron, nickel, chromium, cobalt, and other impurities—absorb neutrons and become radioactive isotopes such as cobalt-60, iron-59, or nickel-63. This is why the source material is the corrosion products themselves: they are already present in the coolant as a result of corrosion, and neutron exposure converts them into activated species delivering the radiation fields seen during maintenance. The other options don’t fit because fission gases come from fuel fission, external contamination is surface contamination not produced by activation in the coolant, and dissolution of fuel relates to fuel behavior, not activation of corrosion products.