DIN EN 62305-2 Beiblatt 1:2013-02

In DIN EN 62305-2 (VDE 0185-305-2), Annex A specifies the assessment of the annual number N of dangerous events dependent on thunderstorm activity in the area where an object to be protected is located. The lightning threat in a particular area is described by means of the ground flash density as the number of flashes per km2 and year. In order to calculate the annual number, a value for the ground flash density is required, which is obtained from cartographical illustrations which are not part of the standard. Isokeraunic level maps providing the number of days of thunderstorms per year were used in the past. The ground flash density can be estimated in accordance with DIN EN 62305-2 (VDE 0185-305-2), Annex A. Nowadays precise measurement data from lightning detection systems is available provided by EUCLID (European Cooperation for Lightning Detection - www.euclid.org) for Europe and BLIDS (Lightning Information Service by Siemens - www.blids.de) for Germany. This Supplement provides a colour assignment to value ranges of ground flash density in a cartographical illustration for number plate areas in Germany. This new edition of the Supplement is an update of the first version in 2007; new statistical evaluations of the measured lightning flashes in Germany are also used. The responsible committee is DKE/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.