4.1 These test methods are useful in indicating the differences in flexure (breaking load, modulus of rupture, modulus of elasticity) between various slates. These test methods also provide one element in the comparison of slates.
1.1 These test methods cover determination of the breaking load, modulus of rupture and modulus of elasticity of slate by means of flexure tests.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.