- An Activity Network Diagram is a diagram of project activities that shows the sequential relationships of activities using arrows and nodes.
- An activity network diagram tool is used extensively in and is necessary for the identification of a project’s critical path.
- An Activity Network diagram helps you to identify the Critical Path.
- The Critical path is the sequence of activities with the longest duration to complete. A delay in any of these activities will result in a delay for the whole project.
-
The essential technique for
using CPM is to construct a
model of the project that
includes the following:
- A list of all activities required to complete the project (typically categorized within a work breakdownstructure),
- The time (duration) that each activitywilltake to complete,
- The dependencies between the activitiesand,
- Logical end points such as milestonesor deliverable items.
Activity Network Diagram
How to make an Activity Network Diagram
-
Make a list of all the project's tasks.
- The first step is to compile a list of all the tasks neededto complete the project. -
Arrange in a chronological order
- The first step is to compile a list of all of the complete tasks needed to complete the proposed project. Arrange them in sequential order that is, in the order in which each task is executed.
- If one task depends on another, make sure that the dependent task is scheduled later than the one needed. To put it another way, if Task A requires the completion of Tasks B and C before it can be completed,put B and C in frontof TaskA.
- Draw tasks in parallel if they can be completed simultaneously. -
Calculate the Critical Path
- The Critical Path is the longest time through the entire project executing tasks in necessary order. This is important because the project will never complete quicker than the critical path. -
Analyze and check for efficiencies
- Look for ways to shorten your critical path. Reevaluate the task dependencies. Is there any way you can move tasks around to complete the project faster? What are the bottlenecks in your process? Is there any other way to complete tasks in parallel?
Activity Network Diagram Example
- Start -> Activity 1 -> Activity 2 -> Activity 3 -> Finish => 4 + 2 + 8 = 14 Hrs
- Start -> Activity 4 -> Activity 5 -> Finish => 6 + 10 = 16 Hrs -> Critical Path
- Start -> Activity 4 -> Activity 3 -> Finish => 6 + 8 = 14 Hrs