On the possible variation of the lightning striking distance as defined in the IEC lightning protection standard as a function of structure height

The effect of structure height on the lightning striking distance is estimated using a lightning strike model that takes into account the effect of connecting leaders. According to the results, the lightning striking distance may differ significantly from the values assumed in the IEC standard for structure heights beyond 30 m. However, for structure heights smaller than about 30 m, the results show that the values assumed by IEC do not differ significantly from the model's predictions based on a striking model taking into account the effect of connecting leaders. However, since IEC assumes a smaller striking distance than the ones predicted by the adopted model one can conclude that the safety is not compromised in adhering to the IEC standard. In this respect, further analysis making use of lightning strike models developed by other authors is recommended.