What is the function of containment isolation valves?

What is the function of containment isolation valves?

• A. To seal off containment penetrations and prevent leakage paths for radioactive material during normal operations or accidents.
• B. To regulate reactor feedwater flow.
• C. To adjust the reactor's neutron spectrum.
• D. To vent containment to the atmosphere.

Answer: (A)

Containment isolation valves seal containment penetrations to prevent leakage paths for radioactive material during normal operations or accidents. They create a robust barrier by closing off pipes that enter or leave the containment, so if a leak were to occur, the potential release is limited and contained. In normal operation they’re arranged to be ready to close if needed, and in an emergency or during maintenance they isolate the containment to protect the environment and personnel. They are not used to regulate feedwater flow, which is the job of feedwater valves; they do not adjust the neutron spectrum, which is controlled by reactor physics components like control rods and moderators; and venting containment to the atmosphere would defeat the purpose of containment isolation.

Containment isolation valves seal containment penetrations to prevent leakage paths for radioactive material during normal operations or accidents. They create a robust barrier by closing off pipes that enter or leave the containment, so if a leak were to occur, the potential release is limited and contained. In normal operation they’re arranged to be ready to close if needed, and in an emergency or during maintenance they isolate the containment to protect the environment and personnel. They are not used to regulate feedwater flow, which is the job of feedwater valves; they do not adjust the neutron spectrum, which is controlled by reactor physics components like control rods and moderators; and venting containment to the atmosphere would defeat the purpose of containment isolation.