The storage and use of flammable gases and flammable cryogenic fluids shall be in accordance with this chapter, NFPA 2 and NFPA 55. Compressed gases shall also comply with Chapter 53 and cryogenic fluids shall also comply with Chapter 55. Flammable cryogenic fluids shall comply with Section 5806. Hydrogen motor fuel-dispensing stations and repair garages and their associated above-ground hydrogen storage systems shall also be designed, constructed and maintained in accordance with Chapter 23.
Exceptions:
- Gases used as refrigerants in refrigeration systems (see Section 605).
- Liquefied petroleum gases and natural gases regulated by Chapter 61.
- Fuel-gas systems and appliances regulated under the International South Carolina Fuel Gas Code other than gaseous hydrogen systems and appliances.
- Pyrophoric gases in accordance with Chapter 64.
Permits shall be required as set forth in Section 105.6.
Flammable gases shall not be stored or used in Group A, E, I or R occupancies or in offices in Group B occupancies.
Exceptions:
- Cylinders of nonliquefied compressed gases not exceeding a capacity of 250 cubic feet (7.08 m3) or liquefied gases not exceeding a capacity of 40 pounds (18 kg) each at normal temperature and pressure (NTP) used for maintenance purposes, patient care or operation of equipment.
- Food service operations in accordance with Section 6103.2.1.7.
- Hydrogen gas systems located in a hydrogen fuel gas room constructed in accordance with Section 421 of the International South Carolina Building Code.
Ignition sources in areas containing flammable gases in storage or in use shall be controlled in accordance with Section 5003.7.
Exception: Fuel gas systems connected to building service utilities in accordance with the International South Carolina Fuel Gas Code.
Containers of liquefied flammable gases and flammable gases in solution shall be positioned in the upright position or positioned so that the pressure relief valve is in direct contact with the vapor space of the container.
Exceptions:
- Containers of flammable gases in solution with a capacity of 1.3 gallons (5 L) or less.
- Containers of flammable liquefied gases, with a capacity not exceeding 1.3 gallons (5 L), designed to preclude the discharge of liquid from safety relief devices.
Storage tanks shall be located outside in accordance with the following:
- Tanks and associated equipment shall be located with respect to foundations and supports of other structures such that the loads carried by the latter cannot be transmitted to the tank.
- The distance from any part of the tank to the nearest wall of a basement, pit, cellar or lot line shall be not less than 3 feet (914 mm).
- A minimum distance of 1 foot (305 mm), shell to shell, shall be maintained between underground tanks.
The tank shall be buried such that the top of the vacuum jacket is covered with not less than 1 foot (305 mm) of earth and with concrete not less than 4 inches (102 mm) thick placed over the earthen cover. The concrete shall extend not less than 1 foot (305 mm) horizontally beyond the footprint of the tank in all directions. Underground tanks shall be set on firm foundations constructed in accordance with the International South Carolina Building Code and surrounded with not less than 6 inches (152 mm) of noncorrosive inert material, such as sand.
Exception: The vertical extension of the vacuum jacket as required for service connections.
Metal hydride storage systems shall be marked with all of the following:
- Manufacturer's name.
- Service life indicating the last date the system can be used.
- A unique code or serial number specific to the unit.
- System name or product code that identifies the system by the type of chemistry used in the system.
- Emergency contact name, telephone number or other contact information.
- Limitations on refilling of containers to include rated charging pressure and capacity.
Metal hydride storage system valves shall be marked with all of the following:
- Manufacturer's name.
- Service life indicating the last date the valve can be used.
- Metal hydride service in which the valve can be used, or a product code that is traceable to this information.
Metal hydride storage system pressure relief devices shall be marked with all of the following:
- Manufacturer's name.
- Metal hydride service in which the device can be used, or a product code that is traceable to this information.
- Activation parameters to include temperature, pressure or both.
Cylinders, containers and tanks used in metal hydride storage systems shall be marked with all of the following:
- Manufacturer's name.
- Design specification to which the vessel was manufactured.
- Authorized body approving the design and initial inspection and test of the vessel.
- Manufacturer's original test date.
- Unique serial number for the vessel.
- Service life identifying the last date the vessel can be used.
- System name or product code that identifies the system by the type of chemistry used in the system.
Activation of a gas detection system alarm shall result in both of the following:
- Initiation of distinct audible and visible alarm signals both inside and outside of the hydrogen fuel gas room.
- Automatic activation of the mechanical exhaust ventilation system.