Hydrogen gas safety fundamentals.
Molecular hydrogen (H₂) is non-toxic. It is produced naturally in the human gut by intestinal bacteria fermenting fibre — every adult exhales small amounts of hydrogen every day. The US FDA has classified hydrogen as Generally Recognised As Safe (GRAS) for food applications. None of this is a treatment claim — it is a baseline safety profile.
At what concentrations is hydrogen safe to inhale?
Published research on hydrogen inhalation typically uses concentrations of 1–4% H₂ in air. The lower flammability threshold for hydrogen in open air is 4%. Consumer PEM inhalers deliver hydrogen at flow rates that, when mixed with normal room air during breathing, stay well below this threshold. The machine produces hydrogen on demand and does not store it under pressure.
What makes a machine safe.
- PEM electrolysis with gas separation — H₂ and O₂ are kept in separate chambers and exit through separate outlets. No mixed-gas storage.
- No pressurised reservoir — gas is consumed as it is produced.
- Automatic shutoff — over-temperature, over-pressure, and low-water cut-offs.
- Certified components — independently tested for emissions and restricted substances.
Certifications that indicate safety compliance.
- FCC Part 15 Subpart B — electromagnetic emissions. Confirms the unit will not interfere with other electronics.
- CE — European safety conformity for electrical equipment.
- RoHS — restriction of hazardous substances in electronics.
- ISO 13485 — manufacturing quality-management system used in regulated production environments.
Safe operating guidelines.
- Distilled water only — never tap, filtered or mineral water.
- Operate in a well-ventilated room, not an enclosed cupboard.
- Keep away from open flame or sparks during operation.
- Follow the manufacturer's flow-rate and session-length guidelines.
- Replace cannulas every 2–4 weeks with daily use.
What to avoid.
- Uncertified machines with no published FCC, CE or RoHS documentation.
- Machines without internal H₂/O₂ gas separation.
- Any unit that stores mixed H₂+O₂ gas under pressure (this is not how a properly engineered PEM inhaler works).
- Alkaline-electrolyte machines marketed for home use — these use corrosive chemicals and produce mixed gas streams.
Our certification documentation.
Every machine we sell carries the full certification stack. See the certifications page for the downloadable FCC test report, CE declaration and ISO 13485 manufacturing certificate. For more on what to check before any purchase, see what to look for in a hydrogen inhaler and the safety page.