No DoD contract may include a specification or standard that requires the use of a class I ozone-depleting substance or that can be met only through the use of such a substance unless the inclusion of the specification or standard is specifically authorized at a level no lower than a general or flag officer or a member of the Senior Executive Service of the requiring activity in accordance with section 326, Public Law 102-484 (10 U.S.C. 3201 note prec.). This restriction is in addition to any imposed by the Clean Air Act and applies after June 1, 1993, to all DoD contracts, regardless of place of performance.