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(a) The location of liquefied hydrogen storage, as determined by the maximum total quantity of liquefied hydrogen, shall be in the order of preference as indicated by Roman numerals in the following Table H-3:
Table H-3 Maximum Total Quantity of Liquefied Hydrogen Storage Permitted Size of Hydrogen Storage (Capacity in Gallons) 39.63 In excess Nature of Location (150 liters) 51 to 300 301 to 600 of 600 to 50 Outdoors I I I I In a separate building II II II Not permitted In a special room III III Not permitted Not permitted Inside buildings not in a special room and exposed to other occupancies IV Not Not Not permitted permitted permitted
NOTE: This table does not apply to the storage in dewars of the type generally used in laboratories for experimental purposes.
(b) The minimum distance in feet from liquefied hydrogen systems of indicated storage capacity located outdoors, in a separate building, or in a special room to any specified exposure shall be in accordance with Table H-4.
Table H-4 Minimum Distance (feet) from Liquefied Hydrogen Systems to Exposures Liquefied Hydrogen Storage 39.63 3,501 15,001 Type of Exposure (150 liters) to to 3,500 15,000 30,000 1. Fire-resistive Building and 5 5 5 Fire Walls* 2. Noncombustible Building* 25 50 75 3. Other Buildings* 50 75 100 4. Wall Openings, Air Compressor 75 75 75 Intakes, Inlets for Air- Conditioning or Ventilating Equipment 5. Flammable Liquids (Above- 50 75 100 ground and Vent or Fill Openings if Below Ground) (See 5491(c) and (d)) 6. Between Stationary Liquefied 5 5 5 Hydrogen Containers 7. Flammable Gas Storage 50 75 100 8. Liquid Oxygen Storage and 100 100 100 other Oxidizers (See 5491(c) and (d)) 9. Combustible Solids 50 75 100 10. Open Flames, Smoking and 50 50 50 Welding 11. Concentrations of People** 75 75 75 12. Public Ways, Railroads, and 25 50 75 Property Lines
* Refer to NFPA No. 220, "Standard Types of Building Construction," for definitions of construction types.
** In congested areas such as offices, lunchrooms, locker rooms, time clock areas, and places of public assembly.
NOTE: 1: The distances in Nos. 2, 3, 5, 7, 8, 9 and 12, in Table 2, may be reduced where protective structures, such as fire walls equal to height of top of the container, to safeguard the liquefied hydrogen storage system, are located between the liquefied hydrogen storage installation and the exposure. (See definition of Outdoor Location, Section 5415.)
NOTE: 2: Where protective structures are provided, ventilation and confinement of product shall be considered. The 5-foot distance in Nos. 1 and 6 facilitates maintenance and enhances ventilation.
1. Amendment of Table H-4 filed 3-2-76; effective thirtieth day thereafter (Register 76, No. 10).