NESC Standard C2-1997 itself does not describe specific requirements for sign legends or designs. But, it specifically references the ANSI Z535 sign, tag and label standards and leaves much of the explanation of sign design to Appendix B of the accompanying NESC Handbook. In the NESC Handbook, you will find a number of typical sign designs. However, Appendix B likewise points out that the underlying ANSI standards have also changed. As a result, sign designs are undergoing further modifications and you need to see the latest standards.

To aid you further, we list here what we believe are the most important sign design issues for substations in the NESC:

 • Section 110 A.1 for Substations: “A safety sign shall be displayed at entrances. For fenced electric supply stations, a safety sign shall be displayed on each side.”

 • Section 381 for Pad-mounts: “A prominent and appropriate safety sign should be visible when the first door or barrier is opened or removed.”

 • Section 217 A.2.a for Climbable Structures: “Readily climbable supporting structures...shall be posted with appropriate warning signs.”

 • Section 218 A.3 for Supporting Structures: “Supporting structures...[shall be] numbered so as to facilitate identification by employees authorized to work thereon.”

 • Section 411 D on Work Rules and Signs: “Permanent warning signs shall be displayed in conspicuous places at all entrances to electric supply stations, substations, and other enclosed walk-in areas containing exposed current-carrying parts.”

There is also mention of warning labels and signs in 112 B for Passageways; 124 C.1 for the Guarding of Live Parts; 146 B for Battery Rooms; and, 220 D for the Identification of Overhead Conductors.