ABSTRACT: GR-1 replaces TR-EOP-000001, Issue 1, June 1984 and Issue 2, June 1987, but contains NO TECHNICAL CHANGES from that original document. It has been issued strictly to conform with the new Telcordia Technologies document format and GR process, and carries a new issue number and date.

GR-1 provides a description of externally caused voltages and currents that may be encountered at the Local Exchange Carriers (LEC's) Network Interface (NI). The document covers externally caused voltages and currents at the NI as a result of disturbances to the LEC communications network facilities from power systems, lightning, and radio transmitters. Although the effects of disturbances from power systems and lightning may be reduced by electrical protection devices in the network, Customer Premises Equipment (CPE) may still be subjected to voltages or currents of significant magnitudes.

TR-EOP-000001 replaced PUB-43601.