Fejlanalysetræer

Fejlanalysetræer, often translated as Fault Tree Analysis (FTA), are a top-down, deductive failure analysis technique used in system engineering and safety engineering. They begin with a specific undesirable event, such as a system failure or a safety hazard, and systematically identify all the potential causes that could lead to that event. The analysis is typically represented graphically as a tree structure.

The root of the tree represents the top-level undesired event. Branches extending from the root depict intermediate events or conditions that contribute to the top event. These intermediate events are linked by logical gates, most commonly AND and OR gates. An OR gate signifies that any of the input conditions can cause the output event, while an AND gate requires all input conditions to occur simultaneously for the output event to happen.

The leaves of the tree represent basic events, which are typically component failures or human errors that cannot be further broken down. Fejlanalysetræer are valuable for understanding the complex interactions between various failure modes within a system and for identifying critical failure points. They are used to calculate the probability of the top event occurring, assess the effectiveness of safety measures, and prioritize risk reduction efforts. The process involves defining the system, identifying the top event, listing contributing events, constructing the tree with appropriate gates, and performing quantitative or qualitative analysis.