Approval Details

Valid E.O.


This Executive Order approved the specified parts on on June 9, 2003.
As of Sunday, July 14th, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

2003 and older on-road heavy-duty diesel engines certified to particulate matter emission standards of 0.60 g/bhp-hr or less and not otherwise equipped with an aftertreatment emission control system such as a catalytic converter or a particulate matter filter.The AZ Purifier and AZ Purimuffler exempted under this Executive Order can be installed on engines operated using standard California diesel with a maximum sulfur content of 500 ppmw, ultra low sulfur diesel with a maximum sulfur content of 15 ppmw, or PuriNOx water emulsion fuel based on standard California diesel.

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-420-3
  • Executive Order 420-3 / D420-3
  • ARB # D-420-3
  • Executive Order No: D-420-3
  • C.A.R.B. No. D-420-3
  • Resolution D-420-3
For Free CARB Executive Order Status verification, email an image of the device Executive Order label as well as the Year/Make/Model and Test Group # of the vehicle to [email protected]

Download: Executive Order D-420-3 PDF

D-420-3 Document:

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