According to this formula, for risk evaluation, knowledge of the three elements of the product NPL, i.e. the number N of strikes influencing the structure, the probability P of damage due to one lightning strike and the amount L of relative loss, must be known.
The entire expected risk may be composed of several components depending on the lightning strike location, the features of the structure and its equipment, the type of damage or a group of damages, and the type of loss. Therefore, it is possible to evalu- ate one component, a selected group of components and the whole combination.