Failure is defined by the MIA as any condition that results in structural damage to the stone. Although the Marble Institute of America (MIA) recommends that commercial stone floors be a minimum of 3/4 inch thick (2 cm), many installations are ongoing using thinner modular stone tiles. These pavers are normally 3/8 inch thick (1 cm) and of a size ranging from 12 x 12 to 24 x 24 inches (30.5 x 30.5 to 61 x 61 cm). The selected installation method is usually TCA F111, F112, or F113. F111 is for substrates subject to deflection, while F112 and F113 are for use where no bending stresses occur.
Some project specifications require these thin stone pavers to conform to the ASTM C-99 Compressive Strength, ASTM C 170 Modulus of Rupture, and ASTM C 880 Flexural strength test results published for the particular stone variety being used. When the stone fails, due to reasons discussed below, the stone contractor is held responsible, because the stone did not perform in accordance with the minimum ASTM requirements published for that stone variety.