A risk analysis allows to assess the risk potential for structures and to take specific measures to reduce the risks. Thus, economically feasible protection measures can be selected that are adapted to the properties and use of the building. A risk analysis does not only allow to determine the class of LPS, but also to develop a complete protection concept including the required LEMP (Lightning Electromagnetic Pulses) protection measures
The above diagram is a demonstration on the Rolling Sphere method. A sphere of radius equal to the striking distant is usually employed to visualize the likely stroke termination point, the so-called Rolling Sphere Method (RSM). Application of RSM involves rolling an imaginary sphere of prescribed radius over the air termination network. The sphere rolls up and over (and is supported by) air terminal, shield wires, and other grounded metal objects intended for direct lightning protection. A piece of equipment is protected from a direct stroke if it remains below a curved surface of the sphere by virtue of the sphere’s being elevated by air terminals or other devices. Equipment that touches the sphere or penetrates its surface is not protected.