Safety is non-negotiable in hydrogen systems —With extreme pressures, temperatures, and hydrogen’s unique properties, only validated sealing solutions with ultra-low permeation and proven RGD resistance can guarantee reliability.
Trusted results, ready for scale-up —With complete material traceability, external certifications and local-for-local European manufacturing, Angst+Pfister provides end-to-end support that shortens development cycles and ensures long-term hydrogen safety and compliance.
Angst+Pfister Group
Imagine a hydrogen storage tank operating at 700 bar.
A single leak — barely visible, almost silent — can cause pressure loss, trigger shutdowns, or, in the worst case, ignite. The difference between safety and disaster often comes down to something no bigger than a fingertip: the seal.
Hydrogen is on track to become the sustainable, clean fuel of tomorrow — powering vehicles, stabilizing renewable grids, and decarbonizing hard-to-abate industries. Yet, its promise hinges on something deceptively small: the integrity of the seals that keep hydrogen contained. If safety fails, adoption stalls. Reliable sealing isn’t a footnote. It’s the gatekeeper that determines whether plans move from pilot to production. In hydrogen systems operating from–40 degrees Celsius to +150 degrees C and up to 1000 bar, every microleak leads to energy loss, safety risks and system failure. In addition, the right materials and designs are decisive for progress.
That’s where Angst+Pfister steps in. Our engineered sealing solutions are specifically developed to withstand hydrogen permeation, extreme pressures, temperature cycles and rapid decompression, delivering confidence in the most demanding hydrogen environments.
The Challenge: Hydrogen Pushes Materials to Their Limits
Sealing in hydrogen systems isn’t routine engineering. Hydrogen is the smallest molecule — and the biggest challenge. Its tiny molecular size allows it to slip through pathways that contain other gases with ease, driving higher permeation rates in elastomers and thermoplastics, stricter leakage thresholds, and a drastically reduced margin for error. Combined with hydrogen’s high flammability in air, even a small leak can escalate into ignition, explosions or force a depressurization that halts operations. The consequences span lives, infrastructure and reputations.
Applications such as electrolyzers, fuel cells, compressors and storage tanks must therefore operate safely under extreme conditions:
Pressures up to 1000 bar
Wide temperature swings from –40 degrees Celsius to +150 degrees Celsius
No lubrication for dynamic seals
Extremely low permissible leakage rates
Exposure to 100% hydrogen atmospheres
Risks of rapid gas decompression (RGD) and hydrogen embrittlement
Under these demands, conventional elastomers often fail prematurely — through swelling, shrinkage, embrittlement or microleakage — compromising system integrity, uptime and safety. The result is clear: only materials with very low permeation and proven RGD resistance can make hydrogen applications both reliable and safe.
The Solution: Sealing Materials Built for Hydrogen
Meeting hydrogen’s extreme demands starts at the molecular level. Specialized elastomers such as FKM, EPDM and HNBR, combined with advanced thermoplastics like PTFE and UHMW-PE, are engineered to resist hydrogen diffusion, extrusion and rapid gas decompression (RGD). But materials alone are not enough: Reliability comes from pairing them with application-specific geometries such as O-Rings,PTFE lip seals, spring-energized profiles and back-up rings that ensure tight sealing under pressure, minimize extrusion, and perform across wide temperature ranges.
At Angst+Pfister, every solution is validated in 100% hydrogen environments. Our safety-first testing protocols go far beyond spreadsheets and models, subjecting seals to permeation, leakage, aging, durability and RGD tests under conditions of up to 1000 bar. Dedicated hydrogen laboratories and external certifications provide real-world assurance that conventional designs cannot match.
Resistance to explosive decompression (validated to NORSOK M-710 and ISO 23936-2)
Wide temperature stability for both static and dynamic applications
High extrusion resistance under demanding pressure cycles
Optimized geometries for valve seats, housings, connectors, compressors and fuel cells
By combining engineered materials, tailored designs and rigorous hydrogen-specific testing, we create sealing solutions that don’t just meet safety standards — they redefine them.
We do more than just recommend materials: We deliver verified, application-specific sealing systems that have been tested under realistic H₂ conditions.
The Result: Validated Performance, Trusted Safety and Proven Differentiation
Spreadsheets don’t stop leaks — real-world testing does. Our sealing solutions emerge from hydrogen-specific validation with results you can measure ultra-low permeation, resistance to explosive decompression, and reliable performance under extreme pressures and temperatures. Dedicated in-house hydrogen lab protocols and external certifications turn proof into trust — ensuring safer systems, longer service life, and a clear edge over conventional designs.
