Telecommunications central offices, data centers, electronic equipment enclosures (EEE), and similar type facilities are often subjected to disturbances from lightning and ac power link faults, either directly or indirectly, through the communications cables and ac power facilities that serve them. This standard provides the minimum electrical protection, grounding, and bonding criteria necessary to mitigate the disruptive and damaging effects of lightning and ac power faults. It is intended to serve as a guide for designers of such facilities in the application of electrical protection, grounding, and bonding as a function of the electrical environment.