1.1 This test method determines the lethality (LD50 value, slope and 95 % confidence interval (CI)) and signs of acute toxicity from a material using a limited number of rats. The technique used in this test method is referred to as the “Stagewise, Adaptive Dose Method.”2 This test method is an alternative to the classical LD50 test and is applicable to both liquids and solids. 1.2 This test method is not recommended for test materials which typically produce deaths beyond two days postdosing. 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 and health practices and determine the applicability of regulatory limitations prior to use.