Event Tree Analysis (ETA)

Correct Answer: To model potential sequences of events following an initiating event and calculate their probabilities

Event Tree Analysis (ETA) is a logical modeling technique that visualizes and analyzes the possible outcomes of an initiating event and their probabilities. It uses a tree-like diagram to show how different events can unfold from a single starting point. ETA is specifically designed to track forward-moving chains of events and calculate the probability of various outcomes. It helps project managers understand potential consequences and their likelihood, enabling better risk response planning. The other answers are incorrect because: - Breaking down project activities and sequential relationships is more aligned with Work Breakdown Structure (WBS), not ETA - Mapping cause-and-effect scenarios through past project evaluation describes more of a lessons learned or root cause analysis approach - Calculating the mathematical product of all risk probabilities is not a valid risk assessment method, as risks often have complex interrelationships that cannot be reduced to simple multiplication

Correct Answer: Top to bottom, starting with the initiating event and following each possible outcome path

Event Tree Analysis (ETA) is most effectively conducted from top to bottom, starting with the initiating event and following each possible outcome path. This approach is logical and systematic because: 1. It begins with the initiating event that could trigger a series of consequences 2. Each branch point represents a possible outcome or system response 3. The analysis follows the natural progression of events as they would occur in time 4. It allows for clear visualization of success and failure paths 5. It helps identify all possible outcome scenarios systematically Other approaches are incorrect because: - Starting from the bottom up makes it difficult to establish proper cause-and-effect relationships - A middle-outward approach can lead to confusion and missed connections between events - Parallel path evaluation can create complexity and potential oversight of important sequential relationships The top-down approach ensures comprehensive coverage of all possible event sequences while maintaining a clear logical flow that matches how incidents actually develop in real-world scenarios.

Correct Answer: Binary success/failure outcomes of preventive measures

In Event Tree Analysis (ETA), branching points represent binary success/failure outcomes of preventive measures or safety barriers. This is correct because: - ETA is fundamentally based on binary logic - Each node represents a yes/no or success/failure scenario - Each branch shows what happens when a safety measure either works or fails Why other options are incorrect: Parallel sequences are not accurate as ETA follows a sequential path, not parallel paths. Continuous probability distributions do not represent ETA branching - the branches are discrete, not continuous. Stakeholder preferences do not determine branching points - these are based on objective system responses and safety measure outcomes.