Approval Details

Valid E.O.


This Executive Order approved the specified parts on on February 4, 1997.
As of Monday, April 15th, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

1997 and older model year gasoline, diesel and propane powered vehicles

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-421
  • Executive Order 421 / D421
  • ARB # D-421
  • Executive Order No: D-421
  • C.A.R.B. No. D-421
  • Resolution D-421
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-421 PDF

D-421 Document:

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