The Critical Path Method

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1 The Critical Path Method Presented by Antonio Prensa, MBA, PMP, CCP, CSTE for Project Management Institute Puerto Rico Chapter June 2, 22 San Juan, Puerto Rico

2 "I believe that this nation should commit itself to achieving a goal, before this decade is out, of landing a man on the moon..." - John F. Kennedy, May 27,1961

3 On July 2, 1969, just eight years after Kennedy's speech, Apollo 11 landed two men on the moon. This achievement was possible only with careful production planning that included the critical path method. NASA used the critical path method to help determine an efficient schedule for the tasks that led to the moon landing.

4 Discussion Topics Background Some questions about the project What is the Critical Path Method (CPM)? Why the CPM? How to use the CPM? Questions and Answers

5 Background The critical path method (CPM) was invented by project managers in the early 195's. The US Navy adapted and improved it to manage the Polaris missile project in the late 195's

6 Some questions about the project How long will the entire project take to complete? Which activities determine total project time? Which activity times should be shortened, if possible, or in other words, how many resources should be allocated to each activity?

7 What is the CPM? Critical Path Method (CPM), is a procedure for using network analysis to identify those tasks which are on the critical path: ie where any delay in the completion of these tasks will lengthen the project timescale, unless action is taken. For all tasks off the critical path, a degree of tolerance is possible (eg. late start, late completion, early start, etc.). Network charts and CPM analysis used to be carried out by hand. Software is now available which requires the user only to enter the tasks, duration of each task and dependencies upon other tasks; a network chart and CPM is then automatically created.

8 Why the CPM? The CPM formally identifies tasks which must be completed on time for the whole project to be completed on time Identifies which tasks can be delayed for a while if resource needs to be reallocated to catch up on missed tasks It helps you to identify the minimum length of time needed to complete a project The CPM determines both the early start and the late start date for each activity in the schedule.

9 How to use the CPM? Project Network Diagram Any schematic display of the logical relationships of project activities

10 How to use the CPM? List List the the activities And And relationships Create Create a start start node node Draw Draw arrows arrows from from Start Start node node to to the the First First activity s node node Sequentially Arrange all all Activities from from Start Start Repeat Repeat process process from from successors for for all all activities Double Double check check for for missed missed relationships

11 How to use the CPM? Early Start (ES) Early Finish (EF) Task duration Late Start (LS) Late Finish (LF)

12 How to use the CPM? Task ID Duration Dependency A 7 B 3 C 6 A D 3 B E 3 D,F F 2 B G 3 C H 2 E,G

13 How to use the CPM? S A C G (7) (6) (3) H (2) F B D (3) (3) 6 9 E (3) 3 5 F (2)

14 How to use the CPM? S A C G (7) 7 7 (6) (3) H (2) 18 F 7 B D (3) 1 1 (3) E (3) F (2) 13

15 How to use the CPM? S 7 A B C D F G (7) 7 7 (6) (3) (3) 1 1 (3) (2) E (3) H (2) 18 F

16 Summary Critical Path Analysis is an effective and powerful method of assessing: Tasks which must be carried out Where parallel activity can be carried out The shortest time in which a project can be completed Resources needed to achieve a project The sequence of activities, scheduling, and timings involved Task priorities

17 Do you need more information? Project Management:A systems approach to Planning, Scheduling, and Controlling Harold Kerzner, Six edition. Project Management: A Managerial Approach Jack R. Meredith, Samuel J. Mantel, Fourth Edition. Web Search Engine key word: The Critical Path Method or The CPM.

18 Contact me at: Antonio Prensa / Phone: (787) ext. 3725

19 The Critical Path Method Presented by Antonio Prensa, MBA, PMP, CCP, CSTE for Project Management Institute Puerto Rico Chapter June 2, 22 San Juan, Puerto Rico

A convenient analytical and visual technique of PERT and CPM prove extremely valuable in assisting the managers in managing the projects.

A convenient analytical and visual technique of PERT and CPM prove extremely valuable in assisting the managers in managing the projects. Introduction Any project involves planning, scheduling and controlling a number of interrelated activities with use of limited resources, namely, men, machines, materials, money and time. The projects