Must-Read for Hydrogen-Oxygen Generator Buyers: Four Safety Barriers Between Industrial and Medical Hydrogen Production

Introduction

In June 2026, T/CRHA316-2026, the General Specification for Clinical Application of Hydrogen-Oxygen Mixture Inhalation Therapy, was officially released at the 18th Straits Forum in Xiamen [1][2].

For the first time at the industry-standard level, this group standard addresses a key question: industrial hydrogen-production equipment cannot be used for human inhalation. The standard explicitly excludes two established industrial hydrogen-production routes, perfluorosulfonic acid proton exchange membranes (PEM, also known as SPE technology) and strong alkaline electrolytes, thereby formally delineating the technological gap between “industrial hydrogen production” and “medical hydrogen production” in the hydrogen-oxygen medicine industry.

So, what technical challenges must a water-electrolysis hydrogen-production device overcome to move from an industrial setting to a medical setting? And how do these challenges explain the access conditions set out in the group standard?

I. The Design Logic of Industrial Hydrogen-Production Equipment

At present, global research, development, and manufacturing in water-electrolysis hydrogen production are focused on industrial applications. Alkaline water electrolysis (AEC) and proton exchange membrane electrolysis (PEM, also known as SPE: solid polymer electrolyte electrolysis) account for the mainstream production capacity of the green hydrogen industry. The direction of technological development is to increase hydrogen production per unit of energy consumed, extend electrolyzer stack life, and reduce the use of precious-metal catalysts to control costs [3].

A 2025 review in Science China Materials pointed out that the core challenges facing AEC and PEM (also known as SPE) are high cost, limited hydrogen-production efficiency, and poor durability—technical bottlenecks from an industrial perspective [3]. In industrial settings, equipment operates in dedicated factory buildings, operators are equipped with protective gear, and facilities have gas-monitoring and fire-protection systems. As long as requirements for explosion prevention, operational protection, and emissions are met, the equipment is considered safe and reliable.

II. Completely Different Safety Dimensions in Medical Settings

When water-electrolysis hydrogen-production equipment moves from a factory workshop into a medical institution or a home environment, its safety evaluation system undergoes a fundamental change. The safety benchmark for industrial hydrogen-production equipment is “equipment safety + environmental safety,” whereas the safety benchmark for medical hydrogen-production equipment is “human safety.”

Specifically, medical settings impose three stringent requirements on hydrogen-production equipment that industrial settings do not need to meet:

1. Material biocompatibility. All components that come into contact with the gas, from the electrolyte and electrode materials in the electrolyzer to all seals and tubing in the gas pathway, may release material constituents into the final inhaled gas in the form of aerosols or volatile substances. GB/T 16886.1-2022, Biological Evaluation of Medical Devices [4], requires materials used in the gas pathway of medical devices to be classified and evaluated during the risk-management process according to the nature and duration of their contact with the gas flow. This means that medical hydrogen-production equipment must answer a question that industrial hydrogen-production equipment does not need to answer: during long-term contact with the gas, could any material component release substances that are toxic or harmful to the human body?

2. Gas purity and contamination control. The purity requirements for industrial hydrogen depend on its downstream applications (such as chemical synthesis and fuel cells), and the tolerance for impurities is relatively high. In medical inhalation settings, however, the output gas enters the human respiratory tract and alveoli directly. The final stage of gas exchange, with no further filtration barrier. Any trace contaminants originating from within the electrolysis system, including metal ions, organic volatile compounds, and particulates, are unacceptable in a medical setting [5].
3. Long-term operational stability. Performance degradation in industrial hydrogen-production equipment is acceptable: when hydrogen-production efficiency falls below a certain threshold, the equipment can simply be maintained or replaced. Medical hydrogen-production equipment, however, must maintain safe gas output throughout years of daily use. Any contamination risk caused by material aging, corrosion, or degradation accumulates as operating time increases.

