This Recommendation specifies calculation methods for dangerous effects, tolerance limits of dangerous effects, tolerance limits of electromagnetic effects from a high-voltage substation, distance requirement and protection methods, protective measures, as well as requirements for power frequency magnetic field immunity of servers when an Internet data centre (IDC) is co-sited with a high-voltage substation.

This Recommendation discusses co-sites for an IDC and a high-voltage substation while taking into account proximity, the co-earthing network, and shared accommodation.

This Recommendation is applicable to IDCs and large communication centres co-sited with highvoltage substations. It is possible that this Recommendation may not apply to small Internet data sites.