The minimum length allowed for driven ground rods under normal conditions is what?

The minimum length allowed for driven ground rods under normal conditions is 8 feet. This requirement is based on the National Electrical Code (NEC), which specifies that grounding electrodes must be properly sized to ensure sufficient electrical contact with the earth to effectively dissipate electrical faults. An 8-foot length provides a greater surface area for contact with the soil, improving its ability to conduct electricity safely. This length is crucial for grounding systems, as it helps maintain safety and reliability in electrical installations.

Shorter ground rods may not achieve the required grounding effectiveness, particularly in areas with high soil resistance, which could compromise the protection provided by the grounding system. Therefore, using an 8-foot ground rod is a standard practice to ensure proper grounding under normal conditions.