Overview
EN 18191:2026 - Industrial valves: Additional requirements for metallic valves for hydrogen application is an essential European standard developed by CEN. It establishes comprehensive guidelines and recommendations for industrial metallic valves intended for use in hydrogen applications. The document addresses specific hydrogen-related risks by providing additional requirements for material selection, design, manufacturing processes, and the final assessment of valves utilized in hydrogen environments.
This standard is particularly relevant as hydrogen technologies expand across industries such as energy, chemical processing, storage, transportation, and distribution. EN 18191:2026 supports the safe and reliable integration of metallic valves in systems handling both gaseous hydrogen (GH2) and liquid hydrogen (LH2), ensuring compliance with stringent safety regulations and proven engineering practices.
Key Topics
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Material Selection: Guidance for choosing materials resistant to hydrogen-specific damage, including embrittlement, high temperature hydrogen attack, and suitability under cyclic loads. Special attention is given to susceptibility of steels, stainless steels, cast irons, copper alloys, aluminium alloys, nickel, titanium, and zirconium in hydrogen applications.
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Design Considerations: Criteria for stress assessment, temperature ranges, and accommodation for hydrogen partial pressures in valves. Emphasis is placed on robust sealing, minimization of stress concentrators, and design provisions tailored to hydrogen’s unique properties.
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Manufacturing and Assembly: Requirements for welding (including consumables), cold forming, strain hardening, and quality control measures. Sound manufacturing practice is mandated to mitigate porosity, leakage risks, and to maintain structural integrity.
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Testing and Final Assessment: Testing protocols for tightness, shell and seat integrity, and specific tests for low temperature hydrogen service. The standard outlines inspection documentation and marking requirements to certify compliance.
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Damage Mechanisms Addressed:
- Low temperature applications (including cryogenic hydrogen)
- Hydrogen environmental embrittlement (HEE) / hydrogen-induced cracking (HIC)
- High temperature hydrogen attack (HTHA)
- Cyclic load fatigue in hydrogen service
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GH2 vs. LH2: Differentiates requirements where necessary, recognizing the distinct handling and operational challenges each hydrogen state presents.
Applications
EN 18191:2026 applies to the full lifecycle of metallic industrial valves used in hydrogen service, including:
- Hydrogen production plants: Valves in electrolyzers, reformers, and compression systems.
- Processing and storage: Cryogenic storage tanks, high-pressure vessels, and related piping networks.
- Transport and distribution: Hydrogen pipelines, fueling stations, and gas distribution networks.
- End-use sectors: Industrial applications, laboratories, chemical processing plants, and energy systems (including hydrogen fuel cells and renewable energy integration).
Adherence to this standard enables organizations to:
- Enhance safety and reliability in hydrogen systems.
- Prolong service life and reduce maintenance costs of valves.
- Demonstrate compliance with European safety directives and emerging hydrogen legislation.
- Facilitate interoperability and trade in the growing hydrogen value chain.
Related Standards
EN 18191:2026 is complemented by several other European standards to ensure comprehensive valve performance and safety:
- EN 16668: Requirements and testing for metallic valves as pressure accessories
- EN 12569: Chemical and petrochemical valve applications
- EN 13774: Gas distribution system valves
- EN 14141: Gas transportation system valves
- EN 12516 series: Valve design, materials, and component requirements
- EN 12266 series: Testing procedures for industrial valves
- EN 10213: Steel castings for pressure purposes
- EN ISO 28921: Isolating valves for low-temperature applications
These standards collectively establish a harmonized framework for the safe deployment of metallic industrial valves in hydrogen environments.
By following EN 18191:2026, industries adopting hydrogen technologies can optimize valve selection and system design, achieving superior safety, performance, and regulatory compliance across the hydrogen supply chain.