High-piled combustible storage is defined as any indoor storage of combustible materials in closely packed piles, on pallets, in racks, or on shelves where the top of storage is greater than 12 feet in height. Certain high-hazard commodities, such as Group A plastics, flammable liquids, rubber tires, idle pallets, and similar commodities, when stored over six feet in height, also qualify as high-piled combustible storage.

The incorporation of high-piled combustible storage requires special fire protection and life safety requirements as well as the issuance of an operational permit by the fire district. Plans detailing the following information regarding all high-piled combustible storage areas shall be submitted to the fire district for review and approval before an operational permit can be issued:

• Floor plan of the building showing locations and dimensions of all high-piled storage areas
• Usable storage height of each storage area
• Number of tiers within each rack, if applicable
• Commodity clearance between top of storage and the sprinkler deflector for each storage arrangement
• Commodity clearance between top of storage and the ceiling or roof deck for each storage arrangement
• Aisle dimensions between each storage array
• Location and classification of commodities in accordance with the fire code
• Location of commodities that are banded or encapsulated
• Location of aerosols, flammable and combustible liquids, and hazardous materials (the storage and retail display of aerosol products, flammable and combustible liquids and hazardous materials shall also be in accordance with the fire code);
• Locations of required fire department access doors;
• Type of fire-suppression and fire-detection systems, including small hose station locations
• Location of valves controlling the water supply for ceiling and in-rack sprinklers
• Type, location, and specifications (including the temperature rating of fusible elements) of smoke removal systems
• Dimension and location of transverse and longitudinal flue spaces
• Any additional information regarding required design features, commodities, storage arrangement, and fire protection features within the high-piled storage areas