forward pass notation
The goal of the forward pass is to determine the earliest time that an event could take place. For example, what is the earliest that a project or activity might be started and finished?
To show the data on the forward pass, two additional elements are added to the precedence diagram picture. The first element is the duration of each activity. The duration of the activity should be shown in the center of an activity's node.
The second elements added to a Precedence Diagram for the forward pass are the "Early Time" boxes. The Early Time boxes are placed within the activity node. There are no standards for the placement of these Early Time boxes, therefore, a legend must be provided with a Precedence Diagram to show where these Early Time boxes are placed. Early Time boxes are typically placed in one of two locations. The first is on the left-hand side of the activity node. The second is in the top left and right corners of the activity box. The CPM tutor will use the convention shown in the diagram below.
These Early Time boxes refer to the Early Start and Early Finish of each activity. Unlike the "event times" of the arrow diagram, which are attributes of nodes, the Early Times of the Precedence Diagram are activity-specific.