Evaluating the Lightning Protection System Design of the Zalongo Monument in Greece based on Stochastic Modeling of Lightning Attachment

The necessity of installing an LPS at the Zalongo monument in Greece is evaluated. Two cases of isolated LPS are examined with respect to the efficiency of their air terminal. Both passive and non-conventional air terminals are evaluated considering the same location of installation and height; the non-conventional air terminal (ESE) is currently installed in the monument. A stochastic lightning attachment model is employed to estimate lightning incidence to the monument and evaluate the efficiency of the air-termination systems. The model considers the physical processes involved in lightning attachment following a probabilistic approach. Based on the model, direct lightning strikes to the monument are obtained; these may explain the photographically recorded damages caused by lightning prior to in-stalling an LPS. The lightning protection efficiency of the ESE air terminal is insignificantly affected by its time of ad-vance of the upward leader and, more importantly, is similar to that found for the passive air terminal. Therefore also, the estimated risk of loss of cultural heritage does not differ between the passive and ESE air terminals. A new LPS de-sign for the Zalongo monument is required, based on IEC 62305, to enhance the safety of visitors and the preservation of its cultural heritage.