ASTM C689-03a

1.1 This test method covers the determination of the modulus of rupture of ceramic whiteware clays both dry and after conditioning at 50 or 80 % relative humidity, or both.

1.2 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 and health practices and determine the applicability of regulatory limitations prior to use.

This test method details the standard procedure for the determination of modulus of rupture of ceramic whiteware clays, both dry and after conditioning at specified relative humidity, or both. The apparatuses needed for this method are a conditioning cabinet, and a testing machine. Extruded, clay-flint, and solid cast specimens shall be prepared accordingly. Specific procedures as to handling, warpage, drying, and storage, and the corresponding calculations are discussed thoroughly.