Clean Air Rule

In March 2018, Thurston County Superior Court ruled that parts of the Clean Air Rule are invalid. The Superior Court's ruling prevents us from implementing the Clean Air Rule regulations. This means that compliance with the rule currently is suspended.

On Jan. 16, 2020, the Washington State Supreme Court ruled that the portions of the rule that applied to stationary sources, such as a factory, were upheld, but that the portions that applied to indirect sources, such as natural gas distributors and fuel suppliers, were invalid. The Supreme Court remanded the case to Thurston County Superior Court to determine how to separate the rule. 


Ecology adopted the Clean Air Rule in 2016 to address the major sources of greenhouse gases in Washington. The rule would require businesses that are responsible for large amounts of greenhouse gas emissions to cap and reduce their carbon emissions.

Although the Clean Air Rule is currently suspended, facilities covered by the Clean Air Rule still are required to report their emissions for the Greenhouse Gas Reporting program. This reporting program is required by Washington law