【国外标准】 Standard Test Method for Acid Resistance of Porcelain Enamels(Citric Acid Spot Test)

3.1 This test method is intended specifically for testing the porcelain enamel finish on stoves, table tops, sinks, and other sanitary ware, laundry appliances, architectural units, etc., where the surface may come in contact with food acids at room temperature.3.2 Citric acid has been chosen as the test medium because it is one of the most common of the food acids and will generally provide a measurable result in its action on porcelain enamel.1.1 This test method covers a procedure for evaluating porcelain enamels in their resistance to citric acid exposure at room temperature. No attempt is made to categorize porcelain enamels as to their acid-resistance or non acid-resistance properties, since the requirements in the several branches of the industry differ.1.2 The test method is applicable for ware of various shapes providing they contain a substantially flat area approximately 50 mm in diameter.1.3 The test method is not applicable to finishes on chemical and hospital ware, which may come in contact with strong mineral acids, nor to cooking utensils, which may come in prolonged contact with hot acid solutions.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.