California Air Resources Board

CARB approves amendments to the In-Use Off-Road Regulation to further reduce emissions

The California Air Resources Board (CARB) approved amendments to the In-Use Off-Road Diesel-Fueled Fleets Regulation (Off-Road Regulation) on November 17, 2022, aimed at further reducing emissions from the off-road sector. For additional information regarding the approved amendments please refer to the press release.

The California Air Resources Board staff have developed Proposed Amendments to the In-Use Off-Road Diesel-Fueled Fleets Regulation (Off-Road Regulation) that will reduce emissions of criteria pollutants and toxics from off-road diesel vehicles operating in California, beyond the reductions being achieved via the ongoing implementation of the existing Off-Road Regulation. These criteria pollutant emission reductions are driven by the Proposed 2022 State Strategy for the State Implementation Plan, which sets a goal of reducing NOx emissions by 4.0 tons per day in the offroad diesel sector through this action, as well as the need to reduce diesel particulate matter at a statewide level to reduce the health risk throughout California, especially in communities that experience disproportionate burdens from exposure to toxic air contaminants. 

The Proposed Amendments would reduce emissions by requiring that fleets phaseout operation of their oldest and highest emitting offroad diesel vehicles, prohibiting the addition of high emitting vehicles to a fleet, and requiring the use of R99 or R100 renewable diesel in offroad diesel vehicles. There are also proposed requirements applicable to prime contractors and public works awarding bodies to obtain and retain a fleet’s valid Certificate of Reported Compliance prior to awarding a contract or hiring a fleet. The Proposed Amendments also aim to encourage the adoption of zero-emission vehicles which is vital to California’s long-term air quality goals by providing voluntary compliance flexibility options for fleets that adopt zero-emission technology. 

All regulatory documents for the Proposed Amendments are available on CARB’s rulemaking activity page.