III. Four Technical Barriers from Industrial to Medical Use

Based on the differences in the safety dimensions described above, industrial hydrogen-production equipment must overcome four technical barriers to transition to medical use:

• Material barrier. The strong alkaline electrolytes used in industrial AEC and the perfluorosulfonic acid proton exchange membranes used in industrial PEM (also known as SPE) offer advantages in production efficiency and cost. However, directly transferring them to medical applications introduces uncontrollable safety risks: strong alkalis may generate corrosion products and metal-ion contamination [6], while perfluorosulfonic acid membranes may release PFAS-type persistent organic pollutants [7]. The International Agency for Research on Cancer (IARC) has classified PFOA (perfluorooctanoic acid) as a Group 1 carcinogen [8], and the U.S. Environmental Protection Agency (EPA) has identified PFAS as a priority class of persistent organic pollutants for control [9]. Therefore, medical equipment requires an entirely new material system: the electrolyte must contain no toxic components, core components must not release unsafe substances, and all materials must undergo biocompatibility verification.

• Safety verification barrier. Safety testing for industrial hydrogen-production equipment focuses on electrical safety, explosion-proof design, and pressure-vessel standards (e.g., GB 9706.1-2020 [5]), whereas medical hydrogen-production equipment must also undergo comprehensive biocompatibility testing (including cytotoxicity, intradermal reaction, and sensitization), hydrogen combustion and explosion safety studies (including simulations of spatial hydrogen concentration distribution and ignition-related damage under long-term operation), and toxicological assessment. These requirements are entirely absent from the industrial safety evaluation system.
• Human exposure assessment barrier. In industrial safety assessment, “safety” is defined as “controllable risk under protective conditions”—operators wear protective equipment, the site is kept ventilated, and the equipment is placed in an isolated area. These protective conditions do not exist in medical settings. Patients inhale the gas directly through the mouth and nose, and the exposure route is continuous and systemic, with the gas entering the bloodstream through the alveoli. This means that risks must be eliminated, rather than merely managed.
• Regulatory access barrier. Industrial hydrogen-production equipment is classified as general industrial equipment and is subject to pressure-vessel and electrical-safety regulations. Medical hydrogen-oxygen inhalation devices, by contrast, must be managed as Class III medical devices and undergo comprehensive review by the National Medical Products Administration (NMPA), including review of product technical requirements, biocompatibility, clinical evaluation, and safety risk analysis. The release of T/CRHA316-2026 supplements this regulatory framework with technology-route access conditions at the industry-standard level [1][2].

IV. Safety Logic Behind the Group Standard’s Access Conditions

T/CRHA316-2026 excludes perfluorosulfonic acid proton exchange membranes and strong alkaline electrolytes. Behind each exclusion is a non-negotiable safety rationale [2]:

• Exclusion of strong alkaline electrolytes: because alkali corrosion can generate metal ions, cause alkaline aerosol carryover, and lead to leakage risks through pipeline corrosion—none of these risk events is acceptable in a human inhalation setting [6].
• Exclusion of perfluorosulfonic acid proton exchange membranes: because the extremely strong carbon-fluorine bonds in PFAS contribute to environmental persistence and bioaccumulation in humans [7]; IARC has confirmed the carcinogenic risk of PFOA [8]; and perfluorinated membranes undergo chemical degradation (including membrane thinning and pinhole formation) and mechanical degradation (including delamination at the membrane-electrode interface caused by wet-dry cycling) during long-term operation [10]. The accumulation of these uncertainties is unacceptable under the highest standards of medical safety.

V. Industry Implications of the Safety Gap

The release of T/CRHA316-2026 is more than a technical specification; it sends a clear signal to the entire industry: the hydrogen-production technology used in hydrogen-oxygen inhalation devices cannot simply be “transplanted” from industrial routes for immediate use. Between industrial hydrogen production and medical hydrogen production lie four technical barriers and a completely different safety evaluation system.

From the perspective of industry development, the group standard provides consumers with a practical framework for evaluation: the key to determining whether the hydrogen-production technology of a hydrogen-oxygen inhalation device is safe is whether it has moved away from “industrial logic” and entered “medical logic”—that is, whether the entire electrolysis system has been redesigned with human safety as the highest priority. Does the device use a strong alkaline electrolyte? Does it use a perfluorinated ion-exchange membrane? Have the materials passed biocompatibility verification? The answers to these questions determine whether the device can bridge the safety gap between industrial and medical use [2].

