scope:

PURPOSE AND SCOPE

Oil leaks have historically been a problem for oil-filled cables: as oil is a pollutant it is important to minimise the amount lost to the environment. National Grid is committed to the prevention of pollution and continual improvement of environmental performance and will undertake measures, where necessary, to improve the efficiency of leak location and to try to contain any lost oil. At present there are no industry-wide standards to define what measures should be adopted.

To help reduce the impact of oil leaks National Grid continues to support a range of initiatives such as:

(a) The use of Dralim, a transducer based oil pressure monitoring system

(b) The use of Perfluorocarbon Tracing (PFT) to detect leaks without the need to dig

This Technical Guidance Note (TGN) describes suitable installation techniques of systems to detect and contain leaking oil from power cables.