The minimum standards established under section 21904(a) of this title, and any other guidelines and programs established under section 21903 of this title, shall be adoptable on a voluntary basis only.
(Pub. L. 106–468, title II, § 205, as added Pub. L. 115–401, § 2(5), Dec. 31, 2018, 132 Stat. 5341.)