CARB’s Off-Road Diesel Regulation Phase-Out Alert

Back in 2022, the California Air Resources Board (CARB) introduced its latest amendments to the In-Use Off-Road Regulation, continuing its robust reduction of toxic air contaminants. The regulation requires all fleets to either retire older vehicles with newer vehicles, replace or repower older engines, or install diesel emissions controls under the hood. How this regulation applies to you depends on your fleet size and the engine model years of your equipment. Timely phase-outs are coming up shortly, so don’t fall asleep at the wheel!

Overview

Are you new to off-road diesel compliance rules? Here’s a brief refresher:

• All self-propelled off-road diesel equipment with at least 25 horsepower or more, as well as most two-engine diesel vehicles operating in California, must comply.
• Vehicles must be reported to the online DOORS reporting portal.
• Off-road diesel fleet owners must reduce nitrogen oxides (Nox) and particulate matter (PM) by making changes to older engines (retire, replace, or repower them) or installing exhaust retrofits using Verified Diesel Emission Control Strategies (VDECS).
• Fleet owners must limit idling to less than 5 minutes and create a written idling policy.
• Fleet owners must also disclose compliance when selling vehicles.

The requirements and phase-out dates are determined by your fleet size.

Add up the horsepower (hp) of all the off-road diesel equipment in your fleet: A Small Fleet has a total of less than 2,500 hp, a Medium Fleet has 2,501 to 5,000 hp, and Large Fleets have more than 5,000 combined hp. There is also a category for Ultra-Small Fleets with 500 hp or less.

Phase-outs are also determined by the model year (MY) of the engine. The oldest, dirtiest engines are in Tier 0 (MY 1994 or older). Tier 1 comprises MY 1999 or older, Tier 2 is MY 2003 or older, and Tiers 3 and 4i are MY 2006 or older. Check the emission control label on the engine or look for its U.S. EPA engine family name at the Off-Road Certification database to determine its Tier.

Phase-Outs Looming on the Horizon

For fleets with off-road diesel equipment that run at 25 hp or more—dozers, forklifts, excavators—new CARB rules are now in effect!⠀

As of January 1, 2024, Large Fleets with Tier 0 vehicles are prohibited from operating in California. Coming up on January 1, 2026, Large Fleets can no longer operate Tier 0 and Tier 1 equipment, and Tier 0 equipment will no longer be approved for operation of Medium Fleets.

Check out this optional compliance schedule for Ultra-Small Fleets, which extends the vehicle phase-out.

Since January 1, 2024, all fleets, regardless of size and model year, must use R99 or R100 renewable diesel fuel (go to the CARB site to view exemptions). Records of dates and volume of fuel purchased must be kept for three consecutive calendar years from the date of transaction.

Also since January of 2024, the CARB Off-Road Diesel Regulation restricts fleets from adding older tier vehicles to their fleets, specifically Tier 0 vehicles. Large and Medium Off-Road Diesel fleets are no longer permitted to add engines with Tier 0, 1, or 2 classifications to their fleets.

Contractors can now only hire fleets with a valid Certificate of Reported Compliance.

How to Be Compliant

Navigating through the nuances of the Off-Road Diesel Regulation is complex, and it can be extremely costly to update your vehicles to be compliant. The Good News: You may not need to retire vehicles or replace entire engines! Exhaust replacement parts and retrofit parts can be a financially sound workaround while also providing an exemption from future engine turnover requirements.

Interested in keeping your older off-road equipment? Contact us to perform a complete assessment. Our CARB consultants know every twist and turn of the Off-Road Diesel Regulation, can ensure that your entire fleet meets compliance, and even help guide you through the certification process. It just takes one phone call to (559) 579-1450 Ext. 303 to get on board and avoid fallouts from the upcoming phase-outs.