Sideflash 2 : An electrical spark, caused by differences of potential, that occurs between conductive metal bodies or between conductive metal bodies and a component of a lightning protection system or ground
NFPA 780 Standard for the Installation of Lightning Protection Systems, 2008 ed. http://www.uscg.mil/Petaluma/TPF/ET_SMS/Manuals/NF PA_780.pdf, (Std: Instll of Lightning Prot Sys - Amer) {347 NFC}