How does a PERT Diagram Handle Changes in Project Schedule?

A PERT (Program Evaluation and Review Technique) diagram is a graphical representation of a project’s tasks, dependencies, and timeline. It is used to visualize the flow of tasks and how they interrelate, as well as to help project managers determine the most efficient order for completing tasks and estimating the project’s duration. However, changes in the project schedule can sometimes occur, necessitating adjustments to the PERT diagram.

In this article, we will explore how PERT diagrams handle changes in project schedules and what steps project managers can take to ensure the accuracy and effectiveness of their PERT diagrams when changes occur.

Understanding Changes in Project Schedules

Project schedules are subject to change for a variety of reasons, including unexpected delays, changes in requirements, shifts in resources, and more. These changes can have a significant impact on the project timeline and overall completion date, and must be effectively managed to keep the project on track.

“The only constant in life is change,” - Heraclitus

To handle changes in project schedules, project managers must have a clear understanding of the reasons for the change and its potential impact on the project timeline. They must also have a plan in place for how to adjust the project schedule and PERT diagram to reflect the changes.

Common Reasons for Changes in Project Schedules

• Unforeseen events or circumstances
• Changes in project scope or requirements
• Delays in task completion
• Changes in resource availability
• Budget constraints

These are just a few of the many reasons why project schedules may change. Understanding the cause of the change is crucial in determining the best course of action for adjusting the project schedule and PERT diagram.

Adjusting the PERT Diagram to Reflect Changes

Once the reason for the change has been identified, the next step is to adjust the PERT diagram to reflect the updated project schedule. There are several ways to do this, including:

1. Updating task durations
2. Adding or removing tasks
3. Changing task dependencies
4. Re-sequencing tasks

Each of these adjustments will impact the overall project timeline, so it is important to consider the potential impact of each change before making any updates to the PERT diagram.

Updating Task Durations

One of the simplest ways to adjust the PERT diagram is to update the duration of a task. This can be done by simply extending or reducing the time allotted for a particular task based on the updated project schedule. When updating task durations, it is important to consider the potential impact on other tasks and the overall project timeline.

Adding or Removing Tasks

In some cases, changes in project schedule may require the addition or removal of tasks. This can be done by adding or removing tasks from the PERT diagram and updating the dependencies and task durations accordingly.

Changing Task Dependencies

Another way to adjust the PERT diagram is to change the dependencies between tasks. For example, if a task that was originally dependent on another task is now able to be completed independently, the dependency can be removed from the PERT diagram.

Re-sequencing Tasks

Finally, changes in project schedule may require re-sequencing the tasks in the PERT diagram. This can be done by rearranging the order of tasks based on the updated project timeline. When re-sequencing tasks, it is important to consider the potential impact on task dependencies, task durations, and the overall project timeline.

Using Gantt Charts to Visualize Changes in Project Schedules

While PERT diagrams are useful for visualizing the flow of tasks and dependencies, they can be limited in their ability to show the overall project timeline and schedule. Gantt charts, on the other hand, are designed specifically for this purpose and can provide a clear and concise view of the project timeline and schedule.

Online Gantt chart software like GanttPRO, Microsoft Project, Wrike, ClickUp, Monday.com, Smartsheet, and others, providea user-friendly interface for creating and updating Gantt charts. Project managers can easily add or remove tasks, update task durations, and visualize the impact of changes in project schedules on the overall project timeline.

Gantt charts also provide a clearer visual representation of task dependencies, making it easier to understand the interrelation of tasks and their impact on the project timeline. This can be especially useful when making updates to the project schedule, as it allows project managers to quickly see the potential impact of changes on the overall project timeline.

Conclusion

In conclusion, changes in project schedules are a common occurrence in project management and can have a significant impact on the project timeline and completion date. PERT diagrams are a useful tool for visualizing the flow of tasks and dependencies, but they can be limited in their ability to show the overall project timeline and schedule. Gantt charts provide a clearer visual representation of the project timeline and schedule and can be a useful tool for managing changes in project schedules.

Project managers must have a clear understanding of the reasons for changes in project schedules and a plan in place for how to adjust the project schedule and PERT diagram to reflect the changes. By using tools such as PERT diagrams and Gantt charts, project managers can effectively manage changes in project schedules and keep their projects on track.

Related posts

• Impact of Changes in Project Scope on a PERT Diagram
• Best Practices for Creating and Using PERT Diagrams in Project Management
• How does a PERT diagram show project dependencies?