Theme 3.3.4 - Critical Path Analysis

Question 1

What is critical path analysis?

Answer 1

Critical path analysis (CPA) is a project management technique that identifies the sequence of essential tasks that determine the minimum project duration

Question 2

Why is CPA useful?

Answer 2

By focusing on critical tasks, project managers can optimise resource allocation and minimise delays.
Helps identify the most important tasks that need to be completed to finish a project on time

Question 3

How to calculate the critical path?

Answer 3

• Define the project scope
• List all the project tasks
• Estimate the duration of each task
• Identify dependencies
• Plotting the tasks on a network diagram

Question 4

Advantages of critical path analysis

Answer 4

• Figures out the activities which can run parallel to each other
• Helps identify most critical elements of the project
• Shows activities and their outcomes
• Gives a fair and concise procedure of documenting the project
• Provides a clear approach of communicating project plans, time and cost performance

Question 5

Disadvantages of critical path analysis

Answer 5

• Scheduling of personnel is not handled by CPA
• Sometimes is difficult to estimate the completion time of an activity
• CP is not always clear on complex projects
• CPA does not handle plant or resource allocation
• The critical path must be calculated precisely

Question 6

What is Earliest Start Time (EST) and how do you calculate it?

Answer 6

EST is the soonest any task can begin, based on the completion of preceding tasks

• Start by assigning an EST of 0 to the first task
• Move through the network, adding the time required for each task to the EST of its preceding task

Question 7

What is Latest Start Time (LST) and how do you calculate it?

Answer 7

LST is the latest a task can begin without delaying the projects completion
- Start from the end of the project, we assign the projects due date as the LFT for the final task
- Move backwards through the network, subtracting the task duration from the LFT to find the EST for each preceding task

Question 8

What is a critical path?

Answer 8

Critical path is the longest sequence of activities that must be completed one after the other

Question 9

Why is the critical path important?

Answer 9

• Determines the shortest possible time to complete the entire project
• If any activity on the critical path is delayed, whole project will be delayed