Revision of lightning protection map for overhead contact line system

Lightning protection equipment for overhead contact line system is installed by a lightning protection map based on IKL (isokeraunic level). The IKL was created by data observed over 50 years ago, so we are planning to revise the lightning protection map. A new lightning protection map is created by data observed from 2002 to 2011. Number of lightning damage is analyzed, and the validity of the new lightning protection map is discussed.