For a dropped fuel assembly in the spent fuel pool: 2R5 or 2R9 area radiation monitors will detect the release and alarm. When either reaches alarm setpoint, FHB ventilation automatically starts both exhaust fans and shifts filter alignment to HEPA Plus Charcoal filters. CAV does NOT shift to Accident Pressurized mode (that would require containment release via 2R2 or 2R10A/B). The containment radiation area monitors (2R2, 2R10A/B) would only alarm if the fuel incident occurred inside containment.

Fuel assembly in mast tube in transit approaching the core during reload (containment): "Place the fuel assembly in the mast tube into the core in its designated location or the emergency location P-10 whichever is closer." Trap: X-3 is the emergency safe location in the FHB, NOT in containment — P-10 is the containment emergency location. The upender (horizontal position) is only used if P-10 is not available or the assembly is indexed above the upender.

Per AB.FUEL-0001, the canal gate valve will be closed for any fuel handling incident (Step 3.16) — regardless of whether the incident is inside containment or in the FHB. The canal gate valve can ONLY be FULLY closed with the fuel transfer cart inside containment due to a mechanical interlock. The interlock requires the cart to be inside containment (not in the FHB) for the valve to fully close.