scope:

This combined NNA is only applicable to all new overhead lines equipped with bare conductors above A.C. 1kV. For what concerns structural aspects this standard applies also to D.C. overhead lines.

This standard specifies the general safety requirements, clarifies the actions that shall be carried out in the project and their relevant combinations, defines characteristics of materials, products and any other aspect relevant to safety of electrical overhead lines as reported in following clause 2. With reference to structural safety aspects, in absence of specific indications, and as an integration to this standard, the dispositions reported in "Norme tecniche sulle costruzioni" apply (see clause 2.3).

This standard is not applicable to overhead lines already existing before its coming into force and shall not be applied to maintenance or reconductoring; the standard can be applied in case of significant modifications of existing lines.

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 Specifications.