ASTM C650-04(2019)

3.1 This test method is intended for testing ceramic tile that are to be used for food counters, lavatories, and similar residential, medical, and commercial installations, where they may come in contact with food, chemical, and waste substances and for tile in areas where they may be exposed to contact with strong cleaning agents.

3.2 The specification of 10 % hydrochloric acid solution and 10 % potassium hydroxide solution as normal testing fluids, and the length of exposure time and temperature are based on experimental laboratory work and interlaboratory tests, where it was indicated that resistance to these two substances probably assures resistance also to any other acidic or alkaline substance coming in contact with tile, except hydrofluoric acid.

3.3 The validity of using color difference as means of determining the degree to which tile surfaces are affected by acids and alkalies has been established by interlaboratory test and was found to be more reliable than the determination of loss of gloss, particularly for unglazed tile and mat or semimat glazed surfaces. Lack of coordination between instrumental value and visual effect was noted only in the case of minute surface changes, detectable only by oblique viewing.

1.1 This test method covers a procedure for determining whether, and to what degree, ceramic tiles are affected by prolonged exposure to chemical substances that are commonly used in the household or for cleaning purposes as well as other more severe conditions.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 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.

1.4 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.