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 Appendix A
PROCEDURE
1.
DIAGRAM DEVELOPMENT. The job order is received by the Master
Scheduler through the normal job order procedure, except that Job Phase
Calculation Sheets (Figure A-1) are included on those multicraft jobs
estimated to cost $5,000 or more. The Master Scheduler may request the Job
Phase Calculation Sheets on smaller size jobs when critical path scheduling is
desirable.
a. Job Description. A sample job (Figure A-2) demonstrates the
techniques and advantages of Critical Path Scheduling. This particular job
typifies complexities that confront Master Schedulers on large multicraft
jobs. This job was estimated to cost approximately $5,000, involved six work
centers, and required outside purchase as well as Navy stock materials.
b. Step List. A step is a specified unit of work that can be
accomplished without interference or interruption from any other work. The
Master Scheduler develops a Step List (Figure A-3) of normal operations from
each phase on the Job Phase Calculation Sheets, Figure A-1. The number of
steps, or self-contained units of work, that is in each phase will be
determined by the Master Scheduler by examining each task description. Figure
A-1 shows that in some instances a single task is a step, and in other
instances a step may consist of a number of tasks, or a step may be
subdivided. For example, Figure A-1 shows interior painting in five items:
The Step List regroups these into two steps: 9, paint ceiling, and 10, paint
walls. As discussed in paragraph 4d, these steps might be regrouped as: 9,
prepare ceilings and walls; 9a, prime ceilings and walls; 9b, paint ceilings
and sprinkler system; 9c, paint upper walls; and 10, paint dado. The degree
to which steps are combined, or subdivided, will depend upon the work directly
involved, the type and amount of related work involved, and the degree of
coordination required. After preparing the Step List, the Master Scheduler
should prorate to each step that percentage of the "total job phase time
hours" on the Job Phase Calculation Sheet that is contained in each step.
This will allocate the proper share of the craft preparation, allowances, and
travel time that is applicable to each step. Generally, prorating a phase
won't cause a problem; however, allow sufficient time in each step for the
applicable allowances. If desired, assistance can be obtained from the
Planners and Estimators in prorating these allowances to the steps. The
amount of total allocated hours for a step is divided by the number of
personnel in the crew assigned to that step. The quotient is the duration
time (clock time, calendar time, or crew time) for each step (Figure A-3).
There may be other steps not shown on the Job Phase Calculation Sheets that
should be considered, such as: direct procurement material lead time and
stock item material lead time. These are separate steps.
c. Arrow Diagram. An arrow diagram (Figure A-4) shows graphically
the interrelationships and interdependencies of the various steps in a total
job plan. Each step in the job is represented by an arrow. The arrow diagram
is simple in detail, but it does require some trial and error before the
proper relationships of the steps are established. The arrow diagram should
be constructed in accordance with the following criteria:
A-1
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