American National Standard NOAO
Electrical and Electronics Diagrams Including Reference Designation Letters Sponsor ANSI 1975 CSA Z99ยท1975 IEEE Std 315 1975 Revision of ANSI 1972 CSA Z99 1972 IEEE Std 315 1971 IEEE Standards Coordinating Committee 11 Graphic Symbols Secretariat for American National Standards Committee Y32 American Society of Mechanical Engineers Institute of Electrical and