PEM electrolysis and hydrogen purity FAQ
Quick answer
PEM hydrogen purity describes how cleanly a solid-polymer electrolysis cell separates the delivered hydrogen stream, and it is a hardware and manufacturing property rather than a health claim.
- PEM/SPE cells run on pure or distilled water with a solid membrane instead of a caustic liquid electrolyte.
- Carried-over oxygen, water vapour and poor-quality electrode materials are the realistic contaminants.
- Our inhalation systems are independently purity-tested by a third-party laboratory (QTT LH2025050017 and LH2025050018).
Questions and answers
PEM stands for proton exchange membrane, also described as SPE (solid polymer electrolyte). A thin solid membrane sits between two electrodes; when current is applied, water molecules split, protons cross the membrane, and hydrogen forms on one side while oxygen forms on the other. Because the membrane itself is the electrolyte, the cell needs only pure water — no dissolved caustic chemicals.
If you are inhaling a gas, the useful question is what is actually in it. A device that produces an undifferentiated hydrogen-oxygen mixture cannot tell you its hydrogen fraction, and anything carried over from a liquid electrolyte travels with the gas. PEM separation makes the hydrogen stream definable and testable, which is why we publish flow figures for both combined and pure-H₂ modes rather than one headline number.
The two common sources are electrolyte carry-over and materials degradation. Systems using a caustic liquid electrolyte such as potassium hydroxide can entrain traces of it in the gas path, which is why those machines specify electrolyte handling and periodic replacement. Poor-quality cell components and tubing can also shed material over time. A pure-water PEM cell removes the electrolyte source entirely and reduces the maintenance burden.
No, and it is a phrase worth distrusting in this category. “Medical grade” is a regulatory status attached to registered medical devices and to gases supplied under pharmacopoeial standards — not something a consumer wellness appliance carries. Our machines are general wellness devices. What we can substantiate is measured purity, published flow rates, and hardware certification, so we describe those instead.
Independently, by a third-party laboratory rather than by us. The QTT purity reports LH2025050017 and LH2025050018 cover our hydrogen output, and the certificates are published on the site so you can read the actual documents rather than take a marketing figure on trust. Verification of gas purity is an engineering result and says nothing about medical or therapeutic status.
The cell chemistry is the same; scale, delivery and purpose are not. Industrial PEM plant is built for continuous high-volume output feeding a process — fuel cells, gas supply, or injection into combustion equipment — with the hydrogen usually pressurised or piped. Consumer wellness units produce modest flows on demand at ambient pressure for a single session, with no storage. Nothing on this site is an industrial system, and industrial hydrogen equipment is not a wellness product.
No — they are independent specifications. Flow is how much gas per minute; purity is what fraction of it is hydrogen. A high-flow mixed-gas machine can deliver a large volume of a gas whose hydrogen content is undefined. Always read the two numbers separately, and check whether a quoted flow is combined H₂+O₂ or pure H₂.
Our hardware carries CE, FCC and RoHS marks, and manufacturing operates under ISO quality systems. These certifications describe electrical safety, emissions, materials restrictions and manufacturing process — they are hardware and production standards, not medical or therapeutic approvals, and we never present them as such.
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General wellness disclaimer: Hydrogen Machines products are general wellness devices. They are not medical devices and are not intended to diagnose, treat, cure or prevent any disease. Certification and engineering claims describe hardware and manufacturing quality, not medical or therapeutic status. Consult a qualified health professional before starting any new wellness routine.