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

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§5496. Special Rooms.

(a) Floors, walls and ceilings 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 doors shall be located in such a manner that they will be accessible in an emergency. Windows shall be of shatterproof glass or plastic in metal frames.

(b) Ventilation shall be as provided in Section 5495(b).

(c) Explosion venting shall be provided in exterior walls or roof only. The venting area shall be equal to not less than one square foot per 30 cubic feet of room volume and may consist of any one or any combination of the following: walls of light noncombustible material; lightly fastened hatch covers; lightly fastened swinging doors opening outward in exterior walls; lightly fastened walls or roofs designed to relieve at a maximum pressure of 25 pounds per square foot.

(d) There shall be no sources of ignition.

(e) Electrical wiring and equipment shall comply with Section 5489 except that the provisions of Subsection (b) of Section 5489 shall apply to all electrical wiring and equipment in the special room.

(f) Heating, if provided, shall be steam, hot water, or by other indirect means. (Title 24, T8-5496)


1. Amendment of subsection (e) 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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