2020 Q59 — Containment Ventilation Isolation

✓ D. Correct. The Phase B and Spray Actuation pushbuttons / keys also actuate Containment Ventilation Isolation. The signal goes to all the purge and pressure/vacuum relief valves. See drawing 221057.

✗ A. Incorrect. The first part is correct, the Phase B and Spray Actuation pushbuttons / keys also actuate Containment Ventilation Isolation. The second part is plausible because the candidate may believe that the signal only sends a closed signal to the purge isolation valves. Incorrect as the signal goes to all the purge and pressure/vacuum relief valves.

✗ B. Incorrect. Plausible because the student may believe that a Containment Phase "A" Isolation signal would also cause a Containment Ventilation Isolation. The second part is plausible because the candidate may believe that the signal only sends a closed signal to the purge isolation valves. Incorrect as the signal goes to all the purge and pressure/vacuum relief valves.

✗ C. Incorrect. Plausible because the student may believe that a Containment Phase "A" Isolation signal would also cause a Containment Ventilation Isolation. The second part is correct.

Ref: Safeguards Action Signals, Logic Diagram Sheet 8, drawing 221057 | LO: N/A | Source: Bank, Salem Vision Database | Cognitive: Fundamental