About Event Diagram

In an RCA, analyzing data involves compiling the information that has been collected so far in the Root Cause Analysis and representing it visually to facilitate discussion. An Event Diagram is an organizational tool that you can use to diagram a sequence of events, which are possible causes of a failure event.

Details

The Event Diagram lets you represent visually the events that are associated with a failure and the cause-and-effect relationships that may have led to a failure event. The Event Diagram depicts how the events affect each other and enables you to identify possible work process issues. Each event is represented by a labeled icon, called a node. You can add nodes to the Failure Event node that represent components of the Root Cause Analysis. For example, if you define the Failure Event node as a fire, in the Event Diagram you can add to the Failure Event node upstream nodes that depict the chain of events that preceded the failure event.

The following list provides the types of nodes that you can use in an Event Diagram:

Node Icon	Node Name	Can be used to represent...
	Start/Finish	A step that marks the starting point or the ending point of the event.
	References	A printed document or report.
	Process	A single step or an entire sub-process within a larger process.
	Decision	A decision or branching point.
	Operation	Material or information entering or leaving the system, such as customer order (input) or a product (output).

You can create connections between the nodes in the Event Diagram to establish a relationship between the nodes. Each node in the diagram canvas has two ports that are used for connecting nodes to another node. Each port is designated by a circle on the right and left of the node. You can initiate a connection only from right circle (output port) of the predecessor node to the left circle (input port) of the successor node. You can create as many connections as you need to build the Event Diagram. More than one connector can be attached to the same port of a node, allowing you to create parallel events. As you connect the nodes to build the Event Diagram, links are created between the items using a predecessor-successor relationship definition that exists between them.

Note: The predecessor is the node that precedes the node that is currently selected in the Event Diagram. The successor is the node that succeeds the node that is currently selected in the Event Diagram.