When you’re dealing with scheduling for the PMP Certification Exam, you will need to know about conducting a forward pass. The forward pass will tell you what the earliest dates are that activities can start and finish, based on the network logic. Here are the steps to conduct a forward pass:
Set the early start for the first activity (“Activity A”) or activities to 1.
Scheduling software assumes that an activity starts at 8 a.m. and is complete at 5 p.m. on its due date. Therefore, the next activity starts the next morning at 8 a.m.
Add the duration of the activity to the early start and then subtract 1.
Now you have your early finish date.
In this example, Activity A starts at Day 1. You add the duration of 5 to Day 1, and then subtract 1, giving you an early finish date of Day 5.
Always subtract 1 from the early start plus the duration because you start on Day 1, not Day 0.
Add 1 to the early finish to determine the early start of the immediate successor activities.
For this example, the early start of Activity B is 6. However, the early start of Activity C is 4 because there is a two-day lead. The early start of C would have been 6, but you subtract 2 days from 6 because of the two-day lead, and that gives you an early start of 4.
To continue along with C, you add the duration of 4 to the early start of 4, subtract 1, and get an early finish of 7.
Going to Activity B, you add the early start of 6 and the duration of 3, subtract 1, and get an early finish of 8. There is a two-day lag between B and D, so Activity D starts two days after B finishes. This means that D will start on Day 11.
Continue in this fashion until you reach the end of the network.
Note these areas of interest in this diagram:
Activity F has the same early start as Activity E because there is a start-to-start relationship. Activity F can start after Activity E starts.
Activity G and Activity H have a finish-to-finish relationship. This means that Activity H can finish after Activity G finishes.
Activity D and Activity E both have to finish before Activity G can start. Activity D has an early finish of 16, and Activity E has an early finish of 14. When there is a path convergence in a forward pass, the highest number always carries forward.
After you finish calculating your forward pass, you will see the earliest finish date. This is the soonest the project can finish, given the information available. For this example, the early finish date is 22 days.