Cal. HSC § 113916

“Smooth” means any of the following: (a) A food-contact surface that is free of pits, pinholes, cracks, crevices, inclusions, rough edges, and other surface imperfections detectable by visual or tactile inspection. (b) A nonfood-contact equipment surface equal to that of commercial grade hot-rolled steel free of visible scale. (c) A floor, wall, or ceiling having an even or level surface with no roughness or projections that render it difficult to clean.