DIN 25493:2025-03

The purpose of this document is to prevent material damage to component surfaces (for example, corrosive cracking) or malfunctions caused by such damage. This document specifies requirements for assembly aids, seals, gaskets, packaging materials, and thermal insulation materials that come into contact with the surfaces of components in nuclear facilities for which surface cleanliness in accordance with DIN 25410 is required. For these product groups, this document specifies requirements regarding compatibility with the component material and the surrounding media, as well as application instructions. Maximum permissible mass fractions of harmful contaminants are specified. This document has been prepared by Working Committee NA 062-07-55 AA "Hilfssysteme und Betriebsüberwachung in kerntechnischen Anlagen" ("Auxiliary systems and operational monitoring in nuclear facilities") at Technical Section Radiation protection, nuclear technology and fusion technology of DIN Standard Committee Materials Testing (NMP).