Consistent with the requirements under the Energy Policy and Conservation Act (EPCA), as amended, the Department of Energy (DOE) is examining whether to amend the current energy conservation standards for certain categories of Commercial Air Conditioning and Heating Equipment found at 10 CFR 431.97. As a result of this effort, DOE may either propose and adopt: (1) the amended ASHRAE standard 90.1-2019 levels; or (2) more-stringent standards if supported by "clear and convincing" evidence. DOE has proposed amended energy conservation standards that rely on new efficiency metrics and align with the amended efficiency levels in the industry standard, ASHRAE 90.1-2019. DOE has preliminarily determined that it lacks clear and convincing evidence required by the EPCA to adopt standards more stringent than the levels specified in the industry standard. DOE has also proposed definitions for space-constrained commercial package air conditioning and heating equipment and for small-duct, high-velocity commercial package air conditioning and heating equipment.