2019 Q28 — Containment Airlock Interlock

✓ A. Correct. For Part 1 and in accordance with LCO 3.6.1.3 (Containment Air Locks), the Containment Airlock interlock mechanisms for BOTH Containment Airlocks are required to be OPERABLE when Unit 2 is in MODES 1-4 ONLY. For Part 2 and in accordance with LCO 3.6.1.3 (Containment Air Locks) REQUIRED ACTION B.1, if a containment air lock with only the containment air lock interlock mechanism is inoperable, then verify an OPERABLE door is closed only in the affected air lock within 1 hour.

✗ B. Incorrect but plausible. Part 1 is correct. For Part 2, LCO 3.6.1.3 REQUIRED ACTION B.2 has a requirement to lock an OPERABLE door closed in the affected air lock within 24 hours.

✗ C. Incorrect but plausible. For Part 1, the candidate could incorrectly conclude that the Containment Airlock interlock mechanisms for BOTH Containment Airlocks are required to be OPERABLE when Unit 2 is in ALL MODES. Part 2 is correct.

✗ D. Incorrect but plausible. For Part 1, the candidate could incorrectly conclude that the Containment Airlock interlock mechanisms for BOTH Containment Airlocks are required to be OPERABLE when Unit 2 is in ALL MODES. For Part 2, LCO 3.6.1.3 REQUIRED ACTION B.2 has a requirement to lock an OPERABLE door closed in the affected air lock within 24 hours.

Ref: LCO 3.6.1.3, NOS05CONTMT-15 (CONTAINMENT AND CONTAINMENT SUPPORT SYSTEMS) | LO: Describe the purpose and design basis for Containment Airlocks | Source: New | Cognitive: Lower