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 138 - Hydrogen
Section 5492 - Specific Requirements
Current through Register 2024 Notice Reg. No. 38, September 20, 2024
(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) |
||||
| Nature of Location | 39.63 (150 liters) to 50 | 51 to 300 | 301 to 600 | In excess of 600 |
| 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 permitted | Not permitted | Not 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 | ||||
| Type of Exposure | 39.63 (150 liters) 3,500 | 3,501 to 15,000 | 15,001 to 30,000 | |
| 1. | Fire-resistive Building and Fire Walls* | 5 | 5 | 5 |
| 2. | Noncombustible Building* | 25 | 50 | 75 |
| 3. | Other Buildings* | 50 | 75 | 100 |
| 4. | Wall Openings, Air Compressor Intakes, Inlets for Air-Conditioning or Ventilating Equipment | 75 | 75 | 75 |
| 5. | Flammable Liquids (Above-ground and Vent or Fill Openings if Below Ground) (See 5491(c) and (d)) | 50 | 75 | 100 |
| 6. | Between Stationary Liquefied Hydrogen Containers | 5 | 5 | 5 |
| 7. | Flammable Gas Storage | 50 | 75 | 100 |
| 8. | Liquid Oxygen Storage and other Oxidizers (See 5491(c) and (d)) | 100 | 100 | 100 |
| 9. | Combustible Solids | 50 | 75 | 100 |
| 10. | Open Flames, Smoking and Welding | 50 | 50 | 50 |
| 11. | Concentrations of People** | 75 | 75 | 75 |
| 12. | Public Ways, Railroads, and Property Lines | 25 | 50 | 75 |
* 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).
