This part of IEC 60641 applies to pressboard and presspaper for electrical purposes. The series does not apply to laminated material. It specifies the test methods to be used in testing pressboard and presspaper for electrical purposes to meet the requirements prescribed in the specification sheets of Part 3. In this standard, reference is made in several places to ISO standards accompanied by a short description of the method used. It is to be understood that this short description is meant for identification purposes only and that all details should be taken from the ISO standard itself.