This classification covers water used in the milling of porcelain enamel frit. Three classes of water are covered: For porcelain enamel frits, Class A water should cause no difficulties in the production of a high quality finish. Class B water may be used by slight compensations in processing. Mill addition water falling into Class C should be treated before use in order to preclude faulty enamel production. For analysis, the following elements and properties shall be determined: sampling, bicarbonate, calcium & magnesium, chloride, hardness, iron, manganese, pH, sulfate, and total solids.
