Computational Dosimetry on Contact Currents from Charged Human Body

Contact current, defined as indirect effects of electromagnetic fields, flows a human body when contacting with an object such as a metal structure at a different electric potential, and may stimulate muscle and peripheral nerve. Thus, numerical analyses of electric fields induced by contact currents in a human body have been performed. Computational methods and evaluations of effects of transient field associated with contact currents have not yet been understood sufficiently. In the present study, we have simulated induced electric field in a human body due to contact current with dispersive FDTD method incorporated with a Japanese adult male model developed at National Institute of Information and Communication Technology. We compared FDTD calculations of body surface magnetic fields caused by contact current with measurements to validate our FDTD modeling, and then calculated induced peak electric field. As a result, we found that calculated and measured result of body surface magnetic fields are in fair agreement, confirming the validity of our FDTD modelling. The induced electric field becomes higher around the arm, while relatively lower in the central nerve systems.