Grounding jumpers protect operators and equipment from electrostatic discharge (ESD), directing electric currents to a safe ground. Bonding is the interconnection of metal parts to establish electrical continuity. These definitions are NEC terminology and apply to power system grounding. A. Cable tray may be used as the Equipment Grounding Conductor (EGC) in any installation where qualified persons will service the installed cable tray system. The technical content of IEC publications is kept under constant review by the IEC.