Introduction To Print Reading
DOE-HDBK-1016/1-93
INTRODUCTION TO PRINT READING
Changes
There are two common methods of indicating where a revision has changed a drawing that
contains a system diagram. The first is the cloud method, where each change is enclosed by a
hand-drawn cloud shape, as shown in Figure 4. The second method involves placing a circle (or
triangle or other shape) with the revision number next to each effected portion of the drawing,
as shown in Figure 4. The cloud method indicates changes from the most recent revision only,
whereas the second method indicates all revisions to the drawing because all of the previous
revision circles remain on the drawing.
The revision number and revision block are especially useful in researching the evolution of a
Figure 4 Methods of Denoting Changes
specific system or component through the comparison of the various revisions.
Rev. 0
PR-01
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