California Code, Business and Professions Code - BPC § 5223

“Unzoned commercial or industrial area” means an area not zoned under authority of state law in which the land use is characteristic of that generally permitted only in areas which are actually zoned commercial or industrial under authority of state law, embracing all of the land on which one or more commercial or industrial activities are conducted, including all land within 1,000 feet, measured in each direction, from the nearest edge of the commercial or industrial building or activity on such land. As used in this section, “commercial or industrial activities” does not include the outdoor advertising business or the business of wayside fresh product vending.