Gaseous hydrogen systems (b) apply on consumer premises supplied from outside by mobile equipment, except systems with less than 400 cubic feet total content and supplier plants. Liquefied hydrogen systems (c) apply on consumer premises except portable containers under 150 liters (39.63 gallons) and supplier plants. Gaseous systems: containers to ASME Section VIII (1968) or DOT specifications on noncombustible supports; containers marked "Hydrogen"; relief devices discharging upward to open air without impingement and protected from freezing moisture; piping suitable for hydrogen, no cast iron, to ANSI B31.1; installation supervised by knowledgeable personnel; equipment protected from damage and tampering; mobile units secured and bonded before discharge; storage placarded "HYDROGEN, FLAMMABLE GAS, NO SMOKING, NO OPEN FLAMES"; piping proved gas tight at maximum operating pressure. Systems are above ground, not under power lines, located by size per Table H-1 (outdoors preferred; over 15,000 cubic feet not permitted in special rooms) and separated from exposures per Table H-2; indoor systems under 3,000 cubic feet are at least 20 feet from flammables, 25 feet from ignition sources and people, 50 feet from air intakes and other flammable gas storage, with multiple systems at least 50 feet apart. Separate buildings and special rooms need noncombustible or 2-hour construction, ventilation of 1 square foot per 1,000 cubic feet, explosion venting of 1 square foot per 30 cubic feet, Class I Division 2 electrical and indirect heat. Operating instructions posted; combustibles kept 15 feet from containers. Liquefied systems: ASME or API 620 containers, steel supports over 18 inches with 2-hour fire protection, marking "LIQUEFIED HYDROGEN, FLAMMABLE GAS", relief devices per CGA S-1 and wherever liquid can be trapped, nonburning insulation, no uninsulated cold piping over asphalt, remote shutoff valves on containers over 2,000 gallons, gas-tight testing and retesting of containers out of service over 1 year, vaporizers with low temperature shutoff, Class I Group B Division 1 electrical within 3 feet and Division 2 within 25 feet of connection points, bonding and grounding. Location by Table H-3 and distances by Table H-4; sites fenced and placarded; relief venting 25 feet above grade for indoor locations; portable containers of 50 gallons or less indoors kept at stated distances (20, 25 and 50 feet) and upright, with no welding or smoking. A qualified person attends mobile unit unloading; units secured and grounded; weeds kept 25 feet away.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.