On-Road Heavy-Duty Current Standards, Test Procedures and Regulatory Documents Categories Topics On-Road Heavy-Duty Vehicles Type Information Contact Diesel Hotline Email 8666DIESEL@arb.ca.gov Phone (866) 634-3735 / 866 6-DIESEL Section 1956.8, Title 13, California Code of Regulations contains California's emission standards for on-road heavy-duty engines and vehicles, and the following test procedures, as incorporated by reference. Heavy-Duty Otto-Cycle Engines and Vehicles "California Exhaust Emission Standards and Test Procedures for 1987 through 2003 Model Heavy-Duty Otto-Cycle Engines and Vehicles", as amended on December 27, 2000 "California Exhaust Emission Standards and Test Procedures for 2004 and Subsequent Model Heavy-Duty Otto-Cycle Engines and Vehicles", as amended September 9, 2021Heavy-Duty Diesel Engines and Vehicles "California Exhaust Emission Standards and Test Procedures for 1985 through 2003 Model Heavy-Duty Diesel Engines and Vehicles", as amended on December 12, 2002"California Exhaust Emission Standards and Test Procedures for 2004 and Subsequent Model Heavy-Duty Diesel Engines and Vehicles", as amended September 9, 2021 Related Resources Mobile Source Strategy Database Reporting Requirements Guidance to Vehicle Owners on 2024 Periodic Testing Requirements for Vehicles Subject to Annual Testing: California Registered Motorhomes and Agricultural Vehicles
