No person preparing or serving food shall prepare, sell, serve, or prepare for sale, either to be consumed on the premises or elsewhere, Kosher and non-Kosher food in the same place of business, unless such person:

(1) Keeps separate kitchens where the food is prepared, unless the food is prepared and served under rabbinical supervision;

(2) Keeps and uses separate and distinctly labeled or marked dishes and utensils in which the food is prepared and served; and

(3) Indicates on all signs and similar display advertising in, on, or about such person's premises, in block letters at least four inches in height, "Kosher and non-Kosher food prepared or served here."