California has been at the forefront of the movement to phase down HFCs, having been the first in the nation to adopt regulations to reduce the use of HFC refrigerants in commercial refrigeration equipment, as well as commercial and residential air conditioning equipment. Other states have followed suit and are currently deciding whether to follow the California model, wait for the final regulations from the federal AIM Act (due next year), or craft their own phasedown schedule.
Washington state is currently in the rulemaking process, having passed legislation in 2021 that authorized its Department of Ecology to establish maximum GWP thresholds for HFC refrigerants used in new stationary refrigeration and air conditioning equipment. As it stands now, the draft rule language would prohibit the use of refrigerants above 150 GWP in new stationary refrigeration equipment containing more than 50 pounds of refrigerant starting January 1, 2025. Also as of that date, refrigerants above 750 GWP would be prohibited from use in new stationary air conditioning equipment (VRF systems would have until January 1, 2026 to comply).