The ramp-up of the hydrogen economy is progressing rapidly across Europe. Electrolysis plants, storage solutions, and hydrogen filling stations are currently being established in industry, energy supply, and logistics.
What is often underestimated:
Hydrogen poses significantly higher requirements for explosion protection than conventional fuels such as methane or propane.
A recent technical article from Chemie Technik clearly shows why existing safety concepts cannot simply be transferred.
Why hydrogen is particularly critical from an explosion protection perspective
Hydrogen has properties that make it one of the most demanding process gases from an explosion protection standpoint:
Explosion range:approximately 4 to 75 vol.-%
extremely low minimum ignition energy
very high flame speed
barely visible flame
very small molecule size → high leakage probability
Even the smallest leaks can lead to the formation of explosive atmospheres. Areas that are still considered non-critical for natural gas can quickly become ATEX zones for hydrogen.
The basic ATEX principle remains – requirements are increasing
The fundamental ATEX systematics remain in place but must be implemented more consistently.
Primary explosion protection
Avoidance of release:
high-quality sealing systems
gas-tight connections
continuous gas monitoring
tested fittings
Secondary explosion protection
Avoidance of effective ignition sources:
suitable ATEX equipment selection
consistentpotential equalization
electrostatic discharge
controlled surface temperatures
Mobile devices or lighting systems are often misjudged here.
Tertiary explosion protection
Limiting the effects:
explosion pressure relief
constructive explosion protection
flame barriers
safe plant layouts
Typical planning errors in hydrogen projects
Current practice shows a recurring pattern:
ATEX devices are used without assessment for hydrogen
Temperature classes are misinterpreted
Grounding and discharge concepts are missing
Ventilation is overrated
mobile devices are selected based on gas group rather than actual risk
Hydrogen diffuses significantly faster than other gases and tends to accumulate in upper areas of installations or closed structures.
As a result, zones often form where they were not originally expected.
Hydrogen changes the ATEX practice
Explosion protection becomes more of aplanning issuerather than an after-the-fact equipment selection.
Already in the early project phases, the following must be considered:
Gas groupIIC
suitableignition protection types
sensors and monitoring
maintenance and service access
Conclusion
Hydrogen does not fundamentally change explosion protection — but it makes it significantly more challenging.
Companies that transfer existing natural gas or chemical plant concepts unchanged significantly increase the risk. A timely assessment of the actual zone formation and the operating resources used is crucial.
The complete technical article is available here: