General (ncpt) GB.1 General This NNA is only applicable to all new overhead lines above A.C. 1kV. This Euronorm is only applicable to new overhead lines and shall not be applied to maintenance@ reconductoring@ tee-offs@ extensions or diversions to existing overhead lines unless specifically required by the Project Specification. For details of the application of this standard for overhead lines constructed with covered conductor refer to the Project Specification. For details of the application of this standard to telecommunication systems involving optical fibres either incorporated in or wrapped around earthwires or conductors or suspended from overhead line supports@ reference should be made to the Project Specification.