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Subchapter 7. General Industry Safety Orders
Group 20. Flammable Liquids, Gases and Vapors
Article 138. Hydrogen

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§5476. Special Rooms.

(a) Floor, walls, and ceiling shall have a fire-resistance rating of at least two hours. Walls or partitions shall be continuous from floor to ceiling and shall be securely anchored. At least one wall shall be an exterior wall. Openings to other parts of the building shall not be permitted. Windows and doors shall be in exterior walls and shall be located so as to be readily accessible in case of emergency. Windows shall be of glass or plastic in metal frames.

(b) Ventilation shall be as provided in 5475(b).

(c) Explosion venting shall be as provided in 5475(c).

(d) There shall be no sources of ignition from open flames, electrical equipment, or heating equipment.

(e) Electrical equipment shall be in accordance with the California Electrical Safety Orders for Class I, Division 2 locations.

(f) Heating, if provided, shall be by steam, hot water, or indirect means. (Title 24, T8-5476)


1. Amendment of subsection (a) filed 3-2-76; effective thirtieth day thereafter (Register 76, No. 10).

2. Amendment filed 7-16-76; effective thirtieth day thereafter (Register 76, No. 29).

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