UL Subject 2264 Water Electrolysis Type Hydrogen Generators

1.1 This Outline covers safety requirements for hydrogen generators that electrolyze water to produce hydrogen. The generators covered by the scope of this Outline use an ion transport medium that consists of one of the following:

1. Aqueous base solutions;
2. Aqueous acid solutions;
3. Solid polymeric materials with acidic function group additions, such as acid proton exchange membrane (PEM); or
4. Solid polymeric materials with basic function group additions, such as anion exchange membrane (AEM).

1.2 The hydrogen generators shall be installed in accordance with NFPA 70, National Electrical Code, and NFPA 2, Hydrogen Code.

1.3 Hydrogen generators that can also be used to generate electricity, such as reversible fuel cells, are excluded from the scope of this Outline.

1.4 Residential hydrogen generators that also supply oxygen as a product are excluded from the scope of this Outline.

1.5 This Outline does not cover hydrogen generators intended for installation in classified locations.