full list 16.11.2017:

IEC 60099-4:2014 Surge arresters - Part 4: Metal-oxide surge arresters without gaps for a.c. systems
IEC 60099-5:2013 Surge arresters - Part 5: Selection and application recommendations
IEC 60099-6:2002 Surge arresters - Part 6: Surge arresters containing both series and parallel gapped structures - Rated 52 kV and less
IEC PAS 60099-7:2004 Surge arresters - Part 7: Glossary of terms and definitions from IEC publications 60099-1* 60099-4* 60099-6* 61643-1* 61643-12* 61643-21* 61643-311* 61643-321* 61643-331 and 61643-341
IEC 60099-8:2017 Surge arresters - Part 8: Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV
IEC 60099-8:2017 RLV Surge arresters - Part 8: Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV
IEC 60099-9:2014 Surge arresters - Part 9: Metal-oxide surge arresters without gaps for HVDC converter stations


the missing are:

IEC 60099-8:2017 Surge arresters - Part 8: Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV
IEC 60099-8:2017 RLV Surge arresters - Part 8: Metal-oxide surge arresters with external series gap (EGLA) for overhead transmission and distribution lines of a.c. systems above 1 kV


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