During construction, why are grounding electrodes often established as building footings and foundations are installed?

Establishing grounding electrodes as building footings and foundations during construction is considered inherent because the grounding system must be integrated into the structure from the beginning. This integration is essential to ensure that the grounding system functions effectively as part of the overall electrical safety system of the building.

Footings and foundations provide a stable and permanent connection to the earth, fulfilling the requirement of grounding electrodes as specified in the National Electrical Code (NEC). By incorporating grounding electrodes into the structural components, the system not only benefits from the conductive properties of the earth but also becomes a part of the building's structural integrity, reducing the risk of disconnection or damage during future renovations or constructions.

The other terms used in the options, such as essential, incidental, and necessary, do not capture the foundational and intrinsic nature of how grounding is tied closely with the construction process. Grounding electrodes being part of the building’s footings and foundations is fundamental to ensuring electrical safety, which makes the relationship between construction and grounding electrodes inherently critical.