Key takeaways
- PEM machines deliver ≥99.991% H₂.
- Residual fraction is water vapour, not contaminant.
- Purity is measured at the outlet, not inside the stack.
What "high purity" actually means
Purity is reported as the H₂ fraction in the gas stream leaving the user outlet. PEM separation keeps oxygen below 10 ppm.
Frequently asked questions
No. It's predominantly water vapour from the humidifier.
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Cooling systems
Continue →Purity, tablets & bathing
- Hydrogen Bathing vs Hydrogen Tablets — Saturation versus dilution, compared in full.
- Hydrogen Water Purity — 99.991% certified purity from SPE/PEM electrolysis.
- Hydrogen Tablets: What You Should Know — What dissolving reactive material can leave behind.
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