This document discusses Planning and Control Programme Evaluation and Review Technique (PERT). It defines PERT as a method to analyze the time required to complete a project using a graphical representation called a PERT chart. A PERT chart shows the sequence of activities, with circles marking the start and end of tasks (nodes) and arrows marking the tasks. It also discusses the components of a PERT model including predecessor/successor events, optimistic/pessimistic/likely durations, expected time, slack, and the critical path. The document outlines the steps to PERT planning and benefits like determining the completion date and identifying the critical path, as well as limitations such as the need for time estimates.

1. Planning and control
Programme Evaluation and Review
Technique – PERT
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2. Introduction
• In this method, the time required to complete each task or
activity is identified and then the minimum time required in
completing the total project is calculated.
• It is based on network analysis.
• This model helps to reduce the patients hospital stay by
judging beforehand the actual care time, manpower, money
and material required.
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3. Definition
• PERT is a method to analyze the time required to
complete a project.
• A PERT chart is a graphical representation of the
activities of a project, showing the sequence that has to
be performed continuously. This chart helps to focus
only on the needed activities and omit the unwanted
ones.
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5. Concept
• The duration of activities is measured by 3 parameters: most optimum
duration, most likely duration and most pessimistic duration.
• The CIRCLES mark the beginnings and end of tasks to be done in the project. Also
called NODES.
• The ARROWS are the tasks.
• The NUMBERS after the task names are the DURATION of the task.
• When a node has two or more task branching from it , means that those tasks can
be done concurrently.
• When a node has incoming arrows, it means that the incoming task must be
completed before progressing to the next node.
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6. Components of PERT model
• Predecessor event : it is an event that precedes some
other event.
• Successor events: it is an event that immediately follows
some other event.
• Optimistic time (O): it is the minimum possible time
required to complete the task anticipating that every
event has occurred better than usually expected.
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• Pessimistic time (P): this means the maximum possible time required to
complete the given task, expecting or assuming everything goes wrong
except the main catastrophes.
• Most likely time (M): the actual and best time required to complete the
task assuming everything goes in a usual way.
• Expected time or the very best time (TE): the accurate or the actual time
required to complete the task. TE = (O+4M+P)/6

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• Slack : it is a measure of the excess time and resources available in achieving an
event. There are 3 types of slack – Positive slack – indicate ahead of schedule:
Negative slack – indicate behind schedule : zero slack – indicate on schedule.
• Float /Slack time :it the amount of time that can be floated without causing
delay in the total completion of a project
• Free float – it is the excess time and resources available in achieving an task.
• Total float - it is the excess time and resources available in achieving an whole
project .

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• Critical path – it is the longest possible continuous pathway
taken from the initial event to the terminal event.
• Critical total float activity – it is an activity that has total float
equal to zero.
• Lead time – it is 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.

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• Fast tracking time – it means the time required to
complete more critical activities at the same time.
• Crash critical path – this means shortening the duration
of critical activities.

11. Steps involved in PERT planning process
• Identifying the specific activities and 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 programme progresses.
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12. Benefits of PERT
• Enables to determine the exact date of completion of the task.
• Completion of work is possible before the specified time.
• Critical path activities specify the main impact in completion of
activities in time.
• Slack time can be noted out early.
• Entire project data can be organized and used for decision making.
• and evaluate the work done in time.
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Contd..

13. Benefits contd…
• Prevents overlapping of activities, creates better understanding of the task
activities.
• Helps to identify early start, late start, and slack time activity.
• Identify the accurate critical path visible and clear to all.
• Helps to prevent loss of money, material and time.
• Allows the management to use the resources, estimate time management
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14. Limitations of PERT
• Expert guidance is always needed for proper judgment of time.
• It will be difficult to categorize the activities if there is 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 distribution may be different.
• PERT chart is usually very large and requires several pages for printing.
• Before planning a PERT chart, one needs to do a proper planning to estimate the time
frames for each activity.
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15. Gantt chart / activity plan 8/27/2020Anju George
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16. Definition
• It is defined as a graphical device that illustrates the tasks,
machines, personnel and resources used to complete a
task. It is always done on a calendar oriented grid.
• Gantt charts are used in nursing field to represent
mortality & morbidity rates and also indicate duty rosters.
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18. Components of Gantt chart
• It has a horizontal bar with a open triangular drawing showing the
start and finish date of a project.
• Horizontal axis – represents the time scale expressed as absolute
time from the start of the project to its end.
• Vertical axis – it represents the present point in time. Vertical lines
are indicated to denote progress and completion. It has a open start
triangle and finish triangle in vertical line that helps everybody to
understand progress and end of the project schedule.
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• Broken lines – these indicate gap or slippage times
during the project schedule.
• Diamond symbol - it indicates rescheduled work.

20. Marking in the Gantt chart
• Vertical marker indicates the present point in time
• Activity as it progresses, is shown by shading the bar
• At one glance we will come to know about the progress of
any activity
• Milestones are represented in the chart
• Color codes are used for certain specific task
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21. Advantages
• Excellent tool to communicate with population around the world
• At a single glance, work done can be analyzed quickly through the
breakdown structure.
• It is used as a reporting tool for larger projects
• It gives cost, time and scope of the project
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22. Disadvantages
• It cannot effortlessly display more than 30 activities.
• It is valuable only for short projects
• Chart can communicate only little information at a time
• Magnitude behind the schedule is easily miscommunicated, since it
doesn't represent full size of the project
• It is not suitable for most computer displays
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