Accidents are defined as which of the following?

• A. Accidents are hypothesized events that affect one or more of the radioactive material barriers and that are not expected during plant operations.
• B. Incidents are routine faults that do not involve barriers.
• C. Accidents are routine events during maintenance.
• D. Accidents are random external events.

Answer: (A)

Accidents are hypothetical events that could compromise one or more barriers protecting radioactive material and are not expected to occur during normal plant operations. This framing matters because safety analyses model these unlikely, but potentially severe, events to understand potential consequences and ensure robust protection.

If an event is a routine fault that does not involve barriers, or a routine maintenance occurrence, or simply a random external event, it doesn’t meet the formal definition of an accident because such events are expected or do not necessarily challenge the barriers designed to keep radioactive materials contained.