When more than 300 but less than 3,000 cubic feet, the storage locations are outdoors in an enclosure or within an enclosed interior space of non- or limited-combustible construction, with doors (or gates outdoors) that can be secured. Oxidizing gases are not stored with flammables and are separated from combustibles by 20 feet (5 feet if sprinklered) or enclosed in a cabinet of noncombustible construction with a minimum 1/2-hour fire protection rating.
When less than 301 cubic feet in a single smoke compartment, and handle with precautions as specified in NFPA 99-2012: 11.6.2.