REVISION - A revision means a modification of information in an existing  manual. Appropriate revision pages and related effectivity page lists will be provided when amending the basic document.

REISSUE - A reissue is a second or  subsequent  edition  of  a  manual which supersedes the preceding edition.

12.3 As a general rule, a revision shall be prepared  when  a  minor number  of   the  total  pages  of  the  manual is affected, Normally, when  pages  are  added  to  the  end  of  a  section,  or  to  the back  of a publication--not affecting pages  already  in  the manual--a revision  shall  always be prepared, However, when a point is reached where  the  accumulated  revisions  make distribution, filing and use of the manual difficult, a reissue is warranted,

12.4 When accumulated revisions, including back-up  pages,  total  over 60% of the total pages in the manual, a  reissue  of  the  manual should be prepared,

12.5 Revisions and/or additions shall be identified by a vertical black line or the letter "R" using automatic means, along the outside of the page (or gutter on two - column pages) opposite only  that  portion  of the printed  matter  that was changed, In the case of a revision  to  an illustration,  a black  vertical  line or a black hand may be utilized to call attention to the changed portion.

12.6 Each page containing changed or added material may bear the words "Revision  No. " followed by the revision date.

12.7 In a  reissue,  all  paragraphs,   illustrations,  tables,  and pages may be renumbered, as necessary, to  eliminate  all  number  suffixes and to establish correct sequence. All revision numbers and dates shall be removed from pages. All partial pages, and all miniature hand, shading, or bl ack- l i ne-in-margin change symbols shall be eliminated, The issue number and date must be clearly identified on the manual title page.