1.1 These test methods are used to estimate the cracking resistance of vulcanized rubber exposed under dynamic strain conditions to a chamber atmosphere containing ozone at a fixed partial pressure. The effect of sun or ultraviolet light is excluded. 1.2 These test methods are not applicable to materials ordinarily classed as hard rubber, but are adaptable to molded or extruded soft rubber. 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.