Which group uses PRA when: Installing new safety-related equipment to the plant; Adding a backup cooling supply to a piece of safety-related equipment; Changing control room indications; Replacing an AOV with an MOV; Changing failure mode of equipment?

Which group uses PRA when: Installing new safety-related equipment to the plant; Adding a backup cooling supply to a piece of safety-related equipment; Changing control room indications; Replacing an AOV with an MOV; Changing failure mode of equipment?

• A. Maintenance
• B. Design Engineers
• C. Operators
• D. Systems Engineers

Answer: (B)

When evaluating changes to safety-related equipment, you use probabilistic risk assessment to quantify how the modification affects plant risk. Installing new safety equipment, adding backup cooling, updating control room indications, replacing an AOV with an MOV, or changing a component’s failure mode all alter how systems can fail and what accident sequences could occur. Design engineers apply PRA during the design process to model these changes, update fault trees and event trees, estimate any shifts in risk metrics like core damage or large early release frequencies, and ensure the overall risk remains within acceptable limits or is reduced. This risk-informed justification is central to their role, guiding design choices and ensuring that modifications meet safety targets. Other groups may provide data, implement the changes, or operate the plant, but the formal PRA work to support these design decisions is led by design engineers.

When evaluating changes to safety-related equipment, you use probabilistic risk assessment to quantify how the modification affects plant risk. Installing new safety equipment, adding backup cooling, updating control room indications, replacing an AOV with an MOV, or changing a component’s failure mode all alter how systems can fail and what accident sequences could occur. Design engineers apply PRA during the design process to model these changes, update fault trees and event trees, estimate any shifts in risk metrics like core damage or large early release frequencies, and ensure the overall risk remains within acceptable limits or is reduced. This risk-informed justification is central to their role, guiding design choices and ensuring that modifications meet safety targets. Other groups may provide data, implement the changes, or operate the plant, but the formal PRA work to support these design decisions is led by design engineers.