No person operating, maintaining or conducting any hotel, club, restaurant, coffee house, lunchroom or other eating place wherein food is served to the public, shall use any ingredient or substance containing any sodium cyanide, potassium cyanide, oxalic acid, mercuric compound or other poisonous substances, for the cleaning of nickel, copper, silverware or silver-plated ware, and other articles or utensils used for the service or preparation of food or foodstuffs.
(Prior Code, § 115.047) Penalty, see § 115.999