California Air Resources Board

CARB conducts a variety of vehicle emissions testing to better understand vehicle emissions and their impact on air quality, climate change, and the public's health. In January 2016, CARB began a Truck and Bus Surveillance Program to evaluate the emissions from a wide range of in-use heavy-duty vehicles. Emissions testing is conducted using a heavy-duty chassis dynamometer and portable emissions measurement system (PEMS) to assess the real-world effectiveness of emission control systems, such as diesel particulate filters and selective catalytic reduction systems. With this type of information, more cost-effective regulations and strategies for reducing heavy-duty truck emissions can be developed.
More about this program