Subpart H
This standard applies to the installation of bulk oxygen systems on industrial and institutional consumer premises and excludes supplier-operated oxygen manufacturing or refilling establishments and systems below the capacity limits in 1910.104(b)(1). See Scope in 1910.104(a) for the exact coverage and exclusions.
A bulk oxygen system is defined as equipment (storage containers, regulators, vaporizers, piping, etc.) that has more than 13,000 cubic feet (NTP) of oxygen connected or ready for service, or more than 25,000 cubic feet (NTP) including unconnected reserves on site. See the definition in 1910.104(b)(1).
Bulk oxygen storage systems must be located above ground outdoors or inside a building of noncombustible construction that is adequately vented and used only for that purpose; they also must not be exposed to electric power lines or flammable liquid or gas lines. See Location requirements in 1910.104(b)(2)(i).
The system must be located so it is readily accessible to mobile supply equipment at ground level and to authorized personnel. See Accessibility in 1910.104(b)(2)(ii).
Where oxygen is stored as a liquid, the area under any place liquid oxygen might fall must be surfaced with noncombustible material (asphaltic or bituminous paving is considered combustible and is not acceptable). See Leakage provisions in 1910.104(b)(2)(iii).
You must keep bulk oxygen storage at least 50 feet from combustible structures and at least 25 feet from structures with fire-resistive exterior walls or sprinklered buildings (but not less than one-half the height of the adjacent side wall). See combustible structure distance in 1910.104(b)(3)(ii) and fire-resistive structure distance in 1910.104(b)(3)(iii).
Bulk oxygen storage must be at least 10 feet from any opening in adjacent walls of fire-resistive structures, and spacing must allow maintenance but not be less than 1 foot. See Openings distance in 1910.104(b)(3)(iv).
Required distances vary with tank type and capacity: for above-ground flammable liquids keep 50 feet for 0–1000 gal and 90 feet for 1001+ gal; for below-ground flammable tanks the horizontal distance is 15 feet (0–1000 gal) or 30 feet (1001+ gal) and 50 feet to filling/vent connections. For combustible liquids above ground keep 25 feet (0–1000 gal) or 50 feet (1001+ gal); for below-ground combustible tanks keep 15 feet horizontally and 40 feet to filling/vent openings. See the distance tables in 1910.104(b)(3)(v), 1910.104(b)(3)(vi), 1910.104(b)(3)(vii), and 1910.104(b)(3)(viii).
Keep oxygen storage 50 feet from flammable gas storage locations under 5,000 cu ft (NTP) and 90 feet when the flammable gas capacity is 5,000 cu ft (NTP) or more. See Flammable gas distance in 1910.104(b)(3)(ix).
Bulk oxygen storage must be at least 25 feet from congested areas such as offices, lunchrooms, locker rooms, time clocks, and similar places where people gather. See Congested areas in 1910.104(b)(3)(xiii).
Yes. The distances in many of the distance paragraphs do not apply if protective firewalls of adequate height are located between the oxygen installation and the exposure; in those cases the installation may be as close as 1 foot from the firewall. See the exceptions in 1910.104(b)(3)(xviii).
Permanently installed containers must have substantial noncombustible supports on firm noncombustible foundations. See Foundations and supports in 1910.104(b)(4)(i).
Liquid oxygen containers must meet the impact test requirements of ASME Boiler and Pressure Vessel Code paragraph UG-84 as incorporated by reference. High-pressure gaseous oxygen containers must comply with either ASME Section VIII or DOT specifications and regulations. See Liquid construction in 1910.104(b)(4)(ii) and Gaseous construction options in 1910.104(b)(4)(iii).
Piping, tubing, and fittings must be suitable for oxygen service and the pressures/temperatures involved; piping and tubing should conform to ANSI B31.1 (Gas and Air Piping Systems) as referenced. Materials for very low temperature service must meet impact test requirements. See Selection in 1910.104(b)(5)(i), Specification in 1910.104(b)(5)(ii), and fabrication for low temps in 1910.104(b)(5)(iii).
Yes—every bulk oxygen storage container must have safety relief devices as required by the applicable ASME code or DOT specifications; ASME containers must meet Compressed Gas Association relief device provisions, insulation casings must have reliefs, and devices must be located or designed to prevent moisture freeze-up. See General relief device rule in 1910.104(b)(6)(i), ASME specifics in 1910.104(b)(6)(iii), insulation reliefs in 1910.104(b)(6)(iv), and moisture protection in 1910.104(b)(6).
Vaporizer heating must be indirect (steam, water, air, or nonreactive solutions), and if electric heaters are the primary heat source the vaporizer system must be electrically grounded. See Heating requirements in 1910.104(b)(7)(iii) and grounding in 1910.104(b)(7)(iv).
Before placing equipment in service, all components must be cleaned to remove oil, grease, or other readily oxidizable materials; joints may be welded or use suitable fittings and thread sealants must be oxygen-service compatible; after installation, all field-erected piping must be tested gas-tight at maximum operating pressure using oil-free, nonflammable test media. See Cleaning in 1910.104(b)(8)(i), joints in 1910.104(b)(8)(ii), and testing in 1910.104(b)(8)(v).
Containers, piping, valves, regulators, and accessories must be protected against physical damage and tampering; any enclosure with oxygen control equipment must be adequately vented; and the storage area must be permanently placarded with “OXYGEN - NO SMOKING - NO OPEN FLAMES” or an equivalent warning. See Security in 1910.104(b)(8)(vi), venting in 1910.104(b)(8)(vii), and placarding in 1910.104(b)(8)(viii).
No—bulk oxygen installations are not considered hazardous locations for electrical purposes under Subpart S; therefore, general-purpose or weatherproof wiring and equipment are acceptable depending on indoor/outdoor installation, but must still meet Subpart S provisions. See Electrical wiring guidance in 1910.104(b)(8)(ix).
Where user operation of equipment is required, legible operating instructions must be maintained at operating locations. See Operating instructions in 1910.104(b)(9).
Each charged bulk oxygen system must be maintained in a safe operating condition per the standard, and wood or long dry grass must be cut back within 15 feet of any bulk oxygen storage container. See Maintenance requirements in 1910.104(b)(10).