Document is a guide to the application, operation and Maintenance of all types of High-Voltage fuses and associated equipment covered by the C37.4X series of standards. The project will revise approximately 20% of the document, while retaining the original document scope. [Original Scope - Revise/update scope, make improvements, and expand application to cover other devices (specifically full-range fuses, capacitor fuses, expulsion fuses in enclosures).] The standard provides use guidance on fuses and associated equipment. The proposed revision is to clarify and expand certain areas. Some of these were identified by comments to the vote on the last revision of the standard, while others have been identified by user feedback since that date. Revision Standard - Superseded. Information on the application, operation and maintenance of high-voltage fuses (above 1,000 V and through 169 kV), distribution enclosed single-pole air switches, fuse disconnecting switches, and accessories for use on ac distribution systems is provided. These include enclosed, open, and open-link types of distribution cutouts and fuses; distribution current-limiting fuses; distribution enclosed single-pole air switches; power fuses, including current-limiting types; outdoor and indoor fuse disconnecting switches; fuse supports, mountings, and links, all of the type used exclusively with the above; and removable switch blades for certain products among the above. This guide is one of a series of complimentary standards so arranged that this guide plus two other standards apply to all devices, while one or more of the other standards provides additional specifications for a particular device. For each device, IEEE Std C37.40-2003 and IEEE Std C37.41-2000 plus the standard(s) covering that device constitute a complete set of standards for each device. In addition to this application, operation and maintenance guide which covers all of the above devices, additional operation, classification, application, and coordination information for current-limiting fuses can be found in IEEE Std C37.48.1-2002, a "tutorial" style document.