Page 291 - The Handbook for Quality Management a Complete Guide to Operational Excellence

278 C o n t i n u o u s I m p r o v e m e n t D e f i n e S t a g e 279

Immediately Latest Time – Minimum =
Event Following Event Activity Time Latest Time
13 — — 44
12 13 44 - 6 38
11 12 38 - 0 38
10 13 44 - 2 42
9 12 38 - 5 33
11 38 - 4 *
8 10 42 - 9 33
7 9 33 - 8 25
6 8 33 - 7 26
5 8 33 - 0
7 25 - 5 20
4 7 25 - 7
6 26 - 6
5 20 - 4 16
3 4 16 - 10 6
2 3 6 - 4 2
1 2 2 - 2 0

Table 13.4 Calculation of Latest Completion Times for House Construction Example

Slack time for an event is the difference between the latest and earliest
times for a given event. Thus, assuming everything else remains on schedule,
the slack for an event indicates how much delay in reaching the event can
be tolerated without delaying the project completion. Slack times for the
events in the house construction project are shown in Table 13.5.

Event Slack Event Slack
1 0 - 0 = 0 7 25 - 25 = 0
2 2 - 2 = 0 8 33 - 29 = 4
3 6 - 6 = 0 9 33 - 33 = 0
4 16 - 16 = 0 10 42 - 38 = 4
5 20 - 20 = 0 11 38 - 37 = 1
6 26 - 22 = 4 12 38 - 38 = 0
Continued … Continued … 13 44 - 44 = 0

Table 13.5 Calculation of Slack Times for House Construction Events

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