CARB stands for the California Air Resources Board, a state agency focused on cutting air pollution and protecting public health by setting and enforcing air-quality standards. Its reach is well known in trucking because several of its rules apply to commercial vehicles.
Trucks operating in California generally have to meet CARB emissions requirements, which can affect engine model years, equipment, and registration. Dispatchers routing trucks into the state pay attention to CARB compliance so a non-compliant truck doesn’t get turned away or fined.