Commenting open: May 15, 2025 12:00AM PT - July 03, 2025 11:59PM PT.
Chapter 173-423 WAC, Clean Vehicles Program Rulemaking Formal Comment Period
Ecology is currently proposing amendments to Washington regulations that will track amendments to California’s Advanced Clean Trucks and Heavy-Duty Low-NOx Omnibus regulations currently adopted and/or under consideration by the California Air Resources Board (CARB). These amendments are important to streamline program implementation, provide additional compliance flexibility, and maintain consistency with other states and the federal government. The Advanced Clean Trucks regulations apply to medium- and heavy-duty engine and vehicle manufacturers and require zero-emission models to make up an increasing percentage of new vehicle sales in Washington, starting with engine model year 2025. The Heavy-Duty Low-NOx omnibus regulation applies to heavy-duty internal combustion engine manufacturers and requires them to meet more protective air quality standards, particularly on oxides of nitrogen and particulate matter, starting in model year 2026.
Comments are accepted from May 15, 2025 at 12:00 AM to July 3, 2025 at 11:59 PM. Visit the Chapter 173-423 WAC webpage here.
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Ecology is currently proposing amendments to Washington regulations that will track amendments to California’s Advanced Clean Trucks and Heavy-Duty Low-NOx Omnibus regulations currently adopted and/or under consideration by the California Air Resources Board (CARB). These amendments are important to streamline program implementation, provide additional compliance flexibility, and maintain consistency with other states and the federal government. The Advanced Clean Trucks regulations apply to medium- and heavy-duty engine and vehicle manufacturers and require zero-emission models to make up an increasing percentage of new vehicle sales in Washington, starting with engine model year 2025. The Heavy-Duty Low-NOx omnibus regulation applies to heavy-duty internal combustion engine manufacturers and requires them to meet more protective air quality standards, particularly on oxides of nitrogen and particulate matter, starting in model year 2026.
Comments are accepted from May 15, 2025 at 12:00 AM to July 3, 2025 at 11:59 PM. Visit the Chapter 173-423 WAC webpage here.
Contact Information
*Indicates Required Fields