Which grounding method is preferred when work is to be performed on deenergized lines?

The preferred grounding method when work is to be performed on deenergized lines is EPZ grounding, which stands for Equipotential Zone grounding. This method is utilized to provide a safe working environment by ensuring that all conductive parts are at the same electrical potential, minimizing the risk of electrical shock.

EPZ grounding involves the use of a conductive grid or mat, which connects the ground to various conductive elements of the work area. By maintaining an equal potential across the work zone, it helps protect workers from step and touch voltage hazards during maintenance tasks. This method is particularly effective because it accounts for various factors that can influence potential differences, such as nearby energized equipment and discharge paths.

Other grounding methods, while useful in certain contexts, do not provide the same level of safety for personnel working in close proximity to deenergized lines. For instance, phase grounding is often used to secure the lines themselves but does not address the safety of the workers' environment. Metallic grounding can effectively dissipate stray voltage but may not establish a uniform potential over a work area. Flexible grounding offers adaptability for various conditions but lacks the comprehensive safety that EPZ grounding provides for personnel.