Los Angeles County Municipal Code § 5003.8 Fire Code

Compressed gas cylinders shall be stored within gas cabinets, exhaust enclosures, or gas rooms. Portable or stationary tanks shall be stored within gas rooms or exhaust enclosures. Tank vehicles or railroad tank cars engaged in the use or dispensing of toxic or highly toxic gases shall be stored within a ventilated separate gas storage room or placed within an exhaust enclosure. When stationary or portable cylinders, containers, tanks, railroad tank cars, or tank vehicles are located outdoors for dispensing or use of toxic or highly toxic gases, gas cabinets or exhaust enclosures shall be provided.