Ground rods used for lightning protection systems must be not less than what length?

Ground rods used for lightning protection systems must be at least 8 feet in length to ensure proper grounding and effective dissipation of lightning energy. This length is specified in the National Electrical Code (NEC) as it helps to achieve a low-resistance connection between the ground and the lightning protection system. A proper grounding system is crucial for safety reasons; it prevents electrical surges from damaging structures and minimizes the risk of electrical fires.

Using rods shorter than 8 feet may not adequately provide the necessary path to dissipate lightning strikes, which could lead to counterproductive results in lightning protection. Therefore, the established standard of 8 feet is essential for safety, efficiency, and code compliance in lightning protection design.