In American Textile Mfrs. Inst., Inc. v. Donovan, 452 U.S. 490, 101 S.Ct. 2478, 69 L.Ed.2d 185 (1981) ("Cotton Dust "), upholding the Secretary's understanding that the "feasibility" criterion of Sec. 6(b)(5) of the Occupational Safety and Health Act was not a cost-benefit standard, the Court observed that "when Congress has intended that an agency engage in cost-benefit analysis, it has clearly indicated such intent on the face of the statute." 452 U.S. at 510, 101 S.Ct. at 2491. But it cited approvingly Forester and Aqua Slide 'N' Dive (which find "unreasonable risk" to incorporate cost-benefit balancing), id. at 510-11 n. 30, 101 S.Ct. at 2491 n. 30, and went on explicitly to leave open the question of Sec. 3(8)'s meaning apart from toxics regulation: "This is not to say that Sec. 3(8) might not require the balancing of costs and benefits for standards promulgated under provisions other than Sec. 6(b)(5) of the Act." Id. at 513 n. 32, 101 S.Ct. at 2493 n. 32. In American Textile Mfrs. Inst. v. Donovan, 452 U.S. 490, 101 S.Ct. 2478, 69 L.Ed.2d 185 (1981) ("Cotton Dust ") the Court held that the "feasibility" standard of Sec. 6(b)(5) of the Occupational Safety and Health Act of 1970 does not require the Secretary to balance cost and benefit in defining a standard, and clearly manifested the Court's belief that the Act did not permit the Secretary to do so. 452 U.S. at 506-22, 101 S.Ct. at 2489-97. In Cotton Dust, the Court made clear that, in light of the feasibility language in Sec. 6(b)(5), "reasonably necessary" in Sec. 3(8) did not require cost-benefit analysis. 452 U.S. at 513, 101 S.Ct. at 2492.