Which term describes safeguards designed to prevent escalation once a reactivity hazard is detected?

• A. Primary containment
• B. Secondary containment
• C. Mitigative safeguards
• D. Emergency relief devices

Answer: (C)

Mitigative safeguards are the measures that step in after a reactivity hazard is detected to keep the situation from getting worse. They focus on reducing the severity of an event and preventing escalation, rather than just containing or preventing the initial release. Examples include automatic shutdown of the reactor if abnormal heat or reaction rates are sensed, isolating the reacting portion of the system, cooling or quenching to slow reactions, and routing materials to safe paths or scrubbers to limit consequences.

Primary containment and secondary containment are about keeping materials from escaping in the first place or containing them if a release occurs, not specifically actions taken after a hazard is detected. Emergency relief devices are designed to relieve energy or pressure to prevent a catastrophic failure, but they are typically considered protective mechanisms to prevent an overpressure event rather than ongoing mitigation once a hazard has been detected.