This Standard represents the progress made to date in evolving graphical symbols for use in preparation of logic diagrams for systems of binary-state devices. The Standard contains two alternate but overlapping sets of symbols. Since agreement on a common set of symbols could not be obtained, no preference is implied between the two sets presented herein. This represents a solution that seems best under circumstances that presently prevail. It is anticipated that the Standard will be reviewed at the Task Group level at regular intervals, and eventually agreement will be sought for a set of graphical symbols based on a common symbology. It is hoped that groups that have not been represented heretofore will participate at Task Group level in the preparation of future revisions.

This Standard sets forth principles governing the formation of graphical symbols for logic diagrams in which connections between symbols are generally shown with lines. Definitions of logic functions, the graphical representations of these functions, and examples of their application are given. 1.2.1 Two different but overlapping sets of graphical symbols are presented in this Standard: Uniform Shapes and Distinctive Shapes. For some functions there are different symbols in the two sets; for others the symbol is the same in both sets. Symbols from the non-overlapping parts of the two sets are not permitted on the same logic diagram. 1.2.2 This Standard defines the requirement for logic diagrams. The presentation, in some cases, extends beyond the area of logic functions in order to preserve the context of symbology relating to logic diagrams

This Standard establishes graphical symbols specifically designed for use in the preparation of logic diagrams for systems of two-state devices.