Element of Fault Tree Analysis Diagrams
Basic Elements of Fault Tree
FTA is a deductive analysis approach for resolving an undesired event into its causes. It is a backward looking analysis, looking backward at the causes of a certain event. It mainly consists of the following elements.
- Specific stepwise logic is applied in the process.
- Specific logic symbols are used to illustrate the event relationships.
- A logic diagram is constructed showing the event relationships.
Gates and fault events constitute the building blocks of a fault tree. The AND and OR gates are the two most commonly used gates in a fault tree diagram.
To illustrate the use of these gates, consider two events (called "input events") that can lead to another event (called the "output event"). If the occurrence of either input event causes the output event to occur, then these input events are connected using an OR gate. Alternatively, if both input events must occur in order for the output event to occur, then they are connected by an AND gate. Thus, gates are somewhat analogous to switches in an electrical circuit or two valves in a piping layout.
Refer to article: Fault Tree Symbols for more detailed illustrations of symbology: the building blocks of fault tree.
These building blocks can be drawn on hand or by software. Since they are standard symbology, there are solutions for predefined symbols for the convenience of users. Edraw offers such an easy solution so that users just need to drag and drop shapes to draw a fault tree diagram.
Fault Tree Diagram Software
Edraw Max is a second-to-none fault tree diagramming software with predefined symbols and rich templates. It enables even novice users to create fault tree diagrams to document business processes. Such diagrams help to find out measures to prevent failure by controlling its causes.
Fault Tree Template
The following fault tree diagram was created and included in the Edraw example gallery.