The walls and ceilings, shall be smooth, hard material and must be kept clean and sanitary and in good repair. All walls and ceilings of rooms in which food or drink is stored or prepared shall be finished in light color. The walls of all rooms in which food or drink is prepared or utensils are washed shall have a smooth, washable surface up to the level reached by splash or spray.
('68 Code, § 49.06)