Associate Safety Professional Practice Exam

When developing a list of single point failures in a fault tree analysis, what should you look for?

1. "And" gates

2. "Or" gates

3. Critical path nodes

4. Input variables

The correct answer is: "Or" gates

In a fault tree analysis, identifying single point failures is essential for understanding how specific component failures can lead to system failure. "Or" gates are particularly significant in this context because they indicate scenarios where failure can occur if any one of the input conditions (or events) leading into the gate fails. When you look at an "Or" gate, it represents a condition where the failure of one input will result in the failure of the system or higher-level event, making it critical to recognize which components or conditions are essential for maintaining system function. In contrast, "And" gates involve multiple inputs that need to fail simultaneously for the higher-level event to occur, which doesn't highlight a single point of failure. Critical path nodes are related to determining the longest stretch of dependent activities, focusing more on project timelines rather than individual components' contributions to overall system failure. Input variables are essential for defining the conditions in the analysis but do not directly indicate failure points. Therefore, focusing on "Or" gates effectively directs attention to potential single points of failure that can be mitigated or managed to improve overall safety and reliability.