The popular but older standards: PMC 22.1-1981, Functional Diagramming of Instrument and Control Systems; ISA 5.2-1976, Binary Logic Diagram for Process Operation; and ISO 3511, Graphical Symbols for ...

Though the standard may make use of standard symbols now used for piping and instrument diagrams, logic diagrams, loop diagrams, mathematical works, and other documents, it is generally expected to be ...