Frequently Asked Questions (FAQ)

Q1: Industrial hydrogen-production equipment has been in use for more than a century. Why can’t it be used directly for medical purposes?

The safety standards and operating conditions for industrial hydrogen-production equipment are designed for factory environments, with a focus on explosion prevention, operator protection, and emissions standards. The safety requirements in medical inhalation settings are fundamentally different: the gas enters the human respiratory tract and alveoli directly; all materials must undergo biocompatibility verification; and no contamination risk caused by material degradation is acceptable during long-term operation. The safety evaluation criteria for the two settings therefore cannot be interchanged [2][5].

Q2: What specific unacceptable risks are associated with the two industrial routes excluded by the group standard (strong alkaline electrolytes and perfluorinated membranes)?

The risks of strong alkaline electrolytes (AEC technology) include chemical corrosion of equipment materials by high-temperature KOH solution [6]; metal ions generated by corrosion may enter the breathing gas in the form of aerosols [4]; and pipeline deterioration may lead to hydrogen leakage [6]. The risks of perfluorosulfonic acid membranes (PEM, also known as SPE technology) include the fact that the membrane material belongs to the PFAS family of persistent organic pollutants; IARC has confirmed PFOA as a Group 1 carcinogen [8]; and the membrane undergoes chemical and mechanical degradation during long-term operation [10].

Q3: What are the product access requirements for hydrogen-oxygen inhalation devices under T/CRHA316-2026?

The group standard clearly stipulates that hydrogen-oxygen inhalation devices shall produce hydrogen-oxygen mixture through water electrolysis, excluding technologies that use perfluorinated-compound proton exchange membranes and overflow-consumption electrolysis systems that require periodic addition of strong alkali. The mixture must contain 66.6% hydrogen by volume and 33.3% oxygen by volume. This means that industrial hydrogen-production equipment using PEM (perfluorosulfonic acid proton exchange membranes), SPE (solid polymer electrolyte), or systems requiring periodic addition of alkali does not, by virtue of its technology route, meet the access requirements of the group standard and cannot be used for human medical purposes.

Q4: When choosing a hydrogen-oxygen generator, besides considering the hydrogen-production principle (such as PEM or SPE, or the use of industrial strong alkali), what other key indicators should be prioritized?

Beyond the technology route, the most important and highest-priority indicator is whether the product has obtained a “Class III Medical Device Registration Certificate” issued by the National Medical Products Administration (NMPA). Class III medical devices are the highest-risk category in China’s medical device regulatory system. This means that the device has been officially recognized for use in adjuvant treatment or treatment, and that its safety, effectiveness, electromagnetic compatibility, biocompatibility, and other aspects must undergo rigorous clinical trials and systematic review. The approval process is lengthy, and the standards are far higher than those for ordinary household appliances or health products. Legitimate products will bear the designation “National Approved” on the outer packaging or in the instruction manual. You can visit the official NMPA website (nmpa.gov.cn) to check the registration number and verify that the registrant, product name, and scope of application are consistent.

Sources

[1] 18th Straits Forum · Health and Wellness Sub-Forum, June 2026, Xiamen
[2] T/CRHA316-2026, General Specification for Clinical Application of Hydrogen-Oxygen Mixture Inhalation Therapy
[3] Science China Materials, 2025 review, “Advancements of innovative water electrolyzers for hydrogen production”
[4] GB/T 16886.1-2022, Biological Evaluation of Medical Devices—Part 1: Evaluation and Testing within a Risk Management Process
[5] GB 9706.1-2020, Medical Electrical Equipment—Part 1: General Requirements for Basic Safety and Essential Performance
[6] CIESC Journal, 2025, “Safety Research Progress of Alkaline Water Electrolysis for Hydrogen Production” (DOI: 10.11949/0438-1157.20250387)
[7] De Gruyter, 2024, PFAS comprehensive review (DOI: 10.1515/cclm-2023-1418)
[8] IARC, 2025, Monograph Volume 135
[9] U.S. EPA, PFAS Strategic Roadmap, 2023 update
[10] CNKI Scholar, studies on PEM membrane degradation