California Code of Regulations
Title 8 - Industrial Relations
Division 1 - Department of Industrial Relations
Chapter 4 - Division of Industrial Safety
Subchapter 7 - General Industry Safety Orders
Group 20 - Flammable Liquids, Gases and Vapors
Article 139 - Oxygen
Section 5501 - Location of Bulk Oxygen Systems

(a) Bulk oxygen storage systems shall be located aboveground out of doors, or shall be installed in a building of noncombustible construction, adequately vented, and used for that purpose exclusively. The location selected shall be such that containers and associated equipment shall not be exposed by electric power lines, flammable or combustible liquid lines, or flammable gas lines.

(b) The system shall be located so that it is readily accessible to mobile supply equipment at ground level and to authorized personnel.

(c) Where oxygen is stored as a liquid, noncombustible surfacing shall be provided in an area extending at least 3 feet from points at ground level upon which any leakage of liquid oxygen might fall during operation of the system and filling of a storage container. Such an area under liquid delivery connections of mobile supply equipment shall be at least the full width of the vehicle and at least 8 feet in the transverse direction. For purposes of this Article, asphaltic or bitumastic paving is considered to be combustible. The slope, if any, of such areas shall consider possible flow of spilled liquid oxygen to adjacent combustible material.

NOTE: When locating bulk oxygen systems near aboveground flammable or combustible liquid storage which may be either indoors or outdoors, it is advisable to locate the system on ground higher than the flammable or combustible liquid storage.

(d) Where it is necessary to locate a bulk oxygen system on ground lower than adjacent flammable or combustible liquid storage, suitable means shall be taken (such as by diking, diversion curbs, or grading) with respect to the adjacent flammable or combustible liquid storage to prevent accumulation of liquids under the bulk oxygen system. (Title 24, T8-5501(a), (b))