Earthing rods improve earthing systems when driven into low resistivity soil layers. Due to the proximity effect the rule of thumb is earth rods should be separated by at least their driven length. Rods may be encased in concrete to lower their resistance. Equations are provided for hand calculations and these have been validated with numerical software.

Direct lightning strikes to substations causes physical damage and poses hazards for people.

There are two reasons, according to the standards, why crushed rock or gravel is laid in substations, as explained in this article.