; or (B) better enable improvements in the energy efficiency of the equipment and related energy using systems. (2) Antibacksliding exemption Section 325(o)(1) shall not apply to adjustments to covered product definitions made pursuant to this subsection (3) Procedure for modifying definition (A) In general Notice of any adjustment to the definition of a type of covered equipment and an explanation of the reasons therefor shall be published in the Federal Register and opportunity provided for public comment. (B) Consensus required Any amendment to the definition of a type of covered equipment under this subsection must have consensus support, as reflected in— (i) the outcome of negotiations conducted in accordance with the subchapter III of chapter 5 of title 5, United States Code (commonly known as the Negotiated Rulemaking Act of 1990 ); or (ii) the Secretary’s receipt of a statement that is submitted jointly by interested persons that are fairly representative of relevant points of view (including representatives of manufacturers of covered equipment, States, and efficiency advocates), as determined by the Secretary, which contains a recommended modified definition for a type of covered equipment. (4) Effect of a modified definition (A) For any type or class of equipment which becomes covered equipment pursuant to this subsection— (i) the Secretary may establish test procedures for such type or class of covered equipment pursuant to section 343 and energy conservation standards pursuant to subsections (o) and (p) of section 325; (ii) the Secretary may prescribe labeling rules pursuant to section 344 if the Secretary determines that labeling in accordance with that section is technologically and economically feasible and likely to assist purchasers in making purchasing decisions; (iii) section 327 shall begin to apply to such type or class of covered equipment in accordance with section 325(ii)(1)