RIVERSIDE – The California Air Resources Board (CARB) reached a settlement agreement with Yanmar Power Technology Co., Ltd. of Osaka, Japan, for $16,196,120 for violating regulations aimed at reducing nitrogen oxides from off-road compression-ignition engines.

CARB identified three emissions violations: incomplete reporting of an auxiliary emission control device; use of incorrect test procedures not applicable to the engine type; and production of large spark-ignition engines not included in CARB’s certification authorizing sale of the engines in the state. The violations involved nearly 20,000 engines manufactured by Yanmar for use primarily in transportation refrigeration units. To address the violation involving the incomplete reporting of an auxiliary emission control device, the company made modifications that allowed it to comply with CARB’s certification requirements moving forward.

“Nitrogen oxide emissions worsen the health of Californians and increase the risk of respiratory illnesses, making it essential that manufacturers follow air quality laws both accurately and thoroughly,” said CARB Executive Officer Dr. Steven Cliff. “Californians breathe some of the worst air in the nation, and our enforcement efforts that keep companies accountable make it clear that everyone has to do their part to reduce the impacts of air pollution.”

Transport refrigeration units (TRUs) provide either cooling or heating for perishable products that are transported in various containers, including truck vans, semi-truck trailers, shipping containers, and railcars. Yanmar produces diesel engines used to power TRUs. Although TRU engines are relatively small, ranging from 9 to 36 horsepower, significant numbers of these engines congregate at distribution centers, truck stops, and other facilities, resulting in potential health risks to those who live and work nearby.  

The primary regulation implicated in this case was the Off-Road Compression-Ignition Engines and Equipment Regulation (https://ww2.arb.ca.gov/our-work/programs/road-compression-ignition-certification-program).