This joint resolution revokes the waiver granted to the California Air Resources Board regarding new emissions standards for new 2024 and subsequent model year on-road heavy-duty vehicles and engines, off-road diesel engines, and off-road diesel-fueled auxiliary power units. (Under the Clean Air Act, California may seek waivers of the preemption prohibiting states from enacting certain emission standards.) Specifically, the joint resolution nullifies the Environmental Protection Agency notice titled California State Motor Vehicle and Engine and Nonroad Engine Pollution Control Standards; The ‘Omnibus’ Low NOX Regulation; Waiver of Preemption; Notice of Decision .
CRS summary — Public Law (2025-06-12)
| Date | Chamber | Question | Yea–Nay | Result | |
|---|---|---|---|---|---|
| 2025-04-30 | House | On Passage | 225–196 | Passed | ⭐ Became law |
| 2025-05-22 | Senate | On the Motion to Proceed | 51–46 | Motion to Proceed Agreed to | |
| 2025-05-22 | Senate | On the Joint Resolution | 49–46 | Joint Resolution Passed | ⭐ Became law |
Senate counts are senators only; a Vice President tie-breaking vote is not included (e.g. 50–50, passed).
