California Code of Regulations
Title 13 - Motor Vehicles
Division 3 - Air Resources Board
Chapter 1 - Motor Vehicle Pollution Control Devices
Article 4.5
Appendix A
Universal Citation: A CA Code of Regs A
Current through Register 2024 Notice Reg. No. 38, September 20, 2024
Table A-1 PM Emissions Factors by Engine Model Year (g/mile)
| Engine Certification Standard Model Year | Medium Heavy-Duty Diesel Vehicle (MHD) | Heavy Heavy-Duty Diesel Vehicle (HHD) |
| Pre-1991 | 1.65 | 3.36 |
| 1991-1993 | 0.84 | 1.25 |
| 1994-2006 | 0.43 | 0.81 |
| 2007-2009* | 0.06 | 0.11 |
| 2010 and newer* | 0.06 | 0.11 |
* If the engine is not equipped by the manufacturer with a diesel particulate filter, use the emission factor for the 1994-2006 model years
Table A-2 NOx Emissions Factors by Engine Model Year (g/mile)
| Engine Certification Standard Model Year | Medium Heavy-Duty Diesel Vehicle (MHD) | Heavy Heavy-Duty Diesel Vehicle (HHD) |
| 2003 and older | 14.2 | 22.0 |
| 2004-2006 | 6.7 | 12.0 |
| 2007-2009 | 4.0 | 7.0 |
| 2010 and newer | 0.8 | 1.6 |
Disclaimer: These regulations may not be the most recent version. California may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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