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

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§5493. Handling of Liquefied Hydrogen Inside Buildings Other Than Separate Buildings and Special Rooms.

(a) Portable liquefied hydrogen containers of 50 gallons or less capacity as permitted in Table H-3 and in compliance with Section 5491(f) when housed inside buildings not located in a special room and exposed to other occupancies shall comply with the following minimum requirements:

(1) Be located 20 feet from flammable liquids and readily combustible materials such as excelsior or paper.

(2) Be located 25 feet from ordinary electrical equipment, and other sources of ignition including process or analytical equipment. (See Section 5489.)

(3) Be located 25 feet from concentrations of people.

(4) Be located 50 feet from intakes of ventilation and air-conditioning equipment or intakes of compressors.

(5) Be located 50 feet from storage of other flammable gases or storage of oxidizing gases.

(6) Containers shall be protected against damage or injury due to falling objects or work activity in the area.

(7) Containers shall be firmly secured and stored in an upright position.

(8) Welding or cutting operations, and smoking shall be prohibited while hydrogen is in the room.

(9) The area shall be adequately ventilated. Safety relief devices on the containers shall be vented directly outdoors or to a suitable hood. See Sections 5469(b) and 5491(f).

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