Verified test protocols (permeation, leakage, aging, RGD)
Sealing designs optimized via finite element analysis (FEA)
Broad materials portfolio matched to each application’s pressure, temperature, and movement profile
End-to-end support from engineering through logistics
Local-for-local European manufacturing
Before and After: Engineering for Hydrogen Safety
Sealing Performance
Before – Standard Elastomers
After – Angst+Pfister Solutions
Leakage Risk
High, especially at 1000 bar
Minimal, verified in 100% H₂ tests
Permeation Rate
Unpredictable, often above threshold
Significantly reduced
Decompression Resilience
Prone to blistering or cracking
RGD-resistant, tested to ISO/NORSOK
Dynamic Seal Reliability
Frequent wear, especially unlubricated
PTFE + spring designs avoid metal
Certification Coverage
Partial or missing
Tested to ISO 23936-2, DVGW ZP 5101 and others
Application Compatibility
Limited
Fuel cells, compressors, valves, electrolyzers, H₂ storage and more
Angst+Pfister Group
Use Case: Preventing Failures in Hydrogen Storage Bottles
The challenge: A hydrogen storage equipment manufacturer was experiencing early-stage seal damage in high-pressure tanks, operating at up to 1000 bar. Standard seals showed blistering and leakage after just 10,000 cycles.
Our solution: Angst+Pfister designed a sealing system with:
After more than 60,000 test cycles in 100% hydrogen, the system showed zero leakage and no embrittlement — eliminating the need for midlife maintenance.
What Our Experts Say
“Hydrogen sealing isn’t just about chemical resistance. It’s about controlling diffusion, pressure resilience, and safety margins under extreme conditions. We’ve built a verified sealing material portfolio for this purpose.” — Lorena Casasola, Material Engineer, Angst+Pfister
“Customers are really impressed that we’ve tested our elastomers in 100% hydrogen at pressure. That’s the level of validation they need to trust a solution for the hydrogen economy.” — Peter Schäfer, Senior Engineer Leader, Angst+Pfister
Conclusion: Verified Sealing Performance for Hydrogen Safety
Hydrogen may be the future — but only with materials that perform today. Angst+Pfister’s sealing solutions meet the growing demands of hydrogen mobility, storage and infrastructure with a fully tested and verified portfolio of elastomer and thermoplastic materials.
Our sealing technologies are trusted by leading manufacturers across Europe, and we continue to lead in test validation, material science and industry-specific application support. Our hydrogen sealing portfolio ensures safety, reliability and performance — validated in real-world conditions.
Ready to discuss your hydrogen project?Contact our experts to explore tailored sealing solutions.
Frequently Asked Questions (FAQs)
Why is hydrogen more difficult to seal than other gases? Hydrogen’s small molecular size allows it to permeate standard elastomers, while its explosiveness and pressure demands require extremely resilient materials.
Have these materials been tested in real hydrogen? Yes. Angst+Pfister materials are tested in 100% H₂ under pressure (up to 1000 bar), including leakage, aging and RGD testing.
What types of seals are available? We offer O-Rings, custom elastomer profiles, PTFE lip seals, spring-energized seals and backup ring assemblies for high-pressure use.
How do sealing solutions reduce the risk of accidents? By combining validated materials (FKM, EPDM, HNBR, PTFE) with application-specific geometries (PTFE lip, spring-energized, back-ups), seals maintain tightness across temperature and pressure cycles, reducing permeation and leakage
Which industries use your hydrogen seals? Fuel cell vehicles, electrolyzers, gas storage, distribution systems and high-pressure valve manufacturers.
Can I customize seal geometry? Absolutely. Our application engineers can tailor material and design to your specific system and performance needs.
What industries are most affected by hydrogen safety concerns? Fuel cell mobility, electrolysis plants, storage systems, distribution networks, valves and high-pressure compressor manufacturers.
About Angst+Pfister
The Angst+Pfister Group, headquartered in Switzerland, has been a leading innovation development partner for technical components and engineering solutions for over a hundred years, primarily in the areas of elastomer and rubber-metal parts and compounds.
Through local sales and technical organizations, the company serves more than 20,000 customers in over 50 countries per year. By building up a global network of highly selective companies and partners worldwide over the years, Angst+Pfister operates research and development centers as well as production facilities worldwide to serve customers efficiently at the cutting edge of technology.
Angst+Pfister stands for the highest possible degree of responsibility — good corporate governance, compliance with laws and regulations, fair competition, the well-being of employees, and social and environmental responsibility are guiding principles in all areas of its business.
For more information about our global network, innovation and engineering expertise, visit Angst+Pfister Group.
Angst+Pfister Group
Angst+Pfister Group
Angst+Pfister
