In the inspection certificate, experts, who are independent of the production in the manufacturing or processing plant, confirm with numerical results from tests of the delivery itself or of the test units stated in standards, of which the delivery is one part that the delivered product corresponds to the agreements for the order. There is a distinction between: Inspection certificate A According to official regulations, issued by an official or officially accepted expert. Inspection certificate B According to terms of delivery of the customer or, in case provided, according to official regulations, issued by an expert appointed by the plant (factory expert). The required tests have to be executed by a test authority, which is independent of the production of the manufacturing or processing plant and disposes of the required equipment. Inspection certificate C According to the terms of delivery of the customer, issued by an expert authorized by the customer.