This standard is a revision of American National Standard Y32.9-1962. It also supersedes the military standard MIL-STD-15-3@ 30 October 1961. The format has been modi?ed and minor changes have been made in the symbols in order to coordinate the industry and military standards. Appendix A shows revised and deleted symbols from both predecessor documents.The change in Section 2.@ Receptacles@ was based on the latest edition of the National Electrical Code@ ANSI C1-1971. The previous edition showed both grounded and ungrounded receptacles@ with the grounded ones indicated as the exceptions unless they are the majority of receptacles in the drawing. In this edition@ the requirement of the National Electrical Code for grounded receptacles is incorporated.This standard provides a basis for1) Showing the general physical location and arrangement of the sections of the required wiring system2) Identifying the physical requirements for various types of materials needed to provide the electrical installation in buildingsIn some instances@ the symbols may indicate the function or electrical characteristics of the system; however@ that is not their primary purpose. Such functions or characteristics are shown by the use of the graphic symbols for electrical diagrams@ as specified in American National Standard Y32.2-1970@ Graphic Symbols for Electrical and Electronics Diagrams (IEEE Std 315-1971).The required installation is shown on the drawing by the use of the various applicable outlet and equipment symbols@ together with interconnecting circuit or feeder run lines@ supplemented with necessary notations.In general@ basic symbols have been included in the symbol schedule. In some instances@ the use of numbers or letters of the alphabet drawn in@ or at the side of@ the basic symbol to identify a specific application of the symbol for a particular type or use of outlet may be required. In some instances@ the physical or electrical size of the item identified by the symbol will be noted to one side of it.