Specifically Externally Gapped Line Arresters (EGLA) defined in IEC 60099-8 . 2. Key Updates in the Latest Edition (Edition 3.0)

The IEC 60099-5 standard provides non-mandatory but highly recommended guidelines for the selection of surge arresters in three-phase systems with nominal voltages . It covers several specific arrester technologies: Gapless Metal-Oxide (MO) Arresters: Defined in IEC 60099-4 .

The standard, titled "Surge arresters – Part 5: Selection and application recommendations," is the definitive global guide for engineers designing and maintaining high-voltage power systems. As of early 2026, the current active version is IEC 60099-5:2018 (Edition 3.0) .

Annex D was updated to include modern service monitoring techniques, such as leakage current measurement with harmonic compensation.