This measure would overturn an EPA decision that let California use stricter rules to cut smog-forming pollution (NOx) from heavy-duty trucks and engines. The EPA’s notice had granted California a waiver so it could enforce its “Omnibus Low NOx” standards. By nullifying that notice, this measure would block that waiver and stop those tougher California truck emission rules from taking effect under that approval .

In everyday terms, it would prevent California from using that specific EPA permission to require cleaner new heavy-duty engines. That could affect how quickly cleaner trucks roll out in California and could change what truck makers and fleet owners must do to sell or operate vehicles there .

• Key points
  • Who is affected: California regulators, truck and engine manufacturers, trucking fleets, and people living in areas affected by truck pollution .
  • What changes: The EPA’s decision granting California a waiver for its “Omnibus Low NOx” truck standards would be overturned, stopping those standards under that waiver .
  • When: The EPA notice being targeted was published January 6, 2025; the change would take effect if this measure becomes law and nullifies that notice .