Examining the Risk of Electric Shock Drowning (ESD) As a Function of Water Conductivity

Abstract

The press is full of articles discussing the risk of electric shock drowning (ESD). Per these publications, the risk of ESD is limited to current leakage in fresh water environments. Medical response and treatment of ESD are based on this generally held belief. There appears to be no research or simulation establishing the true bounds and risk of ESD as a function of water conductivity. ESD is theorized to occur when leakage current passes through the body causing uncontrollable muscle contraction. The common belief is that ESD can only occur in fresh water where the current will be directed through the body because of its greater conductivity than the surrounding fresh water. It is broadly believed that in salt water, the current will shunt around the body. The authors have tested this theory using the finite-element method in simulations of conductivity (with unit of seimens per meter or S/m) ranging from 0.005 S/m (pure water) up to 4.8 S/m (seawater). The results demonstrate that there is varying shunting through the body as water ranges from fresh to salt. Furthermore, the prevailing belief fails to consider that there is also a distinct current limiting affect that is inversely proportional to the conductivity of the water, which in turn acts to narrow the “zone of danger” as water conductivity is decreased. It is imperative that there be public education that supersedes generally held myth and such that electrical injury risk is minimized in both salt and fresh water environments.