The U.S. Supreme Court recently denied review of a D.C. Circuit Court of Appeals decision that invalidated an EPA final rule exempting major sources of hazardous air pollutants from normal emission standards during periods of startups, shutdowns and malfunctions (SSM). Am. Chemistry Council v. Sierra Club, No. 09-495 (3/8/10). The appeals court held that the Clean Air Act did not grant EPA the authority to create the SSM exemption. Am. Chemistry Council v. Sierra Club, 468 F.3d 810 (D.C. Cir. 2006). Several industry groups, supported by a U.S. Chamber of Commerce amicus brief, sought to appeal the decision. See Greenwire, March 8, 2010.