IEC 60099-4:2004+A1:2006+A2:2009 Applies to non-linear metal-oxide resistor type surge arresters without spark gaps designed to limit voltage surges on a.c. power circuits. This consolidated version consists of the second edition (2004), its amendment 1 (2006) and its amendment 2 (2009). Therefore, no need to order amendments in addition to this publication.