State regulation
(2) For purposes of this section, the following definitions apply: (A) The term “State regulation” means a law, regulation, or other requirement of a State or its political subdivisions. With respect to showerheads, faucets, water closets, and urinals, such term shall also mean a law, regulation, or other requirement of a river basin commission that has jurisdiction within a State. (B) The term “river basin commission” means— (i) a commission established by interstate compact to apportion, store, regulate, or otherwise manage or coordinate the management of the waters of a river basin; and (ii) a commission established under section 1962b(a) of this title .