C.R.S. § 25-7-1504: Emission standards for new products.

(1) On and after January 1, 2026, except as described in section 25-7-1506, section 25-7-1503 (2), and subsection (3) of this section, a person shall not manufacture, distribute, sell, offer for sale, lease, or offer for lease in Colorado any of the following new products unless the emissions of the product do not exceed the following emissions limits, as applicable:

(a) Ten nanograms of NOx per joule for water heaters with a rated heat input capacity of up to seventy-five thousand BTUs per hour and for any unit with power assist;

(b) Fourteen nanograms of NOx per joule for water heaters with a rated heat input capacity of more than seventy-five thousand and less than two million BTUs per hour; or

(c) Fourteen nanograms of NOx per joule for fan-type central furnaces.

(2) Equipment that is certified to the most recently published version of the Energy Star program for the relevant equipment type is deemed to comply with the requirements of subsections (1) and (3) of this section.

(3) On and after January 1, 2031, a person shall not manufacture, distribute, sell, offer for sale, lease, or offer for lease in Colorado any new water heater or fan-type central furnace designed and listed exclusively for installation in a manufactured home unless the emissions of the product do not exceed forty nanograms of NOx per joule of heat input.