DIN EN 62305-1:2011-10

The DIN EN 62305 (VDE 0185) standard series is an overall concept for the protection against lightning and comprehensively takes into account: - the hazard (direct and indirect flashes, current and magnetic field of the flash), - types of damage (step and touch voltages, dangerous sparking, fire, explosion, mechanical and chemical effects, overvoltages), - the objects to be protected (buildings, persons, electrical and electronical systems) and - the protection measures (air-termination systems, down-conductor systems, earth-termination systems, equipotential bonding measures, surge protective devices, shielding of internal lines, line routing and shielding). For this reason, the actual protection standards (Part 3 and Part 4) are preceded by two general standards (Part 1 and Part 2): Part 1 provides information about the hazard related to exposure to lightning, the types of loss, the need for lightning protection and possible protection measures. It also provides an overview of the complete standard series for the protection against lightning which explains the procedure and protection principles based on the parts that follow. The annexes contain the lightning current parameters and lightning protection levels, the time function of the lightning current and its simulation for test purposes, and the test parameters for lightning protection components and the determination of surges due to lightning at different installation points. Part 2 applies the risk analysis to firstly determine the need for protection against lightning for structures and then to select the technically and economically optimal protection measures which are described in detail in the actual protection standards. Finally, the remaining risk is determined. The annexes of Part 2 contain the assessment of the number of dangerous events due to flashes N_X, the probability of damage for structures P_X and the losses L_X. The cost-benefit analysis for economic loss is described. Case studies for structures are conducted. Part 3 deals with the protection of structures against physical damage and life hazards due to direct lightning flashes by a lightning protection system (LPS). It consists of the external LPS (air-termination system, down-conductor systems, earth termination system) and internal LPS (lightning equipotential bonding, separation distance). The characteristics of the LPS are determined by its protection level, which is based on the corresponding lightning protection level (LPS). The annexes of Part 3 deal with the positioning of air-termination systems, minimum cross-section of cable screens in order to avoid dangerous sparking and the share of the lightning current flowing in down-conductor systems for assessment of the separation distance. There is additional information for protection against lightning in the case of structures with a risk of explosion and guidelines for the design, construction, maintenance and inspection of lightning protection systems. Part 4 deals with the protection of structures with electrical and electronic systems against the effects of the lightning electromagnetic impulse (LEMP) by surge protective measures (SPM). They include an individual combination of the following protection measures: earthing and bonding, shielding of internal lines, routing and shielding of lines, coordinated SPD system (SPD = surge protective device). The characteristics of the protective measures shall correspond to the selected lightning protection level (LPL). The basis for the construction of the SPM is the lightning protection zone concept. The annexes of Part 4 provide the basis of electromagnetic environment evaluation in a lightning protection zone. There is additional information on surge protective measures in existing structures and the coordination of surge protective devices as well as the rules for installation of a coordinated SPD system. The responsible Committee is K 251 "Blitzschutzanlagen und Blitzschutzbauteile" ("Lightning protection systems and lightning protection components") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.