Public CommentProposedPublic CommentProposed Regulation
CARB Posts Draft Tier 5 Off-Road Diesel Engine Emission Standards
Tier 5 Off-Road Diesel Engine Emission StandardsCalifornia Air Resources BoardCalifornia
Announced
Feb 5, 2026
Description
CARB posted draft potential Tier 5 Regulation Order, Tier 4 In-Use Compliance Test Procedures, and Tier 5 Test Procedures on February 5, 2026. A public workshop was held on February 27, 2026. The Tier 5 standards would establish new criteria pollutant and CO2 emission standards for off-road diesel engines.
Sources
Key Findings
CARB Posts Draft Tier 5 Off-Road Diesel Engine Emission Standards
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