Our system involves passing a small amount of electric current through the earth’s surface to determine its resistance. This is crucial for designing safe earthing systems. In places like substations, the safety criteria for touch and step potentials rely heavily on soil resistivity. For other settings like industrial or residential buildings, the acceptable grounding resistance and current density on the electrode surface depend on soil resistivity.

Accurate measurements are essential for precise design. According to standards, the soil conditions within 3 to 4 times the mat’s longest dimension impact current dissipation. Since soil isn’t uniform in depth and breadth, accuracy in measuring soil resistivity is vital for reliable designs.

Soil resistivity can be measured in a variety of methods. Electrical profiling is the best approach for assessing soil resistivity for the design of earthing and safety requirements. By injecting a current, and monitoring the voltage drop at different spacing, without any excavation electrical profile of the soil can be done.