GB/Z 30556.8-2025 Active

The purpose of this document is to provide guidance on how to protect distributed infrastructure (power, communications, transportation, pipeline networks, etc.) from the threat of high-altitude electromagnetic pulses (HEMPs). To achieve this goal, it is necessary to describe the particularities of the HEMP threats faced by interconnected and distributed electrical and electronic systems. Specifically, the electromagnetic pulse generated by a nuclear explosion at an altitude of 100 km can cover a ground area with a radius of up to 1,100 km. This means that any distributed or interconnected infrastructure, such as power systems or communication systems, may simultaneously observe disturbances over a wide area. Typically, this situation is not considered in the electromagnetic compatibility (EMC) and electromagnetic protection of individual devices in distributed networks, as local disturbances are generally evaluated in local areas.
This document provides information on the disturbance levels and protection methods for all types of distributed infrastructure. Due to the importance of distributed power systems (substations, power plants, control centers) to other infrastructure, the protection of power systems is described in detail. Communication systems are also very important to most other infrastructure, and the protection of communication networks against HEMPs and other electromagnetic threats has been described in detail in ITU-T.