Food establishment, food processing plant, or salvage operation facilities and equipment in use or new facilities and equipment for which contractual obligations are incurred before September 13, 1997, and which do not meet fully all the design and fabrication requirements of the Nebraska Pure Food Act shall be acceptable if they are in good repair and capable of being maintained in a sanitary condition and the food-contact surfaces are of safe materials. A food establishment, food processing plant, or salvage operation which has a change of ownership or extensive remodeling after September 13, 1997, shall comply with all applicable facility and equipment requirements of the act.