This NNA determines the requirements which shall be fulfilled while designing and constructing of new overhead lines with nominal system voltages exceeding 1 kV AC. The scope of use of this NNA for temporary lines shall be determined by the Project Specification. For modernisations, reconstructions and refurbishments of the existing lines, the scope and the requirement to comply with PN‑EN‑50341‑1, together with this NNA, shall be determined by the Project Specification.