IEC 60626-1:2009 contains the definitions related to and the general requirements to be fulfilled by combined flexible materials for electrical insulation. This standard does not include mica paper, as primary component, covered by IEC 60371, but mica paper may be used as complementary material. The main changes from the previous edition are that the Scope was revised specifying treatment of mica paper, and Table 1 was revised cancelling materials no longer in use and introducing newer materials.