Do metal objects such as mobile phones increase lightning risk?

Abstract

This study has been carried out to test two hypotheses; whether a small metal object such as mobile phones in possession of a human body increases the chances of a direct lightning strike and whether a similar object increases the chances of a side flash. Simulations were done in COMSOL Multiphysics for a metal sphere of radius 10 mm placed at the head level of a 2 m tall human being. A five-meter-tall cylindrical lightning target of resistivity 2.75 GΩ m and 10 nΩ m were considered. The influence of the side flash increases with the size of the metal object and also as its shape deviates from the spherical dimension. The outcomes of the study confidently discard the possibility of a metal object of practically viable size on a human body to influence the direct lightning attachment process. A metal sphere of radius about 22 m or a person of height 8.5 m is required for increasing the possibility of such a direct strike. Thus, the popular public concept is firmly rejected. However, the same metal object may significantly increase the side flash probability if the victim is close to the lightning struck object or inside an unsafe shelter.