BS EN 18191:2026 PDF

1 Scope This document applies to industrial metallic valves for hydrogen use. It contains recommendations and additional requirements applicable to material selection, design, manufacture, and final assessment. This document addresses the following four services/damage mechanisms, which might exist in combinations:

low temperature applications; hydrogen environmental embrittlement (HEE) or hydrogen-induced cracking (HIC); high temperature hydrogen attack (HTHA); hydrogen service with cyclic loads (fatigue).

This document considers the difference between gaseous hydrogen (GH2) and liquid hydrogen (LH2), where necessary. The additional provisions set out in this document do not cover corrosion such as electro-chemical corrosion of metals under participation of hydrogen (e.g. sour gas). This document is based on the requirements contained in the standards specified below:

applications with a maximum allowable pressure PS greater than 0,5 bar in accordance with the European legislation for pressure e...