Page 220 - E2 Integrated Workbook STUDENT 2018

Chapter 15

 The nodes also contain information on two times: The earliest event time (EET)
and the latest event time (LET).

EARLIEST EVENT
TIME (EET)

NODE
IDENTIFIER

LATEST EVENT
TIME (LET)

 All activities start and finish with nodes.

 The diagram is drawn and read from left to right.

 The activities on the critical path are identified with a double line.

3.3 Drawing a network diagram

 First draw a rough diagram to get the basic shape.

 Add in the durations for each activity.

 Once the network has been drawn, calculate the EET and LET for each node.

 To calculate the EET, work left to right. Take the EET from the previous node
and add this to the duration of the activity. Where you have a choice of EETs,
always select the highest.

 To calculate the LET, work right to left. Take the LET from the previous node
and deduct the duration of the activity. Where you have a choice of LETs,
always select the lowest.

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