This document provides an overview of Programme Evaluation & Review Technique (PERT) and Critical Path Method (CPM). It defines PERT as a technique used to plan, schedule, organize, coordinate, and control uncertain project activities, using three time estimates. CPM is defined as a method used to plan, schedule, coordinate, and control project activities, assuming fixed activity durations. The document outlines the key components, steps, and benefits of PERT and CPM, noting they are both useful for project planning but designed for different types of projects and environments.

1. Programme Evaluation &
Review Technique (PERT) &
Critical Path Method (CPM)
Submittedby:
RNAnkitaAshokKadam
PGDHA 2019-2020
Rollno. 04
GarwareInstituteof CareerEducation& Development
Hospital Planning & Designing

2. What is a Project?
 A project is an interrelated set of activities that has definite
starting and ending points and that result in a unique product
or service
 Cuts across organizational lines – they need varied skills of
different profession
 Uncertainties like new technology & external environment can
change the character of the project
 Personnel, materials, facilities etc. are temporarily assembled to
accomplish a goal within a specified time frame and then
disbanded
 Upon finish, a project releases lot of resources which were
engaged in execution of the project

4. Introduction
Definition of PERT
 PERT is an acronym for Program (Project) Evaluation and
Review Technique, in which planning, scheduling, organizing,
coordinating and controlling uncertain activities take place.
 The technique studies and represents the tasks undertaken to
complete a project, to identify the least time for completing a
task and the minimum time required to complete the whole
project..

6. Definition of CPM
 Developed in the late 1950s, Critical Path Method or
CPM is an algorithm used for planning, scheduling,
coordination and control of activities in a project.
 Here, it is assumed that the activity duration is fixed
and certain. CPM is used to compute the earliest and
latest possible start time for each activity.

8. History of PERT & CPM
 Critical Path Method (CPM)
– E I Du Pont de Nemours & Co. (1957) for construction of new chemical
plant and maintenance shut-down
– Deterministic task times
– Activity-on-node network construction
– Repetitive nature of jobs
 Project Evaluation and Review Technique (PERT)
– U S Navy (1958) for the POLARIS missile program
– Multiple task time estimates (probabilistic nature)
– Activity-on-arrow network construction
– Non-repetitive jobs

9. Components of PERT
 Predecessor event : It is an event that precedes some other
event; it can be single or multiple.
 Successor event : It is an event that immediately follows
some other event; it can be single or multiple successor
events.
 Optimistic time : It is the minimum possible time required to
complete the task anticipating that every event has occurred
better usually expected.
 Pessimistic time : This means the maximum possible time
required to complete the given task, expecting or assuming
everything goes wrong except the main catastrophes.

10. Components of PERT(cont.)
 Most likely time :The actual & the best time required to
complete the task assuming everything goes in a usual way.
 Expected time : The accurate or the actual time required to
complete the task. It is the most reliable time & valid time
estimated to complete a task.
Te = O + 4M + P / 6
 Float or Slack time : It is the amount of time that can be
floated without causing delay in the total completion of the
work.
 Critical paths : It is the longest possible & the actual total
time required to complete the full task.

11. Components of PERT (cont.)
 Critical total float activity : It is an activity that has total float
equal to zero. No float time is required in the critical path.
 Lead time : This refers to the time taken by the predecessor to
complete the task.
 Lag time : The earliest time taken by the successor event to
take place, which follows the specific PERT activity.
 Slack time : This refers to the measure of the max. time &
resources used in achieving the event.
 Fast tracking time : It means the time required to complete the
more critical activities at the same time.

12. Steps in PERT
Identifying the specific Objectives, activities &
milestones.
Determining the proper sequence of the activities.
Constructing a network diagram.
Estimating the time required for each activity.
Determining the critical path.
Updating the PERT chart as the project progresses

13. Why PERT/CPM
 Prediction of deliverables
 Planning resource requirements
 Controlling resource allocation
 Internal program review
 External program review
 Performance evaluation
 Uniform wide acceptance

14. Framework for PERT and CPM
 Define the Project. The Project should have only a single start
activity and a single finish activity.
 Develop the relationships among the activities.
 Draw the "Network" connecting all the activities.
 Assign time and/or cost estimates to each activity
 Compute the critical path.
 Use the Network to help plan, schedule, monitor and control the
project.

15. Blueprint of PERT/ CPM:
In any project work, an activity is performed & the
events in that activity are marked as milestones.
The blueprint or the network diagram of the PERT
model uses arcs & nodes to represent the activities
on the arcs & the events on the nodes

16. Guidelines for network diagram
1. Before an activity can begin, its preceding activities
must be completed.
2. Arrows indicate logical precedence.
3. Flow of the diagram is from left to right.
4. Arrows should not intersect.
5. Dangling should be avoided

18. PERT Chart
 A PERT chart is a graphical representation of the activities of
a project, showing the sequence that has to be performed
continuously.
 It has critical path of tasks that has to be finished in time.
A
B
C
D
E
F

20. BASIS FOR COMPARISON PERT CPM
Meaning PERT is a project management
technique, used to manage
uncertain activities of a
project.
CPM is a statistical technique
of project management that
manages well defined
activities of a project.
What is it? A technique of planning and
control of time.
A method to control cost and
time.
Orientation Event-oriented Activity-oriented
Evolution Evolved as Research &
Development project
Evolved as Construction
project
Model Probabilistic Model Deterministic Model
Focuses on Time Time-cost trade-off
Estimates Three time estimates One time estimate

21. BASIS FOR COMPARISON PERT CPM
Appropriate for High precision time estimate Reasonable time estimate
Management of Unpredictable Activities Predictable activities
Nature of jobs Non-repetitive nature Repetitive nature
Critical and Non-critical
activities
No differentiation Differentiated
Suitable for Research and Development
Project
Non-research projects like
civil construction, ship
building etc.
Crashing concept Not Applicable Applicable

22. Benefits of PERT/CPM
 Enables to determine the exact time of completion of the
task.
 Completion of work is possible before the time.
 Critical paths activities specify the main impact in
completion of activities in time.
 Slack time can be noted out early.
 Entire project can be organised & used for decision making.

23. Benefits of PERT/CPM(cont.)
 Prevents overlapping of activities, creates better understanding
the task activities.
 Helps to identify early start, late start & the slack time activities.
 Identifies the accurate critical path visible & clear to all.
 Helps to prevent loss of money, material & time.
 Allows the management to economically use the resources,
estimate time management & evaluate the work done in time.

24. Limitations of PERT/CPM
 Expert guidance is always needed for the proper judgement of time. A
highly knowledgeable & skilled person is needed to carry out estimation
time.
 It will be difficult to categorize the activities if there are more than
hundreds or thousands of them.
 Mere guess or approximation of time estimate can lead to errors in
evaluation of time during work.
 PERT uses beta distribution probability, but the actual time distribution may
be different.
 The PERT chart is usually very large & requires several pages for printing. It
also needs a special signed paper.
 Before planning a PERT chart, one needs to do a proper planning to estimate
the time frames for each activity.

25. conclusion
The difference between these two project management tools is
getting blurred as the techniques are merged with the passage
of time. That is why, in most projects, they are being used as a
single project. The primary point that distinguishes PERT from
CPM is that the former gives the extreme importance of time,
i.e. if the time is minimized, consequently the cost will also be
reduced. However, cost optimization is the basic element, in
the latter.

27. References
Textbook of Management in Nursing
Education : edition 3 by author I.Clement
Textbook of Management in Nursing
Education : edition 3 by author Vati
Google References
 Slideshare