W. Va. Code § 21-3-3a: National Electrical Code minimum standards.

In every factory, mercantile establishment, mill or workshop, the installation, alteration, repair, moving, removal, maintenance and conversion of all electrical wiring and apparatus and equipment shall be done in accordance with the minimum standards of safety and construction as set by the copyrighted National Electrical Code, as promulgated, from time to time, by the national fire protection association.