A method is provided for manufacturing a chemical mixture, such as a gasoline blend, which conforms to a set of regulations set by an outside public agency. The invention is directed to a set of regulations which require the manufacturer to prepare a master specification which sets control limits on the chemical characteristics of the chemical mixture and require that the master specification conform to a set of controlling criteria which are dependent upon such control limits--such as predicted exhaust pollution emissions from the burning of the subject gasoline blend. The method comprises the steps of: (a) blending quantities of chemical components to create a chemical mixture conforming to the controlling criteria, (b) analyzing the chemical mixture to determine the chemical characteristics of the chemical mixture, (c) preparing a test specification which conforms to the chemical characteristics of the chemical mixture, (d) determining whether the test specification conforms to the controlling criteria, and (e) accepting the test specification as the master specification if the determination in step (d) is positive.