California Code, Business and Professions Code - BPC § 13442

(a) It is unlawful for any person to sell, offer for sale, or cause or permit to be sold or offered for sale, or deliver or offer for delivery, any product used as a motor vehicle fuel for internal combustion engines at any place where motor vehicle fuels are kept or stored for sale, which does not conform to the requirements of this article, unless and until there shall be firmly attached to or painted upon each container, receptacle, pump, and inlet end of the fill pipe of each underground storage tank, or other equipment used for storage of motor vehicle fuel, from which or into which the motor vehicle fuel is drawn or poured for sale or delivery, a sign or label, plainly visible, comprising the brand, trademark, or trade name of such fuel, or the words “no brand,” that words shall be in letters of gothic type with a stroke of not less than one-eighth inch in width and not less than one inch in height, and also the words “not gasoline” in red letters of gothic type with a stroke of not less than one-half inch in width and not less than three inches in height, on a white background and not less than twice the size of any other letters or words appearing on or near the label or sign.

(b) The provisions of this article, as to the words “not gasoline,” shall not apply to signs or labels used in connection with the sale or delivery of kerosene, jet or turbine fuel, diesel fuel, liquefied petroleum gas, natural gas, or motor fuel comprised of a mixture of gasoline and lubricating oil properly labeled in accordance with the provisions of Article 9 (commencing with Section 13480).

(c) This section does not apply to electricity sold as a motor vehicle fuel.