This test method covers the determination of the nilductility transition (NDT) temperature of ferritic steels, 5⁄8 in. (15.9 mm) and thicker.  This test method may be used whenever the inquiry, contract, order, or specification states that the steels are subject to fracture toughness requirements as determined by the drop-weight test.  The values stated in inch-pound units are to be regarded as the standard. 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.