Effective ground resistance of the human feet in high voltage switchyards

The ground resistance of the feet, which is an important factor that determines the current flow in the body of a person exposed to dangerous touch voltage in a high-voltage switchyard, is modified by the proximity of the two feet and the presence of the energized grounding grid below the feet. Based on the Thevenin approach, a general method for determining the effective ground resistance of the feet that takes into account the modifying factors is presented. The method is verified with the help of analog model study. Results show that in most practical situations the effect of the modifying factors can be ignored. The situations in which it is necessary to consider these factors are identified