This part of IEC 60794-4, which is a family specification, covers optical telecommunication cables, commonly with single-mode fibres1 used primarily in overhead power lines applications. The cables can also be used in other overhead utility networks, such as for telephony or TV. The National Electrical Code® (NEC®) is published by the National Fire Protection Association (NFPA) with the revisions on a three-year schedule. The 2020 NEC, which replaces the 2017 NEC, was issued by the NFPA in August, 2019. It is an honour to present you with the latest version, which is another example of how ITU-T is bridging the standardization gap. ixed” into a building construction from the 01 July 2017. The levels of performance of cables (i.