scope:

This Technical Guidance Note (TGN) provides guidance on the monitoring, handling, storage, and disposal of clean and contaminated Sulphur Hexafluoride (SF6) gas, in accordance with IEC 60376 and IEC 60480, which is used as an insulator and/or interrupting medium within transmission equipment.

The contents of this document targets people who work on a regular basis with SF6 filled equipment and provides guidance on issues that may be encountered during the normal life cycle of equipment. It also provides personnel with background information, which can be used to gain a better understanding of the events, which could lead to equipment failure.

This document does not deal in depth with the inherent danger from the electrical or pressurised systems associated with SF6 filled equipment, and assumes the reader to be familiar with appropriate company procedures, safety rules and any associated safety instructions published to manage these dangners.

At the time of writing, this document deals with electrical equipment containing only SF6 gas in an unmixed state, although it is likely National Grid will utilise SF6/Nitrogen gas mixtures as an insulating medium within Gas Insulated Lines (GIL's).