Washington Ecology issued the final amendments to their HFC rules on 10/29/2025. The amendments to Chapter 173-443 WAC, the “Hydrofluorocarbons (HFCs) and Other Fluorinated Greenhouse Gases” rule, take effect on November 29, 2025. The amendments “improve clarity, facilitate more consistent implementation, and reduce unintended impacts on businesses.” Ecology’s Concise Explanatory Statement, which is 19 pages long, is available here.