Currents flowing through the human body: The numerical viewpoint

In case of direct or indirect contact with electrically energized parts, an electric current circulates through the body. When the magnitude and duration of the current through the heart exceed the ventricular fibrillation thresholds, the cardiac muscle starts uncoordinated contractions, greatly jeopardizing the life of the subject. Technical standards on electrical installations describe the protective measures against direct and indirect contact necessary to minimize the probability of inception of ventricular fibrillation. Safety considerations are based on experiments made in the past on animals, but the extrapolation of results to human beings is complex and rather questionable. The purpose of this study is to analyze the body factors that affect the distribution of currents passing through the human body with virtual anatomical models. A set of sixteen models of individuals is used to simulate different electric contacts. The use of virtual models of a diverse population (i.e. eight males and eight females, ten adults and six children) provides a statistical support to the results. The obtained heart-current factors, which take into account the current frequency, are compared with values present in literature. This paper provides a novel viewpoint on the problem, and supports the ongoing research activity and efforts to improve the electrical safety of persons.