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CARB TRU compliance in 2026: what reefer fleets need to know
Lisa Nguyen2026-01-308 min read
California Transport Refrigeration Unit rules, deadlines, and how to stay compliant without losing trucks.
The California Air Resources Board Transport Refrigeration Unit (TRU) Airborne Toxic Control Measure continues to tighten. As of 2026, in-use TRU operators are required to meet ULETRU or zero-emission standards on a rolling fleet age basis. Here is what you need to do this quarter: pull every TRU serial number and engine tier, log it in your IDLeR system, schedule any older Tier 2 or Tier 3 units for retrofit or replacement, document every compliance event, and keep your ARB ID labels visible and current. Inspection during port operations is now common. Fines per violation are real and they stack. The shop side is straightforward, the operational side is where fleets get caught. Build the documentation discipline now, not when an inspector shows up.