and labor hour availability. However, step 3 now becomes critical rather than
step 4; but by doubling the step 3 crew, step 4 would again become critical.
Because step 11 cannot start until step 9 is completed, the initial time for
step 11, 19.5 hours, is not critical compared to step 10 (when triple crewed)
at 21.2 hours. However, because of the nature of operations such as light
fixture installations and wall painting, some interference among personnel
might occur. By tripling the crew on step 11 this difficulty would be avoided.
d. Variations. A more detailed study of steps 9, 10, 12, and 13 shows
another possible variation. As shown in Figure A-6, radiators and water
coolers (steps 12 and 13) are to be installed while ceiling and walls are
being painted (steps 9 and 10). Questions involved here are:
(1) Are radiators to be painted?
(2) How can walls near radiators and water coolers be painted at the
same time plumbers and pipefitters are working?
(3) IS it desirable to paint walls near water coolers and radiators
prior to, or at the same time as, the ceilings?
As suggested in paragraph 1b, steps 9 and 10 might be subdivided and regrouped
into: 9, prepare ceilings and walls; 9a, prime ceilings and walls; 9b, paint
ceiling and sprinkler system; 9c, paint upper walls, and 10, paint dado. This
arrangement would minimize spotting wall because different paint colors would
be used. Also step 10 could be subdivided into two steps; 10a, paint dado
behind radiators and water coolers; and 10b, paint balance of dado. This
latter arrangement would, however, change the `critical path and increase the
total shop duration time. Another variation, which-would not change the
critical path or the shop duration time, would be to subdivide step 9c so that
steps 9c and 10 would read: 9c, paint upper wall in area of radiators and
water coolers; 9d, paint dado in area of radiators and water coolers; 9e,
paint balance of upper wall; and 10, paint balance of dado. Electric
fixtures, radiators, and water coolers would then be installed upon completion
of step 9d.
e. Final Critical Path. Figure A-6 assumes that all improvements in the
critical path have been made with minimum effort and expense.
f. Final Step List. When the Master Scheduler is satisfied that the best
critical path has been developed, a Final Step List is prepared (see Figure
A-8) with the final crew assignments, revised duration time for each step, and
any applicable information for scheduling.
g. Preparation of Schedule. The transition from the Final Step List,
Figure A-8 and final critical path, Figure A-6 to the Job Schedule, Figure
A-9, is made by means of a Job Schedule Bar Chart, Figure A-7.
(1) Job Schedule Bar Chart. The chart is divided into weeks of five
workdays. (If overtime is used in the critical path, the chart should be
arranged to show the overtime effort). Steps may be listed in sequence of
step numbers and each bar (step) measured in duration time (in hours) for each
step as taken from the Final Step List, Figure A-8. Critical path steps
should be plotted first and in critical path sequence. From the Final
Critical Path, Figure A-6, step 4 would be plotted first because the job is