The floors of every establishment shall be smooth and cleanable, shall be of good quality nonabsorbent material and shall be kept in good repair and in a clean, sanitary condition at all times. The walls and ceilings shall be smooth, sound and cleanable and shall be kept painted with oil paint or other approved finishing material and maintained in good repair and in a clean and sanitary condition. In the proximity of sinks, mixers, stoves, ranges or other equipment where water, grease or other matter is likely to be splashed, walls shall be constructed of tile or other approved material to a sufficient height thoroughly to protect said walls; provided, the backs of stoves may be flashed with metal. Drainboards shall be made or constructed of metal, tile or approved substitutes. The use of wooden drainboards or wooden drainboards covered with metal is prohibited. Food preparation and utensil washing areas shall be painted with light-colored oil paint or enamel. (Ord. 855 § 2; prior code § 15.31).