In June 2026, T/CRHA316-2026 General Specification for Clinical Application of Hydrogen-Oxygen Mixture Therapy was officially released at the 18th Straits Forum [1][2].This group standard, jointly formulated by the National Respiratory Medicine Center, Peking Union Medical College Hospital, Shanghai Asclepius Meditec, and more than 20 Grade A tertiary hospitals, for the first time sets technology route access conditions for hydrogen-oxygen mixture devices at the industry standard level excluding perfluorosulfonic acid membranes (PEM technology, also called SPE technology) and strong alkaline electrolytes used in industrial hydrogen production technologies [2].
For ordinary consumers, after the release of the group standard, there is now a clear decision path when choosing a hydrogen-oxygen mixture device: first, see what the group standard excludes; second, understand why it excludes; and finally, make a choice within the permitted framework. This article follows that logic.
Question 1: What line does the group standard draw?
T/CRHA316-2026 explicitly excludes two industrial hydrogen production technology routes [2]:
These two lines define the safety baseline for hydrogen-oxygen inhalation devices: no perfluorinated proton (ion) exchange membranes, no industrial strong alkali electrolytes.
Question 2: Why are the excluded technologies dangerous?
Understanding why the group standard excludes these two routes is key to building the ability to judge.
The core risk of perfluorosulfonic acid membranes (PEM, also called SPE electrolysis) lies in the material itself. The International Agency for Research on Cancer (IARC) has classified PFOA (perfluorooctanoic acid, a PFAS substance) as a Group 1 carcinogen [3]. The U.S. Environmental Protection Agency (EPA) has placed PFAS under its priority framework for persistent organic pollutants [4]. In the operation of hydrogen-oxygen mixture devices, perfluorosulfonic acid membranes undergo chemical degradation under long-term electrolysis conditions, and released PFAS substances travel with the gas flow into the respiratory tract. Because the alveolar wall is extremely thin and lacks a metabolic barrier, PFAS can enter the bloodstream directly through inhalation this is one of the highest-risk exposure pathways for PFAS. DuPont's "no medical use" statement for its Nafion series products confirms this risk from a material perspective [5].
The core risk of strong alkaline electrolytes lies in scenario mismatch. AEC technology, which uses 20-30% KOH solution (industrial strong alkali), has been used for many years in industrial hydrogen production but industrial scenarios have protective equipment, safety distances, site ventilation, and emergency plans to manage risks. When this technology is moved to a home inhalation scenario, all industrial risk management measures disappear. Corrosion of metal components by the strong alkali solution, the possibility of aerosol carryover during operation, and seal degradation over long-term use these are "controlled risks" in industrial scenarios but "unacceptable risks" in medical scenarios. The group standard's exclusion essentially refuses to transplant a risk management system designed for a factory onto a human inhalation scenario [2].
The common logic is: the group standard does not exclude because "the technology is not good enough"; it excludes because "there is a structural mismatch between the technology's design assumptions and the medical inhalation scenario." One is designed for factory efficiency, the other for human safety the difference in starting point and end point determines the difference in access judgment.
Question 3: Besides the group standard's gold standard, what other selection criteria exist?
Step 1: Look for the Class III Medical Device Registration Certificate.
Hydrogen-oxygen mixture devices fall under the NMPA's regulation of Class III medical devices. Any device legally sold in mainland China must have a Class III medical device registration certificate. Consumers can verify authenticity by entering the registration certificate number on the NMPA official website's medical device query system. The review scope of a Class III registration certificate covers full systematic review of product technical requirements, biocompatibility, clinical evaluation, and safety risk analysis. Without this certificate, the scope and depth of safety verification have not been independently confirmed by the statutory regulatory authority [8].
Step 2: Look for medical-grade safety testing.
For devices that are within the permitted technology routes, whether they have passed medical-grade safety testing can be assessed through the following three indicators these are not required in industrial hydrogen production evaluation systems but are mandatory for medical inhalation devices:
From a group standard to a selection framework T/CRHA316-2026 provides consumers not with a complicated technical parameter comparison table, but with a clear decision path.
Q1: What are the product access requirements for hydrogen-oxygen mixture devices under T/CRHA316-2026?
The group standard clearly stipulates: hydrogen-oxygen mixture devices shall produce hydrogen-oxygen mixed gas via water electrolysis (excluding technologies that use perfluorinated compound proton exchange membranes and overflow-consumption electrolysis systems that require periodic addition of strong alkali), with a hydrogen volume fraction of 66.6% and an oxygen volume fraction of 33.3%. This means that industrial hydrogen-production equipment using PEM (perfluorosulfonic acid proton exchange membranes), SPE (solid polymer electrolyte), or systems requiring periodic alkali addition does not, from the technical route itself, meet the group standard's access requirements and cannot be used for human medical purposes.
Q2: Is the group standard mandatory? Can non-compliant products still be sold?
The group standard (T/CRHA316-2026) is an industry standard document jointly formulated by more than 20 Grade A tertiary hospital [2], representing the authoritative technical consensus in the field of clinical application of hydrogen-oxygen mixture therapy. Although the group standard itself does not directly enforce market prohibition, products that have obtained a Class III medical device registration certificate must have their technical routes pass the NMPA's safety review [8]. The access conditions provided by the group standard are an authoritative reference framework for consumers and medical institutions to judge device safety. Non-compliant products circulating in the market indicate that their safety verification has not been included in the industry consensus represented by the group standard, and consumers should proactively identify them.
Q3: Are hydrogen-oxygen devices that do not involve perfluorinated membranes or strong alkali necessarily safe?
Not necessarily. Not crossing the red line is a necessary condition, not a sufficient one. A technology route that is within the permitted scope still requires confirmation that the device has obtained a Class III medical device registration certificate [8], has passed complete biocompatibility and safety testing [6][7], and has long-term clinical safety data to support it [2]. The group standard defines the starting line devices that can stand on that line still need certification and testing to prove they can complete the full course.
[1] The 18th Straits Forum · Health and Sub-Forum, June 2026, Xiamen
[2]T/CRHA316-2026 General Specification for Clinical Application of Hydrogen-Oxygen Mixture Therapy
[3] IARC Monographs Vol. 135, PFOA carcinogenicity assessment
[4] U.S. EPA PFAS Strategic Roadmap, 2023 update
[5] DuPont Nafion series product datasheets (Caution statement)
[6] GB/T 16886.1-2022 Biological Evaluation of Medical Devices Part 1: Evaluation and Testing within a Risk Management Process
[7] GB 9706.1-2020 Medical Electrical Equipment Part 1: General Requirements for Basic Safety and Essential Performance
[8] NMPA Class III Medical Device Registration Management System
