(a) On or before October 1, 1990, the Commissioner of Consumer Protection, in consultation with the State Building Inspector and the Commissioners of Public Health and Energy and Environmental Protection, shall adopt regulations in accordance with the provisions of chapter 54 establishing minimum efficiency standards for plumbing fixtures and other water-using devices, as appropriate.

(b) The maximum water use allowed in the regulations adopted under subsection (a) of this section for showerheads, urinals, faucets and replacement aerators manufactured or sold on or after October 1, 1990, shall be as follows: For showerheads, 2.5 gallons per minute; for urinals, 1.0 gallons per flush; for bathroom sinks, lavatory and kitchen faucets and replacement aerators, 2.5 gallons per minute, except that lavatories in restrooms of public facilities shall be equipped with outlet devices which limit the flow rate to a maximum of 0.5 gallons per minute. The maximum water use allowed in the regulations adopted under subsection (a) of this section for tank-type toilets, flushometer-valve toilets, flushometer-tank toilets and electromechanical hydraulic toilets manufactured or sold on or after January 1, 1992, shall be 1.6 gallons per flush, unless and until equivalent standards for similar types of toilets are adopted by the American National Standards Institute, Inc.

(c) Notwithstanding the provisions of subsection (b) of this section, the Commissioner of Consumer Protection, after consultation with the State Building Inspector and the Commissioners of Public Health and Energy and Environmental Protection, may increase the level of efficiency for plumbing fixtures upon determination that such increase would promote the conservation of water and energy and be cost-effective for consumers who purchase and use such fixtures. Any increased efficiency standard shall be effective one year after its adoption.

(d) The Commissioner of Consumer Protection, in consultation with the Secretary of the Office of Policy and Management, the State Building Inspector and the Commissioners of Public Health and Energy and Environmental Protection, shall adopt regulations in accordance with the provisions of chapter 54 necessary to implement the provisions of sections 21a-86 to 21a-86g, inclusive. Such regulations shall provide for (1) the sale of plumbing fixtures which do not meet the standards if the commissioner determines that compliance is not feasible or an unnecessary hardship exists and (2) the sale of plumbing fixtures, including, but not limited to, antique reproduction plumbing fixtures, which do not meet the standards, provided such plumbing fixtures were in stock in a store located in the state before October 1, 1990, if a showerhead, urinal, faucet or replacement aerator or before January 1, 1992, if a tank-type toilet, flushometer-valve toilet, flushometer-tank toilet or electromechanical hydraulic toilet.